Add fields order (#550)

PR approved by mistake.

.github/dependabot.yml

@@ -0,0 +1,10 @@
+version: 2
+updates:
+  - package-ecosystem: github-actions
+    directory: /
+    schedule:
+      interval: weekly
+  - package-ecosystem: gomod
+    directory: /
+    schedule:
+      interval: weekly

.github/workflows/test.yml

@@ -0,0 +1,36 @@
+on: [push, pull_request]
+name: Test
+jobs:
+  test:
+    strategy:
+      matrix:
+        go-version: [1.18.x, 1.21.x]
+        os: [ubuntu-latest, macos-latest]
+    runs-on: ${{ matrix.os }}
+    steps:
+    - name: Install Go
+      uses: actions/setup-go@v5
+      with:
+        go-version: ${{ matrix.go-version }}
+    - name: Checkout code
+      uses: actions/checkout@v4
+    - uses: actions/cache@v4
+      with:
+        path: ~/go/pkg/mod
+        key: ${{ runner.os }}-go-${{ hashFiles('**/go.sum') }}
+        restore-keys: |
+          ${{ runner.os }}-go-
+    - name: Test
+      run: go test -race -bench . -benchmem ./...
+    - name: Test CBOR
+      run: go test -tags binary_log ./...
+  coverage:
+    runs-on: ubuntu-latest
+    steps:
+    - name: Update coverage report
+      uses: ncruces/go-coverage-report@main
+      with:
+        report: 'true'
+        chart: 'true'
+        amend: 'true'
+      continue-on-error: true

.travis.yml

@@ -1,13 +0,0 @@
-language: go
-go:
-- "1.7"
-- "1.8"
-- "1.9"
-- "1.10"
-- "master"
-matrix:
-  allow_failures:
-      - go: "master"
-script:
-  - go test -v -race -cpu=1,2,4 -bench . -benchmem ./...
-  - go test -v -tags binary_log -race -cpu=1,2,4 -bench . -benchmem ./...

README.md

@@ -1,6 +1,6 @@
 # Zero Allocation JSON Logger
 
-[![godoc](http://img.shields.io/badge/godoc-reference-blue.svg?style=flat)](https://godoc.org/github.com/rs/zerolog) [![license](http://img.shields.io/badge/license-MIT-red.svg?style=flat)](https://raw.githubusercontent.com/rs/zerolog/master/LICENSE) [![Build Status](https://travis-ci.org/rs/zerolog.svg?branch=master)](https://travis-ci.org/rs/zerolog) [![Coverage](http://gocover.io/_badge/github.com/rs/zerolog)](http://gocover.io/github.com/rs/zerolog)
+[![godoc](http://img.shields.io/badge/godoc-reference-blue.svg?style=flat)](https://godoc.org/github.com/rs/zerolog) [![license](http://img.shields.io/badge/license-MIT-red.svg?style=flat)](https://raw.githubusercontent.com/rs/zerolog/master/LICENSE) [![Build Status](https://github.com/rs/zerolog/actions/workflows/test.yml/badge.svg)](https://github.com/rs/zerolog/actions/workflows/test.yml) [![Go Coverage](https://github.com/rs/zerolog/wiki/coverage.svg)](https://raw.githack.com/wiki/rs/zerolog/coverage.html)
 
 The zerolog package provides a fast and simple logger dedicated to JSON output.
 
@@ -18,20 +18,21 @@ Find out [who uses zerolog](https://github.com/rs/zerolog/wiki/Who-uses-zerolog)
 
 ## Features
 
-* Blazing fast
-* Low to zero allocation
-* Level logging
-* Sampling
-* Hooks
-* Contextual fields
-* `context.Context` integration
-* `net/http` helpers
-* JSON and CBOR encoding formats
-* Pretty logging for development
+* [Blazing fast](#benchmarks)
+* [Low to zero allocation](#benchmarks)
+* [Leveled logging](#leveled-logging)
+* [Sampling](#log-sampling)
+* [Hooks](#hooks)
+* [Contextual fields](#contextual-logging)
+* [`context.Context` integration](#contextcontext-integration)
+* [Integration with `net/http`](#integration-with-nethttp)
+* [JSON and CBOR encoding formats](#binary-encoding)
+* [Pretty logging for development](#pretty-logging)
+* [Error Logging (with optional Stacktrace)](#error-logging)
 
 ## Installation
 
-```go
+```bash
 go get -u github.com/rs/zerolog/log
 ```
 
@@ -51,9 +52,7 @@ import (
 
 func main() {
     // UNIX Time is faster and smaller than most timestamps
-    // If you set zerolog.TimeFieldFormat to an empty string,
-    // logs will write with UNIX time
-    zerolog.TimeFieldFormat = ""
+    zerolog.TimeFieldFormat = zerolog.TimeFormatUnix
 
     log.Print("hello world")
 }
@@ -61,7 +60,7 @@ func main() {
 // Output: {"time":1516134303,"level":"debug","message":"hello world"}
 ```
 > Note: By default log writes to `os.Stderr`
-> Note: The default log level for `log.Print` is *debug*
+> Note: The default log level for `log.Print` is *trace*
 
 ### Contextual Logging
 
@@ -76,15 +75,20 @@ import (
 )
 
 func main() {
-    zerolog.TimeFieldFormat = ""
+    zerolog.TimeFieldFormat = zerolog.TimeFormatUnix
 
     log.Debug().
         Str("Scale", "833 cents").
         Float64("Interval", 833.09).
         Msg("Fibonacci is everywhere")
+    
+    log.Debug().
+        Str("Name", "Tom").
+        Send()
 }
 
-// Output: {"time":1524104936,"level":"debug","Scale":"833 cents","Interval":833.09,"message":"Fibonacci is everywhere"}
+// Output: {"level":"debug","Scale":"833 cents","Interval":833.09,"time":1562212768,"message":"Fibonacci is everywhere"}
+// Output: {"level":"debug","Name":"Tom","time":1562212768}
 ```
 
 > You'll note in the above example that when adding contextual fields, the fields are strongly typed. You can find the full list of supported fields [here](#standard-types)
@@ -102,7 +106,7 @@ import (
 )
 
 func main() {
-    zerolog.TimeFieldFormat = ""
+    zerolog.TimeFieldFormat = zerolog.TimeFormatUnix
 
     log.Info().Msg("hello world")
 }
@@ -120,6 +124,7 @@ func main() {
 * warn (`zerolog.WarnLevel`, 2)
 * info (`zerolog.InfoLevel`, 1)
 * debug (`zerolog.DebugLevel`, 0)
+* trace (`zerolog.TraceLevel`, -1)
 
 You can set the Global logging level to any of these options using the `SetGlobalLevel` function in the zerolog package, passing in one of the given constants above, e.g. `zerolog.InfoLevel` would be the "info" level.  Whichever level is chosen, all logs with a level greater than or equal to that level will be written. To turn off logging entirely, pass the `zerolog.Disabled` constant.
 
@@ -138,7 +143,7 @@ import (
 )
 
 func main() {
-    zerolog.TimeFieldFormat = ""
+    zerolog.TimeFieldFormat = zerolog.TimeFormatUnix
     debug := flag.Bool("debug", false, "sets log level to debug")
 
     flag.Parse()
@@ -189,7 +194,7 @@ import (
 )
 
 func main() {
-    zerolog.TimeFieldFormat = ""
+    zerolog.TimeFieldFormat = zerolog.TimeFormatUnix
 
     log.Log().
         Str("foo", "bar").
@@ -199,6 +204,80 @@ func main() {
 // Output: {"time":1494567715,"foo":"bar"}
 ```
 
+### Error Logging
+
+You can log errors using the `Err` method
+
+```go
+package main
+
+import (
+	"errors"
+
+	"github.com/rs/zerolog"
+	"github.com/rs/zerolog/log"
+)
+
+func main() {
+	zerolog.TimeFieldFormat = zerolog.TimeFormatUnix
+
+	err := errors.New("seems we have an error here")
+	log.Error().Err(err).Msg("")
+}
+
+// Output: {"level":"error","error":"seems we have an error here","time":1609085256}
+```
+
+> The default field name for errors is `error`, you can change this by setting `zerolog.ErrorFieldName` to meet your needs.
+
+#### Error Logging with Stacktrace
+
+Using `github.com/pkg/errors`, you can add a formatted stacktrace to your errors. 
+
+```go
+package main
+
+import (
+	"github.com/pkg/errors"
+	"github.com/rs/zerolog/pkgerrors"
+
+	"github.com/rs/zerolog"
+	"github.com/rs/zerolog/log"
+)
+
+func main() {
+	zerolog.TimeFieldFormat = zerolog.TimeFormatUnix
+	zerolog.ErrorStackMarshaler = pkgerrors.MarshalStack
+
+	err := outer()
+	log.Error().Stack().Err(err).Msg("")
+}
+
+func inner() error {
+	return errors.New("seems we have an error here")
+}
+
+func middle() error {
+	err := inner()
+	if err != nil {
+		return err
+	}
+	return nil
+}
+
+func outer() error {
+	err := middle()
+	if err != nil {
+		return err
+	}
+	return nil
+}
+
+// Output: {"level":"error","stack":[{"func":"inner","line":"20","source":"errors.go"},{"func":"middle","line":"24","source":"errors.go"},{"func":"outer","line":"32","source":"errors.go"},{"func":"main","line":"15","source":"errors.go"},{"func":"main","line":"204","source":"proc.go"},{"func":"goexit","line":"1374","source":"asm_amd64.s"}],"error":"seems we have an error here","time":1609086683}
+```
+
+> zerolog.ErrorStackMarshaler must be set in order for the stack to output anything.
+
 #### Logging Fatal Messages
 
 ```go
@@ -215,7 +294,7 @@ func main() {
     err := errors.New("A repo man spends his life getting into tense situations")
     service := "myservice"
 
-    zerolog.TimeFieldFormat = ""
+    zerolog.TimeFieldFormat = zerolog.TimeFormatUnix
 
     log.Fatal().
         Err(err).
@@ -229,6 +308,7 @@ func main() {
 
 > NOTE: Using `Msgf` generates one allocation even when the logger is disabled.
 
+
 ### Create logger instance to manage different outputs
 
 ```go
@@ -319,6 +399,8 @@ log.Logger = log.With().Str("foo", "bar").Logger()
 
 ### Add file and line number to log
 
+Equivalent of `Llongfile`:
+
 ```go
 log.Logger = log.With().Caller().Logger()
 log.Info().Msg("hello world")
@@ -326,16 +408,27 @@ log.Info().Msg("hello world")
 // Output: {"level": "info", "message": "hello world", "caller": "/go/src/your_project/some_file:21"}
 ```
 
+Equivalent of `Lshortfile`:
+
+```go
+zerolog.CallerMarshalFunc = func(pc uintptr, file string, line int) string {
+    return filepath.Base(file) + ":" + strconv.Itoa(line)
+}
+log.Logger = log.With().Caller().Logger()
+log.Info().Msg("hello world")
+
+// Output: {"level": "info", "message": "hello world", "caller": "some_file:21"}
+```
 
 ### Thread-safe, lock-free, non-blocking writer
 
-If your writer might be slow or not thread-safe and you need your log producers to never get slowed down by a slow writer, you can use a `diode.Writer` as follow:
+If your writer might be slow or not thread-safe and you need your log producers to never get slowed down by a slow writer, you can use a `diode.Writer` as follows:
 
 ```go
 wr := diode.NewWriter(os.Stdout, 1000, 10*time.Millisecond, func(missed int) {
 		fmt.Printf("Logger Dropped %d messages", missed)
 	})
-log := zerolog.New(w)
+log := zerolog.New(wr)
 log.Print("test")
 ```
 
@@ -410,6 +503,58 @@ stdlog.Print("hello world")
 // Output: {"foo":"bar","message":"hello world"}
 ```
 
+### context.Context integration
+
+Go contexts are commonly passed throughout Go code, and this can help you pass
+your Logger into places it might otherwise be hard to inject.  The `Logger`
+instance may be attached to Go context (`context.Context`) using
+`Logger.WithContext(ctx)` and extracted from it using `zerolog.Ctx(ctx)`.
+For example:
+
+```go
+func f() {
+    logger := zerolog.New(os.Stdout)
+    ctx := context.Background()
+
+    // Attach the Logger to the context.Context
+    ctx = logger.WithContext(ctx)
+    someFunc(ctx)
+}
+
+func someFunc(ctx context.Context) {
+    // Get Logger from the go Context. if it's nil, then
+    // `zerolog.DefaultContextLogger` is returned, if
+    // `DefaultContextLogger` is nil, then a disabled logger is returned.
+    logger := zerolog.Ctx(ctx)
+    logger.Info().Msg("Hello")
+}
+```
+
+A second form of `context.Context` integration allows you to pass the current
+context.Context into the logged event, and retrieve it from hooks.  This can be
+useful to log trace and span IDs or other information stored in the go context,
+and facilitates the unification of logging and tracing in some systems:
+
+```go
+type TracingHook struct{}
+
+func (h TracingHook) Run(e *zerolog.Event, level zerolog.Level, msg string) {
+    ctx := e.GetCtx()
+    spanId := getSpanIdFromContext(ctx) // as per your tracing framework
+    e.Str("span-id", spanId)
+}
+
+func f() {
+    // Setup the logger
+    logger := zerolog.New(os.Stdout)
+    logger = logger.Hook(TracingHook{})
+
+    ctx := context.Background()
+    // Use the Ctx function to make the context available to the hook
+    logger.Info().Ctx(ctx).Msg("Hello")
+}
+```
+
 ### Integration with `net/http`
 
 The `github.com/rs/zerolog/hlog` package provides some helpers to integrate zerolog with `http.Handler`.
@@ -429,11 +574,11 @@ c := alice.New()
 c = c.Append(hlog.NewHandler(log))
 
 // Install some provided extra handler to set some request's context fields.
-// Thanks to those handler, all our logs will come with some pre-populated fields.
+// Thanks to that handler, all our logs will come with some prepopulated fields.
 c = c.Append(hlog.AccessHandler(func(r *http.Request, status, size int, duration time.Duration) {
     hlog.FromRequest(r).Info().
         Str("method", r.Method).
-        Str("url", r.URL.String()).
+        Stringer("url", r.URL).
         Int("status", status).
         Int("size", size).
         Dur("duration", duration).
@@ -463,23 +608,44 @@ if err := http.ListenAndServe(":8080", nil); err != nil {
 }
 ```
 
+## Multiple Log Output
+`zerolog.MultiLevelWriter` may be used to send the log message to multiple outputs. 
+In this example, we send the log message to both `os.Stdout` and the in-built ConsoleWriter.
+```go
+func main() {
+	consoleWriter := zerolog.ConsoleWriter{Out: os.Stdout}
+
+	multi := zerolog.MultiLevelWriter(consoleWriter, os.Stdout)
+
+	logger := zerolog.New(multi).With().Timestamp().Logger()
+
+	logger.Info().Msg("Hello World!")
+}
+
+// Output (Line 1: Console; Line 2: Stdout)
+// 12:36PM INF Hello World!
+// {"level":"info","time":"2019-11-07T12:36:38+03:00","message":"Hello World!"}
+```
+
 ## Global Settings
 
-Some settings can be changed and will by applied to all loggers:
+Some settings can be changed and will be applied to all loggers:
 
 * `log.Logger`: You can set this value to customize the global logger (the one used by package level methods).
-* `zerolog.SetGlobalLevel`: Can raise the minimum level of all loggers. Set this to `zerolog.Disabled` to disable logging altogether (quiet mode).
+* `zerolog.SetGlobalLevel`: Can raise the minimum level of all loggers. Call this with `zerolog.Disabled` to disable logging altogether (quiet mode).
 * `zerolog.DisableSampling`: If argument is `true`, all sampled loggers will stop sampling and issue 100% of their log events.
 * `zerolog.TimestampFieldName`: Can be set to customize `Timestamp` field name.
 * `zerolog.LevelFieldName`: Can be set to customize level field name.
 * `zerolog.MessageFieldName`: Can be set to customize message field name.
 * `zerolog.ErrorFieldName`: Can be set to customize `Err` field name.
-* `zerolog.TimeFieldFormat`: Can be set to customize `Time` field value formatting. If set with an empty string, times are formated as UNIX timestamp.
-    // DurationFieldUnit defines the unit for time.Duration type fields added
-    // using the Dur method.
-* `DurationFieldUnit`: Sets the unit of the fields added by `Dur` (default: `time.Millisecond`).
-* `DurationFieldInteger`: If set to true, `Dur` fields are formatted as integers instead of floats.
-* `ErrorHandler`: Called whenever zerolog fails to write an event on its output. If not set, an error is printed on the stderr. This handler must be thread safe and non-blocking.
+* `zerolog.TimeFieldFormat`: Can be set to customize `Time` field value formatting. If set with `zerolog.TimeFormatUnix`, `zerolog.TimeFormatUnixMs` or `zerolog.TimeFormatUnixMicro`, times are formatted as UNIX timestamp.
+* `zerolog.DurationFieldUnit`: Can be set to customize the unit for time.Duration type fields added by `Dur` (default: `time.Millisecond`).
+* `zerolog.DurationFieldInteger`: If set to `true`, `Dur` fields are formatted as integers instead of floats (default: `false`). 
+* `zerolog.ErrorHandler`: Called whenever zerolog fails to write an event on its output. If not set, an error is printed on the stderr. This handler must be thread safe and non-blocking.
+* `zerolog.FloatingPointPrecision`: If set to a value other than -1, controls the number
+of digits when formatting float numbers in JSON. See
+[strconv.FormatFloat](https://pkg.go.dev/strconv#FormatFloat)
+for more details.
 
 ## Field Types
 
@@ -493,16 +659,21 @@ Some settings can be changed and will by applied to all loggers:
 
 ### Advanced Fields
 
-* `Err`: Takes an `error` and render it as a string using the `zerolog.ErrorFieldName` field name.
-* `Timestamp`: Insert a timestamp field with `zerolog.TimestampFieldName` field name and formatted using `zerolog.TimeFieldFormat`.
-* `Time`: Adds a field with the time formated with the `zerolog.TimeFieldFormat`.
-* `Dur`: Adds a field with a `time.Duration`.
+* `Err`: Takes an `error` and renders it as a string using the `zerolog.ErrorFieldName` field name.
+* `Func`: Run a `func` only if the level is enabled.
+* `Timestamp`: Inserts a timestamp field with `zerolog.TimestampFieldName` field name, formatted using `zerolog.TimeFieldFormat`.
+* `Time`: Adds a field with time formatted with `zerolog.TimeFieldFormat`.
+* `Dur`: Adds a field with `time.Duration`.
 * `Dict`: Adds a sub-key/value as a field of the event.
+* `RawJSON`: Adds a field with an already encoded JSON (`[]byte`)
+* `Hex`: Adds a field with value formatted as a hexadecimal string (`[]byte`)
 * `Interface`: Uses reflection to marshal the type.
 
+Most fields are also available in the slice format (`Strs` for `[]string`, `Errs` for `[]error` etc.)
+
 ## Binary Encoding
 
-In addition to the default JSON encoding, `zerolog` can produce binary logs using [CBOR](http://cbor.io) encoding. The choice of encoding can be decided at compile time using the build tag `binary_log` as follows:
+In addition to the default JSON encoding, `zerolog` can produce binary logs using [CBOR](https://cbor.io) encoding. The choice of encoding can be decided at compile time using the build tag `binary_log` as follows:
 
 ```bash
 go build -tags binary_log .
@@ -514,10 +685,12 @@ with zerolog library is [CSD](https://github.com/toravir/csd/).
 ## Related Projects
 
 * [grpc-zerolog](https://github.com/cheapRoc/grpc-zerolog): Implementation of `grpclog.LoggerV2` interface using `zerolog`
+* [overlog](https://github.com/Trendyol/overlog): Implementation of `Mapped Diagnostic Context` interface using `zerolog`
+* [zerologr](https://github.com/go-logr/zerologr): Implementation of `logr.LogSink` interface using `zerolog`
 
 ## Benchmarks
 
-See [logbench](http://hackemist.com/logbench/) for more comprehensive and up-to-date benchmarks.
+See [logbench](http://bench.zerolog.io/) for more comprehensive and up-to-date benchmarks.
 
 All operations are allocation free (those numbers *include* JSON encoding):
 
@@ -578,7 +751,9 @@ Log a static string, without any context or `printf`-style templating:
 
 ## Caveats
 
-Note that zerolog does de-duplication fields. Using the same key multiple times creates multiple keys in final JSON:
+### Field duplication
+
+Note that zerolog does no de-duplication of fields. Using the same key multiple times creates multiple keys in final JSON:
 
 ```go
 logger := zerolog.New(os.Stderr).With().Timestamp().Logger()
@@ -588,4 +763,20 @@ logger.Info().
 // Output: {"level":"info","time":1494567715,"time":1494567715,"message":"dup"}
 ```
 
-However, it’s not a big deal as JSON accepts dup keys; the last one prevails.
+In this case, many consumers will take the last value, but this is not guaranteed; check yours if in doubt.
+
+### Concurrency safety
+
+Be careful when calling UpdateContext. It is not concurrency safe. Use the With method to create a child logger:
+
+```go
+func handler(w http.ResponseWriter, r *http.Request) {
+    // Create a child logger for concurrency safety
+    logger := log.Logger.With().Logger()
+
+    // Add context fields, for example User-Agent from HTTP headers
+    logger.UpdateContext(func(c zerolog.Context) zerolog.Context {
+        ...
+    })
+}
+```

array.go

@@ -49,7 +49,7 @@ func (*Array) MarshalZerologArray(*Array) {
 func (a *Array) write(dst []byte) []byte {
 	dst = enc.AppendArrayStart(dst)
 	if len(a.buf) > 0 {
-		dst = append(append(dst, a.buf...))
+		dst = append(dst, a.buf...)
 	}
 	dst = enc.AppendArrayEnd(dst)
 	putArray(a)
@@ -57,7 +57,7 @@ func (a *Array) write(dst []byte) []byte {
 }
 
 // Object marshals an object that implement the LogObjectMarshaler
-// interface and append append it to the array.
+// interface and appends it to the array.
 func (a *Array) Object(obj LogObjectMarshaler) *Array {
 	e := Dict()
 	obj.MarshalZerologObject(e)
@@ -67,28 +67,33 @@ func (a *Array) Object(obj LogObjectMarshaler) *Array {
 	return a
 }
 
-// Str append append the val as a string to the array.
+// Str appends the val as a string to the array.
 func (a *Array) Str(val string) *Array {
 	a.buf = enc.AppendString(enc.AppendArrayDelim(a.buf), val)
 	return a
 }
 
-// Bytes append append the val as a string to the array.
+// Bytes appends the val as a string to the array.
 func (a *Array) Bytes(val []byte) *Array {
 	a.buf = enc.AppendBytes(enc.AppendArrayDelim(a.buf), val)
 	return a
 }
 
-// Hex append append the val as a hex string to the array.
+// Hex appends the val as a hex string to the array.
 func (a *Array) Hex(val []byte) *Array {
 	a.buf = enc.AppendHex(enc.AppendArrayDelim(a.buf), val)
 	return a
 }
 
+// RawJSON adds already encoded JSON to the array.
+func (a *Array) RawJSON(val []byte) *Array {
+	a.buf = appendJSON(enc.AppendArrayDelim(a.buf), val)
+	return a
+}
+
 // Err serializes and appends the err to the array.
 func (a *Array) Err(err error) *Array {
-	marshaled := ErrorMarshalFunc(err)
-	switch m := marshaled.(type) {
+	switch m := ErrorMarshalFunc(err).(type) {
 	case LogObjectMarshaler:
 		e := newEvent(nil, 0)
 		e.buf = e.buf[:0]
@@ -96,7 +101,11 @@ func (a *Array) Err(err error) *Array {
 		a.buf = append(enc.AppendArrayDelim(a.buf), e.buf...)
 		putEvent(e)
 	case error:
-		a.buf = enc.AppendString(enc.AppendArrayDelim(a.buf), m.Error())
+		if m == nil || isNilValue(m) {
+			a.buf = enc.AppendNil(enc.AppendArrayDelim(a.buf))
+		} else {
+			a.buf = enc.AppendString(enc.AppendArrayDelim(a.buf), m.Error())
+		}
 	case string:
 		a.buf = enc.AppendString(enc.AppendArrayDelim(a.buf), m)
 	default:
@@ -106,97 +115,97 @@ func (a *Array) Err(err error) *Array {
 	return a
 }
 
-// Bool append append the val as a bool to the array.
+// Bool appends the val as a bool to the array.
 func (a *Array) Bool(b bool) *Array {
 	a.buf = enc.AppendBool(enc.AppendArrayDelim(a.buf), b)
 	return a
 }
 
-// Int append append i as a int to the array.
+// Int appends i as a int to the array.
 func (a *Array) Int(i int) *Array {
 	a.buf = enc.AppendInt(enc.AppendArrayDelim(a.buf), i)
 	return a
 }
 
-// Int8 append append i as a int8 to the array.
+// Int8 appends i as a int8 to the array.
 func (a *Array) Int8(i int8) *Array {
 	a.buf = enc.AppendInt8(enc.AppendArrayDelim(a.buf), i)
 	return a
 }
 
-// Int16 append append i as a int16 to the array.
+// Int16 appends i as a int16 to the array.
 func (a *Array) Int16(i int16) *Array {
 	a.buf = enc.AppendInt16(enc.AppendArrayDelim(a.buf), i)
 	return a
 }
 
-// Int32 append append i as a int32 to the array.
+// Int32 appends i as a int32 to the array.
 func (a *Array) Int32(i int32) *Array {
 	a.buf = enc.AppendInt32(enc.AppendArrayDelim(a.buf), i)
 	return a
 }
 
-// Int64 append append i as a int64 to the array.
+// Int64 appends i as a int64 to the array.
 func (a *Array) Int64(i int64) *Array {
 	a.buf = enc.AppendInt64(enc.AppendArrayDelim(a.buf), i)
 	return a
 }
 
-// Uint append append i as a uint to the array.
+// Uint appends i as a uint to the array.
 func (a *Array) Uint(i uint) *Array {
 	a.buf = enc.AppendUint(enc.AppendArrayDelim(a.buf), i)
 	return a
 }
 
-// Uint8 append append i as a uint8 to the array.
+// Uint8 appends i as a uint8 to the array.
 func (a *Array) Uint8(i uint8) *Array {
 	a.buf = enc.AppendUint8(enc.AppendArrayDelim(a.buf), i)
 	return a
 }
 
-// Uint16 append append i as a uint16 to the array.
+// Uint16 appends i as a uint16 to the array.
 func (a *Array) Uint16(i uint16) *Array {
 	a.buf = enc.AppendUint16(enc.AppendArrayDelim(a.buf), i)
 	return a
 }
 
-// Uint32 append append i as a uint32 to the array.
+// Uint32 appends i as a uint32 to the array.
 func (a *Array) Uint32(i uint32) *Array {
 	a.buf = enc.AppendUint32(enc.AppendArrayDelim(a.buf), i)
 	return a
 }
 
-// Uint64 append append i as a uint64 to the array.
+// Uint64 appends i as a uint64 to the array.
 func (a *Array) Uint64(i uint64) *Array {
 	a.buf = enc.AppendUint64(enc.AppendArrayDelim(a.buf), i)
 	return a
 }
 
-// Float32 append append f as a float32 to the array.
+// Float32 appends f as a float32 to the array.
 func (a *Array) Float32(f float32) *Array {
-	a.buf = enc.AppendFloat32(enc.AppendArrayDelim(a.buf), f)
+	a.buf = enc.AppendFloat32(enc.AppendArrayDelim(a.buf), f, FloatingPointPrecision)
 	return a
 }
 
-// Float64 append append f as a float64 to the array.
+// Float64 appends f as a float64 to the array.
 func (a *Array) Float64(f float64) *Array {
-	a.buf = enc.AppendFloat64(enc.AppendArrayDelim(a.buf), f)
+	a.buf = enc.AppendFloat64(enc.AppendArrayDelim(a.buf), f, FloatingPointPrecision)
 	return a
 }
 
-// Time append append t formated as string using zerolog.TimeFieldFormat.
+// Time appends t formatted as string using zerolog.TimeFieldFormat.
 func (a *Array) Time(t time.Time) *Array {
 	a.buf = enc.AppendTime(enc.AppendArrayDelim(a.buf), t, TimeFieldFormat)
 	return a
 }
 
-// Dur append append d to the array.
+// Dur appends d to the array.
 func (a *Array) Dur(d time.Duration) *Array {
-	a.buf = enc.AppendDuration(enc.AppendArrayDelim(a.buf), d, DurationFieldUnit, DurationFieldInteger)
+	a.buf = enc.AppendDuration(enc.AppendArrayDelim(a.buf), d, DurationFieldUnit, DurationFieldInteger, FloatingPointPrecision)
 	return a
 }
 
-// Interface append append i marshaled using reflection.
+// Interface appends i marshaled using reflection.
 func (a *Array) Interface(i interface{}) *Array {
 	if obj, ok := i.(LogObjectMarshaler); ok {
 		return a.Object(obj)
@@ -222,3 +231,10 @@ func (a *Array) MACAddr(ha net.HardwareAddr) *Array {
 	a.buf = enc.AppendMACAddr(enc.AppendArrayDelim(a.buf), ha)
 	return a
 }
+
+// Dict adds the dict Event to the array
+func (a *Array) Dict(dict *Event) *Array {
+	dict.buf = enc.AppendEndMarker(dict.buf)
+	a.buf = append(enc.AppendArrayDelim(a.buf), dict.buf...)
+	return a
+}

array_test.go

@@ -24,10 +24,15 @@ func TestArray(t *testing.T) {
 		Str("a").
 		Bytes([]byte("b")).
 		Hex([]byte{0x1f}).
+		RawJSON([]byte(`{"some":"json"}`)).
 		Time(time.Time{}).
 		IPAddr(net.IP{192, 168, 0, 10}).
-		Dur(0)
-	want := `[true,1,2,3,4,5,6,7,8,9,10,11.98122,12.987654321,"a","b","1f","0001-01-01T00:00:00Z","192.168.0.10",0]`
+		Dur(0).
+		Dict(Dict().
+			Str("bar", "baz").
+			Int("n", 1),
+		)
+	want := `[true,1,2,3,4,5,6,7,8,9,10,11.98122,12.987654321,"a","b","1f",{"some":"json"},"0001-01-01T00:00:00Z","192.168.0.10",0,{"bar":"baz","n":1}]`
 	if got := decodeObjectToStr(a.write([]byte{})); got != want {
 		t.Errorf("Array.write()\ngot:  %s\nwant: %s", got, want)
 	}

benchmark_test.go

@@ -1,8 +1,10 @@
 package zerolog
 
 import (
+	"context"
 	"errors"
-	"io/ioutil"
+	"io"
+	"net"
 	"testing"
 	"time"
 )
@@ -13,7 +15,7 @@ var (
 )
 
 func BenchmarkLogEmpty(b *testing.B) {
-	logger := New(ioutil.Discard)
+	logger := New(io.Discard)
 	b.ResetTimer()
 	b.RunParallel(func(pb *testing.PB) {
 		for pb.Next() {
@@ -23,7 +25,7 @@ func BenchmarkLogEmpty(b *testing.B) {
 }
 
 func BenchmarkDisabled(b *testing.B) {
-	logger := New(ioutil.Discard).Level(Disabled)
+	logger := New(io.Discard).Level(Disabled)
 	b.ResetTimer()
 	b.RunParallel(func(pb *testing.PB) {
 		for pb.Next() {
@@ -33,7 +35,7 @@ func BenchmarkDisabled(b *testing.B) {
 }
 
 func BenchmarkInfo(b *testing.B) {
-	logger := New(ioutil.Discard)
+	logger := New(io.Discard)
 	b.ResetTimer()
 	b.RunParallel(func(pb *testing.PB) {
 		for pb.Next() {
@@ -43,7 +45,7 @@ func BenchmarkInfo(b *testing.B) {
 }
 
 func BenchmarkContextFields(b *testing.B) {
-	logger := New(ioutil.Discard).With().
+	logger := New(io.Discard).With().
 		Str("string", "four!").
 		Time("time", time.Time{}).
 		Int("int", 123).
@@ -58,7 +60,7 @@ func BenchmarkContextFields(b *testing.B) {
 }
 
 func BenchmarkContextAppend(b *testing.B) {
-	logger := New(ioutil.Discard).With().
+	logger := New(io.Discard).With().
 		Str("foo", "bar").
 		Logger()
 	b.ResetTimer()
@@ -70,7 +72,7 @@ func BenchmarkContextAppend(b *testing.B) {
 }
 
 func BenchmarkLogFields(b *testing.B) {
-	logger := New(ioutil.Discard)
+	logger := New(io.Discard)
 	b.ResetTimer()
 	b.RunParallel(func(pb *testing.PB) {
 		for pb.Next() {
@@ -100,7 +102,7 @@ func BenchmarkLogArrayObject(b *testing.B) {
 	obj1 := obj{"a", "b", 2}
 	obj2 := obj{"c", "d", 3}
 	obj3 := obj{"e", "f", 4}
-	logger := New(ioutil.Discard)
+	logger := New(io.Discard)
 	b.ResetTimer()
 	b.ReportAllocs()
 	for i := 0; i < b.N; i++ {
@@ -147,18 +149,19 @@ func BenchmarkLogFieldType(b *testing.B) {
 		{"a", "a", 0},
 	}
 	objects := []obj{
-		obj{"a", "a", 0},
-		obj{"a", "a", 0},
-		obj{"a", "a", 0},
-		obj{"a", "a", 0},
-		obj{"a", "a", 0},
-		obj{"a", "a", 0},
-		obj{"a", "a", 0},
-		obj{"a", "a", 0},
-		obj{"a", "a", 0},
-		obj{"a", "a", 0},
+		{"a", "a", 0},
+		{"a", "a", 0},
+		{"a", "a", 0},
+		{"a", "a", 0},
+		{"a", "a", 0},
+		{"a", "a", 0},
+		{"a", "a", 0},
+		{"a", "a", 0},
+		{"a", "a", 0},
+		{"a", "a", 0},
 	}
 	errs := []error{errors.New("a"), errors.New("b"), errors.New("c"), errors.New("d"), errors.New("e")}
+	ctx := context.Background()
 	types := map[string]func(e *Event) *Event{
 		"Bool": func(e *Event) *Event {
 			return e.Bool("k", bools[0])
@@ -190,6 +193,9 @@ func BenchmarkLogFieldType(b *testing.B) {
 		"Errs": func(e *Event) *Event {
 			return e.Errs("k", errs)
 		},
+		"Ctx": func(e *Event) *Event {
+			return e.Ctx(ctx)
+		},
 		"Time": func(e *Event) *Event {
 			return e.Time("k", times[0])
 		},
@@ -218,7 +224,7 @@ func BenchmarkLogFieldType(b *testing.B) {
 			return e.Object("k", objects[0])
 		},
 	}
-	logger := New(ioutil.Discard)
+	logger := New(io.Discard)
 	b.ResetTimer()
 	for name := range types {
 		f := types[name]
@@ -234,12 +240,13 @@ func BenchmarkLogFieldType(b *testing.B) {
 
 func BenchmarkContextFieldType(b *testing.B) {
 	oldFormat := TimeFieldFormat
-	TimeFieldFormat = ""
+	TimeFieldFormat = TimeFormatUnix
 	defer func() { TimeFieldFormat = oldFormat }()
 	bools := []bool{true, false, true, false, true, false, true, false, true, false}
 	ints := []int{0, 1, 2, 3, 4, 5, 6, 7, 8, 9}
 	floats := []float64{0, 1, 2, 3, 4, 5, 6, 7, 8, 9}
 	strings := []string{"a", "b", "c", "d", "e", "f", "g", "h", "i", "j"}
+	stringer := net.IP{127, 0, 0, 1}
 	durations := []time.Duration{0, 1, 2, 3, 4, 5, 6, 7, 8, 9}
 	times := []time.Time{
 		time.Unix(0, 0),
@@ -270,18 +277,19 @@ func BenchmarkContextFieldType(b *testing.B) {
 		{"a", "a", 0},
 	}
 	objects := []obj{
-		obj{"a", "a", 0},
-		obj{"a", "a", 0},
-		obj{"a", "a", 0},
-		obj{"a", "a", 0},
-		obj{"a", "a", 0},
-		obj{"a", "a", 0},
-		obj{"a", "a", 0},
-		obj{"a", "a", 0},
-		obj{"a", "a", 0},
-		obj{"a", "a", 0},
+		{"a", "a", 0},
+		{"a", "a", 0},
+		{"a", "a", 0},
+		{"a", "a", 0},
+		{"a", "a", 0},
+		{"a", "a", 0},
+		{"a", "a", 0},
+		{"a", "a", 0},
+		{"a", "a", 0},
+		{"a", "a", 0},
 	}
 	errs := []error{errors.New("a"), errors.New("b"), errors.New("c"), errors.New("d"), errors.New("e")}
+	ctx := context.Background()
 	types := map[string]func(c Context) Context{
 		"Bool": func(c Context) Context {
 			return c.Bool("k", bools[0])
@@ -307,12 +315,18 @@ func BenchmarkContextFieldType(b *testing.B) {
 		"Strs": func(c Context) Context {
 			return c.Strs("k", strings)
 		},
+		"Stringer": func(c Context) Context {
+			return c.Stringer("k", stringer)
+		},
 		"Err": func(c Context) Context {
 			return c.Err(errs[0])
 		},
 		"Errs": func(c Context) Context {
 			return c.Errs("k", errs)
 		},
+		"Ctx": func(c Context) Context {
+			return c.Ctx(ctx)
+		},
 		"Time": func(c Context) Context {
 			return c.Time("k", times[0])
 		},
@@ -344,7 +358,7 @@ func BenchmarkContextFieldType(b *testing.B) {
 			return c.Timestamp()
 		},
 	}
-	logger := New(ioutil.Discard)
+	logger := New(io.Discard)
 	b.ResetTimer()
 	for name := range types {
 		f := types[name]

binary_test.go

@@ -7,7 +7,6 @@ import (
 	"errors"
 	"fmt"
 
-	//	"io/ioutil"
 	stdlog "log"
 	"time"
 )
@@ -108,6 +107,19 @@ func ExampleLogger_Printf() {
 	// Output: {"level":"debug","message":"hello world"}
 }
 
+func ExampleLogger_Trace() {
+	dst := bytes.Buffer{}
+	log := New(&dst)
+
+	log.Trace().
+		Str("foo", "bar").
+		Int("n", 123).
+		Msg("hello world")
+
+	fmt.Println(decodeIfBinaryToString(dst.Bytes()))
+	// Output: {"level":"trace","foo":"bar","n":123,"message":"hello world"}
+}
+
 func ExampleLogger_Debug() {
 	dst := bytes.Buffer{}
 	log := New(&dst)
@@ -351,6 +363,42 @@ func ExampleEvent_Durs() {
 	// Output: {"foo":"bar","durs":[10000,20000],"message":"hello world"}
 }
 
+func ExampleEvent_Fields_map() {
+	fields := map[string]interface{}{
+		"bar": "baz",
+		"n":   1,
+	}
+
+	dst := bytes.Buffer{}
+	log := New(&dst)
+
+	log.Log().
+		Str("foo", "bar").
+		Fields(fields).
+		Msg("hello world")
+
+	fmt.Println(decodeIfBinaryToString(dst.Bytes()))
+	// Output: {"foo":"bar","bar":"baz","n":1,"message":"hello world"}
+}
+
+func ExampleEvent_Fields_slice() {
+	fields := []interface{}{
+		"bar", "baz",
+		"n", 1,
+	}
+
+	dst := bytes.Buffer{}
+	log := New(&dst)
+
+	log.Log().
+		Str("foo", "bar").
+		Fields(fields).
+		Msg("hello world")
+
+	fmt.Println(decodeIfBinaryToString(dst.Bytes()))
+	// Output: {"foo":"bar","bar":"baz","n":1,"message":"hello world"}
+}
+
 func ExampleContext_Dict() {
 	dst := bytes.Buffer{}
 	log := New(&dst).With().
@@ -497,3 +545,39 @@ func ExampleContext_Durs() {
 	fmt.Println(decodeIfBinaryToString(dst.Bytes()))
 	// Output: {"foo":"bar","durs":[10000,20000],"message":"hello world"}
 }
+
+func ExampleContext_Fields_map() {
+	fields := map[string]interface{}{
+		"bar": "baz",
+		"n":   1,
+	}
+
+	dst := bytes.Buffer{}
+	log := New(&dst).With().
+		Str("foo", "bar").
+		Fields(fields).
+		Logger()
+
+	log.Log().Msg("hello world")
+
+	fmt.Println(decodeIfBinaryToString(dst.Bytes()))
+	// Output: {"foo":"bar","bar":"baz","n":1,"message":"hello world"}
+}
+
+func ExampleContext_Fields_slice() {
+	fields := []interface{}{
+		"bar", "baz",
+		"n", 1,
+	}
+
+	dst := bytes.Buffer{}
+	log := New(&dst).With().
+		Str("foo", "bar").
+		Fields(fields).
+		Logger()
+
+	log.Log().Msg("hello world")
+
+	fmt.Println(decodeIfBinaryToString(dst.Bytes()))
+	// Output: {"foo":"bar","bar":"baz","n":1,"message":"hello world"}
+}

cmd/lint/README.md

@@ -1,5 +1,7 @@
 # Zerolog Lint
 
+**DEPRECATED: In favor of https://github.com/ykadowak/zerologlint which is integrated with `go vet` and [golangci-lint](https://golangci-lint.run/).**
+
 This is a basic linter that checks for missing log event finishers. Finds errors like: `log.Error().Int64("userID": 5)` - missing the `Msg`/`Msgf` finishers.
 
 ## Problem
@@ -27,7 +29,7 @@ The command accepts only one argument - the package to be inspected - and 4 opti
 - ignoreFile
     - which files to ignore, either by full path or by go path (package/file.go)
 - ignorePkg
-    - do not inspect the specified package if found in the dependecy tree
+    - do not inspect the specified package if found in the dependency tree
 - ignorePkgRecursively
     - do not inspect the specified package or its subpackages if found in the dependency tree
 

cmd/lint/go.mod

@@ -0,0 +1,5 @@
+module github.com/rs/zerolog/cmd/lint
+
+go 1.15
+
+require golang.org/x/tools v0.1.8

cmd/lint/go.sum

@@ -0,0 +1,28 @@
+github.com/yuin/goldmark v1.4.1/go.mod h1:mwnBkeHKe2W/ZEtQ+71ViKU8L12m81fl3OWwC1Zlc8k=
+golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
+golang.org/x/crypto v0.0.0-20191011191535-87dc89f01550/go.mod h1:yigFU9vqHzYiE8UmvKecakEJjdnWj3jj499lnFckfCI=
+golang.org/x/mod v0.5.1 h1:OJxoQ/rynoF0dcCdI7cLPktw/hR2cueqYfjm43oqK38=
+golang.org/x/mod v0.5.1/go.mod h1:5OXOZSfqPIIbmVBIIKWRFfZjPR0E5r58TLhUjH0a2Ro=
+golang.org/x/net v0.0.0-20190404232315-eb5bcb51f2a3/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
+golang.org/x/net v0.0.0-20190620200207-3b0461eec859/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
+golang.org/x/net v0.0.0-20211015210444-4f30a5c0130f/go.mod h1:9nx3DQGgdP8bBQD5qxJ1jj9UTztislL4KSBs9R2vV5Y=
+golang.org/x/sync v0.0.0-20190423024810-112230192c58/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
+golang.org/x/sync v0.0.0-20210220032951-036812b2e83c/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
+golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
+golang.org/x/sys v0.0.0-20190412213103-97732733099d/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20201119102817-f84b799fce68/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20210423082822-04245dca01da/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20211019181941-9d821ace8654 h1:id054HUawV2/6IGm2IV8KZQjqtwAOo2CYlOToYqa0d0=
+golang.org/x/sys v0.0.0-20211019181941-9d821ace8654/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/term v0.0.0-20201126162022-7de9c90e9dd1/go.mod h1:bj7SfCRtBDWHUb9snDiAeCFNEtKQo2Wmx5Cou7ajbmo=
+golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
+golang.org/x/text v0.3.6/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
+golang.org/x/text v0.3.7/go.mod h1:u+2+/6zg+i71rQMx5EYifcz6MCKuco9NR6JIITiCfzQ=
+golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
+golang.org/x/tools v0.0.0-20191119224855-298f0cb1881e/go.mod h1:b+2E5dAYhXwXZwtnZ6UAqBI28+e2cm9otk0dWdXHAEo=
+golang.org/x/tools v0.1.8 h1:P1HhGGuLW4aAclzjtmJdf0mJOjVUZUzOTqkAkWL+l6w=
+golang.org/x/tools v0.1.8/go.mod h1:nABZi5QlRsZVlzPpHl034qft6wpY4eDcsTt5AaioBiU=
+golang.org/x/xerrors v0.0.0-20190717185122-a985d3407aa7/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
+golang.org/x/xerrors v0.0.0-20191011141410-1b5146add898/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
+golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1 h1:go1bK/D/BFZV2I8cIQd1NKEZ+0owSTG1fDTci4IqFcE=
+golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=

cmd/prettylog/README.md

@@ -0,0 +1,40 @@
+# Zerolog PrettyLog
+
+This is a basic CLI utility that will colorize and pretty print your structured JSON logs.
+
+## Usage
+
+You can compile it or run it directly. The only issue is that by default Zerolog does not output to `stdout`
+but rather to `stderr` so we must pipe `stderr` stream to this CLI tool.
+
+### Linux
+
+These commands will redirect `stderr` to our `prettylog` tool and `stdout` will remain unaffected.
+
+1. Compiled version
+
+```shell
+some_program_with_zerolog 2> >(prettylog)
+```
+
+2. Run it directly with `go run`
+
+```shell
+some_program_with_zerolog 2> >(go run cmd/prettylog/prettylog.go)
+```
+
+### Windows
+
+These commands will redirect `stderr` to `stdout` and then pipe it to our `prettylog` tool.
+
+1. Compiled version
+
+```shell
+some_program_with_zerolog 2>&1 | prettylog
+```
+
+2. Run it directly with `go run`
+
+```shell
+some_program_with_zerolog 2>&1 | go run cmd/prettylog/prettylog.go
+```

cmd/prettylog/prettylog.go

@@ -0,0 +1,82 @@
+package main
+
+import (
+	"bufio"
+	"errors"
+	"flag"
+	"fmt"
+	"io"
+	"os"
+	"time"
+
+	"github.com/rs/zerolog"
+)
+
+func isInputFromPipe() bool {
+	fileInfo, _ := os.Stdin.Stat()
+	return fileInfo.Mode()&os.ModeCharDevice == 0
+}
+
+func processInput(reader io.Reader, writer io.Writer) error {
+	scanner := bufio.NewScanner(reader)
+	for scanner.Scan() {
+		bytesToWrite := scanner.Bytes()
+		_, err := writer.Write(bytesToWrite)
+		if err != nil {
+			if errors.Is(err, io.EOF) {
+				break
+			}
+
+			fmt.Printf("%s\n", bytesToWrite)
+		}
+	}
+
+	return scanner.Err()
+}
+
+func main() {
+	timeFormats := map[string]string{
+		"default": time.Kitchen,
+		"full":    time.RFC1123,
+	}
+
+	timeFormatFlag := flag.String(
+		"time-format",
+		"default",
+		"Time format, either 'default' or 'full'",
+	)
+
+	flag.Parse()
+
+	timeFormat, ok := timeFormats[*timeFormatFlag]
+	if !ok {
+		panic("Invalid time-format provided")
+	}
+
+	writer := zerolog.NewConsoleWriter()
+	writer.TimeFormat = timeFormat
+
+	if isInputFromPipe() {
+		_ = processInput(os.Stdin, writer)
+	} else if flag.NArg() >= 1 {
+		for _, filename := range flag.Args() {
+			// Scan each line from filename and write it into writer
+			reader, err := os.Open(filename)
+			if err != nil {
+				fmt.Printf("%s open: %v", filename, err)
+				os.Exit(1)
+			}
+
+			if err := processInput(reader, writer); err != nil {
+				fmt.Printf("%s scan: %v", filename, err)
+				os.Exit(1)
+			}
+		}
+	} else {
+		fmt.Println("Usage:")
+		fmt.Println("  app_with_zerolog | 2> >(prettylog)")
+		fmt.Println("  prettylog zerolog_output.jsonl")
+		os.Exit(1)
+		return
+	}
+}

console.go

@@ -6,16 +6,14 @@ import (
 	"fmt"
 	"io"
 	"os"
+	"path/filepath"
 	"sort"
 	"strconv"
 	"strings"
 	"sync"
 	"time"
-)
 
-const (
-	colorBold = iota + 1
-	colorFaint
+	"github.com/mattn/go-colorable"
 )
 
 const (
@@ -27,6 +25,11 @@ const (
 	colorMagenta
 	colorCyan
 	colorWhite
+
+	colorBold     = 1
+	colorDarkGray = 90
+
+	unknownLevel = "???"
 )
 
 var (
@@ -56,9 +59,24 @@ type ConsoleWriter struct {
 	// TimeFormat specifies the format for timestamp in output.
 	TimeFormat string
 
+	// TimeLocation tells ConsoleWriter’s default FormatTimestamp
+	// how to localize the time.
+	TimeLocation *time.Location
+
 	// PartsOrder defines the order of parts in output.
 	PartsOrder []string
 
+	// PartsExclude defines parts to not display in output.
+	PartsExclude []string
+
+	// FieldsOrder defines the order of contextual fields in output.
+	FieldsOrder []string
+
+	fieldIsOrdered map[string]int
+
+	// FieldsExclude defines contextual fields to not display in output.
+	FieldsExclude []string
+
 	FormatTimestamp     Formatter
 	FormatLevel         Formatter
 	FormatCaller        Formatter
@@ -67,25 +85,39 @@ type ConsoleWriter struct {
 	FormatFieldValue    Formatter
 	FormatErrFieldName  Formatter
 	FormatErrFieldValue Formatter
+
+	FormatExtra func(map[string]interface{}, *bytes.Buffer) error
+
+	FormatPrepare func(map[string]interface{}) error
 }
 
 // NewConsoleWriter creates and initializes a new ConsoleWriter.
 func NewConsoleWriter(options ...func(w *ConsoleWriter)) ConsoleWriter {
 	w := ConsoleWriter{
-		Out:        os.Stdout,
-		TimeFormat: consoleDefaultTimeFormat,
-		PartsOrder: consoleDefaultPartsOrder(),
+		Out:          os.Stdout,
+		TimeFormat:   consoleDefaultTimeFormat,
+		PartsOrder:   consoleDefaultPartsOrder(),
 	}
 
 	for _, opt := range options {
 		opt(&w)
 	}
 
+	// Fix color on Windows
+	if w.Out == os.Stdout || w.Out == os.Stderr {
+		w.Out = colorable.NewColorable(w.Out.(*os.File))
+	}
+
 	return w
 }
 
 // Write transforms the JSON input with formatters and appends to w.Out.
 func (w ConsoleWriter) Write(p []byte) (n int, err error) {
+	// Fix color on Windows
+	if w.Out == os.Stdout || w.Out == os.Stderr {
+		w.Out = colorable.NewColorable(w.Out.(*os.File))
+	}
+
 	if w.PartsOrder == nil {
 		w.PartsOrder = consoleDefaultPartsOrder()
 	}
@@ -105,33 +137,74 @@ func (w ConsoleWriter) Write(p []byte) (n int, err error) {
 		return n, fmt.Errorf("cannot decode event: %s", err)
 	}
 
+	if w.FormatPrepare != nil {
+		err = w.FormatPrepare(evt)
+		if err != nil {
+			return n, err
+		}
+	}
+
 	for _, p := range w.PartsOrder {
 		w.writePart(buf, evt, p)
 	}
 
 	w.writeFields(evt, buf)
 
+	if w.FormatExtra != nil {
+		err = w.FormatExtra(evt, buf)
+		if err != nil {
+			return n, err
+		}
+	}
+
 	err = buf.WriteByte('\n')
 	if err != nil {
 		return n, err
 	}
+
 	_, err = buf.WriteTo(w.Out)
 	return len(p), err
 }
 
+// Call the underlying writer's Close method if it is an io.Closer. Otherwise
+// does nothing.
+func (w ConsoleWriter) Close() error {
+	if closer, ok := w.Out.(io.Closer); ok {
+		return closer.Close()
+	}
+	return nil
+}
+
 // writeFields appends formatted key-value pairs to buf.
 func (w ConsoleWriter) writeFields(evt map[string]interface{}, buf *bytes.Buffer) {
 	var fields = make([]string, 0, len(evt))
 	for field := range evt {
+		var isExcluded bool
+		for _, excluded := range w.FieldsExclude {
+			if field == excluded {
+				isExcluded = true
+				break
+			}
+		}
+		if isExcluded {
+			continue
+		}
+
 		switch field {
 		case LevelFieldName, TimestampFieldName, MessageFieldName, CallerFieldName:
 			continue
 		}
 		fields = append(fields, field)
 	}
-	sort.Strings(fields)
 
-	if len(fields) > 0 {
+	if len(w.FieldsOrder) > 0 {
+		w.orderFields(fields)
+	} else {
+		sort.Strings(fields)
+	}
+
+	// Write space only if something has already been written to the buffer, and if there are fields.
+	if buf.Len() > 0 && len(fields) > 0 {
 		buf.WriteByte(' ')
 	}
 
@@ -192,7 +265,7 @@ func (w ConsoleWriter) writeFields(evt map[string]interface{}, buf *bytes.Buffer
 		case json.Number:
 			buf.WriteString(fv(fValue))
 		default:
-			b, err := json.Marshal(fValue)
+			b, err := InterfaceMarshalFunc(fValue)
 			if err != nil {
 				fmt.Fprintf(buf, colorize("[error: %v]", colorRed, w.NoColor), err)
 			} else {
@@ -210,6 +283,14 @@ func (w ConsoleWriter) writeFields(evt map[string]interface{}, buf *bytes.Buffer
 func (w ConsoleWriter) writePart(buf *bytes.Buffer, evt map[string]interface{}, p string) {
 	var f Formatter
 
+	if w.PartsExclude != nil && len(w.PartsExclude) > 0 {
+		for _, exclude := range w.PartsExclude {
+			if exclude == p {
+				return
+			}
+		}
+	}
+
 	switch p {
 	case LevelFieldName:
 		if w.FormatLevel == nil {
@@ -219,13 +300,13 @@ func (w ConsoleWriter) writePart(buf *bytes.Buffer, evt map[string]interface{},
 		}
 	case TimestampFieldName:
 		if w.FormatTimestamp == nil {
-			f = consoleDefaultFormatTimestamp(w.TimeFormat, w.NoColor)
+			f = consoleDefaultFormatTimestamp(w.TimeFormat, w.TimeLocation, w.NoColor)
 		} else {
 			f = w.FormatTimestamp
 		}
 	case MessageFieldName:
 		if w.FormatMessage == nil {
-			f = consoleDefaultFormatMessage
+			f = consoleDefaultFormatMessage(w.NoColor, evt[LevelFieldName])
 		} else {
 			f = w.FormatMessage
 		}
@@ -246,11 +327,37 @@ func (w ConsoleWriter) writePart(buf *bytes.Buffer, evt map[string]interface{},
 	var s = f(evt[p])
 
 	if len(s) > 0 {
+		if buf.Len() > 0 {
+			buf.WriteByte(' ') // Write space only if not the first part
+		}
 		buf.WriteString(s)
-		if p != w.PartsOrder[len(w.PartsOrder)-1] { // Skip space for last part
-			buf.WriteByte(' ')
+	}
+}
+
+// orderFields takes an array of field names and an array representing field order
+// and returns an array with any ordered fields at the beginning, in order,
+// and the remaining fields after in their original order.
+func (w ConsoleWriter) orderFields(fields []string) {
+	if w.fieldIsOrdered == nil {
+		w.fieldIsOrdered = make(map[string]int)
+		for i, fieldName := range w.FieldsOrder {
+			w.fieldIsOrdered[fieldName] = i
 		}
 	}
+	sort.Slice(fields, func(i, j int) bool {
+		ii, iOrdered := w.fieldIsOrdered[fields[i]]
+		jj, jOrdered := w.fieldIsOrdered[fields[j]]
+		if iOrdered && jOrdered {
+			return ii < jj
+		}
+		if iOrdered {
+			return true
+		}
+		if jOrdered {
+			return false
+		}
+		return fields[i] < fields[j]
+	})
 }
 
 // needsQuote returns true when the string s should be quoted in output.
@@ -263,8 +370,13 @@ func needsQuote(s string) bool {
 	return false
 }
 
-// colorize returns the string s wrapped in ANSI code c, unless disabled is true.
+// colorize returns the string s wrapped in ANSI code c, unless disabled is true or c is 0.
 func colorize(s interface{}, c int, disabled bool) string {
+	e := os.Getenv("NO_COLOR")
+	if e != "" || c == 0 {
+		disabled = true
+	}
+
 	if disabled {
 		return fmt.Sprintf("%s", s)
 	}
@@ -282,51 +394,74 @@ func consoleDefaultPartsOrder() []string {
 	}
 }
 
-func consoleDefaultFormatTimestamp(timeFormat string, noColor bool) Formatter {
+func consoleDefaultFormatTimestamp(timeFormat string, location *time.Location, noColor bool) Formatter {
 	if timeFormat == "" {
 		timeFormat = consoleDefaultTimeFormat
 	}
+	if location == nil {
+		location = time.Local
+	}
+
 	return func(i interface{}) string {
 		t := "<nil>"
 		switch tt := i.(type) {
 		case string:
-			ts, err := time.Parse(TimeFieldFormat, tt)
+			ts, err := time.ParseInLocation(TimeFieldFormat, tt, location)
 			if err != nil {
 				t = tt
 			} else {
-				t = ts.Format(timeFormat)
+				t = ts.In(location).Format(timeFormat)
 			}
 		case json.Number:
-			t = tt.String()
+			i, err := tt.Int64()
+			if err != nil {
+				t = tt.String()
+			} else {
+				var sec, nsec int64
+
+				switch TimeFieldFormat {
+				case TimeFormatUnixNano:
+					sec, nsec = 0, i
+				case TimeFormatUnixMicro:
+					sec, nsec = 0, int64(time.Duration(i)*time.Microsecond)
+				case TimeFormatUnixMs:
+					sec, nsec = 0, int64(time.Duration(i)*time.Millisecond)
+				default:
+					sec, nsec = i, 0
+				}
+
+				ts := time.Unix(sec, nsec)
+				t = ts.In(location).Format(timeFormat)
+			}
 		}
-		return colorize(t, colorFaint, noColor)
+		return colorize(t, colorDarkGray, noColor)
 	}
 }
 
+func stripLevel(ll string) string {
+	if len(ll) == 0 {
+		return unknownLevel
+	}
+	if len(ll) > 3 {
+		ll = ll[:3]
+	}
+	return strings.ToUpper(ll)
+}
+
 func consoleDefaultFormatLevel(noColor bool) Formatter {
 	return func(i interface{}) string {
-		var l string
 		if ll, ok := i.(string); ok {
-			switch ll {
-			case "debug":
-				l = colorize("DBG", colorYellow, noColor)
-			case "info":
-				l = colorize("INF", colorGreen, noColor)
-			case "warn":
-				l = colorize("WRN", colorRed, noColor)
-			case "error":
-				l = colorize(colorize("ERR", colorRed, noColor), colorBold, noColor)
-			case "fatal":
-				l = colorize(colorize("FTL", colorRed, noColor), colorBold, noColor)
-			case "panic":
-				l = colorize(colorize("PNC", colorRed, noColor), colorBold, noColor)
-			default:
-				l = colorize("???", colorBold, noColor)
+			level, _ := ParseLevel(ll)
+			fl, ok := FormattedLevels[level]
+			if ok {
+				return colorize(fl, LevelColors[level], noColor)
 			}
-		} else {
-			l = strings.ToUpper(fmt.Sprintf("%s", i))[0:3]
+			return stripLevel(ll)
 		}
-		return l
+		if i == nil {
+			return unknownLevel
+		}
+		return stripLevel(fmt.Sprintf("%s", i))
 	}
 }
 
@@ -337,24 +472,34 @@ func consoleDefaultFormatCaller(noColor bool) Formatter {
 			c = cc
 		}
 		if len(c) > 0 {
-			cwd, err := os.Getwd()
-			if err == nil {
-				c = strings.TrimPrefix(c, cwd)
-				c = strings.TrimPrefix(c, "/")
+			if cwd, err := os.Getwd(); err == nil {
+				if rel, err := filepath.Rel(cwd, c); err == nil {
+					c = rel
+				}
 			}
-			c = colorize(c, colorBold, noColor) + colorize(" >", colorFaint, noColor)
+			c = colorize(c, colorBold, noColor) + colorize(" >", colorCyan, noColor)
 		}
 		return c
 	}
 }
 
-func consoleDefaultFormatMessage(i interface{}) string {
-	return fmt.Sprintf("%s", i)
+func consoleDefaultFormatMessage(noColor bool, level interface{}) Formatter {
+	return func(i interface{}) string {
+		if i == nil || i == "" {
+			return ""
+		}
+		switch level {
+		case LevelInfoValue, LevelWarnValue, LevelErrorValue, LevelFatalValue, LevelPanicValue:
+			return colorize(fmt.Sprintf("%s", i), colorBold, noColor)
+		default:
+			return fmt.Sprintf("%s", i)
+		}
+	}
 }
 
 func consoleDefaultFormatFieldName(noColor bool) Formatter {
 	return func(i interface{}) string {
-		return colorize(fmt.Sprintf("%s=", i), colorFaint, noColor)
+		return colorize(fmt.Sprintf("%s=", i), colorCyan, noColor)
 	}
 }
 
@@ -364,12 +509,12 @@ func consoleDefaultFormatFieldValue(i interface{}) string {
 
 func consoleDefaultFormatErrFieldName(noColor bool) Formatter {
 	return func(i interface{}) string {
-		return colorize(fmt.Sprintf("%s=", i), colorRed, noColor)
+		return colorize(fmt.Sprintf("%s=", i), colorCyan, noColor)
 	}
 }
 
 func consoleDefaultFormatErrFieldValue(noColor bool) Formatter {
 	return func(i interface{}) string {
-		return colorize(fmt.Sprintf("%s", i), colorRed, noColor)
+		return colorize(colorize(fmt.Sprintf("%s", i), colorBold, noColor), colorRed, noColor)
 	}
 }

console_test.go

@@ -3,7 +3,7 @@ package zerolog_test
 import (
 	"bytes"
 	"fmt"
-	"io/ioutil"
+	"io"
 	"os"
 	"strings"
 	"testing"
@@ -76,7 +76,7 @@ func TestConsoleWriter(t *testing.T) {
 		buf := &bytes.Buffer{}
 		w := zerolog.ConsoleWriter{Out: buf, NoColor: true, PartsOrder: []string{"foo"}}
 
-		_, err := w.Write([]byte(`{"foo" : "DEFAULT"}`))
+		_, err := w.Write([]byte(`{"foo": "DEFAULT"}`))
 		if err != nil {
 			t.Errorf("Unexpected error when writing output: %s", err)
 		}
@@ -92,29 +92,163 @@ func TestConsoleWriter(t *testing.T) {
 		buf := &bytes.Buffer{}
 		w := zerolog.ConsoleWriter{Out: buf, NoColor: false}
 
-		_, err := w.Write([]byte(`{"level" : "warn", "message" : "Foobar"}`))
+		_, err := w.Write([]byte(`{"level": "warn", "message": "Foobar"}`))
 		if err != nil {
 			t.Errorf("Unexpected error when writing output: %s", err)
 		}
 
-		expectedOutput := "\x1b[2m<nil>\x1b[0m \x1b[31mWRN\x1b[0m Foobar\n"
+		expectedOutput := "\x1b[90m<nil>\x1b[0m \x1b[33mWRN\x1b[0m \x1b[1mFoobar\x1b[0m\n"
 		actualOutput := buf.String()
 		if actualOutput != expectedOutput {
 			t.Errorf("Unexpected output %q, want: %q", actualOutput, expectedOutput)
 		}
 	})
 
-	t.Run("Write fields", func(t *testing.T) {
-		buf := &bytes.Buffer{}
-		w := zerolog.ConsoleWriter{Out: buf, NoColor: true}
+	t.Run("NO_COLOR = true", func(t *testing.T) {
+		os.Setenv("NO_COLOR", "anything")
 
-		d := time.Unix(0, 0).UTC().Format(time.RFC3339)
-		_, err := w.Write([]byte(`{"time" : "` + d + `", "level" : "debug", "message" : "Foobar", "foo" : "bar"}`))
+		buf := &bytes.Buffer{}
+		w := zerolog.ConsoleWriter{Out: buf}
+
+		_, err := w.Write([]byte(`{"level": "warn", "message": "Foobar"}`))
 		if err != nil {
 			t.Errorf("Unexpected error when writing output: %s", err)
 		}
 
-		expectedOutput := "12:00AM DBG Foobar foo=bar\n"
+		expectedOutput := "<nil> WRN Foobar\n"
+		actualOutput := buf.String()
+		if actualOutput != expectedOutput {
+			t.Errorf("Unexpected output %q, want: %q", actualOutput, expectedOutput)
+		}
+		os.Unsetenv("NO_COLOR")
+	})
+
+	t.Run("Write fields", func(t *testing.T) {
+		buf := &bytes.Buffer{}
+		w := zerolog.ConsoleWriter{Out: buf, NoColor: true}
+
+		ts := time.Unix(0, 0)
+		d := ts.UTC().Format(time.RFC3339)
+		_, err := w.Write([]byte(`{"time": "` + d + `", "level": "debug", "message": "Foobar", "foo": "bar"}`))
+		if err != nil {
+			t.Errorf("Unexpected error when writing output: %s", err)
+		}
+
+		expectedOutput := ts.Format(time.Kitchen) + " DBG Foobar foo=bar\n"
+		actualOutput := buf.String()
+		if actualOutput != expectedOutput {
+			t.Errorf("Unexpected output %q, want: %q", actualOutput, expectedOutput)
+		}
+	})
+
+	t.Run("Unix timestamp input format", func(t *testing.T) {
+		of := zerolog.TimeFieldFormat
+		defer func() {
+			zerolog.TimeFieldFormat = of
+		}()
+		zerolog.TimeFieldFormat = zerolog.TimeFormatUnix
+
+		buf := &bytes.Buffer{}
+		w := zerolog.ConsoleWriter{Out: buf, TimeFormat: time.StampMilli, NoColor: true}
+
+		_, err := w.Write([]byte(`{"time": 1234, "level": "debug", "message": "Foobar", "foo": "bar"}`))
+		if err != nil {
+			t.Errorf("Unexpected error when writing output: %s", err)
+		}
+
+		expectedOutput := time.Unix(1234, 0).Format(time.StampMilli) + " DBG Foobar foo=bar\n"
+		actualOutput := buf.String()
+		if actualOutput != expectedOutput {
+			t.Errorf("Unexpected output %q, want: %q", actualOutput, expectedOutput)
+		}
+	})
+
+	t.Run("Unix timestamp ms input format", func(t *testing.T) {
+		of := zerolog.TimeFieldFormat
+		defer func() {
+			zerolog.TimeFieldFormat = of
+		}()
+		zerolog.TimeFieldFormat = zerolog.TimeFormatUnixMs
+
+		buf := &bytes.Buffer{}
+		w := zerolog.ConsoleWriter{Out: buf, TimeFormat: time.StampMilli, NoColor: true}
+
+		_, err := w.Write([]byte(`{"time": 1234567, "level": "debug", "message": "Foobar", "foo": "bar"}`))
+		if err != nil {
+			t.Errorf("Unexpected error when writing output: %s", err)
+		}
+
+		expectedOutput := time.Unix(1234, 567000000).Format(time.StampMilli) + " DBG Foobar foo=bar\n"
+		actualOutput := buf.String()
+		if actualOutput != expectedOutput {
+			t.Errorf("Unexpected output %q, want: %q", actualOutput, expectedOutput)
+		}
+	})
+
+	t.Run("Unix timestamp us input format", func(t *testing.T) {
+		of := zerolog.TimeFieldFormat
+		defer func() {
+			zerolog.TimeFieldFormat = of
+		}()
+		zerolog.TimeFieldFormat = zerolog.TimeFormatUnixMicro
+
+		buf := &bytes.Buffer{}
+		w := zerolog.ConsoleWriter{Out: buf, TimeFormat: time.StampMicro, NoColor: true}
+
+		_, err := w.Write([]byte(`{"time": 1234567891, "level": "debug", "message": "Foobar", "foo": "bar"}`))
+		if err != nil {
+			t.Errorf("Unexpected error when writing output: %s", err)
+		}
+
+		expectedOutput := time.Unix(1234, 567891000).Format(time.StampMicro) + " DBG Foobar foo=bar\n"
+		actualOutput := buf.String()
+		if actualOutput != expectedOutput {
+			t.Errorf("Unexpected output %q, want: %q", actualOutput, expectedOutput)
+		}
+	})
+
+	t.Run("No message field", func(t *testing.T) {
+		buf := &bytes.Buffer{}
+		w := zerolog.ConsoleWriter{Out: buf, NoColor: true}
+
+		_, err := w.Write([]byte(`{"level": "debug", "foo": "bar"}`))
+		if err != nil {
+			t.Errorf("Unexpected error when writing output: %s", err)
+		}
+
+		expectedOutput := "<nil> DBG foo=bar\n"
+		actualOutput := buf.String()
+		if actualOutput != expectedOutput {
+			t.Errorf("Unexpected output %q, want: %q", actualOutput, expectedOutput)
+		}
+	})
+
+	t.Run("No level field", func(t *testing.T) {
+		buf := &bytes.Buffer{}
+		w := zerolog.ConsoleWriter{Out: buf, NoColor: true}
+
+		_, err := w.Write([]byte(`{"message": "Foobar", "foo": "bar"}`))
+		if err != nil {
+			t.Errorf("Unexpected error when writing output: %s", err)
+		}
+
+		expectedOutput := "<nil> ??? Foobar foo=bar\n"
+		actualOutput := buf.String()
+		if actualOutput != expectedOutput {
+			t.Errorf("Unexpected output %q, want: %q", actualOutput, expectedOutput)
+		}
+	})
+
+	t.Run("Write colorized fields", func(t *testing.T) {
+		buf := &bytes.Buffer{}
+		w := zerolog.ConsoleWriter{Out: buf, NoColor: false}
+
+		_, err := w.Write([]byte(`{"level": "warn", "message": "Foobar", "foo": "bar"}`))
+		if err != nil {
+			t.Errorf("Unexpected error when writing output: %s", err)
+		}
+
+		expectedOutput := "\x1b[90m<nil>\x1b[0m \x1b[33mWRN\x1b[0m \x1b[1mFoobar\x1b[0m \x1b[36mfoo=\x1b[0mbar\n"
 		actualOutput := buf.String()
 		if actualOutput != expectedOutput {
 			t.Errorf("Unexpected output %q, want: %q", actualOutput, expectedOutput)
@@ -125,8 +259,9 @@ func TestConsoleWriter(t *testing.T) {
 		buf := &bytes.Buffer{}
 		w := zerolog.ConsoleWriter{Out: buf, NoColor: true}
 
-		d := time.Unix(0, 0).UTC().Format(time.RFC3339)
-		evt := `{"time" : "` + d + `", "level" : "error", "message" : "Foobar", "aaa" : "bbb", "error" : "Error"}`
+		ts := time.Unix(0, 0)
+		d := ts.UTC().Format(time.RFC3339)
+		evt := `{"time": "` + d + `", "level": "error", "message": "Foobar", "aaa": "bbb", "error": "Error"}`
 		// t.Log(evt)
 
 		_, err := w.Write([]byte(evt))
@@ -134,7 +269,7 @@ func TestConsoleWriter(t *testing.T) {
 			t.Errorf("Unexpected error when writing output: %s", err)
 		}
 
-		expectedOutput := "12:00AM ERR Foobar error=Error aaa=bbb\n"
+		expectedOutput := ts.Format(time.Kitchen) + " ERR Foobar error=Error aaa=bbb\n"
 		actualOutput := buf.String()
 		if actualOutput != expectedOutput {
 			t.Errorf("Unexpected output %q, want: %q", actualOutput, expectedOutput)
@@ -150,8 +285,9 @@ func TestConsoleWriter(t *testing.T) {
 			t.Fatalf("Cannot get working directory: %s", err)
 		}
 
-		d := time.Unix(0, 0).UTC().Format(time.RFC3339)
-		evt := `{"time" : "` + d + `", "level" : "debug", "message" : "Foobar", "foo" : "bar", "caller" : "` + cwd + `/foo/bar.go"}`
+		ts := time.Unix(0, 0)
+		d := ts.UTC().Format(time.RFC3339)
+		evt := `{"time": "` + d + `", "level": "debug", "message": "Foobar", "foo": "bar", "caller": "` + cwd + `/foo/bar.go"}`
 		// t.Log(evt)
 
 		_, err = w.Write([]byte(evt))
@@ -159,7 +295,7 @@ func TestConsoleWriter(t *testing.T) {
 			t.Errorf("Unexpected error when writing output: %s", err)
 		}
 
-		expectedOutput := "12:00AM DBG foo/bar.go > Foobar foo=bar\n"
+		expectedOutput := ts.Format(time.Kitchen) + " DBG foo/bar.go > Foobar foo=bar\n"
 		actualOutput := buf.String()
 		if actualOutput != expectedOutput {
 			t.Errorf("Unexpected output %q, want: %q", actualOutput, expectedOutput)
@@ -170,7 +306,7 @@ func TestConsoleWriter(t *testing.T) {
 		buf := &bytes.Buffer{}
 		w := zerolog.ConsoleWriter{Out: buf, NoColor: true}
 
-		evt := `{"level" : "debug", "message" : "Foobar", "foo" : [1, 2, 3], "bar" : true}`
+		evt := `{"level": "debug", "message": "Foobar", "foo": [1, 2, 3], "bar": true}`
 		// t.Log(evt)
 
 		_, err := w.Write([]byte(evt))
@@ -184,6 +320,85 @@ func TestConsoleWriter(t *testing.T) {
 			t.Errorf("Unexpected output %q, want: %q", actualOutput, expectedOutput)
 		}
 	})
+
+	t.Run("With an extra 'level' field", func(t *testing.T) {
+		t.Run("malformed string", func(t *testing.T) {
+			cases := []struct {
+				field  string
+				output string
+			}{
+				{"", "<nil> ??? Hello World foo=bar\n"},
+				{"-", "<nil> - Hello World foo=bar\n"},
+				{"1", "<nil> " + zerolog.FormattedLevels[1] + " Hello World foo=bar\n"},
+				{"a", "<nil> A Hello World foo=bar\n"},
+				{"12", "<nil> 12 Hello World foo=bar\n"},
+				{"a2", "<nil> A2 Hello World foo=bar\n"},
+				{"2a", "<nil> 2A Hello World foo=bar\n"},
+				{"ab", "<nil> AB Hello World foo=bar\n"},
+				{"12a", "<nil> 12A Hello World foo=bar\n"},
+				{"a12", "<nil> A12 Hello World foo=bar\n"},
+				{"abc", "<nil> ABC Hello World foo=bar\n"},
+				{"123", "<nil> 123 Hello World foo=bar\n"},
+				{"abcd", "<nil> ABC Hello World foo=bar\n"},
+				{"1234", "<nil> 123 Hello World foo=bar\n"},
+				{"123d", "<nil> 123 Hello World foo=bar\n"},
+				{"01", "<nil> " + zerolog.FormattedLevels[1] + " Hello World foo=bar\n"},
+				{"001", "<nil> " + zerolog.FormattedLevels[1] + " Hello World foo=bar\n"},
+				{"0001", "<nil> " + zerolog.FormattedLevels[1] + " Hello World foo=bar\n"},
+			}
+			for i, c := range cases {
+				c := c
+				t.Run(fmt.Sprintf("case %d", i), func(t *testing.T) {
+					buf := &bytes.Buffer{}
+					out := zerolog.NewConsoleWriter()
+					out.NoColor = true
+					out.Out = buf
+					log := zerolog.New(out)
+
+					log.Debug().Str("level", c.field).Str("foo", "bar").Msg("Hello World")
+
+					actualOutput := buf.String()
+					if actualOutput != c.output {
+						t.Errorf("Unexpected output %q, want: %q", actualOutput, c.output)
+					}
+				})
+			}
+		})
+
+		t.Run("weird value", func(t *testing.T) {
+			cases := []struct {
+				field  interface{}
+				output string
+			}{
+				{0, "<nil> 0 Hello World foo=bar\n"},
+				{1, "<nil> 1 Hello World foo=bar\n"},
+				{-1, "<nil> -1 Hello World foo=bar\n"},
+				{-3, "<nil> -3 Hello World foo=bar\n"},
+				{-32, "<nil> -32 Hello World foo=bar\n"},
+				{-321, "<nil> -32 Hello World foo=bar\n"},
+				{12, "<nil> 12 Hello World foo=bar\n"},
+				{123, "<nil> 123 Hello World foo=bar\n"},
+				{1234, "<nil> 123 Hello World foo=bar\n"},
+			}
+			for i, c := range cases {
+				c := c
+				t.Run(fmt.Sprintf("case %d", i), func(t *testing.T) {
+					buf := &bytes.Buffer{}
+					out := zerolog.NewConsoleWriter()
+					out.NoColor = true
+					out.Out = buf
+					log := zerolog.New(out)
+
+					log.Debug().Interface("level", c.field).Str("foo", "bar").Msg("Hello World")
+
+					actualOutput := buf.String()
+					if actualOutput != c.output {
+						t.Errorf("Unexpected output %q, want: %q", actualOutput, c.output)
+					}
+				})
+			}
+		})
+	})
 }
 
 func TestConsoleWriterConfiguration(t *testing.T) {
@@ -191,26 +406,56 @@ func TestConsoleWriterConfiguration(t *testing.T) {
 		buf := &bytes.Buffer{}
 		w := zerolog.ConsoleWriter{Out: buf, NoColor: true, TimeFormat: time.RFC3339}
 
-		d := time.Unix(0, 0).UTC().Format(time.RFC3339)
-		evt := `{"time" : "` + d + `", "level" : "info", "message" : "Foobar"}`
+		ts := time.Unix(0, 0)
+		d := ts.UTC().Format(time.RFC3339)
+		evt := `{"time": "` + d + `", "level": "info", "message": "Foobar"}`
 
 		_, err := w.Write([]byte(evt))
 		if err != nil {
 			t.Errorf("Unexpected error when writing output: %s", err)
 		}
 
-		expectedOutput := "1970-01-01T00:00:00Z INF Foobar\n"
+		expectedOutput := ts.Format(time.RFC3339) + " INF Foobar\n"
 		actualOutput := buf.String()
 		if actualOutput != expectedOutput {
 			t.Errorf("Unexpected output %q, want: %q", actualOutput, expectedOutput)
 		}
 	})
 
+	t.Run("Sets TimeFormat and TimeLocation", func(t *testing.T) {
+		locs := []*time.Location{ time.Local, time.UTC }
+
+		for _, location := range locs {
+			buf := &bytes.Buffer{}
+			w := zerolog.ConsoleWriter{
+				Out: buf,
+				NoColor: true,
+				TimeFormat: time.RFC3339,
+				TimeLocation: location,
+			}
+
+			ts := time.Unix(0, 0)
+			d := ts.UTC().Format(time.RFC3339)
+			evt := `{"time": "` + d + `", "level": "info", "message": "Foobar"}`
+
+			_, err := w.Write([]byte(evt))
+			if err != nil {
+				t.Errorf("Unexpected error when writing output: %s", err)
+			}
+
+			expectedOutput := ts.In(location).Format(time.RFC3339) + " INF Foobar\n"
+			actualOutput := buf.String()
+			if actualOutput != expectedOutput {
+				t.Errorf("Unexpected output %q, want: %q (location=%s)", actualOutput, expectedOutput, location)
+			}
+		}
+	})
+
 	t.Run("Sets PartsOrder", func(t *testing.T) {
 		buf := &bytes.Buffer{}
 		w := zerolog.ConsoleWriter{Out: buf, NoColor: true, PartsOrder: []string{"message", "level"}}
 
-		evt := `{"level" : "info", "message" : "Foobar"}`
+		evt := `{"level": "info", "message": "Foobar"}`
 		_, err := w.Write([]byte(evt))
 		if err != nil {
 			t.Errorf("Unexpected error when writing output: %s", err)
@@ -222,15 +467,139 @@ func TestConsoleWriterConfiguration(t *testing.T) {
 			t.Errorf("Unexpected output %q, want: %q", actualOutput, expectedOutput)
 		}
 	})
+
+	t.Run("Sets PartsExclude", func(t *testing.T) {
+		buf := &bytes.Buffer{}
+		w := zerolog.ConsoleWriter{Out: buf, NoColor: true, PartsExclude: []string{"time"}}
+
+		d := time.Unix(0, 0).UTC().Format(time.RFC3339)
+		evt := `{"time": "` + d + `", "level": "info", "message": "Foobar"}`
+		_, err := w.Write([]byte(evt))
+		if err != nil {
+			t.Errorf("Unexpected error when writing output: %s", err)
+		}
+
+		expectedOutput := "INF Foobar\n"
+		actualOutput := buf.String()
+		if actualOutput != expectedOutput {
+			t.Errorf("Unexpected output %q, want: %q", actualOutput, expectedOutput)
+		}
+	})
+
+	t.Run("Sets FieldsOrder", func(t *testing.T) {
+		buf := &bytes.Buffer{}
+		w := zerolog.ConsoleWriter{Out: buf, NoColor: true, FieldsOrder: []string{"zebra", "aardvark"}}
+
+		evt := `{"level": "info", "message": "Zoo", "aardvark": "Able", "mussel": "Mountain", "zebra": "Zulu"}`
+		_, err := w.Write([]byte(evt))
+		if err != nil {
+			t.Errorf("Unexpected error when writing output: %s", err)
+		}
+
+		expectedOutput := "<nil> INF Zoo zebra=Zulu aardvark=Able mussel=Mountain\n"
+		actualOutput := buf.String()
+		if actualOutput != expectedOutput {
+			t.Errorf("Unexpected output %q, want: %q", actualOutput, expectedOutput)
+		}
+	})
+
+	t.Run("Sets FieldsExclude", func(t *testing.T) {
+		buf := &bytes.Buffer{}
+		w := zerolog.ConsoleWriter{Out: buf, NoColor: true, FieldsExclude: []string{"foo"}}
+
+		evt := `{"level": "info", "message": "Foobar", "foo":"bar", "baz":"quux"}`
+		_, err := w.Write([]byte(evt))
+		if err != nil {
+			t.Errorf("Unexpected error when writing output: %s", err)
+		}
+
+		expectedOutput := "<nil> INF Foobar baz=quux\n"
+		actualOutput := buf.String()
+		if actualOutput != expectedOutput {
+			t.Errorf("Unexpected output %q, want: %q", actualOutput, expectedOutput)
+		}
+	})
+
+	t.Run("Sets FormatExtra", func(t *testing.T) {
+		buf := &bytes.Buffer{}
+		w := zerolog.ConsoleWriter{
+			Out: buf, NoColor: true, PartsOrder: []string{"level", "message"},
+			FormatExtra: func(evt map[string]interface{}, buf *bytes.Buffer) error {
+				buf.WriteString("\nAdditional stacktrace")
+				return nil
+			},
+		}
+
+		evt := `{"level": "info", "message": "Foobar"}`
+		_, err := w.Write([]byte(evt))
+		if err != nil {
+			t.Errorf("Unexpected error when writing output: %s", err)
+		}
+
+		expectedOutput := "INF Foobar\nAdditional stacktrace\n"
+		actualOutput := buf.String()
+		if actualOutput != expectedOutput {
+			t.Errorf("Unexpected output %q, want: %q", actualOutput, expectedOutput)
+		}
+	})
+
+	t.Run("Sets FormatPrepare", func(t *testing.T) {
+		buf := &bytes.Buffer{}
+		w := zerolog.ConsoleWriter{
+			Out: buf, NoColor: true, PartsOrder: []string{"level", "message"},
+			FormatPrepare: func(evt map[string]interface{}) error {
+				evt["message"] = fmt.Sprintf("msg=%s", evt["message"])
+				return nil
+			},
+		}
+
+		evt := `{"level": "info", "message": "Foobar"}`
+		_, err := w.Write([]byte(evt))
+		if err != nil {
+			t.Errorf("Unexpected error when writing output: %s", err)
+		}
+
+		expectedOutput := "INF msg=Foobar\n"
+		actualOutput := buf.String()
+		if actualOutput != expectedOutput {
+			t.Errorf("Unexpected output %q, want: %q", actualOutput, expectedOutput)
+		}
+	})
+
+	t.Run("Uses local time for console writer without time zone", func(t *testing.T) {
+		// Regression test for issue #483 (check there for more details)
+
+		timeFormat := "2006-01-02 15:04:05"
+		expectedOutput := "2022-10-20 20:24:50 INF Foobar\n"
+		evt := `{"time": "2022-10-20 20:24:50", "level": "info", "message": "Foobar"}`
+
+		of := zerolog.TimeFieldFormat
+		defer func() {
+			zerolog.TimeFieldFormat = of
+		}()
+		zerolog.TimeFieldFormat = timeFormat
+
+		buf := &bytes.Buffer{}
+		w := zerolog.ConsoleWriter{Out: buf, NoColor: true, TimeFormat: timeFormat}
+		_, err := w.Write([]byte(evt))
+		if err != nil {
+			t.Errorf("Unexpected error when writing output: %s", err)
+		}
+
+		actualOutput := buf.String()
+		if actualOutput != expectedOutput {
+			t.Errorf("Unexpected output %q, want: %q", actualOutput, expectedOutput)
+		}
+	})
 }
 
 func BenchmarkConsoleWriter(b *testing.B) {
 	b.ResetTimer()
 	b.ReportAllocs()
 
-	var msg = []byte(`{"level" : "info", "foo" : "bar", "message" : "HELLO", "time" : "1990-01-01"}`)
+	var msg = []byte(`{"level": "info", "foo": "bar", "message": "HELLO", "time": "1990-01-01"}`)
 
-	w := zerolog.ConsoleWriter{Out: ioutil.Discard, NoColor: false}
+	w := zerolog.ConsoleWriter{Out: io.Discard, NoColor: false}
 
 	for i := 0; i < b.N; i++ {
 		w.Write(msg)

context.go

@@ -1,7 +1,10 @@
 package zerolog
 
 import (
-	"io/ioutil"
+	"context"
+	"fmt"
+	"io"
+	"math"
 	"net"
 	"time"
 )
@@ -16,9 +19,11 @@ func (c Context) Logger() Logger {
 	return c.l
 }
 
-// Fields is a helper function to use a map to set fields using type assertion.
-func (c Context) Fields(fields map[string]interface{}) Context {
-	c.l.context = appendFields(c.l.context, fields)
+// Fields is a helper function to use a map or slice to set fields using type assertion.
+// Only map[string]interface{} and []interface{} are accepted. []interface{} must
+// alternate string keys and arbitrary values, and extraneous ones are ignored.
+func (c Context) Fields(fields interface{}) Context {
+	c.l.context = appendFields(c.l.context, fields, c.l.stack)
 	return c
 }
 
@@ -52,7 +57,7 @@ func (c Context) Array(key string, arr LogArrayMarshaler) Context {
 
 // Object marshals an object that implement the LogObjectMarshaler interface.
 func (c Context) Object(key string, obj LogObjectMarshaler) Context {
-	e := newEvent(levelWriterAdapter{ioutil.Discard}, 0)
+	e := newEvent(LevelWriterAdapter{io.Discard}, 0)
 	e.Object(key, obj)
 	c.l.context = enc.AppendObjectData(c.l.context, e.buf)
 	putEvent(e)
@@ -61,7 +66,7 @@ func (c Context) Object(key string, obj LogObjectMarshaler) Context {
 
 // EmbedObject marshals and Embeds an object that implement the LogObjectMarshaler interface.
 func (c Context) EmbedObject(obj LogObjectMarshaler) Context {
-	e := newEvent(levelWriterAdapter{ioutil.Discard}, 0)
+	e := newEvent(LevelWriterAdapter{io.Discard}, 0)
 	e.EmbedObject(obj)
 	c.l.context = enc.AppendObjectData(c.l.context, e.buf)
 	putEvent(e)
@@ -80,6 +85,17 @@ func (c Context) Strs(key string, vals []string) Context {
 	return c
 }
 
+// Stringer adds the field key with val.String() (or null if val is nil) to the logger context.
+func (c Context) Stringer(key string, val fmt.Stringer) Context {
+	if val != nil {
+		c.l.context = enc.AppendString(enc.AppendKey(c.l.context, key), val.String())
+		return c
+	}
+
+	c.l.context = enc.AppendInterface(enc.AppendKey(c.l.context, key), nil)
+	return c
+}
+
 // Bytes adds the field key with val as a []byte to the logger context.
 func (c Context) Bytes(key string, val []byte) Context {
 	c.l.context = enc.AppendBytes(enc.AppendKey(c.l.context, key), val)
@@ -103,14 +119,17 @@ func (c Context) RawJSON(key string, b []byte) Context {
 
 // AnErr adds the field key with serialized err to the logger context.
 func (c Context) AnErr(key string, err error) Context {
-	marshaled := ErrorMarshalFunc(err)
-	switch m := marshaled.(type) {
+	switch m := ErrorMarshalFunc(err).(type) {
 	case nil:
 		return c
 	case LogObjectMarshaler:
 		return c.Object(key, m)
 	case error:
-		return c.Str(key, m.Error())
+		if m == nil || isNilValue(m) {
+			return c
+		} else {
+			return c.Str(key, m.Error())
+		}
 	case string:
 		return c.Str(key, m)
 	default:
@@ -123,12 +142,15 @@ func (c Context) AnErr(key string, err error) Context {
 func (c Context) Errs(key string, errs []error) Context {
 	arr := Arr()
 	for _, err := range errs {
-		marshaled := ErrorMarshalFunc(err)
-		switch m := marshaled.(type) {
+		switch m := ErrorMarshalFunc(err).(type) {
 		case LogObjectMarshaler:
 			arr = arr.Object(m)
 		case error:
-			arr = arr.Str(m.Error())
+			if m == nil || isNilValue(m) {
+				arr = arr.Interface(nil)
+			} else {
+				arr = arr.Str(m.Error())
+			}
 		case string:
 			arr = arr.Str(m)
 		default:
@@ -141,9 +163,34 @@ func (c Context) Errs(key string, errs []error) Context {
 
 // Err adds the field "error" with serialized err to the logger context.
 func (c Context) Err(err error) Context {
+	if c.l.stack && ErrorStackMarshaler != nil {
+		switch m := ErrorStackMarshaler(err).(type) {
+		case nil:
+		case LogObjectMarshaler:
+			c = c.Object(ErrorStackFieldName, m)
+		case error:
+			if m != nil && !isNilValue(m) {
+				c = c.Str(ErrorStackFieldName, m.Error())
+			}
+		case string:
+			c = c.Str(ErrorStackFieldName, m)
+		default:
+			c = c.Interface(ErrorStackFieldName, m)
+		}
+	}
+
 	return c.AnErr(ErrorFieldName, err)
 }
 
+// Ctx adds the context.Context to the logger context. The context.Context is
+// not rendered in the error message, but is made available for hooks to use.
+// A typical use case is to extract tracing information from the
+// context.Context.
+func (c Context) Ctx(ctx context.Context) Context {
+	c.l.ctx = ctx
+	return c
+}
+
 // Bool adds the field key with val as a bool to the logger context.
 func (c Context) Bool(key string, b bool) Context {
 	c.l.context = enc.AppendBool(enc.AppendKey(c.l.context, key), b)
@@ -278,25 +325,25 @@ func (c Context) Uints64(key string, i []uint64) Context {
 
 // Float32 adds the field key with f as a float32 to the logger context.
 func (c Context) Float32(key string, f float32) Context {
-	c.l.context = enc.AppendFloat32(enc.AppendKey(c.l.context, key), f)
+	c.l.context = enc.AppendFloat32(enc.AppendKey(c.l.context, key), f, FloatingPointPrecision)
 	return c
 }
 
 // Floats32 adds the field key with f as a []float32 to the logger context.
 func (c Context) Floats32(key string, f []float32) Context {
-	c.l.context = enc.AppendFloats32(enc.AppendKey(c.l.context, key), f)
+	c.l.context = enc.AppendFloats32(enc.AppendKey(c.l.context, key), f, FloatingPointPrecision)
 	return c
 }
 
 // Float64 adds the field key with f as a float64 to the logger context.
 func (c Context) Float64(key string, f float64) Context {
-	c.l.context = enc.AppendFloat64(enc.AppendKey(c.l.context, key), f)
+	c.l.context = enc.AppendFloat64(enc.AppendKey(c.l.context, key), f, FloatingPointPrecision)
 	return c
 }
 
 // Floats64 adds the field key with f as a []float64 to the logger context.
 func (c Context) Floats64(key string, f []float64) Context {
-	c.l.context = enc.AppendFloats64(enc.AppendKey(c.l.context, key), f)
+	c.l.context = enc.AppendFloats64(enc.AppendKey(c.l.context, key), f, FloatingPointPrecision)
 	return c
 }
 
@@ -308,8 +355,9 @@ func (ts timestampHook) Run(e *Event, level Level, msg string) {
 
 var th = timestampHook{}
 
-// Timestamp adds the current local time as UNIX timestamp to the logger context with the "time" key.
+// Timestamp adds the current local time to the logger context with the "time" key, formatted using zerolog.TimeFieldFormat.
 // To customize the key name, change zerolog.TimestampFieldName.
+// To customize the time format, change zerolog.TimeFieldFormat.
 //
 // NOTE: It won't dedupe the "time" key if the *Context has one already.
 func (c Context) Timestamp() Context {
@@ -317,13 +365,13 @@ func (c Context) Timestamp() Context {
 	return c
 }
 
-// Time adds the field key with t formated as string using zerolog.TimeFieldFormat.
+// Time adds the field key with t formatted as string using zerolog.TimeFieldFormat.
 func (c Context) Time(key string, t time.Time) Context {
 	c.l.context = enc.AppendTime(enc.AppendKey(c.l.context, key), t, TimeFieldFormat)
 	return c
 }
 
-// Times adds the field key with t formated as string using zerolog.TimeFieldFormat.
+// Times adds the field key with t formatted as string using zerolog.TimeFieldFormat.
 func (c Context) Times(key string, t []time.Time) Context {
 	c.l.context = enc.AppendTimes(enc.AppendKey(c.l.context, key), t, TimeFieldFormat)
 	return c
@@ -331,30 +379,67 @@ func (c Context) Times(key string, t []time.Time) Context {
 
 // Dur adds the fields key with d divided by unit and stored as a float.
 func (c Context) Dur(key string, d time.Duration) Context {
-	c.l.context = enc.AppendDuration(enc.AppendKey(c.l.context, key), d, DurationFieldUnit, DurationFieldInteger)
+	c.l.context = enc.AppendDuration(enc.AppendKey(c.l.context, key), d, DurationFieldUnit, DurationFieldInteger, FloatingPointPrecision)
 	return c
 }
 
 // Durs adds the fields key with d divided by unit and stored as a float.
 func (c Context) Durs(key string, d []time.Duration) Context {
-	c.l.context = enc.AppendDurations(enc.AppendKey(c.l.context, key), d, DurationFieldUnit, DurationFieldInteger)
+	c.l.context = enc.AppendDurations(enc.AppendKey(c.l.context, key), d, DurationFieldUnit, DurationFieldInteger, FloatingPointPrecision)
 	return c
 }
 
 // Interface adds the field key with obj marshaled using reflection.
 func (c Context) Interface(key string, i interface{}) Context {
+	if obj, ok := i.(LogObjectMarshaler); ok {
+		return c.Object(key, obj)
+	}
 	c.l.context = enc.AppendInterface(enc.AppendKey(c.l.context, key), i)
 	return c
 }
 
-type callerHook struct{}
-
-func (ch callerHook) Run(e *Event, level Level, msg string) {
-	// Three extra frames to skip (added by hook infra).
-	e.caller(CallerSkipFrameCount + 3)
+// Type adds the field key with val's type using reflection.
+func (c Context) Type(key string, val interface{}) Context {
+	c.l.context = enc.AppendType(enc.AppendKey(c.l.context, key), val)
+	return c
 }
 
-var ch = callerHook{}
+// Any is a wrapper around Context.Interface.
+func (c Context) Any(key string, i interface{}) Context {
+	return c.Interface(key, i)
+}
+
+// Reset removes all the context fields.
+func (c Context) Reset() Context {
+	c.l.context = enc.AppendBeginMarker(make([]byte, 0, 500))
+	return c
+}
+
+type callerHook struct {
+	callerSkipFrameCount int
+}
+
+func newCallerHook(skipFrameCount int) callerHook {
+	return callerHook{callerSkipFrameCount: skipFrameCount}
+}
+
+func (ch callerHook) Run(e *Event, level Level, msg string) {
+	switch ch.callerSkipFrameCount {
+	case useGlobalSkipFrameCount:
+		// Extra frames to skip (added by hook infra).
+		e.caller(CallerSkipFrameCount + contextCallerSkipFrameCount)
+	default:
+		// Extra frames to skip (added by hook infra).
+		e.caller(ch.callerSkipFrameCount + contextCallerSkipFrameCount)
+	}
+}
+
+// useGlobalSkipFrameCount acts as a flag to informat callerHook.Run
+// to use the global CallerSkipFrameCount.
+const useGlobalSkipFrameCount = math.MinInt32
+
+// ch is the default caller hook using the global CallerSkipFrameCount.
+var ch = newCallerHook(useGlobalSkipFrameCount)
 
 // Caller adds the file:line of the caller with the zerolog.CallerFieldName key.
 func (c Context) Caller() Context {
@@ -362,6 +447,20 @@ func (c Context) Caller() Context {
 	return c
 }
 
+// CallerWithSkipFrameCount adds the file:line of the caller with the zerolog.CallerFieldName key.
+// The specified skipFrameCount int will override the global CallerSkipFrameCount for this context's respective logger.
+// If set to -1 the global CallerSkipFrameCount will be used.
+func (c Context) CallerWithSkipFrameCount(skipFrameCount int) Context {
+	c.l = c.l.Hook(newCallerHook(skipFrameCount))
+	return c
+}
+
+// Stack enables stack trace printing for the error passed to Err().
+func (c Context) Stack() Context {
+	c.l.stack = true
+	return c
+}
+
 // IPAddr adds IPv4 or IPv6 Address to the context
 func (c Context) IPAddr(key string, ip net.IP) Context {
 	c.l.context = enc.AppendIPAddr(enc.AppendKey(c.l.context, key), ip)

ctx.go

@@ -7,16 +7,22 @@ import (
 var disabledLogger *Logger
 
 func init() {
+	SetGlobalLevel(TraceLevel)
 	l := Nop()
 	disabledLogger = &l
 }
 
 type ctxKey struct{}
 
-// WithContext returns a copy of ctx with l associated. If an instance of Logger
-// is already in the context, the context is not updated.
+// WithContext returns a copy of ctx with the receiver attached. The Logger
+// attached to the provided Context (if any) will not be effected.  If the
+// receiver's log level is Disabled it will only be attached to the returned
+// Context if the provided Context has a previously attached Logger. If the
+// provided Context has no attached Logger, a Disabled Logger will not be
+// attached.
 //
-// For instance, to add a field to an existing logger in the context, use this
+// Note: to modify the existing Logger attached to a Context (instead of
+// replacing it in a new Context), use UpdateContext with the following
 // notation:
 //
 //     ctx := r.Context()
@@ -24,24 +30,23 @@ type ctxKey struct{}
 //     l.UpdateContext(func(c Context) Context {
 //         return c.Str("bar", "baz")
 //     })
-func (l *Logger) WithContext(ctx context.Context) context.Context {
-	if lp, ok := ctx.Value(ctxKey{}).(*Logger); ok {
-		if lp == l {
-			// Do not store same logger.
-			return ctx
-		}
-	} else if l.level == Disabled {
+//
+func (l Logger) WithContext(ctx context.Context) context.Context {
+	if _, ok := ctx.Value(ctxKey{}).(*Logger); !ok && l.level == Disabled {
 		// Do not store disabled logger.
 		return ctx
 	}
-	return context.WithValue(ctx, ctxKey{}, l)
+	return context.WithValue(ctx, ctxKey{}, &l)
 }
 
 // Ctx returns the Logger associated with the ctx. If no logger
-// is associated, a disabled logger is returned.
+// is associated, DefaultContextLogger is returned, unless DefaultContextLogger
+// is nil, in which case a disabled logger is returned.
 func Ctx(ctx context.Context) *Logger {
 	if l, ok := ctx.Value(ctxKey{}).(*Logger); ok {
 		return l
+	} else if l = DefaultContextLogger; l != nil {
+		return l
 	}
 	return disabledLogger
 }

ctx_test.go

@@ -1,14 +1,17 @@
 package zerolog
 
 import (
+	"bytes"
 	"context"
-	"io/ioutil"
+	"io"
 	"reflect"
 	"testing"
+
+	"github.com/rs/zerolog/internal/cbor"
 )
 
 func TestCtx(t *testing.T) {
-	log := New(ioutil.Discard)
+	log := New(io.Discard)
 	ctx := log.WithContext(context.Background())
 	log2 := Ctx(ctx)
 	if !reflect.DeepEqual(log, *log2) {
@@ -27,18 +30,25 @@ func TestCtx(t *testing.T) {
 	if log2 != disabledLogger {
 		t.Error("Ctx did not return the expected logger")
 	}
+
+	DefaultContextLogger = &log
+	t.Cleanup(func() { DefaultContextLogger = nil })
+	log2 = Ctx(context.Background())
+	if log2 != &log {
+		t.Error("Ctx did not return the expected logger")
+	}
 }
 
 func TestCtxDisabled(t *testing.T) {
-	dl := New(ioutil.Discard).Level(Disabled)
+	dl := New(io.Discard).Level(Disabled)
 	ctx := dl.WithContext(context.Background())
 	if ctx != context.Background() {
 		t.Error("WithContext stored a disabled logger")
 	}
 
-	l := New(ioutil.Discard).With().Str("foo", "bar").Logger()
+	l := New(io.Discard).With().Str("foo", "bar").Logger()
 	ctx = l.WithContext(ctx)
-	if Ctx(ctx) != &l {
+	if !reflect.DeepEqual(Ctx(ctx), &l) {
 		t.Error("WithContext did not store logger")
 	}
 
@@ -46,18 +56,46 @@ func TestCtxDisabled(t *testing.T) {
 		return c.Str("bar", "baz")
 	})
 	ctx = l.WithContext(ctx)
-	if Ctx(ctx) != &l {
+	if !reflect.DeepEqual(Ctx(ctx), &l) {
 		t.Error("WithContext did not store updated logger")
 	}
 
 	l = l.Level(DebugLevel)
 	ctx = l.WithContext(ctx)
-	if Ctx(ctx) != &l {
+	if !reflect.DeepEqual(Ctx(ctx), &l) {
 		t.Error("WithContext did not store copied logger")
 	}
 
 	ctx = dl.WithContext(ctx)
-	if Ctx(ctx) != &dl {
-		t.Error("WithContext did not overide logger with a disabled logger")
+	if !reflect.DeepEqual(Ctx(ctx), &dl) {
+		t.Error("WithContext did not override logger with a disabled logger")
+	}
+}
+
+type logObjectMarshalerImpl struct {
+	name string
+	age  int
+}
+
+func (t logObjectMarshalerImpl) MarshalZerologObject(e *Event) {
+	e.Str("name", "custom_value").Int("age", t.age)
+}
+
+func Test_InterfaceLogObjectMarshaler(t *testing.T) {
+	var buf bytes.Buffer
+	log := New(&buf)
+	ctx := log.WithContext(context.Background())
+
+	log2 := Ctx(ctx)
+
+	withLog := log2.With().Interface("obj", &logObjectMarshalerImpl{
+		name: "foo",
+		age:  29,
+	}).Logger()
+
+	withLog.Info().Msg("test")
+
+	if got, want := cbor.DecodeIfBinaryToString(buf.Bytes()), `{"level":"info","obj":{"name":"custom_value","age":29},"message":"test"}`+"\n"; got != want {
+		t.Errorf("got %q, want %q", got, want)
 	}
 }

diode/diode.go

@@ -48,7 +48,7 @@ type Writer struct {
 // used.
 //
 // See code.cloudfoundry.org/go-diodes for more info on diode.
-func NewWriter(w io.Writer, size int, poolInterval time.Duration, f Alerter) Writer {
+func NewWriter(w io.Writer, size int, pollInterval time.Duration, f Alerter) Writer {
 	ctx, cancel := context.WithCancel(context.Background())
 	dw := Writer{
 		w:    w,
@@ -59,9 +59,9 @@ func NewWriter(w io.Writer, size int, poolInterval time.Duration, f Alerter) Wri
 		f = func(int) {}
 	}
 	d := diodes.NewManyToOne(size, diodes.AlertFunc(f))
-	if poolInterval > 0 {
+	if pollInterval > 0 {
 		dw.d = diodes.NewPoller(d,
-			diodes.WithPollingInterval(poolInterval),
+			diodes.WithPollingInterval(pollInterval),
 			diodes.WithPollingContext(ctx))
 	} else {
 		dw.d = diodes.NewWaiter(d,

diode/diode_test.go

@@ -3,9 +3,10 @@ package diode_test
 import (
 	"bytes"
 	"fmt"
-	"io/ioutil"
+	"io"
 	"log"
 	"os"
+	"os/exec"
 	"testing"
 	"time"
 
@@ -30,8 +31,53 @@ func TestNewWriter(t *testing.T) {
 	}
 }
 
+func TestClose(t *testing.T) {
+	buf := bytes.Buffer{}
+	w := diode.NewWriter(&buf, 1000, 0, func(missed int) {})
+	log := zerolog.New(w)
+	log.Print("test")
+	w.Close()
+}
+
+func TestFatal(t *testing.T) {
+	if os.Getenv("TEST_FATAL") == "1" {
+		w := diode.NewWriter(os.Stderr, 1000, 0, func(missed int) {
+			fmt.Printf("Dropped %d messages\n", missed)
+		})
+		defer w.Close()
+		log := zerolog.New(w)
+		log.Fatal().Msg("test")
+		return
+	}
+
+	cmd := exec.Command(os.Args[0], "-test.run=TestFatal")
+	cmd.Env = append(os.Environ(), "TEST_FATAL=1")
+	stderr, err := cmd.StderrPipe()
+	if err != nil {
+		t.Fatal(err)
+	}
+	err = cmd.Start()
+	if err != nil {
+		t.Fatal(err)
+	}
+	slurp, err := io.ReadAll(stderr)
+	if err != nil {
+		t.Fatal(err)
+	}
+	err = cmd.Wait()
+	if err == nil {
+		t.Error("Expected log.Fatal to exit with non-zero status")
+	}
+
+	want := "{\"level\":\"fatal\",\"message\":\"test\"}\n"
+	got := cbor.DecodeIfBinaryToString(slurp)
+	if got != want {
+		t.Errorf("Diode Fatal Test failed. got:%s, want:%s!", got, want)
+	}
+}
+
 func Benchmark(b *testing.B) {
-	log.SetOutput(ioutil.Discard)
+	log.SetOutput(io.Discard)
 	defer log.SetOutput(os.Stderr)
 	benchs := map[string]time.Duration{
 		"Waiter": 0,
@@ -39,7 +85,7 @@ func Benchmark(b *testing.B) {
 	}
 	for name, interval := range benchs {
 		b.Run(name, func(b *testing.B) {
-			w := diode.NewWriter(ioutil.Discard, 100000, interval, nil)
+			w := diode.NewWriter(io.Discard, 100000, interval, nil)
 			log := zerolog.New(w)
 			defer w.Close()
 

diode/internal/diodes/many_to_one.go

@@ -9,14 +9,14 @@ import (
 // ManyToOne diode is optimal for many writers (go-routines B-n) and a single
 // reader (go-routine A). It is not thread safe for multiple readers.
 type ManyToOne struct {
-	buffer     []unsafe.Pointer
 	writeIndex uint64
 	readIndex  uint64
+	buffer     []unsafe.Pointer
 	alerter    Alerter
 }
 
 // NewManyToOne creates a new diode (ring buffer). The ManyToOne diode
-// is optimzed for many writers (on go-routines B-n) and a single reader
+// is optimized for many writers (on go-routines B-n) and a single reader
 // (on go-routine A). The alerter is invoked on the read's go-routine. It is
 // called when it notices that the writer go-routine has passed it and wrote
 // over data. A nil can be used to ignore alerts.
@@ -66,7 +66,7 @@ func (d *ManyToOne) Set(data GenericDataType) {
 }
 
 // TryNext will attempt to read from the next slot of the ring buffer.
-// If there is not data available, it will return (nil, false).
+// If there is no data available, it will return (nil, false).
 func (d *ManyToOne) TryNext() (data GenericDataType, ok bool) {
 	// Read a value from the ring buffer based on the readIndex.
 	idx := d.readIndex % uint64(len(d.buffer))
@@ -80,7 +80,7 @@ func (d *ManyToOne) TryNext() (data GenericDataType, ok bool) {
 	}
 
 	// When the seq value is less than the current read index that means a
-	// value was read from idx that was previously written but has since has
+	// value was read from idx that was previously written but since has
 	// been dropped. This value must be ignored and the read head must not
 	// increment.
 	//

diode/internal/diodes/one_to_one.go

@@ -31,9 +31,9 @@ type bucket struct {
 // OneToOne diode is meant to be used by a single reader and a single writer.
 // It is not thread safe if used otherwise.
 type OneToOne struct {
-	buffer     []unsafe.Pointer
 	writeIndex uint64
 	readIndex  uint64
+	buffer     []unsafe.Pointer
 	alerter    Alerter
 }
 
@@ -80,7 +80,7 @@ func (d *OneToOne) TryNext() (data GenericDataType, ok bool) {
 	}
 
 	// When the seq value is less than the current read index that means a
-	// value was read from idx that was previously written but has since has
+	// value was read from idx that was previously written but since has
 	// been dropped. This value must be ignored and the read head must not
 	// increment.
 	//

diode/internal/diodes/poller.go

@@ -24,18 +24,18 @@ type PollerConfigOption func(*Poller)
 // WithPollingInterval sets the interval at which the diode is queried
 // for new data. The default is 10ms.
 func WithPollingInterval(interval time.Duration) PollerConfigOption {
-	return PollerConfigOption(func(c *Poller) {
+	return func(c *Poller) {
 		c.interval = interval
-	})
+	}
 }
 
 // WithPollingContext sets the context to cancel any retrieval (Next()). It
 // will not change any results for adding data (Set()). Default is
 // context.Background().
 func WithPollingContext(ctx context.Context) PollerConfigOption {
-	return PollerConfigOption(func(c *Poller) {
+	return func(c *Poller) {
 		c.ctx = ctx
-	})
+	}
 }
 
 // NewPoller returns a new Poller that wraps the given diode.

diode/internal/diodes/waiter.go

@@ -21,9 +21,9 @@ type WaiterConfigOption func(*Waiter)
 // will not change any results for adding data (Set()). Default is
 // context.Background().
 func WithWaiterContext(ctx context.Context) WaiterConfigOption {
-	return WaiterConfigOption(func(c *Waiter) {
+	return func(c *Waiter) {
 		c.ctx = ctx
-	})
+	}
 }
 
 // NewWaiter returns a new Waiter that wraps the given diode.
@@ -39,7 +39,12 @@ func NewWaiter(d Diode, opts ...WaiterConfigOption) *Waiter {
 
 	go func() {
 		<-w.ctx.Done()
+
+		// Mutex is strictly necessary here to avoid a race in Next() (between
+		// w.isDone() and w.c.Wait()) and w.c.Broadcast() here.
+		w.mu.Lock()
 		w.c.Broadcast()
+		w.mu.Unlock()
 	}()
 
 	return w

encoder.go

@@ -13,13 +13,13 @@ type encoder interface {
 	AppendBool(dst []byte, val bool) []byte
 	AppendBools(dst []byte, vals []bool) []byte
 	AppendBytes(dst, s []byte) []byte
-	AppendDuration(dst []byte, d time.Duration, unit time.Duration, useInt bool) []byte
-	AppendDurations(dst []byte, vals []time.Duration, unit time.Duration, useInt bool) []byte
+	AppendDuration(dst []byte, d time.Duration, unit time.Duration, useInt bool, precision int) []byte
+	AppendDurations(dst []byte, vals []time.Duration, unit time.Duration, useInt bool, precision int) []byte
 	AppendEndMarker(dst []byte) []byte
-	AppendFloat32(dst []byte, val float32) []byte
-	AppendFloat64(dst []byte, val float64) []byte
-	AppendFloats32(dst []byte, vals []float32) []byte
-	AppendFloats64(dst []byte, vals []float64) []byte
+	AppendFloat32(dst []byte, val float32, precision int) []byte
+	AppendFloat64(dst []byte, val float64, precision int) []byte
+	AppendFloats32(dst []byte, vals []float32, precision int) []byte
+	AppendFloats64(dst []byte, vals []float64, precision int) []byte
 	AppendHex(dst, s []byte) []byte
 	AppendIPAddr(dst []byte, ip net.IP) []byte
 	AppendIPPrefix(dst []byte, pfx net.IPNet) []byte

encoder_cbor.go

@@ -14,9 +14,19 @@ var (
 	enc = cbor.Encoder{}
 )
 
+func init() {
+	// using closure to reflect the changes at runtime.
+	cbor.JSONMarshalFunc = func(v interface{}) ([]byte, error) {
+		return InterfaceMarshalFunc(v)
+	}
+}
+
 func appendJSON(dst []byte, j []byte) []byte {
 	return cbor.AppendEmbeddedJSON(dst, j)
 }
+func appendCBOR(dst []byte, c []byte) []byte {
+	return cbor.AppendEmbeddedCBOR(dst, c)
+}
 
 // decodeIfBinaryToString - converts a binary formatted log msg to a
 // JSON formatted String Log message.

encoder_json.go

@@ -6,6 +6,7 @@ package zerolog
 // JSON encoded byte stream.
 
 import (
+	"encoding/base64"
 	"github.com/rs/zerolog/internal/json"
 )
 
@@ -15,9 +16,27 @@ var (
 	enc = json.Encoder{}
 )
 
+func init() {
+	// using closure to reflect the changes at runtime.
+	json.JSONMarshalFunc = func(v interface{}) ([]byte, error) {
+		return InterfaceMarshalFunc(v)
+	}
+}
+
 func appendJSON(dst []byte, j []byte) []byte {
 	return append(dst, j...)
 }
+func appendCBOR(dst []byte, cbor []byte) []byte {
+	dst = append(dst, []byte("\"data:application/cbor;base64,")...)
+	l := len(dst)
+	enc := base64.StdEncoding
+	n := enc.EncodedLen(len(cbor))
+	for i := 0; i < n; i++ {
+		dst = append(dst, '.')
+	}
+	enc.Encode(dst[l:], cbor)
+	return append(dst, '"')
+}
 
 func decodeIfBinaryToString(in []byte) string {
 	return string(in)

event.go

@@ -1,11 +1,11 @@
 package zerolog
 
 import (
+	"context"
 	"fmt"
 	"net"
 	"os"
 	"runtime"
-	"strconv"
 	"sync"
 	"time"
 )
@@ -18,19 +18,17 @@ var eventPool = &sync.Pool{
 	},
 }
 
-// ErrorMarshalFunc allows customization of global error marshaling
-var ErrorMarshalFunc = func(err error) interface{} {
-	return err
-}
-
 // Event represents a log event. It is instanced by one of the level method of
 // Logger and finalized by the Msg or Msgf method.
 type Event struct {
-	buf   []byte
-	w     LevelWriter
-	level Level
-	done  func(msg string)
-	ch    []Hook // hooks from context
+	buf       []byte
+	w         LevelWriter
+	level     Level
+	done      func(msg string)
+	stack     bool            // enable error stack trace
+	ch        []Hook          // hooks from context
+	skipFrame int             // The number of additional frames to skip when printing the caller.
+	ctx       context.Context // Optional Go context for event
 }
 
 func putEvent(e *Event) {
@@ -66,6 +64,8 @@ func newEvent(w LevelWriter, level Level) *Event {
 	e.buf = enc.AppendBeginMarker(e.buf)
 	e.w = w
 	e.level = level
+	e.stack = false
+	e.skipFrame = 0
 	return e
 }
 
@@ -110,10 +110,20 @@ func (e *Event) Msg(msg string) {
 	e.msg(msg)
 }
 
-// Msgf sends the event with formated msg added as the message field if not empty.
+// Send is equivalent to calling Msg("").
 //
-// NOTICE: once this methid is called, the *Event should be disposed.
-// Calling Msg twice can have unexpected result.
+// NOTICE: once this method is called, the *Event should be disposed.
+func (e *Event) Send() {
+	if e == nil {
+		return
+	}
+	e.msg("")
+}
+
+// Msgf sends the event with formatted msg added as the message field if not empty.
+//
+// NOTICE: once this method is called, the *Event should be disposed.
+// Calling Msgf twice can have unexpected result.
 func (e *Event) Msgf(format string, v ...interface{}) {
 	if e == nil {
 		return
@@ -121,14 +131,16 @@ func (e *Event) Msgf(format string, v ...interface{}) {
 	e.msg(fmt.Sprintf(format, v...))
 }
 
+func (e *Event) MsgFunc(createMsg func() string) {
+	if e == nil {
+		return
+	}
+	e.msg(createMsg())
+}
+
 func (e *Event) msg(msg string) {
-	if len(e.ch) > 0 {
-		e.ch[0].Run(e, e.level, msg)
-		if len(e.ch) > 1 {
-			for _, hook := range e.ch[1:] {
-				hook.Run(e, e.level, msg)
-			}
-		}
+	for _, hook := range e.ch {
+		hook.Run(e, e.level, msg)
 	}
 	if msg != "" {
 		e.buf = enc.AppendString(enc.AppendKey(e.buf, MessageFieldName), msg)
@@ -145,12 +157,14 @@ func (e *Event) msg(msg string) {
 	}
 }
 
-// Fields is a helper function to use a map to set fields using type assertion.
-func (e *Event) Fields(fields map[string]interface{}) *Event {
+// Fields is a helper function to use a map or slice to set fields using type assertion.
+// Only map[string]interface{} and []interface{} are accepted. []interface{} must
+// alternate string keys and arbitrary values, and extraneous ones are ignored.
+func (e *Event) Fields(fields interface{}) *Event {
 	if e == nil {
 		return e
 	}
-	e.buf = appendFields(e.buf, fields)
+	e.buf = appendFields(e.buf, fields, e.stack)
 	return e
 }
 
@@ -204,15 +218,32 @@ func (e *Event) Object(key string, obj LogObjectMarshaler) *Event {
 		return e
 	}
 	e.buf = enc.AppendKey(e.buf, key)
+	if obj == nil {
+		e.buf = enc.AppendNil(e.buf)
+
+		return e
+	}
+
 	e.appendObject(obj)
 	return e
 }
 
-// Object marshals an object that implement the LogObjectMarshaler interface.
+// Func allows an anonymous func to run only if the event is enabled.
+func (e *Event) Func(f func(e *Event)) *Event {
+	if e != nil && e.Enabled() {
+		f(e)
+	}
+	return e
+}
+
+// EmbedObject marshals an object that implement the LogObjectMarshaler interface.
 func (e *Event) EmbedObject(obj LogObjectMarshaler) *Event {
 	if e == nil {
 		return e
 	}
+	if obj == nil {
+		return e
+	}
 	obj.MarshalZerologObject(e)
 	return e
 }
@@ -235,6 +266,27 @@ func (e *Event) Strs(key string, vals []string) *Event {
 	return e
 }
 
+// Stringer adds the field key with val.String() (or null if val is nil)
+// to the *Event context.
+func (e *Event) Stringer(key string, val fmt.Stringer) *Event {
+	if e == nil {
+		return e
+	}
+	e.buf = enc.AppendStringer(enc.AppendKey(e.buf, key), val)
+	return e
+}
+
+// Stringers adds the field key with vals where each individual val
+// is used as val.String() (or null if val is empty) to the *Event
+// context.
+func (e *Event) Stringers(key string, vals []fmt.Stringer) *Event {
+	if e == nil {
+		return e
+	}
+	e.buf = enc.AppendStringers(enc.AppendKey(e.buf, key), vals)
+	return e
+}
+
 // Bytes adds the field key with val as a string to the *Event context.
 //
 // Runes outside of normal ASCII ranges will be hex-encoded in the resulting
@@ -268,17 +320,35 @@ func (e *Event) RawJSON(key string, b []byte) *Event {
 	return e
 }
 
+// RawCBOR adds already encoded CBOR to the log line under key.
+//
+// No sanity check is performed on b
+// Note: The full featureset of CBOR is supported as data will not be mapped to json but stored as data-url
+func (e *Event) RawCBOR(key string, b []byte) *Event {
+	if e == nil {
+		return e
+	}
+	e.buf = appendCBOR(enc.AppendKey(e.buf, key), b)
+	return e
+}
+
 // AnErr adds the field key with serialized err to the *Event context.
 // If err is nil, no field is added.
 func (e *Event) AnErr(key string, err error) *Event {
-	marshaled := ErrorMarshalFunc(err)
-	switch m := marshaled.(type) {
+	if e == nil {
+		return e
+	}
+	switch m := ErrorMarshalFunc(err).(type) {
 	case nil:
 		return e
 	case LogObjectMarshaler:
 		return e.Object(key, m)
 	case error:
-		return e.Str(key, m.Error())
+		if m == nil || isNilValue(m) {
+			return e
+		} else {
+			return e.Str(key, m.Error())
+		}
 	case string:
 		return e.Str(key, m)
 	default:
@@ -292,11 +362,9 @@ func (e *Event) Errs(key string, errs []error) *Event {
 	if e == nil {
 		return e
 	}
-
 	arr := Arr()
 	for _, err := range errs {
-		marshaled := ErrorMarshalFunc(err)
-		switch m := marshaled.(type) {
+		switch m := ErrorMarshalFunc(err).(type) {
 		case LogObjectMarshaler:
 			arr = arr.Object(m)
 		case error:
@@ -313,11 +381,66 @@ func (e *Event) Errs(key string, errs []error) *Event {
 
 // Err adds the field "error" with serialized err to the *Event context.
 // If err is nil, no field is added.
+//
 // To customize the key name, change zerolog.ErrorFieldName.
+//
+// If Stack() has been called before and zerolog.ErrorStackMarshaler is defined,
+// the err is passed to ErrorStackMarshaler and the result is appended to the
+// zerolog.ErrorStackFieldName.
 func (e *Event) Err(err error) *Event {
+	if e == nil {
+		return e
+	}
+	if e.stack && ErrorStackMarshaler != nil {
+		switch m := ErrorStackMarshaler(err).(type) {
+		case nil:
+		case LogObjectMarshaler:
+			e.Object(ErrorStackFieldName, m)
+		case error:
+			if m != nil && !isNilValue(m) {
+				e.Str(ErrorStackFieldName, m.Error())
+			}
+		case string:
+			e.Str(ErrorStackFieldName, m)
+		default:
+			e.Interface(ErrorStackFieldName, m)
+		}
+	}
 	return e.AnErr(ErrorFieldName, err)
 }
 
+// Stack enables stack trace printing for the error passed to Err().
+//
+// ErrorStackMarshaler must be set for this method to do something.
+func (e *Event) Stack() *Event {
+	if e != nil {
+		e.stack = true
+	}
+	return e
+}
+
+// Ctx adds the Go Context to the *Event context.  The context is not rendered
+// in the output message, but is available to hooks and to Func() calls via the
+// GetCtx() accessor. A typical use case is to extract tracing information from
+// the Go Ctx.
+func (e *Event) Ctx(ctx context.Context) *Event {
+	if e != nil {
+		e.ctx = ctx
+	}
+	return e
+}
+
+// GetCtx retrieves the Go context.Context which is optionally stored in the
+// Event.  This allows Hooks and functions passed to Func() to retrieve values
+// which are stored in the context.Context.  This can be useful in tracing,
+// where span information is commonly propagated in the context.Context.
+func (e *Event) GetCtx() context.Context {
+	if e == nil || e.ctx == nil {
+		return context.Background()
+	}
+	return e.ctx
+}
+
 // Bool adds the field key with val as a bool to the *Event context.
 func (e *Event) Bool(key string, b bool) *Event {
 	if e == nil {
@@ -521,7 +644,7 @@ func (e *Event) Float32(key string, f float32) *Event {
 	if e == nil {
 		return e
 	}
-	e.buf = enc.AppendFloat32(enc.AppendKey(e.buf, key), f)
+	e.buf = enc.AppendFloat32(enc.AppendKey(e.buf, key), f, FloatingPointPrecision)
 	return e
 }
 
@@ -530,7 +653,7 @@ func (e *Event) Floats32(key string, f []float32) *Event {
 	if e == nil {
 		return e
 	}
-	e.buf = enc.AppendFloats32(enc.AppendKey(e.buf, key), f)
+	e.buf = enc.AppendFloats32(enc.AppendKey(e.buf, key), f, FloatingPointPrecision)
 	return e
 }
 
@@ -539,7 +662,7 @@ func (e *Event) Float64(key string, f float64) *Event {
 	if e == nil {
 		return e
 	}
-	e.buf = enc.AppendFloat64(enc.AppendKey(e.buf, key), f)
+	e.buf = enc.AppendFloat64(enc.AppendKey(e.buf, key), f, FloatingPointPrecision)
 	return e
 }
 
@@ -548,7 +671,7 @@ func (e *Event) Floats64(key string, f []float64) *Event {
 	if e == nil {
 		return e
 	}
-	e.buf = enc.AppendFloats64(enc.AppendKey(e.buf, key), f)
+	e.buf = enc.AppendFloats64(enc.AppendKey(e.buf, key), f, FloatingPointPrecision)
 	return e
 }
 
@@ -565,7 +688,7 @@ func (e *Event) Timestamp() *Event {
 	return e
 }
 
-// Time adds the field key with t formated as string using zerolog.TimeFieldFormat.
+// Time adds the field key with t formatted as string using zerolog.TimeFieldFormat.
 func (e *Event) Time(key string, t time.Time) *Event {
 	if e == nil {
 		return e
@@ -574,7 +697,7 @@ func (e *Event) Time(key string, t time.Time) *Event {
 	return e
 }
 
-// Times adds the field key with t formated as string using zerolog.TimeFieldFormat.
+// Times adds the field key with t formatted as string using zerolog.TimeFieldFormat.
 func (e *Event) Times(key string, t []time.Time) *Event {
 	if e == nil {
 		return e
@@ -590,7 +713,7 @@ func (e *Event) Dur(key string, d time.Duration) *Event {
 	if e == nil {
 		return e
 	}
-	e.buf = enc.AppendDuration(enc.AppendKey(e.buf, key), d, DurationFieldUnit, DurationFieldInteger)
+	e.buf = enc.AppendDuration(enc.AppendKey(e.buf, key), d, DurationFieldUnit, DurationFieldInteger, FloatingPointPrecision)
 	return e
 }
 
@@ -601,7 +724,7 @@ func (e *Event) Durs(key string, d []time.Duration) *Event {
 	if e == nil {
 		return e
 	}
-	e.buf = enc.AppendDurations(enc.AppendKey(e.buf, key), d, DurationFieldUnit, DurationFieldInteger)
+	e.buf = enc.AppendDurations(enc.AppendKey(e.buf, key), d, DurationFieldUnit, DurationFieldInteger, FloatingPointPrecision)
 	return e
 }
 
@@ -616,10 +739,15 @@ func (e *Event) TimeDiff(key string, t time.Time, start time.Time) *Event {
 	if t.After(start) {
 		d = t.Sub(start)
 	}
-	e.buf = enc.AppendDuration(enc.AppendKey(e.buf, key), d, DurationFieldUnit, DurationFieldInteger)
+	e.buf = enc.AppendDuration(enc.AppendKey(e.buf, key), d, DurationFieldUnit, DurationFieldInteger, FloatingPointPrecision)
 	return e
 }
 
+// Any is a wrapper around Event.Interface.
+func (e *Event) Any(key string, i interface{}) *Event {
+	return e.Interface(key, i)
+}
+
 // Interface adds the field key with i marshaled using reflection.
 func (e *Event) Interface(key string, i interface{}) *Event {
 	if e == nil {
@@ -632,20 +760,45 @@ func (e *Event) Interface(key string, i interface{}) *Event {
 	return e
 }
 
+// Type adds the field key with val's type using reflection.
+func (e *Event) Type(key string, val interface{}) *Event {
+	if e == nil {
+		return e
+	}
+	e.buf = enc.AppendType(enc.AppendKey(e.buf, key), val)
+	return e
+}
+
+// CallerSkipFrame instructs any future Caller calls to skip the specified number of frames.
+// This includes those added via hooks from the context.
+func (e *Event) CallerSkipFrame(skip int) *Event {
+	if e == nil {
+		return e
+	}
+	e.skipFrame += skip
+	return e
+}
+
 // Caller adds the file:line of the caller with the zerolog.CallerFieldName key.
-func (e *Event) Caller() *Event {
-	return e.caller(CallerSkipFrameCount)
+// The argument skip is the number of stack frames to ascend
+// Skip If not passed, use the global variable CallerSkipFrameCount
+func (e *Event) Caller(skip ...int) *Event {
+	sk := CallerSkipFrameCount
+	if len(skip) > 0 {
+		sk = skip[0] + CallerSkipFrameCount
+	}
+	return e.caller(sk)
 }
 
 func (e *Event) caller(skip int) *Event {
 	if e == nil {
 		return e
 	}
-	_, file, line, ok := runtime.Caller(skip)
+	pc, file, line, ok := runtime.Caller(skip + e.skipFrame)
 	if !ok {
 		return e
 	}
-	e.buf = enc.AppendString(enc.AppendKey(e.buf, CallerFieldName), file+":"+strconv.Itoa(line))
+	e.buf = enc.AppendString(enc.AppendKey(e.buf, CallerFieldName), CallerMarshalFunc(pc, file, line))
 	return e
 }
 

event_test.go

@@ -0,0 +1,65 @@
+// +build !binary_log
+
+package zerolog
+
+import (
+	"bytes"
+	"errors"
+	"strings"
+	"testing"
+)
+
+type nilError struct{}
+
+func (nilError) Error() string {
+	return ""
+}
+
+func TestEvent_AnErr(t *testing.T) {
+	tests := []struct {
+		name string
+		err  error
+		want string
+	}{
+		{"nil", nil, `{}`},
+		{"error", errors.New("test"), `{"err":"test"}`},
+		{"nil interface", func() *nilError { return nil }(), `{}`},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			var buf bytes.Buffer
+			e := newEvent(LevelWriterAdapter{&buf}, DebugLevel)
+			e.AnErr("err", tt.err)
+			_ = e.write()
+			if got, want := strings.TrimSpace(buf.String()), tt.want; got != want {
+				t.Errorf("Event.AnErr() = %v, want %v", got, want)
+			}
+		})
+	}
+}
+
+func TestEvent_ObjectWithNil(t *testing.T) {
+	var buf bytes.Buffer
+	e := newEvent(LevelWriterAdapter{&buf}, DebugLevel)
+	_ = e.Object("obj", nil)
+	_ = e.write()
+
+	want := `{"obj":null}`
+	got := strings.TrimSpace(buf.String())
+	if got != want {
+		t.Errorf("Event.Object() = %q, want %q", got, want)
+	}
+}
+
+func TestEvent_EmbedObjectWithNil(t *testing.T) {
+	var buf bytes.Buffer
+	e := newEvent(LevelWriterAdapter{&buf}, DebugLevel)
+	_ = e.EmbedObject(nil)
+	_ = e.write()
+
+	want := "{}"
+	got := strings.TrimSpace(buf.String())
+	if got != want {
+		t.Errorf("Event.EmbedObject() = %q, want %q", got, want)
+	}
+}

example.jsonl

@@ -0,0 +1,7 @@
+{"time":"5:41PM","level":"info","message":"Starting listener","listen":":8080","pid":37556}
+{"time":"5:41PM","level":"debug","message":"Access","database":"myapp","host":"localhost:4962","pid":37556}
+{"time":"5:41PM","level":"info","message":"Access","method":"GET","path":"/users","pid":37556,"resp_time":23}
+{"time":"5:41PM","level":"info","message":"Access","method":"POST","path":"/posts","pid":37556,"resp_time":532}
+{"time":"5:41PM","level":"warn","message":"Slow request","method":"POST","path":"/posts","pid":37556,"resp_time":532}
+{"time":"5:41PM","level":"info","message":"Access","method":"GET","path":"/users","pid":37556,"resp_time":10}
+{"time":"5:41PM","level":"error","message":"Database connection lost","database":"myapp","pid":37556,"error":"connection reset by peer"}

fields.go

@@ -1,20 +1,47 @@
 package zerolog
 
 import (
+	"encoding/json"
 	"net"
 	"sort"
 	"time"
+	"unsafe"
 )
 
-func appendFields(dst []byte, fields map[string]interface{}) []byte {
-	keys := make([]string, 0, len(fields))
-	for key := range fields {
-		keys = append(keys, key)
+func isNilValue(i interface{}) bool {
+	return (*[2]uintptr)(unsafe.Pointer(&i))[1] == 0
+}
+
+func appendFields(dst []byte, fields interface{}, stack bool) []byte {
+	switch fields := fields.(type) {
+	case []interface{}:
+		if n := len(fields); n&0x1 == 1 { // odd number
+			fields = fields[:n-1]
+		}
+		dst = appendFieldList(dst, fields, stack)
+	case map[string]interface{}:
+		keys := make([]string, 0, len(fields))
+		for key := range fields {
+			keys = append(keys, key)
+		}
+		sort.Strings(keys)
+		kv := make([]interface{}, 2)
+		for _, key := range keys {
+			kv[0], kv[1] = key, fields[key]
+			dst = appendFieldList(dst, kv, stack)
+		}
 	}
-	sort.Strings(keys)
-	for _, key := range keys {
-		dst = enc.AppendKey(dst, key)
-		val := fields[key]
+	return dst
+}
+
+func appendFieldList(dst []byte, kvList []interface{}, stack bool) []byte {
+	for i, n := 0, len(kvList); i < n; i += 2 {
+		key, val := kvList[i], kvList[i+1]
+		if key, ok := key.(string); ok {
+			dst = enc.AppendKey(dst, key)
+		} else {
+			continue
+		}
 		if val, ok := val.(LogObjectMarshaler); ok {
 			e := newEvent(nil, 0)
 			e.buf = e.buf[:0]
@@ -29,8 +56,7 @@ func appendFields(dst []byte, fields map[string]interface{}) []byte {
 		case []byte:
 			dst = enc.AppendBytes(dst, val)
 		case error:
-			marshaled := ErrorMarshalFunc(val)
-			switch m := marshaled.(type) {
+			switch m := ErrorMarshalFunc(val).(type) {
 			case LogObjectMarshaler:
 				e := newEvent(nil, 0)
 				e.buf = e.buf[:0]
@@ -38,17 +64,35 @@ func appendFields(dst []byte, fields map[string]interface{}) []byte {
 				dst = append(dst, e.buf...)
 				putEvent(e)
 			case error:
-				dst = enc.AppendString(dst, m.Error())
+				if m == nil || isNilValue(m) {
+					dst = enc.AppendNil(dst)
+				} else {
+					dst = enc.AppendString(dst, m.Error())
+				}
 			case string:
 				dst = enc.AppendString(dst, m)
 			default:
 				dst = enc.AppendInterface(dst, m)
 			}
+
+			if stack && ErrorStackMarshaler != nil {
+				dst = enc.AppendKey(dst, ErrorStackFieldName)
+				switch m := ErrorStackMarshaler(val).(type) {
+				case nil:
+				case error:
+					if m != nil && !isNilValue(m) {
+						dst = enc.AppendString(dst, m.Error())
+					}
+				case string:
+					dst = enc.AppendString(dst, m)
+				default:
+					dst = enc.AppendInterface(dst, m)
+				}
+			}
 		case []error:
 			dst = enc.AppendArrayStart(dst)
 			for i, err := range val {
-				marshaled := ErrorMarshalFunc(err)
-				switch m := marshaled.(type) {
+				switch m := ErrorMarshalFunc(err).(type) {
 				case LogObjectMarshaler:
 					e := newEvent(nil, 0)
 					e.buf = e.buf[:0]
@@ -56,7 +100,11 @@ func appendFields(dst []byte, fields map[string]interface{}) []byte {
 					dst = append(dst, e.buf...)
 					putEvent(e)
 				case error:
-					dst = enc.AppendString(dst, m.Error())
+					if m == nil || isNilValue(m) {
+						dst = enc.AppendNil(dst)
+					} else {
+						dst = enc.AppendString(dst, m.Error())
+					}
 				case string:
 					dst = enc.AppendString(dst, m)
 				default:
@@ -91,13 +139,13 @@ func appendFields(dst []byte, fields map[string]interface{}) []byte {
 		case uint64:
 			dst = enc.AppendUint64(dst, val)
 		case float32:
-			dst = enc.AppendFloat32(dst, val)
+			dst = enc.AppendFloat32(dst, val, FloatingPointPrecision)
 		case float64:
-			dst = enc.AppendFloat64(dst, val)
+			dst = enc.AppendFloat64(dst, val, FloatingPointPrecision)
 		case time.Time:
 			dst = enc.AppendTime(dst, val, TimeFieldFormat)
 		case time.Duration:
-			dst = enc.AppendDuration(dst, val, DurationFieldUnit, DurationFieldInteger)
+			dst = enc.AppendDuration(dst, val, DurationFieldUnit, DurationFieldInteger, FloatingPointPrecision)
 		case *string:
 			if val != nil {
 				dst = enc.AppendString(dst, *val)
@@ -172,13 +220,13 @@ func appendFields(dst []byte, fields map[string]interface{}) []byte {
 			}
 		case *float32:
 			if val != nil {
-				dst = enc.AppendFloat32(dst, *val)
+				dst = enc.AppendFloat32(dst, *val, FloatingPointPrecision)
 			} else {
 				dst = enc.AppendNil(dst)
 			}
 		case *float64:
 			if val != nil {
-				dst = enc.AppendFloat64(dst, *val)
+				dst = enc.AppendFloat64(dst, *val, FloatingPointPrecision)
 			} else {
 				dst = enc.AppendNil(dst)
 			}
@@ -190,7 +238,7 @@ func appendFields(dst []byte, fields map[string]interface{}) []byte {
 			}
 		case *time.Duration:
 			if val != nil {
-				dst = enc.AppendDuration(dst, *val, DurationFieldUnit, DurationFieldInteger)
+				dst = enc.AppendDuration(dst, *val, DurationFieldUnit, DurationFieldInteger, FloatingPointPrecision)
 			} else {
 				dst = enc.AppendNil(dst)
 			}
@@ -219,13 +267,13 @@ func appendFields(dst []byte, fields map[string]interface{}) []byte {
 		case []uint64:
 			dst = enc.AppendUints64(dst, val)
 		case []float32:
-			dst = enc.AppendFloats32(dst, val)
+			dst = enc.AppendFloats32(dst, val, FloatingPointPrecision)
 		case []float64:
-			dst = enc.AppendFloats64(dst, val)
+			dst = enc.AppendFloats64(dst, val, FloatingPointPrecision)
 		case []time.Time:
 			dst = enc.AppendTimes(dst, val, TimeFieldFormat)
 		case []time.Duration:
-			dst = enc.AppendDurations(dst, val, DurationFieldUnit, DurationFieldInteger)
+			dst = enc.AppendDurations(dst, val, DurationFieldUnit, DurationFieldInteger, FloatingPointPrecision)
 		case nil:
 			dst = enc.AppendNil(dst)
 		case net.IP:
@@ -234,6 +282,8 @@ func appendFields(dst []byte, fields map[string]interface{}) []byte {
 			dst = enc.AppendIPPrefix(dst, val)
 		case net.HardwareAddr:
 			dst = enc.AppendMACAddr(dst, val)
+		case json.RawMessage:
+			dst = appendJSON(dst, val)
 		default:
 			dst = enc.AppendInterface(dst, val)
 		}

globals.go

@@ -1,7 +1,30 @@
 package zerolog
 
-import "time"
-import "sync/atomic"
+import (
+	"bytes"
+	"encoding/json"
+	"strconv"
+	"sync/atomic"
+	"time"
+)
+
+const (
+	// TimeFormatUnix defines a time format that makes time fields to be
+	// serialized as Unix timestamp integers.
+	TimeFormatUnix = ""
+
+	// TimeFormatUnixMs defines a time format that makes time fields to be
+	// serialized as Unix timestamp integers in milliseconds.
+	TimeFormatUnixMs = "UNIXMS"
+
+	// TimeFormatUnixMicro defines a time format that makes time fields to be
+	// serialized as Unix timestamp integers in microseconds.
+	TimeFormatUnixMicro = "UNIXMICRO"
+
+	// TimeFormatUnixNano defines a time format that makes time fields to be
+	// serialized as Unix timestamp integers in nanoseconds.
+	TimeFormatUnixNano = "UNIXNANO"
+)
 
 var (
 	// TimestampFieldName is the field name used for the timestamp field.
@@ -10,6 +33,26 @@ var (
 	// LevelFieldName is the field name used for the level field.
 	LevelFieldName = "level"
 
+	// LevelTraceValue is the value used for the trace level field.
+	LevelTraceValue = "trace"
+	// LevelDebugValue is the value used for the debug level field.
+	LevelDebugValue = "debug"
+	// LevelInfoValue is the value used for the info level field.
+	LevelInfoValue = "info"
+	// LevelWarnValue is the value used for the warn level field.
+	LevelWarnValue = "warn"
+	// LevelErrorValue is the value used for the error level field.
+	LevelErrorValue = "error"
+	// LevelFatalValue is the value used for the fatal level field.
+	LevelFatalValue = "fatal"
+	// LevelPanicValue is the value used for the panic level field.
+	LevelPanicValue = "panic"
+
+	// LevelFieldMarshalFunc allows customization of global level field marshaling.
+	LevelFieldMarshalFunc = func(l Level) string {
+		return l.String()
+	}
+
 	// MessageFieldName is the field name used for the message field.
 	MessageFieldName = "message"
 
@@ -22,9 +65,43 @@ var (
 	// CallerSkipFrameCount is the number of stack frames to skip to find the caller.
 	CallerSkipFrameCount = 2
 
-	// TimeFieldFormat defines the time format of the Time field type.
-	// If set to an empty string, the time is formatted as an UNIX timestamp
-	// as integer.
+	// CallerMarshalFunc allows customization of global caller marshaling
+	CallerMarshalFunc = func(pc uintptr, file string, line int) string {
+		return file + ":" + strconv.Itoa(line)
+	}
+
+	// ErrorStackFieldName is the field name used for error stacks.
+	ErrorStackFieldName = "stack"
+
+	// ErrorStackMarshaler extract the stack from err if any.
+	ErrorStackMarshaler func(err error) interface{}
+
+	// ErrorMarshalFunc allows customization of global error marshaling
+	ErrorMarshalFunc = func(err error) interface{} {
+		return err
+	}
+
+	// InterfaceMarshalFunc allows customization of interface marshaling.
+	// Default: "encoding/json.Marshal" with disabled HTML escaping
+	InterfaceMarshalFunc = func(v interface{}) ([]byte, error) {
+		var buf bytes.Buffer
+		encoder := json.NewEncoder(&buf)
+		encoder.SetEscapeHTML(false)
+		err := encoder.Encode(v)
+		if err != nil {
+			return nil, err
+		}
+		b := buf.Bytes()
+		if len(b) > 0 {
+			// Remove trailing \n which is added by Encode.
+			return b[:len(b)-1], nil
+		}
+		return b, nil
+	}
+
+	// TimeFieldFormat defines the time format of the Time field type. If set to
+	// TimeFormatUnix, TimeFormatUnixMs, TimeFormatUnixMicro or TimeFormatUnixNano, the time is formatted as a UNIX
+	// timestamp as integer.
 	TimeFieldFormat = time.RFC3339
 
 	// TimestampFunc defines the function called to generate a timestamp.
@@ -42,11 +119,48 @@ var (
 	// output. If not set, an error is printed on the stderr. This handler must
 	// be thread safe and non-blocking.
 	ErrorHandler func(err error)
+
+	// DefaultContextLogger is returned from Ctx() if there is no logger associated
+	// with the context.
+	DefaultContextLogger *Logger
+
+	// LevelColors are used by ConsoleWriter's consoleDefaultFormatLevel to color
+	// log levels.
+	LevelColors = map[Level]int{
+		TraceLevel: colorBlue,
+		DebugLevel: 0,
+		InfoLevel:  colorGreen,
+		WarnLevel:  colorYellow,
+		ErrorLevel: colorRed,
+		FatalLevel: colorRed,
+		PanicLevel: colorRed,
+	}
+
+	// FormattedLevels are used by ConsoleWriter's consoleDefaultFormatLevel
+	// for a short level name.
+	FormattedLevels = map[Level]string{
+		TraceLevel: "TRC",
+		DebugLevel: "DBG",
+		InfoLevel:  "INF",
+		WarnLevel:  "WRN",
+		ErrorLevel: "ERR",
+		FatalLevel: "FTL",
+		PanicLevel: "PNC",
+	}
+
+	// TriggerLevelWriterBufferReuseLimit is a limit in bytes that a buffer is dropped
+	// from the TriggerLevelWriter buffer pool if the buffer grows above the limit.
+	TriggerLevelWriterBufferReuseLimit = 64 * 1024
+
+	// FloatingPointPrecision, if set to a value other than -1, controls the number
+	// of digits when formatting float numbers in JSON. See strconv.FormatFloat for
+	// more details.
+	FloatingPointPrecision = -1
 )
 
 var (
-	gLevel          = new(uint32)
-	disableSampling = new(uint32)
+	gLevel          = new(int32)
+	disableSampling = new(int32)
 )
 
 // SetGlobalLevel sets the global override for log level. If this
@@ -54,23 +168,23 @@ var (
 //
 // To globally disable logs, set GlobalLevel to Disabled.
 func SetGlobalLevel(l Level) {
-	atomic.StoreUint32(gLevel, uint32(l))
+	atomic.StoreInt32(gLevel, int32(l))
 }
 
 // GlobalLevel returns the current global log level
 func GlobalLevel() Level {
-	return Level(atomic.LoadUint32(gLevel))
+	return Level(atomic.LoadInt32(gLevel))
 }
 
 // DisableSampling will disable sampling in all Loggers if true.
 func DisableSampling(v bool) {
-	var i uint32
+	var i int32
 	if v {
 		i = 1
 	}
-	atomic.StoreUint32(disableSampling, i)
+	atomic.StoreInt32(disableSampling, i)
 }
 
 func samplingDisabled() bool {
-	return atomic.LoadUint32(disableSampling) == 1
+	return atomic.LoadInt32(disableSampling) == 1
 }

go.mod

@@ -1 +1,12 @@
 module github.com/rs/zerolog
+
+go 1.15
+
+require (
+	github.com/coreos/go-systemd/v22 v22.5.0
+	github.com/mattn/go-colorable v0.1.13
+	github.com/mattn/go-isatty v0.0.19 // indirect
+	github.com/pkg/errors v0.9.1
+	github.com/rs/xid v1.5.0
+	golang.org/x/sys v0.12.0 // indirect
+)

go.sum

@@ -0,0 +1,23 @@
+github.com/coreos/go-systemd/v22 v22.5.0 h1:RrqgGjYQKalulkV8NGVIfkXQf6YYmOyiJKk8iXXhfZs=
+github.com/coreos/go-systemd/v22 v22.5.0/go.mod h1:Y58oyj3AT4RCenI/lSvhwexgC+NSVTIJ3seZv2GcEnc=
+github.com/godbus/dbus/v5 v5.0.4/go.mod h1:xhWf0FNVPg57R7Z0UbKHbJfkEywrmjJnf7w5xrFpKfA=
+github.com/mattn/go-colorable v0.1.12 h1:jF+Du6AlPIjs2BiUiQlKOX0rt3SujHxPnksPKZbaA40=
+github.com/mattn/go-colorable v0.1.12/go.mod h1:u5H1YNBxpqRaxsYJYSkiCWKzEfiAb1Gb520KVy5xxl4=
+github.com/mattn/go-colorable v0.1.13 h1:fFA4WZxdEF4tXPZVKMLwD8oUnCTTo08duU7wxecdEvA=
+github.com/mattn/go-colorable v0.1.13/go.mod h1:7S9/ev0klgBDR4GtXTXX8a3vIGJpMovkB8vQcUbaXHg=
+github.com/mattn/go-isatty v0.0.14 h1:yVuAays6BHfxijgZPzw+3Zlu5yQgKGP2/hcQbHb7S9Y=
+github.com/mattn/go-isatty v0.0.14/go.mod h1:7GGIvUiUoEMVVmxf/4nioHXj79iQHKdU27kJ6hsGG94=
+github.com/mattn/go-isatty v0.0.16/go.mod h1:kYGgaQfpe5nmfYZH+SKPsOc2e4SrIfOl2e/yFXSvRLM=
+github.com/mattn/go-isatty v0.0.19 h1:JITubQf0MOLdlGRuRq+jtsDlekdYPia9ZFsB8h/APPA=
+github.com/mattn/go-isatty v0.0.19/go.mod h1:W+V8PltTTMOvKvAeJH7IuucS94S2C6jfK/D7dTCTo3Y=
+github.com/pkg/errors v0.9.1 h1:FEBLx1zS214owpjy7qsBeixbURkuhQAwrK5UwLGTwt4=
+github.com/pkg/errors v0.9.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
+github.com/rs/xid v1.5.0 h1:mKX4bl4iPYJtEIxp6CYiUuLQ/8DYMoz0PUdtGgMFRVc=
+github.com/rs/xid v1.5.0/go.mod h1:trrq9SKmegXys3aeAKXMUTdJsYXVwGY3RLcfgqegfbg=
+golang.org/x/sys v0.0.0-20210630005230-0f9fa26af87c/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.0.0-20210927094055-39ccf1dd6fa6 h1:foEbQz/B0Oz6YIqu/69kfXPYeFQAuuMYFkjaqXzl5Wo=
+golang.org/x/sys v0.0.0-20210927094055-39ccf1dd6fa6/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.0.0-20220811171246-fbc7d0a398ab/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.6.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.12.0 h1:CM0HF96J0hcLAwsHPJZjfdNzs0gftsLfgKt57wWHJ0o=
+golang.org/x/sys v0.12.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=

go112.go

@@ -0,0 +1,7 @@
+// +build go1.12
+
+package zerolog
+
+// Since go 1.12, some auto generated init functions are hidden from
+// runtime.Caller.
+const contextCallerSkipFrameCount = 2

hlog/hlog.go

@@ -5,12 +5,13 @@ import (
 	"context"
 	"net"
 	"net/http"
+	"strings"
 	"time"
 
 	"github.com/rs/xid"
 	"github.com/rs/zerolog"
+	"github.com/rs/zerolog/hlog/internal/mutil"
 	"github.com/rs/zerolog/log"
-	"github.com/zenazn/goji/web/mutil"
 )
 
 // FromRequest gets the logger in the request's context.
@@ -79,10 +80,39 @@ func RequestHandler(fieldKey string) func(next http.Handler) http.Handler {
 func RemoteAddrHandler(fieldKey string) func(next http.Handler) http.Handler {
 	return func(next http.Handler) http.Handler {
 		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-			if host, _, err := net.SplitHostPort(r.RemoteAddr); err == nil {
+			if r.RemoteAddr != "" {
 				log := zerolog.Ctx(r.Context())
 				log.UpdateContext(func(c zerolog.Context) zerolog.Context {
-					return c.Str(fieldKey, host)
+					return c.Str(fieldKey, r.RemoteAddr)
+				})
+			}
+			next.ServeHTTP(w, r)
+		})
+	}
+}
+
+func getHost(hostPort string) string {
+	if hostPort == "" {
+		return ""
+	}
+
+	host, _, err := net.SplitHostPort(hostPort)
+	if err != nil {
+		return hostPort
+	}
+	return host
+}
+
+// RemoteIPHandler is similar to RemoteAddrHandler, but logs only
+// an IP, not a port.
+func RemoteIPHandler(fieldKey string) func(next http.Handler) http.Handler {
+	return func(next http.Handler) http.Handler {
+		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+			ip := getHost(r.RemoteAddr)
+			if ip != "" {
+				log := zerolog.Ctx(r.Context())
+				log.UpdateContext(func(c zerolog.Context) zerolog.Context {
+					return c.Str(fieldKey, ip)
 				})
 			}
 			next.ServeHTTP(w, r)
@@ -122,6 +152,35 @@ func RefererHandler(fieldKey string) func(next http.Handler) http.Handler {
 	}
 }
 
+// ProtoHandler adds the requests protocol version as a field to the context logger
+// using fieldKey as field Key.
+func ProtoHandler(fieldKey string) func(next http.Handler) http.Handler {
+	return func(next http.Handler) http.Handler {
+		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+			log := zerolog.Ctx(r.Context())
+			log.UpdateContext(func(c zerolog.Context) zerolog.Context {
+				return c.Str(fieldKey, r.Proto)
+			})
+			next.ServeHTTP(w, r)
+		})
+	}
+}
+
+// HTTPVersionHandler is similar to ProtoHandler, but it does not store the "HTTP/"
+// prefix in the protocol name.
+func HTTPVersionHandler(fieldKey string) func(next http.Handler) http.Handler {
+	return func(next http.Handler) http.Handler {
+		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+			proto := strings.TrimPrefix(r.Proto, "HTTP/")
+			log := zerolog.Ctx(r.Context())
+			log.UpdateContext(func(c zerolog.Context) zerolog.Context {
+				return c.Str(fieldKey, proto)
+			})
+			next.ServeHTTP(w, r)
+		})
+	}
+}
+
 type idKey struct{}
 
 // IDFromRequest returns the unique id associated to the request if any.
@@ -138,6 +197,11 @@ func IDFromCtx(ctx context.Context) (id xid.ID, ok bool) {
 	return
 }
 
+// CtxWithID adds the given xid.ID to the context
+func CtxWithID(ctx context.Context, id xid.ID) context.Context {
+	return context.WithValue(ctx, idKey{}, id)
+}
+
 // RequestIDHandler returns a handler setting a unique id to the request which can
 // be gathered using IDFromRequest(req). This generated id is added as a field to the
 // logger using the passed fieldKey as field name. The id is also added as a response
@@ -154,7 +218,7 @@ func RequestIDHandler(fieldKey, headerName string) func(next http.Handler) http.
 			id, ok := IDFromRequest(r)
 			if !ok {
 				id = xid.New()
-				ctx = context.WithValue(ctx, idKey{}, id)
+				ctx = CtxWithID(ctx, id)
 				r = r.WithContext(ctx)
 			}
 			if fieldKey != "" {
@@ -171,14 +235,92 @@ func RequestIDHandler(fieldKey, headerName string) func(next http.Handler) http.
 	}
 }
 
+// CustomHeaderHandler adds given header from request's header as a field to
+// the context's logger using fieldKey as field key.
+func CustomHeaderHandler(fieldKey, header string) func(next http.Handler) http.Handler {
+	return func(next http.Handler) http.Handler {
+		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+			if val := r.Header.Get(header); val != "" {
+				log := zerolog.Ctx(r.Context())
+				log.UpdateContext(func(c zerolog.Context) zerolog.Context {
+					return c.Str(fieldKey, val)
+				})
+			}
+			next.ServeHTTP(w, r)
+		})
+	}
+}
+
+// EtagHandler adds Etag header from response's header as a field to
+// the context's logger using fieldKey as field key.
+func EtagHandler(fieldKey string) func(next http.Handler) http.Handler {
+	return func(next http.Handler) http.Handler {
+		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+			defer func() {
+				etag := w.Header().Get("Etag")
+				if etag != "" {
+					etag = strings.ReplaceAll(etag, `"`, "")
+					log := zerolog.Ctx(r.Context())
+					log.UpdateContext(func(c zerolog.Context) zerolog.Context {
+						return c.Str(fieldKey, etag)
+					})
+				}
+			}()
+			next.ServeHTTP(w, r)
+		})
+	}
+}
+
+func ResponseHeaderHandler(fieldKey, headerName string) func(next http.Handler) http.Handler {
+	return func(next http.Handler) http.Handler {
+		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+			defer func() {
+				value := w.Header().Get(headerName)
+				if value != "" {
+					log := zerolog.Ctx(r.Context())
+					log.UpdateContext(func(c zerolog.Context) zerolog.Context {
+						return c.Str(fieldKey, value)
+					})
+				}
+			}()
+			next.ServeHTTP(w, r)
+		})
+	}
+}
+
 // AccessHandler returns a handler that call f after each request.
 func AccessHandler(f func(r *http.Request, status, size int, duration time.Duration)) func(next http.Handler) http.Handler {
 	return func(next http.Handler) http.Handler {
 		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 			start := time.Now()
 			lw := mutil.WrapWriter(w)
+			defer func() {
+				f(r, lw.Status(), lw.BytesWritten(), time.Since(start))
+			}()
 			next.ServeHTTP(lw, r)
-			f(r, lw.Status(), lw.BytesWritten(), time.Since(start))
+		})
+	}
+}
+
+// HostHandler adds the request's host as a field to the context's logger
+// using fieldKey as field key. If trimPort is set to true, then port is
+// removed from the host.
+func HostHandler(fieldKey string, trimPort ...bool) func(next http.Handler) http.Handler {
+	return func(next http.Handler) http.Handler {
+		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+			var host string
+			if len(trimPort) > 0 && trimPort[0] {
+				host = getHost(r.Host)
+			} else {
+				host = r.Host
+			}
+			if host != "" {
+				log := zerolog.Ctx(r.Context())
+				log.UpdateContext(func(c zerolog.Context) zerolog.Context {
+					return c.Str(fieldKey, host)
+				})
+			}
+			next.ServeHTTP(w, r)
 		})
 	}
 }

hlog/hlog_example_test.go

@@ -48,8 +48,8 @@ func Example_handler() {
 	// Install the logger handler with default output on the console
 	c = c.Append(hlog.NewHandler(log))
 
-	// Install some provided extra handler to set some request's context fields.
-	// Thanks to those handler, all our logs will come with some pre-populated fields.
+	// Install some provided extra handlers to set some request's context fields.
+	// Thanks to those handlers, all our logs will come with some pre-populated fields.
 	c = c.Append(hlog.RemoteAddrHandler("ip"))
 	c = c.Append(hlog.UserAgentHandler("user_agent"))
 	c = c.Append(hlog.RefererHandler("referer"))
@@ -63,11 +63,11 @@ func Example_handler() {
 		hlog.FromRequest(r).Info().
 			Str("user", "current user").
 			Str("status", "ok").
-			Msg("Something happend")
+			Msg("Something happened")
 	}))
 	http.Handle("/", h)
 
 	h.ServeHTTP(httptest.NewRecorder(), &http.Request{})
 
-	// Output: {"level":"info","role":"my-service","host":"local-hostname","user":"current user","status":"ok","time":"2001-02-03T04:05:06Z","message":"Something happend"}
+	// Output: {"level":"info","role":"my-service","host":"local-hostname","user":"current user","status":"ok","time":"2001-02-03T04:05:06Z","message":"Something happened"}
 }

hlog/hlog_test.go

@@ -1,19 +1,20 @@
+//go:build go1.7
 // +build go1.7
 
 package hlog
 
 import (
 	"bytes"
+	"context"
 	"fmt"
-	"io/ioutil"
+	"io"
 	"net/http"
+	"net/http/httptest"
 	"net/url"
+	"reflect"
 	"testing"
 
-	"reflect"
-
-	"net/http/httptest"
-
+	"github.com/rs/xid"
 	"github.com/rs/zerolog"
 	"github.com/rs/zerolog/internal/cbor"
 )
@@ -100,7 +101,7 @@ func TestRemoteAddrHandler(t *testing.T) {
 	}))
 	h = NewHandler(zerolog.New(out))(h)
 	h.ServeHTTP(nil, r)
-	if want, got := `{"ip":"1.2.3.4"}`+"\n", decodeIfBinary(out); want != got {
+	if want, got := `{"ip":"1.2.3.4:1234"}`+"\n", decodeIfBinary(out); want != got {
 		t.Errorf("Invalid log output, got: %s, want: %s", got, want)
 	}
 }
@@ -116,6 +117,38 @@ func TestRemoteAddrHandlerIPv6(t *testing.T) {
 	}))
 	h = NewHandler(zerolog.New(out))(h)
 	h.ServeHTTP(nil, r)
+	if want, got := `{"ip":"[2001:db8:a0b:12f0::1]:1234"}`+"\n", decodeIfBinary(out); want != got {
+		t.Errorf("Invalid log output, got: %s, want: %s", got, want)
+	}
+}
+
+func TestRemoteIPHandler(t *testing.T) {
+	out := &bytes.Buffer{}
+	r := &http.Request{
+		RemoteAddr: "1.2.3.4:1234",
+	}
+	h := RemoteIPHandler("ip")(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		l := FromRequest(r)
+		l.Log().Msg("")
+	}))
+	h = NewHandler(zerolog.New(out))(h)
+	h.ServeHTTP(nil, r)
+	if want, got := `{"ip":"1.2.3.4"}`+"\n", decodeIfBinary(out); want != got {
+		t.Errorf("Invalid log output, got: %s, want: %s", got, want)
+	}
+}
+
+func TestRemoteIPHandlerIPv6(t *testing.T) {
+	out := &bytes.Buffer{}
+	r := &http.Request{
+		RemoteAddr: "[2001:db8:a0b:12f0::1]:1234",
+	}
+	h := RemoteIPHandler("ip")(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		l := FromRequest(r)
+		l.Log().Msg("")
+	}))
+	h = NewHandler(zerolog.New(out))(h)
+	h.ServeHTTP(nil, r)
 	if want, got := `{"ip":"2001:db8:a0b:12f0::1"}`+"\n", decodeIfBinary(out); want != got {
 		t.Errorf("Invalid log output, got: %s, want: %s", got, want)
 	}
@@ -182,6 +215,96 @@ func TestRequestIDHandler(t *testing.T) {
 	h.ServeHTTP(httptest.NewRecorder(), r)
 }
 
+func TestCustomHeaderHandler(t *testing.T) {
+	out := &bytes.Buffer{}
+	r := &http.Request{
+		Header: http.Header{
+			"X-Request-Id": []string{"514bbe5bb5251c92bd07a9846f4a1ab6"},
+		},
+	}
+	h := CustomHeaderHandler("reqID", "X-Request-Id")(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		l := FromRequest(r)
+		l.Log().Msg("")
+	}))
+	h = NewHandler(zerolog.New(out))(h)
+	h.ServeHTTP(nil, r)
+	if want, got := `{"reqID":"514bbe5bb5251c92bd07a9846f4a1ab6"}`+"\n", decodeIfBinary(out); want != got {
+		t.Errorf("Invalid log output, got: %s, want: %s", got, want)
+	}
+}
+
+func TestEtagHandler(t *testing.T) {
+	out := &bytes.Buffer{}
+	w := httptest.NewRecorder()
+	r := &http.Request{}
+	h := EtagHandler("etag")(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.Header().Set("Etag", `"abcdef"`)
+		w.WriteHeader(http.StatusOK)
+	}))
+	h2 := http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		h.ServeHTTP(w, r)
+		l := FromRequest(r)
+		l.Log().Msg("")
+	})
+	h3 := NewHandler(zerolog.New(out))(h2)
+	h3.ServeHTTP(w, r)
+	if want, got := `{"etag":"abcdef"}`+"\n", decodeIfBinary(out); want != got {
+		t.Errorf("Invalid log output, got: %s, want: %s", got, want)
+	}
+}
+
+func TestResponseHeaderHandler(t *testing.T) {
+	out := &bytes.Buffer{}
+	w := httptest.NewRecorder()
+	r := &http.Request{}
+	h := ResponseHeaderHandler("encoding", "Content-Encoding")(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.Header().Set("Content-Encoding", `gzip`)
+		w.WriteHeader(http.StatusOK)
+	}))
+	h2 := http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		h.ServeHTTP(w, r)
+		l := FromRequest(r)
+		l.Log().Msg("")
+	})
+	h3 := NewHandler(zerolog.New(out))(h2)
+	h3.ServeHTTP(w, r)
+	if want, got := `{"encoding":"gzip"}`+"\n", decodeIfBinary(out); want != got {
+		t.Errorf("Invalid log output, got: %s, want: %s", got, want)
+	}
+}
+
+func TestProtoHandler(t *testing.T) {
+	out := &bytes.Buffer{}
+	r := &http.Request{
+		Proto: "test",
+	}
+	h := ProtoHandler("proto")(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		l := FromRequest(r)
+		l.Log().Msg("")
+	}))
+	h = NewHandler(zerolog.New(out))(h)
+	h.ServeHTTP(nil, r)
+	if want, got := `{"proto":"test"}`+"\n", decodeIfBinary(out); want != got {
+		t.Errorf("Invalid log output, got: %s, want: %s", got, want)
+	}
+}
+
+func TestHTTPVersionHandler(t *testing.T) {
+	out := &bytes.Buffer{}
+	r := &http.Request{
+		Proto: "HTTP/1.1",
+	}
+	h := HTTPVersionHandler("proto")(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		l := FromRequest(r)
+		l.Log().Msg("")
+	}))
+	h = NewHandler(zerolog.New(out))(h)
+	h.ServeHTTP(nil, r)
+	if want, got := `{"proto":"1.1"}`+"\n", decodeIfBinary(out); want != got {
+		t.Errorf("Invalid log output, got: %s, want: %s", got, want)
+	}
+}
+
 func TestCombinedHandlers(t *testing.T) {
 	out := &bytes.Buffer{}
 	r := &http.Request{
@@ -210,10 +333,10 @@ func BenchmarkHandlers(b *testing.B) {
 	}))
 	h2 := MethodHandler("method")(RequestHandler("request")(h1))
 	handlers := map[string]http.Handler{
-		"Single":           NewHandler(zerolog.New(ioutil.Discard))(h1),
-		"Combined":         NewHandler(zerolog.New(ioutil.Discard))(h2),
-		"SingleDisabled":   NewHandler(zerolog.New(ioutil.Discard).Level(zerolog.Disabled))(h1),
-		"CombinedDisabled": NewHandler(zerolog.New(ioutil.Discard).Level(zerolog.Disabled))(h2),
+		"Single":           NewHandler(zerolog.New(io.Discard))(h1),
+		"Combined":         NewHandler(zerolog.New(io.Discard))(h2),
+		"SingleDisabled":   NewHandler(zerolog.New(io.Discard).Level(zerolog.Disabled))(h1),
+		"CombinedDisabled": NewHandler(zerolog.New(io.Discard).Level(zerolog.Disabled))(h2),
 	}
 	for name := range handlers {
 		h := handlers[name]
@@ -244,3 +367,69 @@ func BenchmarkDataRace(b *testing.B) {
 		}
 	})
 }
+
+func TestCtxWithID(t *testing.T) {
+	ctx := context.Background()
+
+	id, _ := xid.FromString(`c0umremcie6smuu506pg`)
+
+	want := context.Background()
+	want = context.WithValue(want, idKey{}, id)
+
+	if got := CtxWithID(ctx, id); !reflect.DeepEqual(got, want) {
+		t.Errorf("CtxWithID() = %v, want %v", got, want)
+	}
+}
+
+func TestHostHandler(t *testing.T) {
+	out := &bytes.Buffer{}
+	r := &http.Request{Host: "example.com:8080"}
+	h := HostHandler("host")(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		l := FromRequest(r)
+		l.Log().Msg("")
+	}))
+	h = NewHandler(zerolog.New(out))(h)
+	h.ServeHTTP(nil, r)
+	if want, got := `{"host":"example.com:8080"}`+"\n", decodeIfBinary(out); want != got {
+		t.Errorf("Invalid log output, got: %s, want: %s", got, want)
+	}
+}
+
+func TestHostHandlerWithoutPort(t *testing.T) {
+	out := &bytes.Buffer{}
+	r := &http.Request{Host: "example.com:8080"}
+	h := HostHandler("host", true)(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		l := FromRequest(r)
+		l.Log().Msg("")
+	}))
+	h = NewHandler(zerolog.New(out))(h)
+	h.ServeHTTP(nil, r)
+	if want, got := `{"host":"example.com"}`+"\n", decodeIfBinary(out); want != got {
+		t.Errorf("Invalid log output, got: %s, want: %s", got, want)
+	}
+}
+
+func TestGetHost(t *testing.T) {
+	tests := []struct {
+		input    string
+		expected string
+	}{
+		{"", ""},
+		{"example.com:8080", "example.com"},
+		{"example.com", "example.com"},
+		{"invalid", "invalid"},
+		{"192.168.0.1:8080", "192.168.0.1"},
+		{"[2001:0db8:85a3:0000:0000:8a2e:0370:7334]:8080", "2001:0db8:85a3:0000:0000:8a2e:0370:7334"},
+		{"こんにちは.com:8080", "こんにちは.com"},
+	}
+
+	for _, tt := range tests {
+		tt := tt
+		t.Run(tt.input, func(t *testing.T) {
+			result := getHost(tt.input)
+			if tt.expected != result {
+				t.Errorf("Invalid log output, got: %s, want: %s", result, tt.expected)
+			}
+		})
+	}
+}

hlog/internal/mutil/LICENSE

@@ -0,0 +1,20 @@
+Copyright (c) 2014, 2015, 2016 Carl Jackson (carl@avtok.com)
+
+MIT License
+
+Permission is hereby granted, free of charge, to any person obtaining a copy of
+this software and associated documentation files (the "Software"), to deal in
+the Software without restriction, including without limitation the rights to
+use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+the Software, and to permit persons to whom the Software is furnished to do so,
+subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

hlog/internal/mutil/mutil.go

@@ -0,0 +1,6 @@
+// Package mutil contains various functions that are helpful when writing http
+// middleware.
+//
+// It has been vendored from Goji v1.0, with the exception of the code for Go 1.8:
+// https://github.com/zenazn/goji/
+package mutil

hlog/internal/mutil/writer_proxy.go

@@ -0,0 +1,154 @@
+package mutil
+
+import (
+	"bufio"
+	"io"
+	"net"
+	"net/http"
+)
+
+// WriterProxy is a proxy around an http.ResponseWriter that allows you to hook
+// into various parts of the response process.
+type WriterProxy interface {
+	http.ResponseWriter
+	// Status returns the HTTP status of the request, or 0 if one has not
+	// yet been sent.
+	Status() int
+	// BytesWritten returns the total number of bytes sent to the client.
+	BytesWritten() int
+	// Tee causes the response body to be written to the given io.Writer in
+	// addition to proxying the writes through. Only one io.Writer can be
+	// tee'd to at once: setting a second one will overwrite the first.
+	// Writes will be sent to the proxy before being written to this
+	// io.Writer. It is illegal for the tee'd writer to be modified
+	// concurrently with writes.
+	Tee(io.Writer)
+	// Unwrap returns the original proxied target.
+	Unwrap() http.ResponseWriter
+}
+
+// WrapWriter wraps an http.ResponseWriter, returning a proxy that allows you to
+// hook into various parts of the response process.
+func WrapWriter(w http.ResponseWriter) WriterProxy {
+	_, cn := w.(http.CloseNotifier)
+	_, fl := w.(http.Flusher)
+	_, hj := w.(http.Hijacker)
+	_, rf := w.(io.ReaderFrom)
+
+	bw := basicWriter{ResponseWriter: w}
+	if cn && fl && hj && rf {
+		return &fancyWriter{bw}
+	}
+	if fl {
+		return &flushWriter{bw}
+	}
+	return &bw
+}
+
+// basicWriter wraps a http.ResponseWriter that implements the minimal
+// http.ResponseWriter interface.
+type basicWriter struct {
+	http.ResponseWriter
+	wroteHeader bool
+	code        int
+	bytes       int
+	tee         io.Writer
+}
+
+func (b *basicWriter) WriteHeader(code int) {
+	if !b.wroteHeader {
+		b.code = code
+		b.wroteHeader = true
+		b.ResponseWriter.WriteHeader(code)
+	}
+}
+
+func (b *basicWriter) Write(buf []byte) (int, error) {
+	b.WriteHeader(http.StatusOK)
+	n, err := b.ResponseWriter.Write(buf)
+	if b.tee != nil {
+		_, err2 := b.tee.Write(buf[:n])
+		// Prefer errors generated by the proxied writer.
+		if err == nil {
+			err = err2
+		}
+	}
+	b.bytes += n
+	return n, err
+}
+
+func (b *basicWriter) maybeWriteHeader() {
+	if !b.wroteHeader {
+		b.WriteHeader(http.StatusOK)
+	}
+}
+
+func (b *basicWriter) Status() int {
+	return b.code
+}
+
+func (b *basicWriter) BytesWritten() int {
+	return b.bytes
+}
+
+func (b *basicWriter) Tee(w io.Writer) {
+	b.tee = w
+}
+
+func (b *basicWriter) Unwrap() http.ResponseWriter {
+	return b.ResponseWriter
+}
+
+// fancyWriter is a writer that additionally satisfies http.CloseNotifier,
+// http.Flusher, http.Hijacker, and io.ReaderFrom. It exists for the common case
+// of wrapping the http.ResponseWriter that package http gives you, in order to
+// make the proxied object support the full method set of the proxied object.
+type fancyWriter struct {
+	basicWriter
+}
+
+func (f *fancyWriter) CloseNotify() <-chan bool {
+	cn := f.basicWriter.ResponseWriter.(http.CloseNotifier)
+	return cn.CloseNotify()
+}
+
+func (f *fancyWriter) Flush() {
+	fl := f.basicWriter.ResponseWriter.(http.Flusher)
+	fl.Flush()
+}
+
+func (f *fancyWriter) Hijack() (net.Conn, *bufio.ReadWriter, error) {
+	hj := f.basicWriter.ResponseWriter.(http.Hijacker)
+	return hj.Hijack()
+}
+
+func (f *fancyWriter) ReadFrom(r io.Reader) (int64, error) {
+	if f.basicWriter.tee != nil {
+		n, err := io.Copy(&f.basicWriter, r)
+		f.bytes += int(n)
+		return n, err
+	}
+	rf := f.basicWriter.ResponseWriter.(io.ReaderFrom)
+	f.basicWriter.maybeWriteHeader()
+
+	n, err := rf.ReadFrom(r)
+	f.bytes += int(n)
+	return n, err
+}
+
+type flushWriter struct {
+	basicWriter
+}
+
+func (f *flushWriter) Flush() {
+	fl := f.basicWriter.ResponseWriter.(http.Flusher)
+	fl.Flush()
+}
+
+var (
+	_ http.CloseNotifier = &fancyWriter{}
+	_ http.Flusher       = &fancyWriter{}
+	_ http.Hijacker      = &fancyWriter{}
+	_ io.ReaderFrom      = &fancyWriter{}
+	_ http.Flusher       = &flushWriter{}
+)

hook.go

@@ -17,12 +17,16 @@ func (h HookFunc) Run(e *Event, level Level, message string) {
 
 // LevelHook applies a different hook for each level.
 type LevelHook struct {
-	NoLevelHook, DebugHook, InfoHook, WarnHook, ErrorHook, FatalHook, PanicHook Hook
+	NoLevelHook, TraceHook, DebugHook, InfoHook, WarnHook, ErrorHook, FatalHook, PanicHook Hook
 }
 
 // Run implements the Hook interface.
 func (h LevelHook) Run(e *Event, level Level, message string) {
 	switch level {
+	case TraceLevel:
+		if h.TraceHook != nil {
+			h.TraceHook.Run(e, level, message)
+		}
 	case DebugLevel:
 		if h.DebugHook != nil {
 			h.DebugHook.Run(e, level, message)

hook_test.go

@@ -2,10 +2,15 @@ package zerolog
 
 import (
 	"bytes"
-	"io/ioutil"
+	"context"
+	"io"
 	"testing"
 )
 
+type contextKeyType int
+
+var contextKey contextKeyType
+
 var (
 	levelNameHook = HookFunc(func(e *Event, level Level, msg string) {
 		levelName := level.String()
@@ -31,6 +36,12 @@ var (
 	discardHook = HookFunc(func(e *Event, level Level, message string) {
 		e.Discard()
 	})
+	contextHook = HookFunc(func(e *Event, level Level, message string) {
+		contextData, ok := e.GetCtx().Value(contextKey).(string)
+		if ok {
+			e.Str("context-data", contextData)
+		}
+	})
 )
 
 func TestHook(t *testing.T) {
@@ -120,6 +131,29 @@ func TestHook(t *testing.T) {
 			log = log.Hook(discardHook)
 			log.Log().Msg("test message")
 		}},
+		{"Context/Background", `{"level":"info","message":"test message"}` + "\n", func(log Logger) {
+			log = log.Hook(contextHook)
+			log.Info().Ctx(context.Background()).Msg("test message")
+		}},
+		{"Context/nil", `{"level":"info","message":"test message"}` + "\n", func(log Logger) {
+			// passing `nil` where a context is wanted is against
+			// the rules, but people still do it.
+			log = log.Hook(contextHook)
+			log.Info().Ctx(nil).Msg("test message") // nolint
+		}},
+		{"Context/valid", `{"level":"info","context-data":"12345abcdef","message":"test message"}` + "\n", func(log Logger) {
+			ctx := context.Background()
+			ctx = context.WithValue(ctx, contextKey, "12345abcdef")
+			log = log.Hook(contextHook)
+			log.Info().Ctx(ctx).Msg("test message")
+		}},
+		{"Context/With/valid", `{"level":"info","context-data":"12345abcdef","message":"test message"}` + "\n", func(log Logger) {
+			ctx := context.Background()
+			ctx = context.WithValue(ctx, contextKey, "12345abcdef")
+			log = log.Hook(contextHook)
+			log = log.With().Ctx(ctx).Logger()
+			log.Info().Msg("test message")
+		}},
 		{"None", `{"level":"error"}` + "\n", func(log Logger) {
 			log.Error().Msg("")
 		}},
@@ -138,7 +172,7 @@ func TestHook(t *testing.T) {
 }
 
 func BenchmarkHooks(b *testing.B) {
-	logger := New(ioutil.Discard)
+	logger := New(io.Discard)
 	b.ResetTimer()
 	b.Run("Nop/Single", func(b *testing.B) {
 		log := logger.Hook(nopHook)

internal/cbor/base.go

@@ -1,5 +1,13 @@
 package cbor
 
+// JSONMarshalFunc is used to marshal interface to JSON encoded byte slice.
+// Making it package level instead of embedded in Encoder brings
+// some extra efforts at importing, but avoids value copy when the functions
+// of Encoder being invoked.
+// DO REMEMBER to set this variable at importing, or
+// you might get a nil pointer dereference panic at runtime.
+var JSONMarshalFunc func(v interface{}) ([]byte, error)
+
 type Encoder struct{}
 
 // AppendKey adds a key (string) to the binary encoded log message
@@ -8,4 +16,4 @@ func (e Encoder) AppendKey(dst []byte, key string) []byte {
 		dst = e.AppendBeginMarker(dst)
 	}
 	return e.AppendString(dst, key)
-}
+}

internal/cbor/cbor.go

@@ -26,7 +26,8 @@ const (
 	additionalTypeBreak   byte = 31
 
 	// Tag Sub-types.
-	additionalTypeTimestamp byte = 01
+	additionalTypeTimestamp    byte = 01
+	additionalTypeEmbeddedCBOR byte = 63
 
 	// Extended Tags - from https://www.iana.org/assignments/cbor-tags/cbor-tags.xhtml
 	additionalTypeTagNetworkAddr   uint16 = 260
@@ -67,7 +68,7 @@ const (
 var IntegerTimeFieldFormat = time.RFC3339
 
 // NanoTimeFieldFormat indicates the format of timestamp decoded
-// from a float value (time in seconds and nano seconds).
+// from a float value (time in seconds and nanoseconds).
 var NanoTimeFieldFormat = time.RFC3339Nano
 
 func appendCborTypePrefix(dst []byte, major byte, number uint64) []byte {
@@ -91,7 +92,8 @@ func appendCborTypePrefix(dst []byte, major byte, number uint64) []byte {
 		minor = additionalTypeIntUint64
 
 	}
-	dst = append(dst, byte(major|minor))
+
+	dst = append(dst, major|minor)
 	byteCount--
 	for ; byteCount >= 0; byteCount-- {
 		dst = append(dst, byte(number>>(uint(byteCount)*8)))

internal/cbor/decode_stream.go

@@ -5,6 +5,7 @@ package cbor
 import (
 	"bufio"
 	"bytes"
+	"encoding/base64"
 	"fmt"
 	"io"
 	"math"
@@ -43,7 +44,7 @@ func readByte(src *bufio.Reader) byte {
 	return b
 }
 
-func decodeIntAdditonalType(src *bufio.Reader, minor byte) int64 {
+func decodeIntAdditionalType(src *bufio.Reader, minor byte) int64 {
 	val := int64(0)
 	if minor <= 23 {
 		val = int64(minor)
@@ -77,7 +78,7 @@ func decodeInteger(src *bufio.Reader) int64 {
 	if major != majorTypeUnsignedInt && major != majorTypeNegativeInt {
 		panic(fmt.Errorf("Major type is: %d in decodeInteger!! (expected 0 or 1)", major))
 	}
-	val := decodeIntAdditonalType(src, minor)
+	val := decodeIntAdditionalType(src, minor)
 	if major == 0 {
 		return val
 	}
@@ -94,7 +95,7 @@ func decodeFloat(src *bufio.Reader) (float64, int) {
 
 	switch minor {
 	case additionalTypeFloat16:
-		panic(fmt.Errorf("float16 is not suppported in decodeFloat"))
+		panic(fmt.Errorf("float16 is not supported in decodeFloat"))
 
 	case additionalTypeFloat32:
 		pb := readNBytes(src, 4)
@@ -204,7 +205,7 @@ func decodeString(src *bufio.Reader, noQuotes bool) []byte {
 	if !noQuotes {
 		result = append(result, '"')
 	}
-	length := decodeIntAdditonalType(src, minor)
+	length := decodeIntAdditionalType(src, minor)
 	len := int(length)
 	pbs := readNBytes(src, len)
 	result = append(result, pbs...)
@@ -213,6 +214,31 @@ func decodeString(src *bufio.Reader, noQuotes bool) []byte {
 	}
 	return append(result, '"')
 }
+func decodeStringToDataUrl(src *bufio.Reader, mimeType string) []byte {
+	pb := readByte(src)
+	major := pb & maskOutAdditionalType
+	minor := pb & maskOutMajorType
+	if major != majorTypeByteString {
+		panic(fmt.Errorf("Major type is: %d in decodeString", major))
+	}
+	length := decodeIntAdditionalType(src, minor)
+	l := int(length)
+	enc := base64.StdEncoding
+	lEnc := enc.EncodedLen(l)
+	result := make([]byte, len("\"data:;base64,\"")+len(mimeType)+lEnc)
+	dest := result
+	u := copy(dest, "\"data:")
+	dest = dest[u:]
+	u = copy(dest, mimeType)
+	dest = dest[u:]
+	u = copy(dest, ";base64,")
+	dest = dest[u:]
+	pbs := readNBytes(src, l)
+	enc.Encode(dest, pbs)
+	dest = dest[lEnc:]
+	dest[0] = '"'
+	return result
+}
 
 func decodeUTF8String(src *bufio.Reader) []byte {
 	pb := readByte(src)
@@ -222,7 +248,7 @@ func decodeUTF8String(src *bufio.Reader) []byte {
 		panic(fmt.Errorf("Major type is: %d in decodeUTF8String", major))
 	}
 	result := []byte{'"'}
-	length := decodeIntAdditonalType(src, minor)
+	length := decodeIntAdditionalType(src, minor)
 	len := int(length)
 	pbs := readNBytes(src, len)
 
@@ -238,7 +264,7 @@ func decodeUTF8String(src *bufio.Reader) []byte {
 			return append(dst, '"')
 		}
 	}
-	// The string has no need for encoding an therefore is directly
+	// The string has no need for encoding and therefore is directly
 	// appended to the byte slice.
 	result = append(result, pbs...)
 	return append(result, '"')
@@ -257,7 +283,7 @@ func array2Json(src *bufio.Reader, dst io.Writer) {
 	if minor == additionalTypeInfiniteCount {
 		unSpecifiedCount = true
 	} else {
-		length := decodeIntAdditonalType(src, minor)
+		length := decodeIntAdditionalType(src, minor)
 		len = int(length)
 	}
 	for i := 0; unSpecifiedCount || i < len; i++ {
@@ -266,7 +292,7 @@ func array2Json(src *bufio.Reader, dst io.Writer) {
 			if e != nil {
 				panic(e)
 			}
-			if pb[0] == byte(majorTypeSimpleAndFloat|additionalTypeBreak) {
+			if pb[0] == majorTypeSimpleAndFloat|additionalTypeBreak {
 				readByte(src)
 				break
 			}
@@ -277,7 +303,7 @@ func array2Json(src *bufio.Reader, dst io.Writer) {
 			if e != nil {
 				panic(e)
 			}
-			if pb[0] == byte(majorTypeSimpleAndFloat|additionalTypeBreak) {
+			if pb[0] == majorTypeSimpleAndFloat|additionalTypeBreak {
 				readByte(src)
 				break
 			}
@@ -301,7 +327,7 @@ func map2Json(src *bufio.Reader, dst io.Writer) {
 	if minor == additionalTypeInfiniteCount {
 		unSpecifiedCount = true
 	} else {
-		length := decodeIntAdditonalType(src, minor)
+		length := decodeIntAdditionalType(src, minor)
 		len = int(length)
 	}
 	dst.Write([]byte{'{'})
@@ -311,7 +337,7 @@ func map2Json(src *bufio.Reader, dst io.Writer) {
 			if e != nil {
 				panic(e)
 			}
-			if pb[0] == byte(majorTypeSimpleAndFloat|additionalTypeBreak) {
+			if pb[0] == majorTypeSimpleAndFloat|additionalTypeBreak {
 				readByte(src)
 				break
 			}
@@ -326,7 +352,7 @@ func map2Json(src *bufio.Reader, dst io.Writer) {
 				if e != nil {
 					panic(e)
 				}
-				if pb[0] == byte(majorTypeSimpleAndFloat|additionalTypeBreak) {
+				if pb[0] == majorTypeSimpleAndFloat|additionalTypeBreak {
 					readByte(src)
 					break
 				}
@@ -349,10 +375,24 @@ func decodeTagData(src *bufio.Reader) []byte {
 	switch minor {
 	case additionalTypeTimestamp:
 		return decodeTimeStamp(src)
+	case additionalTypeIntUint8:
+		val := decodeIntAdditionalType(src, minor)
+		switch byte(val) {
+		case additionalTypeEmbeddedCBOR:
+			pb := readByte(src)
+			dataMajor := pb & maskOutAdditionalType
+			if dataMajor != majorTypeByteString {
+				panic(fmt.Errorf("Unsupported embedded Type: %d in decodeEmbeddedCBOR", dataMajor))
+			}
+			src.UnreadByte()
+			return decodeStringToDataUrl(src, "application/cbor")
+		default:
+			panic(fmt.Errorf("Unsupported Additional Tag Type: %d in decodeTagData", val))
+		}
 
 	// Tag value is larger than 256 (so uint16).
 	case additionalTypeIntUint16:
-		val := decodeIntAdditonalType(src, minor)
+		val := decodeIntAdditionalType(src, minor)
 
 		switch uint16(val) {
 		case additionalTypeEmbeddedJSON:
@@ -383,7 +423,7 @@ func decodeTagData(src *bufio.Reader) []byte {
 
 		case additionalTypeTagNetworkPrefix:
 			pb := readByte(src)
-			if pb != byte(majorTypeMap|0x1) {
+			if pb != majorTypeMap|0x1 {
 				panic(fmt.Errorf("IP Prefix is NOT of MAP of 1 elements as expected"))
 			}
 			octets := decodeString(src, true)

internal/cbor/string.go

@@ -1,12 +1,14 @@
 package cbor
 
+import "fmt"
+
 // AppendStrings encodes and adds an array of strings to the dst byte array.
 func (e Encoder) AppendStrings(dst []byte, vals []string) []byte {
 	major := majorTypeArray
 	l := len(vals)
 	if l <= additionalMax {
 		lb := byte(l)
-		dst = append(dst, byte(major|lb))
+		dst = append(dst, major|lb)
 	} else {
 		dst = appendCborTypePrefix(dst, major, uint64(l))
 	}
@@ -23,13 +25,38 @@ func (Encoder) AppendString(dst []byte, s string) []byte {
 	l := len(s)
 	if l <= additionalMax {
 		lb := byte(l)
-		dst = append(dst, byte(major|lb))
+		dst = append(dst, major|lb)
 	} else {
 		dst = appendCborTypePrefix(dst, majorTypeUtf8String, uint64(l))
 	}
 	return append(dst, s...)
 }
 
+// AppendStringers encodes and adds an array of Stringer values
+// to the dst byte array.
+func (e Encoder) AppendStringers(dst []byte, vals []fmt.Stringer) []byte {
+	if len(vals) == 0 {
+		return e.AppendArrayEnd(e.AppendArrayStart(dst))
+	}
+	dst = e.AppendArrayStart(dst)
+	dst = e.AppendStringer(dst, vals[0])
+	if len(vals) > 1 {
+		for _, val := range vals[1:] {
+			dst = e.AppendStringer(dst, val)
+		}
+	}
+	return e.AppendArrayEnd(dst)
+}
+
+// AppendStringer encodes and adds the Stringer value to the dst
+// byte array.
+func (e Encoder) AppendStringer(dst []byte, val fmt.Stringer) []byte {
+	if val == nil {
+		return e.AppendNil(dst)
+	}
+	return e.AppendString(dst, val.String())
+}
+
 // AppendBytes encodes and adds an array of bytes to the dst byte array.
 func (Encoder) AppendBytes(dst, s []byte) []byte {
 	major := majorTypeByteString
@@ -37,7 +64,7 @@ func (Encoder) AppendBytes(dst, s []byte) []byte {
 	l := len(s)
 	if l <= additionalMax {
 		lb := byte(l)
-		dst = append(dst, byte(major|lb))
+		dst = append(dst, major|lb)
 	} else {
 		dst = appendCborTypePrefix(dst, major, uint64(l))
 	}
@@ -50,7 +77,7 @@ func AppendEmbeddedJSON(dst, s []byte) []byte {
 	minor := additionalTypeEmbeddedJSON
 
 	// Append the TAG to indicate this is Embedded JSON.
-	dst = append(dst, byte(major|additionalTypeIntUint16))
+	dst = append(dst, major|additionalTypeIntUint16)
 	dst = append(dst, byte(minor>>8))
 	dst = append(dst, byte(minor&0xff))
 
@@ -60,7 +87,29 @@ func AppendEmbeddedJSON(dst, s []byte) []byte {
 	l := len(s)
 	if l <= additionalMax {
 		lb := byte(l)
-		dst = append(dst, byte(major|lb))
+		dst = append(dst, major|lb)
+	} else {
+		dst = appendCborTypePrefix(dst, major, uint64(l))
+	}
+	return append(dst, s...)
+}
+
+// AppendEmbeddedCBOR adds a tag and embeds input CBOR as such.
+func AppendEmbeddedCBOR(dst, s []byte) []byte {
+	major := majorTypeTags
+	minor := additionalTypeEmbeddedCBOR
+
+	// Append the TAG to indicate this is Embedded JSON.
+	dst = append(dst, major|additionalTypeIntUint8)
+	dst = append(dst, minor)
+
+	// Append the CBOR Object as Byte String.
+	major = majorTypeByteString
+
+	l := len(s)
+	if l <= additionalMax {
+		lb := byte(l)
+		dst = append(dst, major|lb)
 	} else {
 		dst = appendCborTypePrefix(dst, major, uint64(l))
 	}

internal/cbor/time.go

@@ -7,7 +7,7 @@ import (
 func appendIntegerTimestamp(dst []byte, t time.Time) []byte {
 	major := majorTypeTags
 	minor := additionalTypeTimestamp
-	dst = append(dst, byte(major|minor))
+	dst = append(dst, major|minor)
 	secs := t.Unix()
 	var val uint64
 	if secs < 0 {
@@ -17,19 +17,19 @@ func appendIntegerTimestamp(dst []byte, t time.Time) []byte {
 		major = majorTypeUnsignedInt
 		val = uint64(secs)
 	}
-	dst = appendCborTypePrefix(dst, major, uint64(val))
+	dst = appendCborTypePrefix(dst, major, val)
 	return dst
 }
 
 func (e Encoder) appendFloatTimestamp(dst []byte, t time.Time) []byte {
 	major := majorTypeTags
 	minor := additionalTypeTimestamp
-	dst = append(dst, byte(major|minor))
+	dst = append(dst, major|minor)
 	secs := t.Unix()
 	nanos := t.Nanosecond()
 	var val float64
-	val = float64(secs)*1.0 + float64(nanos)*1E-9
-	return e.AppendFloat64(dst, val)
+	val = float64(secs)*1.0 + float64(nanos)*1e-9
+	return e.AppendFloat64(dst, val, -1)
 }
 
 // AppendTime encodes and adds a timestamp to the dst byte array.
@@ -50,7 +50,7 @@ func (e Encoder) AppendTimes(dst []byte, vals []time.Time, unused string) []byte
 	}
 	if l <= additionalMax {
 		lb := byte(l)
-		dst = append(dst, byte(major|lb))
+		dst = append(dst, major|lb)
 	} else {
 		dst = appendCborTypePrefix(dst, major, uint64(l))
 	}
@@ -64,17 +64,17 @@ func (e Encoder) AppendTimes(dst []byte, vals []time.Time, unused string) []byte
 // AppendDuration encodes and adds a duration to the dst byte array.
 // useInt field indicates whether to store the duration as seconds (integer) or
 // as seconds+nanoseconds (float).
-func (e Encoder) AppendDuration(dst []byte, d time.Duration, unit time.Duration, useInt bool) []byte {
+func (e Encoder) AppendDuration(dst []byte, d time.Duration, unit time.Duration, useInt bool, unused int) []byte {
 	if useInt {
 		return e.AppendInt64(dst, int64(d/unit))
 	}
-	return e.AppendFloat64(dst, float64(d)/float64(unit))
+	return e.AppendFloat64(dst, float64(d)/float64(unit), unused)
 }
 
 // AppendDurations encodes and adds an array of durations to the dst byte array.
 // useInt field indicates whether to store the duration as seconds (integer) or
 // as seconds+nanoseconds (float).
-func (e Encoder) AppendDurations(dst []byte, vals []time.Duration, unit time.Duration, useInt bool) []byte {
+func (e Encoder) AppendDurations(dst []byte, vals []time.Duration, unit time.Duration, useInt bool, unused int) []byte {
 	major := majorTypeArray
 	l := len(vals)
 	if l == 0 {
@@ -82,12 +82,12 @@ func (e Encoder) AppendDurations(dst []byte, vals []time.Duration, unit time.Dur
 	}
 	if l <= additionalMax {
 		lb := byte(l)
-		dst = append(dst, byte(major|lb))
+		dst = append(dst, major|lb)
 	} else {
 		dst = appendCborTypePrefix(dst, major, uint64(l))
 	}
 	for _, d := range vals {
-		dst = e.AppendDuration(dst, d, unit, useInt)
+		dst = e.AppendDuration(dst, d, unit, useInt, unused)
 	}
 	return dst
 }

internal/cbor/types.go

@@ -1,42 +1,42 @@
 package cbor
 
 import (
-	"encoding/json"
 	"fmt"
 	"math"
 	"net"
+	"reflect"
 )
 
 // AppendNil inserts a 'Nil' object into the dst byte array.
 func (Encoder) AppendNil(dst []byte) []byte {
-	return append(dst, byte(majorTypeSimpleAndFloat|additionalTypeNull))
+	return append(dst, majorTypeSimpleAndFloat|additionalTypeNull)
 }
 
 // AppendBeginMarker inserts a map start into the dst byte array.
 func (Encoder) AppendBeginMarker(dst []byte) []byte {
-	return append(dst, byte(majorTypeMap|additionalTypeInfiniteCount))
+	return append(dst, majorTypeMap|additionalTypeInfiniteCount)
 }
 
 // AppendEndMarker inserts a map end into the dst byte array.
 func (Encoder) AppendEndMarker(dst []byte) []byte {
-	return append(dst, byte(majorTypeSimpleAndFloat|additionalTypeBreak))
+	return append(dst, majorTypeSimpleAndFloat|additionalTypeBreak)
 }
 
 // AppendObjectData takes an object in form of a byte array and appends to dst.
 func (Encoder) AppendObjectData(dst []byte, o []byte) []byte {
-        // BeginMarker is present in the dst, which
-        // should not be copied when appending to existing data.
-        return append(dst, o[1:]...)
+	// BeginMarker is present in the dst, which
+	// should not be copied when appending to existing data.
+	return append(dst, o[1:]...)
 }
 
 // AppendArrayStart adds markers to indicate the start of an array.
 func (Encoder) AppendArrayStart(dst []byte) []byte {
-	return append(dst, byte(majorTypeArray|additionalTypeInfiniteCount))
+	return append(dst, majorTypeArray|additionalTypeInfiniteCount)
 }
 
 // AppendArrayEnd adds markers to indicate the end of an array.
 func (Encoder) AppendArrayEnd(dst []byte) []byte {
-	return append(dst, byte(majorTypeSimpleAndFloat|additionalTypeBreak))
+	return append(dst, majorTypeSimpleAndFloat|additionalTypeBreak)
 }
 
 // AppendArrayDelim adds markers to indicate end of a particular array element.
@@ -57,7 +57,7 @@ func (Encoder) AppendBool(dst []byte, val bool) []byte {
 	if val {
 		b = additionalTypeBoolTrue
 	}
-	return append(dst, byte(majorTypeSimpleAndFloat|b))
+	return append(dst, majorTypeSimpleAndFloat|b)
 }
 
 // AppendBools encodes and inserts an array of boolean values into the dst byte array.
@@ -69,7 +69,7 @@ func (e Encoder) AppendBools(dst []byte, vals []bool) []byte {
 	}
 	if l <= additionalMax {
 		lb := byte(l)
-		dst = append(dst, byte(major|lb))
+		dst = append(dst, major|lb)
 	} else {
 		dst = appendCborTypePrefix(dst, major, uint64(l))
 	}
@@ -89,7 +89,7 @@ func (Encoder) AppendInt(dst []byte, val int) []byte {
 	}
 	if contentVal <= additionalMax {
 		lb := byte(contentVal)
-		dst = append(dst, byte(major|lb))
+		dst = append(dst, major|lb)
 	} else {
 		dst = appendCborTypePrefix(dst, major, uint64(contentVal))
 	}
@@ -105,7 +105,7 @@ func (e Encoder) AppendInts(dst []byte, vals []int) []byte {
 	}
 	if l <= additionalMax {
 		lb := byte(l)
-		dst = append(dst, byte(major|lb))
+		dst = append(dst, major|lb)
 	} else {
 		dst = appendCborTypePrefix(dst, major, uint64(l))
 	}
@@ -129,7 +129,7 @@ func (e Encoder) AppendInts8(dst []byte, vals []int8) []byte {
 	}
 	if l <= additionalMax {
 		lb := byte(l)
-		dst = append(dst, byte(major|lb))
+		dst = append(dst, major|lb)
 	} else {
 		dst = appendCborTypePrefix(dst, major, uint64(l))
 	}
@@ -153,7 +153,7 @@ func (e Encoder) AppendInts16(dst []byte, vals []int16) []byte {
 	}
 	if l <= additionalMax {
 		lb := byte(l)
-		dst = append(dst, byte(major|lb))
+		dst = append(dst, major|lb)
 	} else {
 		dst = appendCborTypePrefix(dst, major, uint64(l))
 	}
@@ -177,7 +177,7 @@ func (e Encoder) AppendInts32(dst []byte, vals []int32) []byte {
 	}
 	if l <= additionalMax {
 		lb := byte(l)
-		dst = append(dst, byte(major|lb))
+		dst = append(dst, major|lb)
 	} else {
 		dst = appendCborTypePrefix(dst, major, uint64(l))
 	}
@@ -197,7 +197,7 @@ func (Encoder) AppendInt64(dst []byte, val int64) []byte {
 	}
 	if contentVal <= additionalMax {
 		lb := byte(contentVal)
-		dst = append(dst, byte(major|lb))
+		dst = append(dst, major|lb)
 	} else {
 		dst = appendCborTypePrefix(dst, major, uint64(contentVal))
 	}
@@ -213,7 +213,7 @@ func (e Encoder) AppendInts64(dst []byte, vals []int64) []byte {
 	}
 	if l <= additionalMax {
 		lb := byte(l)
-		dst = append(dst, byte(major|lb))
+		dst = append(dst, major|lb)
 	} else {
 		dst = appendCborTypePrefix(dst, major, uint64(l))
 	}
@@ -237,7 +237,7 @@ func (e Encoder) AppendUints(dst []byte, vals []uint) []byte {
 	}
 	if l <= additionalMax {
 		lb := byte(l)
-		dst = append(dst, byte(major|lb))
+		dst = append(dst, major|lb)
 	} else {
 		dst = appendCborTypePrefix(dst, major, uint64(l))
 	}
@@ -261,7 +261,7 @@ func (e Encoder) AppendUints8(dst []byte, vals []uint8) []byte {
 	}
 	if l <= additionalMax {
 		lb := byte(l)
-		dst = append(dst, byte(major|lb))
+		dst = append(dst, major|lb)
 	} else {
 		dst = appendCborTypePrefix(dst, major, uint64(l))
 	}
@@ -285,7 +285,7 @@ func (e Encoder) AppendUints16(dst []byte, vals []uint16) []byte {
 	}
 	if l <= additionalMax {
 		lb := byte(l)
-		dst = append(dst, byte(major|lb))
+		dst = append(dst, major|lb)
 	} else {
 		dst = appendCborTypePrefix(dst, major, uint64(l))
 	}
@@ -309,7 +309,7 @@ func (e Encoder) AppendUints32(dst []byte, vals []uint32) []byte {
 	}
 	if l <= additionalMax {
 		lb := byte(l)
-		dst = append(dst, byte(major|lb))
+		dst = append(dst, major|lb)
 	} else {
 		dst = appendCborTypePrefix(dst, major, uint64(l))
 	}
@@ -325,9 +325,9 @@ func (Encoder) AppendUint64(dst []byte, val uint64) []byte {
 	contentVal := val
 	if contentVal <= additionalMax {
 		lb := byte(contentVal)
-		dst = append(dst, byte(major|lb))
+		dst = append(dst, major|lb)
 	} else {
-		dst = appendCborTypePrefix(dst, major, uint64(contentVal))
+		dst = appendCborTypePrefix(dst, major, contentVal)
 	}
 	return dst
 }
@@ -341,7 +341,7 @@ func (e Encoder) AppendUints64(dst []byte, vals []uint64) []byte {
 	}
 	if l <= additionalMax {
 		lb := byte(l)
-		dst = append(dst, byte(major|lb))
+		dst = append(dst, major|lb)
 	} else {
 		dst = appendCborTypePrefix(dst, major, uint64(l))
 	}
@@ -352,7 +352,7 @@ func (e Encoder) AppendUints64(dst []byte, vals []uint64) []byte {
 }
 
 // AppendFloat32 encodes and inserts a single precision float value into the dst byte array.
-func (Encoder) AppendFloat32(dst []byte, val float32) []byte {
+func (Encoder) AppendFloat32(dst []byte, val float32, unused int) []byte {
 	switch {
 	case math.IsNaN(float64(val)):
 		return append(dst, "\xfa\x7f\xc0\x00\x00"...)
@@ -368,11 +368,11 @@ func (Encoder) AppendFloat32(dst []byte, val float32) []byte {
 	for i := uint(0); i < 4; i++ {
 		buf[i] = byte(n >> ((3 - i) * 8))
 	}
-	return append(append(dst, byte(major|subType)), buf[0], buf[1], buf[2], buf[3])
+	return append(append(dst, major|subType), buf[0], buf[1], buf[2], buf[3])
 }
 
 // AppendFloats32 encodes and inserts an array of single precision float value into the dst byte array.
-func (e Encoder) AppendFloats32(dst []byte, vals []float32) []byte {
+func (e Encoder) AppendFloats32(dst []byte, vals []float32, unused int) []byte {
 	major := majorTypeArray
 	l := len(vals)
 	if l == 0 {
@@ -380,18 +380,18 @@ func (e Encoder) AppendFloats32(dst []byte, vals []float32) []byte {
 	}
 	if l <= additionalMax {
 		lb := byte(l)
-		dst = append(dst, byte(major|lb))
+		dst = append(dst, major|lb)
 	} else {
 		dst = appendCborTypePrefix(dst, major, uint64(l))
 	}
 	for _, v := range vals {
-		dst = e.AppendFloat32(dst, v)
+		dst = e.AppendFloat32(dst, v, unused)
 	}
 	return dst
 }
 
 // AppendFloat64 encodes and inserts a double precision float value into the dst byte array.
-func (Encoder) AppendFloat64(dst []byte, val float64) []byte {
+func (Encoder) AppendFloat64(dst []byte, val float64, unused int) []byte {
 	switch {
 	case math.IsNaN(val):
 		return append(dst, "\xfb\x7f\xf8\x00\x00\x00\x00\x00\x00"...)
@@ -403,7 +403,7 @@ func (Encoder) AppendFloat64(dst []byte, val float64) []byte {
 	major := majorTypeSimpleAndFloat
 	subType := additionalTypeFloat64
 	n := math.Float64bits(val)
-	dst = append(dst, byte(major|subType))
+	dst = append(dst, major|subType)
 	for i := uint(1); i <= 8; i++ {
 		b := byte(n >> ((8 - i) * 8))
 		dst = append(dst, b)
@@ -412,7 +412,7 @@ func (Encoder) AppendFloat64(dst []byte, val float64) []byte {
 }
 
 // AppendFloats64 encodes and inserts an array of double precision float values into the dst byte array.
-func (e Encoder) AppendFloats64(dst []byte, vals []float64) []byte {
+func (e Encoder) AppendFloats64(dst []byte, vals []float64, unused int) []byte {
 	major := majorTypeArray
 	l := len(vals)
 	if l == 0 {
@@ -420,28 +420,36 @@ func (e Encoder) AppendFloats64(dst []byte, vals []float64) []byte {
 	}
 	if l <= additionalMax {
 		lb := byte(l)
-		dst = append(dst, byte(major|lb))
+		dst = append(dst, major|lb)
 	} else {
 		dst = appendCborTypePrefix(dst, major, uint64(l))
 	}
 	for _, v := range vals {
-		dst = e.AppendFloat64(dst, v)
+		dst = e.AppendFloat64(dst, v, unused)
 	}
 	return dst
 }
 
 // AppendInterface takes an arbitrary object and converts it to JSON and embeds it dst.
 func (e Encoder) AppendInterface(dst []byte, i interface{}) []byte {
-	marshaled, err := json.Marshal(i)
+	marshaled, err := JSONMarshalFunc(i)
 	if err != nil {
 		return e.AppendString(dst, fmt.Sprintf("marshaling error: %v", err))
 	}
 	return AppendEmbeddedJSON(dst, marshaled)
 }
 
+// AppendType appends the parameter type (as a string) to the input byte slice.
+func (e Encoder) AppendType(dst []byte, i interface{}) []byte {
+	if i == nil {
+		return e.AppendString(dst, "<nil>")
+	}
+	return e.AppendString(dst, reflect.TypeOf(i).String())
+}
+
 // AppendIPAddr encodes and inserts an IP Address (IPv4 or IPv6).
 func (e Encoder) AppendIPAddr(dst []byte, ip net.IP) []byte {
-	dst = append(dst, byte(majorTypeTags|additionalTypeIntUint16))
+	dst = append(dst, majorTypeTags|additionalTypeIntUint16)
 	dst = append(dst, byte(additionalTypeTagNetworkAddr>>8))
 	dst = append(dst, byte(additionalTypeTagNetworkAddr&0xff))
 	return e.AppendBytes(dst, ip)
@@ -449,21 +457,21 @@ func (e Encoder) AppendIPAddr(dst []byte, ip net.IP) []byte {
 
 // AppendIPPrefix encodes and inserts an IP Address Prefix (Address + Mask Length).
 func (e Encoder) AppendIPPrefix(dst []byte, pfx net.IPNet) []byte {
-	dst = append(dst, byte(majorTypeTags|additionalTypeIntUint16))
+	dst = append(dst, majorTypeTags|additionalTypeIntUint16)
 	dst = append(dst, byte(additionalTypeTagNetworkPrefix>>8))
 	dst = append(dst, byte(additionalTypeTagNetworkPrefix&0xff))
 
 	// Prefix is a tuple (aka MAP of 1 pair of elements) -
 	// first element is prefix, second is mask length.
-	dst = append(dst, byte(majorTypeMap|0x1))
+	dst = append(dst, majorTypeMap|0x1)
 	dst = e.AppendBytes(dst, pfx.IP)
 	maskLen, _ := pfx.Mask.Size()
 	return e.AppendUint8(dst, uint8(maskLen))
 }
 
-// AppendMACAddr encodes and inserts an Hardware (MAC) address.
+// AppendMACAddr encodes and inserts a Hardware (MAC) address.
 func (e Encoder) AppendMACAddr(dst []byte, ha net.HardwareAddr) []byte {
-	dst = append(dst, byte(majorTypeTags|additionalTypeIntUint16))
+	dst = append(dst, majorTypeTags|additionalTypeIntUint16)
 	dst = append(dst, byte(additionalTypeTagNetworkAddr>>8))
 	dst = append(dst, byte(additionalTypeTagNetworkAddr&0xff))
 	return e.AppendBytes(dst, ha)
@@ -471,7 +479,7 @@ func (e Encoder) AppendMACAddr(dst []byte, ha net.HardwareAddr) []byte {
 
 // AppendHex adds a TAG and inserts a hex bytes as a string.
 func (e Encoder) AppendHex(dst []byte, val []byte) []byte {
-	dst = append(dst, byte(majorTypeTags|additionalTypeIntUint16))
+	dst = append(dst, majorTypeTags|additionalTypeIntUint16)
 	dst = append(dst, byte(additionalTypeTagHexString>>8))
 	dst = append(dst, byte(additionalTypeTagHexString&0xff))
 	return e.AppendBytes(dst, val)

internal/cbor/types_64_test.go

@@ -0,0 +1,34 @@
+// +build !386
+
+package cbor
+
+import (
+	"encoding/hex"
+	"testing"
+)
+
+var enc2 = Encoder{}
+
+var integerTestCases_64bit = []struct {
+	val    int
+	binary string
+}{
+	// Value in 8 bytes.
+	{0xabcd100000000, "\x1b\x00\x0a\xbc\xd1\x00\x00\x00\x00"},
+	{1000000000000, "\x1b\x00\x00\x00\xe8\xd4\xa5\x10\x00"},
+	// Value in 8 bytes.
+	{-0xabcd100000001, "\x3b\x00\x0a\xbc\xd1\x00\x00\x00\x00"},
+	{-1000000000001, "\x3b\x00\x00\x00\xe8\xd4\xa5\x10\x00"},
+}
+
+func TestAppendInt_64bit(t *testing.T) {
+	for _, tc := range integerTestCases_64bit {
+		s := enc2.AppendInt([]byte{}, tc.val)
+		got := string(s)
+		if got != tc.binary {
+			t.Errorf("AppendInt(0x%x)=0x%s, want: 0x%s",
+				tc.val, hex.EncodeToString(s),
+				hex.EncodeToString([]byte(tc.binary)))
+		}
+	}
+}

internal/cbor/types_test.go

@@ -88,11 +88,8 @@ var integerTestCases = []struct {
 	{0xFFFF, "\x19\xff\xff"},
 	// Value in 4 bytes.
 	{0x10000, "\x1a\x00\x01\x00\x00"},
-	{0xFFFFFFFE, "\x1a\xff\xff\xff\xfe"},
+	{0x7FFFFFFE, "\x1a\x7f\xff\xff\xfe"},
 	{1000000, "\x1a\x00\x0f\x42\x40"},
-	// Value in 8 bytes.
-	{0xabcd100000000, "\x1b\x00\x0a\xbc\xd1\x00\x00\x00\x00"},
-	{1000000000000, "\x1b\x00\x00\x00\xe8\xd4\xa5\x10\x00"},
 	// Negative number test cases.
 	// Value included in the type.
 	{-1, "\x20"},
@@ -116,11 +113,8 @@ var integerTestCases = []struct {
 	{-1000, "\x39\x03\xe7"},
 	// Value in 4 bytes.
 	{-0x10001, "\x3a\x00\x01\x00\x00"},
-	{-0xFFFFFFFE, "\x3a\xff\xff\xff\xfd"},
+	{-0x7FFFFFFE, "\x3a\x7f\xff\xff\xfd"},
 	{-1000000, "\x3a\x00\x0f\x42\x3f"},
-	// Value in 8 bytes.
-	{-0xabcd100000001, "\x3b\x00\x0a\xbc\xd1\x00\x00\x00\x00"},
-	{-1000000000001, "\x3b\x00\x00\x00\xe8\xd4\xa5\x10\x00"},
 }
 
 func TestAppendInt(t *testing.T) {
@@ -175,7 +169,7 @@ var float32TestCases = []struct {
 
 func TestAppendFloat32(t *testing.T) {
 	for _, tc := range float32TestCases {
-		s := enc.AppendFloat32([]byte{}, tc.val)
+		s := enc.AppendFloat32([]byte{}, tc.val, -1)
 		got := string(s)
 		if got != tc.binary {
 			t.Errorf("AppendFloat32(%f)=0x%s, want: 0x%s",
@@ -217,7 +211,7 @@ var macAddrTestCases = []struct {
 	{net.HardwareAddr{0x20, 0x01, 0x0d, 0xb8, 0x85, 0xa3}, "\"20:01:0d:b8:85:a3\"", "\xd9\x01\x04\x46\x20\x01\x0d\xb8\x85\xa3"},
 }
 
-func TestAppendMacAddr(t *testing.T) {
+func TestAppendMACAddr(t *testing.T) {
 	for _, tc := range macAddrTestCases {
 		s := enc.AppendMACAddr([]byte{}, tc.macaddr)
 		got := string(s)
@@ -312,9 +306,9 @@ func BenchmarkAppendFloat(b *testing.B) {
 			for i := 0; i < b.N; i++ {
 				switch str.sz {
 				case 4:
-					_ = enc.AppendFloat32(buf, float32(str.val))
+					_ = enc.AppendFloat32(buf, float32(str.val), -1)
 				case 8:
-					_ = enc.AppendFloat64(buf, str.val)
+					_ = enc.AppendFloat64(buf, str.val, -1)
 				}
 			}
 		})

internal/json/base.go

@@ -1,12 +1,19 @@
 package json
 
+// JSONMarshalFunc is used to marshal interface to JSON encoded byte slice.
+// Making it package level instead of embedded in Encoder brings
+// some extra efforts at importing, but avoids value copy when the functions
+// of Encoder being invoked.
+// DO REMEMBER to set this variable at importing, or
+// you might get a nil pointer dereference panic at runtime.
+var JSONMarshalFunc func(v interface{}) ([]byte, error)
+
 type Encoder struct{}
 
 // AppendKey appends a new key to the output JSON.
 func (e Encoder) AppendKey(dst []byte, key string) []byte {
-	if len(dst) > 1 && dst[len(dst)-1] != '{' {
+	if dst[len(dst)-1] != '{' {
 		dst = append(dst, ',')
 	}
-	dst = e.AppendString(dst, key)
-	return append(dst, ':')
-}
+	return append(e.AppendString(dst, key), ':')
+}

internal/json/string.go

@@ -1,6 +1,9 @@
 package json
 
-import "unicode/utf8"
+import (
+	"fmt"
+	"unicode/utf8"
+)
 
 const hex = "0123456789abcdef"
 
@@ -34,7 +37,7 @@ func (e Encoder) AppendStrings(dst []byte, vals []string) []byte {
 //
 // The operation loops though each byte in the string looking
 // for characters that need json or utf8 encoding. If the string
-// does not need encoding, then the string is appended in it's
+// does not need encoding, then the string is appended in its
 // entirety to the byte slice.
 // If we encounter a byte that does need encoding, switch up
 // the operation and perform a byte-by-byte read-encode-append.
@@ -53,14 +56,39 @@ func (Encoder) AppendString(dst []byte, s string) []byte {
 			return append(dst, '"')
 		}
 	}
-	// The string has no need for encoding an therefore is directly
+	// The string has no need for encoding and therefore is directly
 	// appended to the byte slice.
 	dst = append(dst, s...)
 	// End with a double quote
 	return append(dst, '"')
 }
 
-// appendStringComplex is used by appendString to take over an in
+// AppendStringers encodes the provided Stringer list to json and
+// appends the encoded Stringer list to the input byte slice.
+func (e Encoder) AppendStringers(dst []byte, vals []fmt.Stringer) []byte {
+	if len(vals) == 0 {
+		return append(dst, '[', ']')
+	}
+	dst = append(dst, '[')
+	dst = e.AppendStringer(dst, vals[0])
+	if len(vals) > 1 {
+		for _, val := range vals[1:] {
+			dst = e.AppendStringer(append(dst, ','), val)
+		}
+	}
+	return append(dst, ']')
+}
+
+// AppendStringer encodes the input Stringer to json and appends the
+// encoded Stringer value to the input byte slice.
+func (e Encoder) AppendStringer(dst []byte, val fmt.Stringer) []byte {
+	if val == nil {
+		return e.AppendInterface(dst, nil)
+	}
+	return e.AppendString(dst, val.String())
+}
+
+//// appendStringComplex is used by appendString to take over an in
 // progress JSON string encoding that encountered a character that needs
 // to be encoded.
 func appendStringComplex(dst []byte, s string, i int) []byte {
@@ -71,7 +99,7 @@ func appendStringComplex(dst []byte, s string, i int) []byte {
 			r, size := utf8.DecodeRuneInString(s[i:])
 			if r == utf8.RuneError && size == 1 {
 				// In case of error, first append previous simple characters to
-				// the byte slice if any and append a remplacement character code
+				// the byte slice if any and append a replacement character code
 				// in place of the invalid sequence.
 				if start < i {
 					dst = append(dst, s[start:i]...)

internal/json/time.go

@@ -5,11 +5,26 @@ import (
 	"time"
 )
 
+const (
+	// Import from zerolog/global.go
+	timeFormatUnix      = ""
+	timeFormatUnixMs    = "UNIXMS"
+	timeFormatUnixMicro = "UNIXMICRO"
+	timeFormatUnixNano  = "UNIXNANO"
+)
+
 // AppendTime formats the input time with the given format
 // and appends the encoded string to the input byte slice.
 func (e Encoder) AppendTime(dst []byte, t time.Time, format string) []byte {
-	if format == "" {
+	switch format {
+	case timeFormatUnix:
 		return e.AppendInt64(dst, t.Unix())
+	case timeFormatUnixMs:
+		return e.AppendInt64(dst, t.UnixNano()/1000000)
+	case timeFormatUnixMicro:
+		return e.AppendInt64(dst, t.UnixNano()/1000)
+	case timeFormatUnixNano:
+		return e.AppendInt64(dst, t.UnixNano())
 	}
 	return append(t.AppendFormat(append(dst, '"'), format), '"')
 }
@@ -17,8 +32,15 @@ func (e Encoder) AppendTime(dst []byte, t time.Time, format string) []byte {
 // AppendTimes converts the input times with the given format
 // and appends the encoded string list to the input byte slice.
 func (Encoder) AppendTimes(dst []byte, vals []time.Time, format string) []byte {
-	if format == "" {
+	switch format {
+	case timeFormatUnix:
 		return appendUnixTimes(dst, vals)
+	case timeFormatUnixMs:
+		return appendUnixNanoTimes(dst, vals, 1000000)
+	case timeFormatUnixMicro:
+		return appendUnixNanoTimes(dst, vals, 1000)
+	case timeFormatUnixNano:
+		return appendUnixNanoTimes(dst, vals, 1)
 	}
 	if len(vals) == 0 {
 		return append(dst, '[', ']')
@@ -49,26 +71,41 @@ func appendUnixTimes(dst []byte, vals []time.Time) []byte {
 	return dst
 }
 
-// AppendDuration formats the input duration with the given unit & format
-// and appends the encoded string to the input byte slice.
-func (e Encoder) AppendDuration(dst []byte, d time.Duration, unit time.Duration, useInt bool) []byte {
-	if useInt {
-		return strconv.AppendInt(dst, int64(d/unit), 10)
-	}
-	return e.AppendFloat64(dst, float64(d)/float64(unit))
-}
-
-// AppendDurations formats the input durations with the given unit & format
-// and appends the encoded string list to the input byte slice.
-func (e Encoder) AppendDurations(dst []byte, vals []time.Duration, unit time.Duration, useInt bool) []byte {
+func appendUnixNanoTimes(dst []byte, vals []time.Time, div int64) []byte {
 	if len(vals) == 0 {
 		return append(dst, '[', ']')
 	}
 	dst = append(dst, '[')
-	dst = e.AppendDuration(dst, vals[0], unit, useInt)
+	dst = strconv.AppendInt(dst, vals[0].UnixNano()/div, 10)
 	if len(vals) > 1 {
-		for _, d := range vals[1:] {
-			dst = e.AppendDuration(append(dst, ','), d, unit, useInt)
+		for _, t := range vals[1:] {
+			dst = strconv.AppendInt(append(dst, ','), t.UnixNano()/div, 10)
+		}
+	}
+	dst = append(dst, ']')
+	return dst
+}
+
+// AppendDuration formats the input duration with the given unit & format
+// and appends the encoded string to the input byte slice.
+func (e Encoder) AppendDuration(dst []byte, d time.Duration, unit time.Duration, useInt bool, precision int) []byte {
+	if useInt {
+		return strconv.AppendInt(dst, int64(d/unit), 10)
+	}
+	return e.AppendFloat64(dst, float64(d)/float64(unit), precision)
+}
+
+// AppendDurations formats the input durations with the given unit & format
+// and appends the encoded string list to the input byte slice.
+func (e Encoder) AppendDurations(dst []byte, vals []time.Duration, unit time.Duration, useInt bool, precision int) []byte {
+	if len(vals) == 0 {
+		return append(dst, '[', ']')
+	}
+	dst = append(dst, '[')
+	dst = e.AppendDuration(dst, vals[0], unit, useInt, precision)
+	if len(vals) > 1 {
+		for _, d := range vals[1:] {
+			dst = e.AppendDuration(append(dst, ','), d, unit, useInt, precision)
 		}
 	}
 	dst = append(dst, ']')

internal/json/types.go

@@ -1,10 +1,10 @@
 package json
 
 import (
-	"encoding/json"
 	"fmt"
 	"math"
 	"net"
+	"reflect"
 	"strconv"
 )
 
@@ -279,7 +279,7 @@ func (Encoder) AppendUints32(dst []byte, vals []uint32) []byte {
 // AppendUint64 converts the input uint64 to a string and
 // appends the encoded string to the input byte slice.
 func (Encoder) AppendUint64(dst []byte, val uint64) []byte {
-	return strconv.AppendUint(dst, uint64(val), 10)
+	return strconv.AppendUint(dst, val, 10)
 }
 
 // AppendUints64 encodes the input uint64s to json and
@@ -299,9 +299,9 @@ func (Encoder) AppendUints64(dst []byte, vals []uint64) []byte {
 	return dst
 }
 
-func appendFloat(dst []byte, val float64, bitSize int) []byte {
+func appendFloat(dst []byte, val float64, bitSize, precision int) []byte {
 	// JSON does not permit NaN or Infinity. A typical JSON encoder would fail
-	// with an error, but a logging library wants the data to get thru so we
+	// with an error, but a logging library wants the data to get through so we
 	// make a tradeoff and store those types as string.
 	switch {
 	case math.IsNaN(val):
@@ -311,26 +311,47 @@ func appendFloat(dst []byte, val float64, bitSize int) []byte {
 	case math.IsInf(val, -1):
 		return append(dst, `"-Inf"`...)
 	}
-	return strconv.AppendFloat(dst, val, 'f', -1, bitSize)
+	// convert as if by es6 number to string conversion
+	// see also https://cs.opensource.google/go/go/+/refs/tags/go1.20.3:src/encoding/json/encode.go;l=573
+	strFmt := byte('f')
+	// If precision is set to a value other than -1, we always just format the float using that precision.
+	if precision == -1 {
+		// Use float32 comparisons for underlying float32 value to get precise cutoffs right.
+		if abs := math.Abs(val); abs != 0 {
+			if bitSize == 64 && (abs < 1e-6 || abs >= 1e21) || bitSize == 32 && (float32(abs) < 1e-6 || float32(abs) >= 1e21) {
+				strFmt = 'e'
+			}
+		}
+	}
+	dst = strconv.AppendFloat(dst, val, strFmt, precision, bitSize)
+	if strFmt == 'e' {
+		// Clean up e-09 to e-9
+		n := len(dst)
+		if n >= 4 && dst[n-4] == 'e' && dst[n-3] == '-' && dst[n-2] == '0' {
+			dst[n-2] = dst[n-1]
+			dst = dst[:n-1]
+		}
+	}
+	return dst
 }
 
 // AppendFloat32 converts the input float32 to a string and
 // appends the encoded string to the input byte slice.
-func (Encoder) AppendFloat32(dst []byte, val float32) []byte {
-	return appendFloat(dst, float64(val), 32)
+func (Encoder) AppendFloat32(dst []byte, val float32, precision int) []byte {
+	return appendFloat(dst, float64(val), 32, precision)
 }
 
 // AppendFloats32 encodes the input float32s to json and
 // appends the encoded string list to the input byte slice.
-func (Encoder) AppendFloats32(dst []byte, vals []float32) []byte {
+func (Encoder) AppendFloats32(dst []byte, vals []float32, precision int) []byte {
 	if len(vals) == 0 {
 		return append(dst, '[', ']')
 	}
 	dst = append(dst, '[')
-	dst = appendFloat(dst, float64(vals[0]), 32)
+	dst = appendFloat(dst, float64(vals[0]), 32, precision)
 	if len(vals) > 1 {
 		for _, val := range vals[1:] {
-			dst = appendFloat(append(dst, ','), float64(val), 32)
+			dst = appendFloat(append(dst, ','), float64(val), 32, precision)
 		}
 	}
 	dst = append(dst, ']')
@@ -339,21 +360,21 @@ func (Encoder) AppendFloats32(dst []byte, vals []float32) []byte {
 
 // AppendFloat64 converts the input float64 to a string and
 // appends the encoded string to the input byte slice.
-func (Encoder) AppendFloat64(dst []byte, val float64) []byte {
-	return appendFloat(dst, val, 64)
+func (Encoder) AppendFloat64(dst []byte, val float64, precision int) []byte {
+	return appendFloat(dst, val, 64, precision)
 }
 
 // AppendFloats64 encodes the input float64s to json and
 // appends the encoded string list to the input byte slice.
-func (Encoder) AppendFloats64(dst []byte, vals []float64) []byte {
+func (Encoder) AppendFloats64(dst []byte, vals []float64, precision int) []byte {
 	if len(vals) == 0 {
 		return append(dst, '[', ']')
 	}
 	dst = append(dst, '[')
-	dst = appendFloat(dst, vals[0], 32)
+	dst = appendFloat(dst, vals[0], 64, precision)
 	if len(vals) > 1 {
 		for _, val := range vals[1:] {
-			dst = appendFloat(append(dst, ','), val, 64)
+			dst = appendFloat(append(dst, ','), val, 64, precision)
 		}
 	}
 	dst = append(dst, ']')
@@ -363,22 +384,34 @@ func (Encoder) AppendFloats64(dst []byte, vals []float64) []byte {
 // AppendInterface marshals the input interface to a string and
 // appends the encoded string to the input byte slice.
 func (e Encoder) AppendInterface(dst []byte, i interface{}) []byte {
-	marshaled, err := json.Marshal(i)
+	marshaled, err := JSONMarshalFunc(i)
 	if err != nil {
 		return e.AppendString(dst, fmt.Sprintf("marshaling error: %v", err))
 	}
 	return append(dst, marshaled...)
 }
 
+// AppendType appends the parameter type (as a string) to the input byte slice.
+func (e Encoder) AppendType(dst []byte, i interface{}) []byte {
+	if i == nil {
+		return e.AppendString(dst, "<nil>")
+	}
+	return e.AppendString(dst, reflect.TypeOf(i).String())
+}
+
 // AppendObjectData takes in an object that is already in a byte array
 // and adds it to the dst.
 func (Encoder) AppendObjectData(dst []byte, o []byte) []byte {
-	// Two conditions we want to put a ',' between existing content and
-	// new content:
-	// 1. new content starts with '{' - which shd be dropped   OR
-	// 2. existing content has already other fields
+	// Three conditions apply here:
+	// 1. new content starts with '{' - which should be dropped   OR
+	// 2. new content starts with '{' - which should be replaced with ','
+	//    to separate with existing content OR
+	// 3. existing content has already other fields
 	if o[0] == '{' {
-		o[0] = ','
+		if len(dst) > 1 {
+			dst = append(dst, ',')
+		}
+		o = o[1:]
 	} else if len(dst) > 1 {
 		dst = append(dst, ',')
 	}

internal/json/types_test.go

@@ -1,7 +1,9 @@
 package json
 
 import (
+	"encoding/json"
 	"math"
+	"math/rand"
 	"net"
 	"reflect"
 	"testing"
@@ -9,18 +11,20 @@ import (
 
 func TestAppendType(t *testing.T) {
 	w := map[string]func(interface{}) []byte{
-		"AppendInt":     func(v interface{}) []byte { return enc.AppendInt([]byte{}, v.(int)) },
-		"AppendInt8":    func(v interface{}) []byte { return enc.AppendInt8([]byte{}, v.(int8)) },
-		"AppendInt16":   func(v interface{}) []byte { return enc.AppendInt16([]byte{}, v.(int16)) },
-		"AppendInt32":   func(v interface{}) []byte { return enc.AppendInt32([]byte{}, v.(int32)) },
-		"AppendInt64":   func(v interface{}) []byte { return enc.AppendInt64([]byte{}, v.(int64)) },
-		"AppendUint":    func(v interface{}) []byte { return enc.AppendUint([]byte{}, v.(uint)) },
-		"AppendUint8":   func(v interface{}) []byte { return enc.AppendUint8([]byte{}, v.(uint8)) },
-		"AppendUint16":  func(v interface{}) []byte { return enc.AppendUint16([]byte{}, v.(uint16)) },
-		"AppendUint32":  func(v interface{}) []byte { return enc.AppendUint32([]byte{}, v.(uint32)) },
-		"AppendUint64":  func(v interface{}) []byte { return enc.AppendUint64([]byte{}, v.(uint64)) },
-		"AppendFloat32": func(v interface{}) []byte { return enc.AppendFloat32([]byte{}, v.(float32)) },
-		"AppendFloat64": func(v interface{}) []byte { return enc.AppendFloat64([]byte{}, v.(float64)) },
+		"AppendInt":                   func(v interface{}) []byte { return enc.AppendInt([]byte{}, v.(int)) },
+		"AppendInt8":                  func(v interface{}) []byte { return enc.AppendInt8([]byte{}, v.(int8)) },
+		"AppendInt16":                 func(v interface{}) []byte { return enc.AppendInt16([]byte{}, v.(int16)) },
+		"AppendInt32":                 func(v interface{}) []byte { return enc.AppendInt32([]byte{}, v.(int32)) },
+		"AppendInt64":                 func(v interface{}) []byte { return enc.AppendInt64([]byte{}, v.(int64)) },
+		"AppendUint":                  func(v interface{}) []byte { return enc.AppendUint([]byte{}, v.(uint)) },
+		"AppendUint8":                 func(v interface{}) []byte { return enc.AppendUint8([]byte{}, v.(uint8)) },
+		"AppendUint16":                func(v interface{}) []byte { return enc.AppendUint16([]byte{}, v.(uint16)) },
+		"AppendUint32":                func(v interface{}) []byte { return enc.AppendUint32([]byte{}, v.(uint32)) },
+		"AppendUint64":                func(v interface{}) []byte { return enc.AppendUint64([]byte{}, v.(uint64)) },
+		"AppendFloat32":               func(v interface{}) []byte { return enc.AppendFloat32([]byte{}, v.(float32), -1) },
+		"AppendFloat64":               func(v interface{}) []byte { return enc.AppendFloat64([]byte{}, v.(float64), -1) },
+		"AppendFloat32SmallPrecision": func(v interface{}) []byte { return enc.AppendFloat32([]byte{}, v.(float32), 1) },
+		"AppendFloat64SmallPrecision": func(v interface{}) []byte { return enc.AppendFloat64([]byte{}, v.(float64), 1) },
 	}
 	tests := []struct {
 		name  string
@@ -44,7 +48,7 @@ func TestAppendType(t *testing.T) {
 		{"AppendFloat32(0)", "AppendFloat32", float32(0), []byte(`0`)},
 		{"AppendFloat32(-1.1)", "AppendFloat32", float32(-1.1), []byte(`-1.1`)},
 		{"AppendFloat32(1e20)", "AppendFloat32", float32(1e20), []byte(`100000000000000000000`)},
-		{"AppendFloat32(1e21)", "AppendFloat32", float32(1e21), []byte(`1000000000000000000000`)},
+		{"AppendFloat32(1e21)", "AppendFloat32", float32(1e21), []byte(`1e+21`)},
 
 		{"AppendFloat64(-Inf)", "AppendFloat64", float64(math.Inf(-1)), []byte(`"-Inf"`)},
 		{"AppendFloat64(+Inf)", "AppendFloat64", float64(math.Inf(1)), []byte(`"+Inf"`)},
@@ -52,7 +56,10 @@ func TestAppendType(t *testing.T) {
 		{"AppendFloat64(0)", "AppendFloat64", float64(0), []byte(`0`)},
 		{"AppendFloat64(-1.1)", "AppendFloat64", float64(-1.1), []byte(`-1.1`)},
 		{"AppendFloat64(1e20)", "AppendFloat64", float64(1e20), []byte(`100000000000000000000`)},
-		{"AppendFloat64(1e21)", "AppendFloat64", float64(1e21), []byte(`1000000000000000000000`)},
+		{"AppendFloat64(1e21)", "AppendFloat64", float64(1e21), []byte(`1e+21`)},
+
+		{"AppendFloat32SmallPrecision(-1.123)", "AppendFloat32SmallPrecision", float32(-1.123), []byte(`-1.1`)},
+		{"AppendFloat64SmallPrecision(-1.123)", "AppendFloat64SmallPrecision", float64(-1.123), []byte(`-1.1`)},
 	}
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
@@ -165,3 +172,382 @@ func Test_appendMac(t *testing.T) {
 		})
 	}
 }
+
+func Test_appendType(t *testing.T) {
+	typeTests := []struct {
+		label string
+		input interface{}
+		want  []byte
+	}{
+		{"int", 42, []byte(`"int"`)},
+		{"MAC", net.HardwareAddr{0x12, 0x34, 0x00, 0x00, 0x90, 0xab}, []byte(`"net.HardwareAddr"`)},
+		{"float64", float64(2.50), []byte(`"float64"`)},
+		{"nil", nil, []byte(`"<nil>"`)},
+		{"bool", true, []byte(`"bool"`)},
+	}
+
+	for _, tt := range typeTests {
+		t.Run(tt.label, func(t *testing.T) {
+			if got := enc.AppendType([]byte{}, tt.input); !reflect.DeepEqual(got, tt.want) {
+				t.Errorf("appendType() = %s, want %s", got, tt.want)
+			}
+		})
+	}
+}
+
+func Test_appendObjectData(t *testing.T) {
+	tests := []struct {
+		dst  []byte
+		obj  []byte
+		want []byte
+	}{
+		{[]byte{}, []byte(`{"foo":"bar"}`), []byte(`"foo":"bar"}`)},
+		{[]byte(`{"qux":"quz"`), []byte(`{"foo":"bar"}`), []byte(`{"qux":"quz","foo":"bar"}`)},
+		{[]byte{}, []byte(`"foo":"bar"`), []byte(`"foo":"bar"`)},
+		{[]byte(`{"qux":"quz"`), []byte(`"foo":"bar"`), []byte(`{"qux":"quz","foo":"bar"`)},
+	}
+	for _, tt := range tests {
+		t.Run("ObjectData", func(t *testing.T) {
+			if got := enc.AppendObjectData(tt.dst, tt.obj); !reflect.DeepEqual(got, tt.want) {
+				t.Errorf("appendObjectData() = %s, want %s", got, tt.want)
+			}
+		})
+	}
+}
+
+var float64Tests = []struct {
+	Name string
+	Val  float64
+	Want string
+}{
+	{
+		Name: "Positive integer",
+		Val:  1234.0,
+		Want: "1234",
+	},
+	{
+		Name: "Negative integer",
+		Val:  -5678.0,
+		Want: "-5678",
+	},
+	{
+		Name: "Positive decimal",
+		Val:  12.3456,
+		Want: "12.3456",
+	},
+	{
+		Name: "Negative decimal",
+		Val:  -78.9012,
+		Want: "-78.9012",
+	},
+	{
+		Name: "Large positive number",
+		Val:  123456789.0,
+		Want: "123456789",
+	},
+	{
+		Name: "Large negative number",
+		Val:  -987654321.0,
+		Want: "-987654321",
+	},
+	{
+		Name: "Zero",
+		Val:  0.0,
+		Want: "0",
+	},
+	{
+		Name: "Smallest positive value",
+		Val:  math.SmallestNonzeroFloat64,
+		Want: "5e-324",
+	},
+	{
+		Name: "Largest positive value",
+		Val:  math.MaxFloat64,
+		Want: "1.7976931348623157e+308",
+	},
+	{
+		Name: "Smallest negative value",
+		Val:  -math.SmallestNonzeroFloat64,
+		Want: "-5e-324",
+	},
+	{
+		Name: "Largest negative value",
+		Val:  -math.MaxFloat64,
+		Want: "-1.7976931348623157e+308",
+	},
+	{
+		Name: "NaN",
+		Val:  math.NaN(),
+		Want: `"NaN"`,
+	},
+	{
+		Name: "+Inf",
+		Val:  math.Inf(1),
+		Want: `"+Inf"`,
+	},
+	{
+		Name: "-Inf",
+		Val:  math.Inf(-1),
+		Want: `"-Inf"`,
+	},
+	{
+		Name: "Clean up e-09 to e-9 case 1",
+		Val:  1e-9,
+		Want: "1e-9",
+	},
+	{
+		Name: "Clean up e-09 to e-9 case 2",
+		Val:  -2.236734e-9,
+		Want: "-2.236734e-9",
+	},
+}
+
+func TestEncoder_AppendFloat64(t *testing.T) {
+	for _, tc := range float64Tests {
+		t.Run(tc.Name, func(t *testing.T) {
+			var b []byte
+			b = (Encoder{}).AppendFloat64(b, tc.Val, -1)
+			if s := string(b); tc.Want != s {
+				t.Errorf("%q", s)
+			}
+		})
+	}
+}
+
+func FuzzEncoder_AppendFloat64(f *testing.F) {
+	for _, tc := range float64Tests {
+		f.Add(tc.Val)
+	}
+	f.Fuzz(func(t *testing.T, val float64) {
+		actual := (Encoder{}).AppendFloat64(nil, val, -1)
+		if len(actual) == 0 {
+			t.Fatal("empty buffer")
+		}
+
+		if actual[0] == '"' {
+			switch string(actual) {
+			case `"NaN"`:
+				if !math.IsNaN(val) {
+					t.Fatalf("expected %v got NaN", val)
+				}
+			case `"+Inf"`:
+				if !math.IsInf(val, 1) {
+					t.Fatalf("expected %v got +Inf", val)
+				}
+			case `"-Inf"`:
+				if !math.IsInf(val, -1) {
+					t.Fatalf("expected %v got -Inf", val)
+				}
+			default:
+				t.Fatalf("unexpected string: %s", actual)
+			}
+			return
+		}
+
+		if expected, err := json.Marshal(val); err != nil {
+			t.Error(err)
+		} else if string(actual) != string(expected) {
+			t.Errorf("expected %s, got %s", expected, actual)
+		}
+
+		var parsed float64
+		if err := json.Unmarshal(actual, &parsed); err != nil {
+			t.Fatal(err)
+		}
+
+		if parsed != val {
+			t.Fatalf("expected %v, got %v", val, parsed)
+		}
+	})
+}
+
+var float32Tests = []struct {
+	Name string
+	Val  float32
+	Want string
+}{
+	{
+		Name: "Positive integer",
+		Val:  1234.0,
+		Want: "1234",
+	},
+	{
+		Name: "Negative integer",
+		Val:  -5678.0,
+		Want: "-5678",
+	},
+	{
+		Name: "Positive decimal",
+		Val:  12.3456,
+		Want: "12.3456",
+	},
+	{
+		Name: "Negative decimal",
+		Val:  -78.9012,
+		Want: "-78.9012",
+	},
+	{
+		Name: "Large positive number",
+		Val:  123456789.0,
+		Want: "123456790",
+	},
+	{
+		Name: "Large negative number",
+		Val:  -987654321.0,
+		Want: "-987654340",
+	},
+	{
+		Name: "Zero",
+		Val:  0.0,
+		Want: "0",
+	},
+	{
+		Name: "Smallest positive value",
+		Val:  math.SmallestNonzeroFloat32,
+		Want: "1e-45",
+	},
+	{
+		Name: "Largest positive value",
+		Val:  math.MaxFloat32,
+		Want: "3.4028235e+38",
+	},
+	{
+		Name: "Smallest negative value",
+		Val:  -math.SmallestNonzeroFloat32,
+		Want: "-1e-45",
+	},
+	{
+		Name: "Largest negative value",
+		Val:  -math.MaxFloat32,
+		Want: "-3.4028235e+38",
+	},
+	{
+		Name: "NaN",
+		Val:  float32(math.NaN()),
+		Want: `"NaN"`,
+	},
+	{
+		Name: "+Inf",
+		Val:  float32(math.Inf(1)),
+		Want: `"+Inf"`,
+	},
+	{
+		Name: "-Inf",
+		Val:  float32(math.Inf(-1)),
+		Want: `"-Inf"`,
+	},
+	{
+		Name: "Clean up e-09 to e-9 case 1",
+		Val:  1e-9,
+		Want: "1e-9",
+	},
+	{
+		Name: "Clean up e-09 to e-9 case 2",
+		Val:  -2.236734e-9,
+		Want: "-2.236734e-9",
+	},
+}
+
+func TestEncoder_AppendFloat32(t *testing.T) {
+	for _, tc := range float32Tests {
+		t.Run(tc.Name, func(t *testing.T) {
+			var b []byte
+			b = (Encoder{}).AppendFloat32(b, tc.Val, -1)
+			if s := string(b); tc.Want != s {
+				t.Errorf("%q", s)
+			}
+		})
+	}
+}
+
+func FuzzEncoder_AppendFloat32(f *testing.F) {
+	for _, tc := range float32Tests {
+		f.Add(tc.Val)
+	}
+	f.Fuzz(func(t *testing.T, val float32) {
+		actual := (Encoder{}).AppendFloat32(nil, val, -1)
+		if len(actual) == 0 {
+			t.Fatal("empty buffer")
+		}
+
+		if actual[0] == '"' {
+			val := float64(val)
+			switch string(actual) {
+			case `"NaN"`:
+				if !math.IsNaN(val) {
+					t.Fatalf("expected %v got NaN", val)
+				}
+			case `"+Inf"`:
+				if !math.IsInf(val, 1) {
+					t.Fatalf("expected %v got +Inf", val)
+				}
+			case `"-Inf"`:
+				if !math.IsInf(val, -1) {
+					t.Fatalf("expected %v got -Inf", val)
+				}
+			default:
+				t.Fatalf("unexpected string: %s", actual)
+			}
+			return
+		}
+
+		if expected, err := json.Marshal(val); err != nil {
+			t.Error(err)
+		} else if string(actual) != string(expected) {
+			t.Errorf("expected %s, got %s", expected, actual)
+		}
+
+		var parsed float32
+		if err := json.Unmarshal(actual, &parsed); err != nil {
+			t.Fatal(err)
+		}
+
+		if parsed != val {
+			t.Fatalf("expected %v, got %v", val, parsed)
+		}
+	})
+}
+
+func generateFloat32s(n int) []float32 {
+	floats := make([]float32, n)
+	for i := 0; i < n; i++ {
+		floats[i] = rand.Float32()
+	}
+	return floats
+}
+
+func generateFloat64s(n int) []float64 {
+	floats := make([]float64, n)
+	for i := 0; i < n; i++ {
+		floats[i] = rand.Float64()
+	}
+	return floats
+}
+
+// this is really just for the memory allocation characteristics
+func BenchmarkEncoder_AppendFloat32(b *testing.B) {
+	floats := append(generateFloat32s(5000), float32(math.NaN()), float32(math.Inf(1)), float32(math.Inf(-1)))
+	dst := make([]byte, 0, 128)
+
+	b.ResetTimer()
+
+	for i := 0; i < b.N; i++ {
+		for _, f := range floats {
+			dst = (Encoder{}).AppendFloat32(dst[:0], f, -1)
+		}
+	}
+}
+
+// this is really just for the memory allocation characteristics
+func BenchmarkEncoder_AppendFloat64(b *testing.B) {
+	floats := append(generateFloat64s(5000), math.NaN(), math.Inf(1), math.Inf(-1))
+	dst := make([]byte, 0, 128)
+
+	b.ResetTimer()
+
+	for i := 0; i < b.N; i++ {
+		for _, f := range floats {
+			dst = (Encoder{}).AppendFloat64(dst[:0], f, -1)
+		}
+	}
+}

journald/journald.go

@@ -1,3 +1,4 @@
+//go:build !windows
 // +build !windows
 
 // Package journald provides a io.Writer to send the logs
@@ -20,11 +21,12 @@ import (
 	"bytes"
 	"encoding/json"
 	"fmt"
-	"github.com/coreos/go-systemd/journal"
-	"github.com/rs/zerolog"
-	"github.com/rs/zerolog/internal/cbor"
 	"io"
 	"strings"
+
+	"github.com/coreos/go-systemd/v22/journal"
+	"github.com/rs/zerolog"
+	"github.com/rs/zerolog/internal/cbor"
 )
 
 const defaultJournalDPrio = journal.PriNotice
@@ -47,6 +49,8 @@ func levelToJPrio(zLevel string) journal.Priority {
 	lvl, _ := zerolog.ParseLevel(zLevel)
 
 	switch lvl {
+	case zerolog.TraceLevel:
+		return journal.PriDebug
 	case zerolog.DebugLevel:
 		return journal.PriDebug
 	case zerolog.InfoLevel:
@@ -66,17 +70,14 @@ func levelToJPrio(zLevel string) journal.Priority {
 }
 
 func (w journalWriter) Write(p []byte) (n int, err error) {
-	if !journal.Enabled() {
-		err = fmt.Errorf("Cannot connect to journalD!!")
-		return
-	}
 	var event map[string]interface{}
+	origPLen := len(p)
 	p = cbor.DecodeIfBinaryToBytes(p)
 	d := json.NewDecoder(bytes.NewReader(p))
 	d.UseNumber()
 	err = d.Decode(&event)
 	jPrio := defaultJournalDPrio
-	args := make(map[string]string, 0)
+	args := make(map[string]string)
 	if err != nil {
 		return
 	}
@@ -95,13 +96,13 @@ func (w journalWriter) Write(p []byte) (n int, err error) {
 			continue
 		}
 
-		switch value.(type) {
+		switch v := value.(type) {
 		case string:
-			args[jKey], _ = value.(string)
+			args[jKey] = v
 		case json.Number:
 			args[jKey] = fmt.Sprint(value)
 		default:
-			b, err := json.Marshal(value)
+			b, err := zerolog.InterfaceMarshalFunc(value)
 			if err != nil {
 				args[jKey] = fmt.Sprintf("[error: %v]", err)
 			} else {
@@ -111,5 +112,10 @@ func (w journalWriter) Write(p []byte) (n int, err error) {
 	}
 	args["JSON"] = string(p)
 	err = journal.Send(msg, jPrio, args)
+
+	if err == nil {
+		n = origPLen
+	}
+
 	return
 }

journald/journald_test.go

@@ -1,9 +1,15 @@
-// +build !windows
+// +build linux
 
 package journald_test
 
-import "github.com/rs/zerolog"
-import "github.com/rs/zerolog/journald"
+import (
+	"bytes"
+	"io"
+	"testing"
+
+	"github.com/rs/zerolog"
+	"github.com/rs/zerolog/journald"
+)
 
 func ExampleNewJournalDWriter() {
 	log := zerolog.New(journald.NewJournalDWriter())
@@ -42,3 +48,39 @@ Thu 2018-04-26 22:30:20.768136 PDT [s=3284d695bde946e4b5017c77a399237f;i=329f0;b
     _PID=27103
     _SOURCE_REALTIME_TIMESTAMP=1524807020768136
 */
+
+func TestWriteReturnsNoOfWrittenBytes(t *testing.T) {
+	input := []byte(`{"level":"info","time":1570912626,"message":"Starting..."}`)
+	wr := journald.NewJournalDWriter()
+	want := len(input)
+	got, err := wr.Write(input)
+
+	if err != nil {
+		t.Errorf("Unexpected error %v", err)
+	}
+
+	if want != got {
+		t.Errorf("Expected %d bytes to be written got %d", want, got)
+	}
+}
+
+func TestMultiWrite(t *testing.T) {
+	var (
+		w1 = new(bytes.Buffer)
+		w2 = new(bytes.Buffer)
+		w3 = journald.NewJournalDWriter()
+	)
+
+	zerolog.ErrorHandler = func(err error) {
+		if err == io.ErrShortWrite {
+			t.Errorf("Unexpected ShortWriteError")
+			t.FailNow()
+		}
+	}
+
+	log := zerolog.New(io.MultiWriter(w1, w2, w3)).With().Logger()
+
+	for i := 0; i < 10; i++ {
+		log.Info().Msg("Tick!")
+	}
+}

log.go

@@ -24,7 +24,7 @@
 //
 // Sub-loggers let you chain loggers with additional context:
 //
-//     sublogger := log.With().Str("component": "foo").Logger()
+//     sublogger := log.With().Str("component", "foo").Logger()
 //     sublogger.Info().Msg("hello world")
 //     // Output: {"time":1494567715,"level":"info","message":"hello world","component":"foo"}
 //
@@ -82,8 +82,9 @@
 //     log.Warn().Msg("")
 //     // Output: {"level":"warn","severity":"warn"}
 //
+// # Caveats
 //
-// Caveats
+// Field duplication:
 //
 // There is no fields deduplication out-of-the-box.
 // Using the same key multiple times creates new key in final JSON each time.
@@ -94,20 +95,36 @@
 //            Msg("dup")
 //     // Output: {"level":"info","time":1494567715,"time":1494567715,"message":"dup"}
 //
-// However, it’s not a big deal though as JSON accepts dup keys,
-// the last one prevails.
+// In this case, many consumers will take the last value,
+// but this is not guaranteed; check yours if in doubt.
+//
+// Concurrency safety:
+//
+// Be careful when calling UpdateContext. It is not concurrency safe. Use the With method to create a child logger:
+//
+//     func handler(w http.ResponseWriter, r *http.Request) {
+//         // Create a child logger for concurrency safety
+//         logger := log.Logger.With().Logger()
+//
+//         // Add context fields, for example User-Agent from HTTP headers
+//         logger.UpdateContext(func(c zerolog.Context) zerolog.Context {
+//             ...
+//         })
+//     }
 package zerolog
 
 import (
+	"context"
+	"errors"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"os"
 	"strconv"
+	"strings"
 )
 
 // Level defines log levels.
-type Level uint8
+type Level int8
 
 const (
 	// DebugLevel defines debug log level.
@@ -126,53 +143,87 @@ const (
 	NoLevel
 	// Disabled disables the logger.
 	Disabled
+
+	// TraceLevel defines trace log level.
+	TraceLevel Level = -1
+	// Values less than TraceLevel are handled as numbers.
 )
 
 func (l Level) String() string {
 	switch l {
+	case TraceLevel:
+		return LevelTraceValue
 	case DebugLevel:
-		return "debug"
+		return LevelDebugValue
 	case InfoLevel:
-		return "info"
+		return LevelInfoValue
 	case WarnLevel:
-		return "warn"
+		return LevelWarnValue
 	case ErrorLevel:
-		return "error"
+		return LevelErrorValue
 	case FatalLevel:
-		return "fatal"
+		return LevelFatalValue
 	case PanicLevel:
-		return "panic"
+		return LevelPanicValue
+	case Disabled:
+		return "disabled"
 	case NoLevel:
 		return ""
 	}
-	return ""
+	return strconv.Itoa(int(l))
 }
 
 // ParseLevel converts a level string into a zerolog Level value.
 // returns an error if the input string does not match known values.
 func ParseLevel(levelStr string) (Level, error) {
-	switch levelStr {
-	case DebugLevel.String():
+	switch {
+	case strings.EqualFold(levelStr, LevelFieldMarshalFunc(TraceLevel)):
+		return TraceLevel, nil
+	case strings.EqualFold(levelStr, LevelFieldMarshalFunc(DebugLevel)):
 		return DebugLevel, nil
-	case InfoLevel.String():
+	case strings.EqualFold(levelStr, LevelFieldMarshalFunc(InfoLevel)):
 		return InfoLevel, nil
-	case WarnLevel.String():
+	case strings.EqualFold(levelStr, LevelFieldMarshalFunc(WarnLevel)):
 		return WarnLevel, nil
-	case ErrorLevel.String():
+	case strings.EqualFold(levelStr, LevelFieldMarshalFunc(ErrorLevel)):
 		return ErrorLevel, nil
-	case FatalLevel.String():
+	case strings.EqualFold(levelStr, LevelFieldMarshalFunc(FatalLevel)):
 		return FatalLevel, nil
-	case PanicLevel.String():
+	case strings.EqualFold(levelStr, LevelFieldMarshalFunc(PanicLevel)):
 		return PanicLevel, nil
-	case NoLevel.String():
+	case strings.EqualFold(levelStr, LevelFieldMarshalFunc(Disabled)):
+		return Disabled, nil
+	case strings.EqualFold(levelStr, LevelFieldMarshalFunc(NoLevel)):
 		return NoLevel, nil
 	}
-	return NoLevel, fmt.Errorf("Unknown Level String: '%s', defaulting to NoLevel", levelStr)
+	i, err := strconv.Atoi(levelStr)
+	if err != nil {
+		return NoLevel, fmt.Errorf("Unknown Level String: '%s', defaulting to NoLevel", levelStr)
+	}
+	if i > 127 || i < -128 {
+		return NoLevel, fmt.Errorf("Out-Of-Bounds Level: '%d', defaulting to NoLevel", i)
+	}
+	return Level(i), nil
+}
+
+// UnmarshalText implements encoding.TextUnmarshaler to allow for easy reading from toml/yaml/json formats
+func (l *Level) UnmarshalText(text []byte) error {
+	if l == nil {
+		return errors.New("can't unmarshal a nil *Level")
+	}
+	var err error
+	*l, err = ParseLevel(string(text))
+	return err
+}
+
+// MarshalText implements encoding.TextMarshaler to allow for easy writing into toml/yaml/json formats
+func (l Level) MarshalText() ([]byte, error) {
+	return []byte(LevelFieldMarshalFunc(l)), nil
 }
 
 // A Logger represents an active logging object that generates lines
 // of JSON output to an io.Writer. Each logging operation makes a single
-// call to the Writer's Write method. There is no guaranty on access
+// call to the Writer's Write method. There is no guarantee on access
 // serialization to the Writer. If your Writer is not thread safe,
 // you may consider a sync wrapper.
 type Logger struct {
@@ -181,6 +232,8 @@ type Logger struct {
 	sampler Sampler
 	context []byte
 	hooks   []Hook
+	stack   bool
+	ctx     context.Context
 }
 
 // New creates a root logger with given output writer. If the output writer implements
@@ -188,17 +241,17 @@ type Logger struct {
 // one.
 //
 // Each logging operation makes a single call to the Writer's Write method. There is no
-// guaranty on access serialization to the Writer. If your Writer is not thread safe,
+// guarantee on access serialization to the Writer. If your Writer is not thread safe,
 // you may consider using sync wrapper.
 func New(w io.Writer) Logger {
 	if w == nil {
-		w = ioutil.Discard
+		w = io.Discard
 	}
 	lw, ok := w.(LevelWriter)
 	if !ok {
-		lw = levelWriterAdapter{w}
+		lw = LevelWriterAdapter{w}
 	}
-	return Logger{w: lw}
+	return Logger{w: lw, level: TraceLevel}
 }
 
 // Nop returns a disabled logger for which all operation are no-op.
@@ -211,6 +264,7 @@ func (l Logger) Output(w io.Writer) Logger {
 	l2 := New(w)
 	l2.level = l.level
 	l2.sampler = l.sampler
+	l2.stack = l.stack
 	if len(l.hooks) > 0 {
 		l2.hooks = append(l2.hooks, l.hooks...)
 	}
@@ -227,13 +281,18 @@ func (l Logger) With() Context {
 	l.context = make([]byte, 0, 500)
 	if context != nil {
 		l.context = append(l.context, context...)
+	} else {
+		// This is needed for AppendKey to not check len of input
+		// thus making it inlinable
+		l.context = enc.AppendBeginMarker(l.context)
 	}
 	return Context{l}
 }
 
 // UpdateContext updates the internal logger's context.
 //
-// Use this method with caution. If unsure, prefer the With method.
+// Caution: This method is not concurrency safe.
+// Use the With method to create a child logger before modifying the context from concurrent goroutines.
 func (l *Logger) UpdateContext(update func(c Context) Context) {
 	if l == disabledLogger {
 		return
@@ -241,6 +300,9 @@ func (l *Logger) UpdateContext(update func(c Context) Context) {
 	if cap(l.context) == 0 {
 		l.context = make([]byte, 0, 500)
 	}
+	if len(l.context) == 0 {
+		l.context = enc.AppendBeginMarker(l.context)
+	}
 	c := update(Context{*l})
 	l.context = c.l.context
 }
@@ -251,6 +313,11 @@ func (l Logger) Level(lvl Level) Logger {
 	return l
 }
 
+// GetLevel returns the current Level of l.
+func (l Logger) GetLevel() Level {
+	return l.level
+}
+
 // Sample returns a logger with the s sampler.
 func (l Logger) Sample(s Sampler) Logger {
 	l.sampler = s
@@ -258,11 +325,23 @@ func (l Logger) Sample(s Sampler) Logger {
 }
 
 // Hook returns a logger with the h Hook.
-func (l Logger) Hook(h Hook) Logger {
-	l.hooks = append(l.hooks, h)
+func (l Logger) Hook(hooks ...Hook) Logger {
+	if len(hooks) == 0 {
+		return l
+	}
+	newHooks := make([]Hook, len(l.hooks), len(l.hooks)+len(hooks))
+	copy(newHooks, l.hooks)
+	l.hooks = append(newHooks, hooks...)
 	return l
 }
 
+// Trace starts a new message with trace level.
+//
+// You must call Msg on the returned event in order to send the event.
+func (l *Logger) Trace() *Event {
+	return l.newEvent(TraceLevel, nil)
+}
+
 // Debug starts a new message with debug level.
 //
 // You must call Msg on the returned event in order to send the event.
@@ -291,12 +370,31 @@ func (l *Logger) Error() *Event {
 	return l.newEvent(ErrorLevel, nil)
 }
 
+// Err starts a new message with error level with err as a field if not nil or
+// with info level if err is nil.
+//
+// You must call Msg on the returned event in order to send the event.
+func (l *Logger) Err(err error) *Event {
+	if err != nil {
+		return l.Error().Err(err)
+	}
+
+	return l.Info()
+}
+
 // Fatal starts a new message with fatal level. The os.Exit(1) function
 // is called by the Msg method, which terminates the program immediately.
 //
 // You must call Msg on the returned event in order to send the event.
 func (l *Logger) Fatal() *Event {
-	return l.newEvent(FatalLevel, func(msg string) { os.Exit(1) })
+	return l.newEvent(FatalLevel, func(msg string) {
+		if closer, ok := l.w.(io.Closer); ok {
+			// Close the writer to flush any buffered message. Otherwise the message
+			// will be lost as os.Exit() terminates the program immediately.
+			closer.Close()
+		}
+		os.Exit(1)
+	})
 }
 
 // Panic starts a new message with panic level. The panic() function
@@ -309,11 +407,13 @@ func (l *Logger) Panic() *Event {
 
 // WithLevel starts a new message with level. Unlike Fatal and Panic
 // methods, WithLevel does not terminate the program or stop the ordinary
-// flow of a gourotine when used with their respective levels.
+// flow of a goroutine when used with their respective levels.
 //
 // You must call Msg on the returned event in order to send the event.
 func (l *Logger) WithLevel(level Level) *Event {
 	switch level {
+	case TraceLevel:
+		return l.Trace()
 	case DebugLevel:
 		return l.Debug()
 	case InfoLevel:
@@ -331,7 +431,7 @@ func (l *Logger) WithLevel(level Level) *Event {
 	case Disabled:
 		return nil
 	default:
-		panic("zerolog: WithLevel(): invalid level: " + strconv.Itoa(int(level)))
+		return l.newEvent(level, nil)
 	}
 }
 
@@ -347,7 +447,7 @@ func (l *Logger) Log() *Event {
 // Arguments are handled in the manner of fmt.Print.
 func (l *Logger) Print(v ...interface{}) {
 	if e := l.Debug(); e.Enabled() {
-		e.Msg(fmt.Sprint(v...))
+		e.CallerSkipFrame(1).Msg(fmt.Sprint(v...))
 	}
 }
 
@@ -355,7 +455,15 @@ func (l *Logger) Print(v ...interface{}) {
 // Arguments are handled in the manner of fmt.Printf.
 func (l *Logger) Printf(format string, v ...interface{}) {
 	if e := l.Debug(); e.Enabled() {
-		e.Msg(fmt.Sprintf(format, v...))
+		e.CallerSkipFrame(1).Msg(fmt.Sprintf(format, v...))
+	}
+}
+
+// Println sends a log event using debug level and no extra field.
+// Arguments are handled in the manner of fmt.Println.
+func (l *Logger) Println(v ...interface{}) {
+	if e := l.Debug(); e.Enabled() {
+		e.CallerSkipFrame(1).Msg(fmt.Sprintln(v...))
 	}
 }
 
@@ -367,29 +475,39 @@ func (l Logger) Write(p []byte) (n int, err error) {
 		// Trim CR added by stdlog.
 		p = p[0 : n-1]
 	}
-	l.Log().Msg(string(p))
+	l.Log().CallerSkipFrame(1).Msg(string(p))
 	return
 }
 
 func (l *Logger) newEvent(level Level, done func(string)) *Event {
 	enabled := l.should(level)
 	if !enabled {
+		if done != nil {
+			done("")
+		}
 		return nil
 	}
 	e := newEvent(l.w, level)
 	e.done = done
 	e.ch = l.hooks
-	if level != NoLevel {
-		e.Str(LevelFieldName, level.String())
+	e.ctx = l.ctx
+	if level != NoLevel && LevelFieldName != "" {
+		e.Str(LevelFieldName, LevelFieldMarshalFunc(level))
 	}
-	if l.context != nil && len(l.context) > 0 {
+	if l.context != nil && len(l.context) > 1 {
 		e.buf = enc.AppendObjectData(e.buf, l.context)
 	}
+	if l.stack {
+		e.Stack()
+	}
 	return e
 }
 
 // should returns true if the log event should be logged.
 func (l *Logger) should(lvl Level) bool {
+	if l.w == nil {
+		return false
+	}
 	if lvl < l.level || lvl < GlobalLevel() {
 		return false
 	}

log/log.go

@@ -3,6 +3,7 @@ package log
 
 import (
 	"context"
+	"fmt"
 	"io"
 	"os"
 
@@ -37,6 +38,21 @@ func Hook(h zerolog.Hook) zerolog.Logger {
 	return Logger.Hook(h)
 }
 
+// Err starts a new message with error level with err as a field if not nil or
+// with info level if err is nil.
+//
+// You must call Msg on the returned event in order to send the event.
+func Err(err error) *zerolog.Event {
+	return Logger.Err(err)
+}
+
+// Trace starts a new message with trace level.
+//
+// You must call Msg on the returned event in order to send the event.
+func Trace() *zerolog.Event {
+	return Logger.Trace()
+}
+
 // Debug starts a new message with debug level.
 //
 // You must call Msg on the returned event in order to send the event.
@@ -99,13 +115,13 @@ func Log() *zerolog.Event {
 // Print sends a log event using debug level and no extra field.
 // Arguments are handled in the manner of fmt.Print.
 func Print(v ...interface{}) {
-	Logger.Print(v...)
+	Logger.Debug().CallerSkipFrame(1).Msg(fmt.Sprint(v...))
 }
 
 // Printf sends a log event using debug level and no extra field.
 // Arguments are handled in the manner of fmt.Printf.
 func Printf(format string, v ...interface{}) {
-	Logger.Printf(format, v...)
+	Logger.Debug().CallerSkipFrame(1).Msgf(format, v...)
 }
 
 // Ctx returns the Logger associated with the ctx. If no logger

log/log_example_test.go

@@ -54,6 +54,25 @@ func ExampleLog() {
 	// Output: {"time":1199811905,"message":"hello world"}
 }
 
+// Example of a conditional level based on the presence of an error.
+func ExampleErr() {
+	setup()
+	err := errors.New("some error")
+	log.Err(err).Msg("hello world")
+	log.Err(nil).Msg("hello world")
+
+	// Output: {"level":"error","error":"some error","time":1199811905,"message":"hello world"}
+	// {"level":"info","time":1199811905,"message":"hello world"}
+}
+
+// Example of a log at a particular "level" (in this case, "trace")
+func ExampleTrace() {
+	setup()
+	log.Trace().Msg("hello world")
+
+	// Output: {"level":"trace","time":1199811905,"message":"hello world"}
+}
+
 // Example of a log at a particular "level" (in this case, "debug")
 func ExampleDebug() {
 	setup()

log_example_test.go

@@ -72,7 +72,7 @@ func ExampleLogger_Hook() {
 	var levelNameHook LevelNameHook
 	var messageHook MessageHook = "The message"
 
-	log := zerolog.New(os.Stdout).Hook(levelNameHook).Hook(messageHook)
+	log := zerolog.New(os.Stdout).Hook(levelNameHook, messageHook)
 
 	log.Info().Msg("hello world")
 
@@ -95,6 +95,25 @@ func ExampleLogger_Printf() {
 	// Output: {"level":"debug","message":"hello world"}
 }
 
+func ExampleLogger_Println() {
+	log := zerolog.New(os.Stdout)
+
+	log.Println("hello world")
+
+	// Output: {"level":"debug","message":"hello world\n"}
+}
+
+func ExampleLogger_Trace() {
+	log := zerolog.New(os.Stdout)
+
+	log.Trace().
+		Str("foo", "bar").
+		Int("n", 123).
+		Msg("hello world")
+
+	// Output: {"level":"trace","foo":"bar","n":123,"message":"hello world"}
+}
+
 func ExampleLogger_Debug() {
 	log := zerolog.New(os.Stdout)
 
@@ -227,11 +246,15 @@ func ExampleEvent_Array() {
 		Str("foo", "bar").
 		Array("array", zerolog.Arr().
 			Str("baz").
-			Int(1),
+			Int(1).
+			Dict(zerolog.Dict().
+				Str("bar", "baz").
+				Int("n", 1),
+			),
 		).
 		Msg("hello world")
 
-	// Output: {"foo":"bar","array":["baz",1],"message":"hello world"}
+	// Output: {"foo":"bar","array":["baz",1,{"bar":"baz","n":1}],"message":"hello world"}
 }
 
 func ExampleEvent_Array_object() {
@@ -296,7 +319,7 @@ func ExampleEvent_Interface() {
 }
 
 func ExampleEvent_Dur() {
-	d := time.Duration(10 * time.Second)
+	d := 10 * time.Second
 
 	log := zerolog.New(os.Stdout)
 
@@ -310,8 +333,8 @@ func ExampleEvent_Dur() {
 
 func ExampleEvent_Durs() {
 	d := []time.Duration{
-		time.Duration(10 * time.Second),
-		time.Duration(20 * time.Second),
+		10 * time.Second,
+		20 * time.Second,
 	}
 
 	log := zerolog.New(os.Stdout)
@@ -324,6 +347,38 @@ func ExampleEvent_Durs() {
 	// Output: {"foo":"bar","durs":[10000,20000],"message":"hello world"}
 }
 
+func ExampleEvent_Fields_map() {
+	fields := map[string]interface{}{
+		"bar": "baz",
+		"n":   1,
+	}
+
+	log := zerolog.New(os.Stdout)
+
+	log.Log().
+		Str("foo", "bar").
+		Fields(fields).
+		Msg("hello world")
+
+	// Output: {"foo":"bar","bar":"baz","n":1,"message":"hello world"}
+}
+
+func ExampleEvent_Fields_slice() {
+	fields := []interface{}{
+		"bar", "baz",
+		"n", 1,
+	}
+
+	log := zerolog.New(os.Stdout)
+
+	log.Log().
+		Str("foo", "bar").
+		Fields(fields).
+		Msg("hello world")
+
+	// Output: {"foo":"bar","bar":"baz","n":1,"message":"hello world"}
+}
+
 func ExampleContext_Dict() {
 	log := zerolog.New(os.Stdout).With().
 		Str("foo", "bar").
@@ -413,7 +468,7 @@ func ExampleContext_Interface() {
 }
 
 func ExampleContext_Dur() {
-	d := time.Duration(10 * time.Second)
+	d := 10 * time.Second
 
 	log := zerolog.New(os.Stdout).With().
 		Str("foo", "bar").
@@ -427,8 +482,8 @@ func ExampleContext_Dur() {
 
 func ExampleContext_Durs() {
 	d := []time.Duration{
-		time.Duration(10 * time.Second),
-		time.Duration(20 * time.Second),
+		10 * time.Second,
+		20 * time.Second,
 	}
 
 	log := zerolog.New(os.Stdout).With().
@@ -463,7 +518,7 @@ func ExampleContext_IPPrefix() {
 	// Output: {"Route":"192.168.0.0/24","message":"hello world"}
 }
 
-func ExampleContext_MacAddr() {
+func ExampleContext_MACAddr() {
 	mac := net.HardwareAddr{0x00, 0x14, 0x22, 0x01, 0x23, 0x45}
 	log := zerolog.New(os.Stdout).With().
 		MACAddr("hostMAC", mac).
@@ -473,3 +528,35 @@ func ExampleContext_MacAddr() {
 
 	// Output: {"hostMAC":"00:14:22:01:23:45","message":"hello world"}
 }
+
+func ExampleContext_Fields_map() {
+	fields := map[string]interface{}{
+		"bar": "baz",
+		"n":   1,
+	}
+
+	log := zerolog.New(os.Stdout).With().
+		Str("foo", "bar").
+		Fields(fields).
+		Logger()
+
+	log.Log().Msg("hello world")
+
+	// Output: {"foo":"bar","bar":"baz","n":1,"message":"hello world"}
+}
+
+func ExampleContext_Fields_slice() {
+	fields := []interface{}{
+		"bar", "baz",
+		"n", 1,
+	}
+
+	log := zerolog.New(os.Stdout).With().
+		Str("foo", "bar").
+		Fields(fields).
+		Logger()
+
+	log.Log().Msg("hello world")
+
+	// Output: {"foo":"bar","bar":"baz","n":1,"message":"hello world"}
+}

log_test.go

@@ -2,11 +2,14 @@ package zerolog
 
 import (
 	"bytes"
+	"context"
 	"errors"
 	"fmt"
 	"net"
 	"reflect"
 	"runtime"
+	"strconv"
+	"strings"
 	"testing"
 	"time"
 )
@@ -75,10 +78,30 @@ func TestInfo(t *testing.T) {
 	})
 }
 
+func TestEmptyLevelFieldName(t *testing.T) {
+	fieldName := LevelFieldName
+	LevelFieldName = ""
+
+	t.Run("empty setting", func(t *testing.T) {
+		out := &bytes.Buffer{}
+		log := New(out)
+		log.Info().
+			Str("foo", "bar").
+			Int("n", 123).
+			Msg("")
+		if got, want := decodeIfBinaryToString(out.Bytes()), `{"foo":"bar","n":123}`+"\n"; got != want {
+			t.Errorf("invalid log output:\ngot:  %v\nwant: %v", got, want)
+		}
+	})
+	LevelFieldName = fieldName
+}
+
 func TestWith(t *testing.T) {
 	out := &bytes.Buffer{}
 	ctx := New(out).With().
 		Str("string", "foo").
+		Stringer("stringer", net.IP{127, 0, 0, 1}).
+		Stringer("stringer_nil", nil).
 		Bytes("bytes", []byte("bar")).
 		Hex("hex", []byte{0x12, 0xef}).
 		RawJSON("json", []byte(`{"some":"json"}`)).
@@ -97,12 +120,46 @@ func TestWith(t *testing.T) {
 		Uint64("uint64", 10).
 		Float32("float32", 11.101).
 		Float64("float64", 12.30303).
-		Time("time", time.Time{})
+		Time("time", time.Time{}).
+		Ctx(context.Background())
 	_, file, line, _ := runtime.Caller(0)
 	caller := fmt.Sprintf("%s:%d", file, line+3)
 	log := ctx.Caller().Logger()
 	log.Log().Msg("")
-	if got, want := decodeIfBinaryToString(out.Bytes()), `{"string":"foo","bytes":"bar","hex":"12ef","json":{"some":"json"},"error":"some error","bool":true,"int":1,"int8":2,"int16":3,"int32":4,"int64":5,"uint":6,"uint8":7,"uint16":8,"uint32":9,"uint64":10,"float32":11.101,"float64":12.30303,"time":"0001-01-01T00:00:00Z","caller":"`+caller+`"}`+"\n"; got != want {
+	if got, want := decodeIfBinaryToString(out.Bytes()), `{"string":"foo","stringer":"127.0.0.1","stringer_nil":null,"bytes":"bar","hex":"12ef","json":{"some":"json"},"error":"some error","bool":true,"int":1,"int8":2,"int16":3,"int32":4,"int64":5,"uint":6,"uint8":7,"uint16":8,"uint32":9,"uint64":10,"float32":11.101,"float64":12.30303,"time":"0001-01-01T00:00:00Z","caller":"`+caller+`"}`+"\n"; got != want {
+		t.Errorf("invalid log output:\ngot:  %v\nwant: %v", got, want)
+	}
+
+	// Validate CallerWithSkipFrameCount.
+	out.Reset()
+	_, file, line, _ = runtime.Caller(0)
+	caller = fmt.Sprintf("%s:%d", file, line+5)
+	log = ctx.CallerWithSkipFrameCount(3).Logger()
+	func() {
+		log.Log().Msg("")
+	}()
+	// The above line is a little contrived, but the line above should be the line due
+	// to the extra frame skip.
+	if got, want := decodeIfBinaryToString(out.Bytes()), `{"string":"foo","stringer":"127.0.0.1","stringer_nil":null,"bytes":"bar","hex":"12ef","json":{"some":"json"},"error":"some error","bool":true,"int":1,"int8":2,"int16":3,"int32":4,"int64":5,"uint":6,"uint8":7,"uint16":8,"uint32":9,"uint64":10,"float32":11.101,"float64":12.30303,"time":"0001-01-01T00:00:00Z","caller":"`+caller+`"}`+"\n"; got != want {
+		t.Errorf("invalid log output:\ngot:  %v\nwant: %v", got, want)
+	}
+}
+
+func TestWithReset(t *testing.T) {
+	out := &bytes.Buffer{}
+	ctx := New(out).With().
+		Str("string", "foo").
+		Stringer("stringer", net.IP{127, 0, 0, 1}).
+		Stringer("stringer_nil", nil).
+		Reset().
+		Bytes("bytes", []byte("bar")).
+		Hex("hex", []byte{0x12, 0xef}).
+		Uint64("uint64", 10).
+		Float64("float64", 12.30303).
+		Ctx(context.Background())
+	log := ctx.Logger()
+	log.Log().Msg("")
+	if got, want := decodeIfBinaryToString(out.Bytes()), `{"bytes":"bar","hex":"12ef","uint64":10,"float64":12.30303}`+"\n"; got != want {
 		t.Errorf("invalid log output:\ngot:  %v\nwant: %v", got, want)
 	}
 }
@@ -210,6 +267,66 @@ func TestFieldsMapNilPnt(t *testing.T) {
 	}
 }
 
+func TestFieldsSlice(t *testing.T) {
+	out := &bytes.Buffer{}
+	log := New(out)
+	log.Log().Fields([]interface{}{
+		"nil", nil,
+		"string", "foo",
+		"bytes", []byte("bar"),
+		"error", errors.New("some error"),
+		"bool", true,
+		"int", int(1),
+		"int8", int8(2),
+		"int16", int16(3),
+		"int32", int32(4),
+		"int64", int64(5),
+		"uint", uint(6),
+		"uint8", uint8(7),
+		"uint16", uint16(8),
+		"uint32", uint32(9),
+		"uint64", uint64(10),
+		"float32", float32(11),
+		"float64", float64(12),
+		"ipv6", net.IP{0x20, 0x01, 0x0d, 0xb8, 0x85, 0xa3, 0x00, 0x00, 0x00, 0x00, 0x8a, 0x2e, 0x03, 0x70, 0x73, 0x34},
+		"dur", 1 * time.Second,
+		"time", time.Time{},
+		"obj", obj{"a", "b", 1},
+	}).Msg("")
+	if got, want := decodeIfBinaryToString(out.Bytes()), `{"nil":null,"string":"foo","bytes":"bar","error":"some error","bool":true,"int":1,"int8":2,"int16":3,"int32":4,"int64":5,"uint":6,"uint8":7,"uint16":8,"uint32":9,"uint64":10,"float32":11,"float64":12,"ipv6":"2001:db8:85a3::8a2e:370:7334","dur":1000,"time":"0001-01-01T00:00:00Z","obj":{"Pub":"a","Tag":"b","priv":1}}`+"\n"; got != want {
+		t.Errorf("invalid log output:\ngot:  %v\nwant: %v", got, want)
+	}
+}
+
+func TestFieldsSliceExtraneous(t *testing.T) {
+	out := &bytes.Buffer{}
+	log := New(out)
+	log.Log().Fields([]interface{}{
+		"string", "foo",
+		"error", errors.New("some error"),
+		32, "valueForNonStringKey",
+		"bool", true,
+		"int", int(1),
+		"keyWithoutValue",
+	}).Msg("")
+	if got, want := decodeIfBinaryToString(out.Bytes()), `{"string":"foo","error":"some error","bool":true,"int":1}`+"\n"; got != want {
+		t.Errorf("invalid log output:\ngot:  %v\nwant: %v", got, want)
+	}
+}
+
+func TestFieldsNotMapSlice(t *testing.T) {
+	out := &bytes.Buffer{}
+	log := New(out)
+	log.Log().
+		Fields(obj{"a", "b", 1}).
+		Fields("string").
+		Fields(1).
+		Msg("")
+	if got, want := decodeIfBinaryToString(out.Bytes()), `{}`+"\n"; got != want {
+		t.Errorf("invalid log output:\ngot:  %v\nwant: %v", got, want)
+	}
+}
+
 func TestFields(t *testing.T) {
 	out := &bytes.Buffer{}
 	log := New(out)
@@ -219,9 +336,13 @@ func TestFields(t *testing.T) {
 	log.Log().
 		Caller().
 		Str("string", "foo").
+		Stringer("stringer", net.IP{127, 0, 0, 1}).
+		Stringer("stringer_nil", nil).
 		Bytes("bytes", []byte("bar")).
 		Hex("hex", []byte{0x12, 0xef}).
 		RawJSON("json", []byte(`{"some":"json"}`)).
+		RawCBOR("cbor", []byte{0x83, 0x01, 0x82, 0x02, 0x03, 0x82, 0x04, 0x05}).
+		Func(func(e *Event) { e.Str("func", "func_output") }).
 		AnErr("some_err", nil).
 		Err(errors.New("some error")).
 		Bool("bool", true).
@@ -244,8 +365,9 @@ func TestFields(t *testing.T) {
 		Dur("dur", 1*time.Second).
 		Time("time", time.Time{}).
 		TimeDiff("diff", now, now.Add(-10*time.Second)).
+		Ctx(context.Background()).
 		Msg("")
-	if got, want := decodeIfBinaryToString(out.Bytes()), `{"caller":"`+caller+`","string":"foo","bytes":"bar","hex":"12ef","json":{"some":"json"},"error":"some error","bool":true,"int":1,"int8":2,"int16":3,"int32":4,"int64":5,"uint":6,"uint8":7,"uint16":8,"uint32":9,"uint64":10,"IPv4":"192.168.0.100","IPv6":"2001:db8:85a3::8a2e:370:7334","Mac":"00:14:22:01:23:45","Prefix":"192.168.0.100/24","float32":11.1234,"float64":12.321321321,"dur":1000,"time":"0001-01-01T00:00:00Z","diff":10000}`+"\n"; got != want {
+	if got, want := decodeIfBinaryToString(out.Bytes()), `{"caller":"`+caller+`","string":"foo","stringer":"127.0.0.1","stringer_nil":null,"bytes":"bar","hex":"12ef","json":{"some":"json"},"cbor":"data:application/cbor;base64,gwGCAgOCBAU=","func":"func_output","error":"some error","bool":true,"int":1,"int8":2,"int16":3,"int32":4,"int64":5,"uint":6,"uint8":7,"uint16":8,"uint32":9,"uint64":10,"IPv4":"192.168.0.100","IPv6":"2001:db8:85a3::8a2e:370:7334","Mac":"00:14:22:01:23:45","Prefix":"192.168.0.100/24","float32":11.1234,"float64":12.321321321,"dur":1000,"time":"0001-01-01T00:00:00Z","diff":10000}`+"\n"; got != want {
 		t.Errorf("invalid log output:\ngot:  %v\nwant: %v", got, want)
 	}
 }
@@ -255,6 +377,7 @@ func TestFieldsArrayEmpty(t *testing.T) {
 	log := New(out)
 	log.Log().
 		Strs("string", []string{}).
+		Stringers("stringer", []fmt.Stringer{}).
 		Errs("err", []error{}).
 		Bools("bool", []bool{}).
 		Ints("int", []int{}).
@@ -272,7 +395,7 @@ func TestFieldsArrayEmpty(t *testing.T) {
 		Durs("dur", []time.Duration{}).
 		Times("time", []time.Time{}).
 		Msg("")
-	if got, want := decodeIfBinaryToString(out.Bytes()), `{"string":[],"err":[],"bool":[],"int":[],"int8":[],"int16":[],"int32":[],"int64":[],"uint":[],"uint8":[],"uint16":[],"uint32":[],"uint64":[],"float32":[],"float64":[],"dur":[],"time":[]}`+"\n"; got != want {
+	if got, want := decodeIfBinaryToString(out.Bytes()), `{"string":[],"stringer":[],"err":[],"bool":[],"int":[],"int8":[],"int16":[],"int32":[],"int64":[],"uint":[],"uint8":[],"uint16":[],"uint32":[],"uint64":[],"float32":[],"float64":[],"dur":[],"time":[]}`+"\n"; got != want {
 		t.Errorf("invalid log output:\ngot:  %v\nwant: %v", got, want)
 	}
 }
@@ -282,6 +405,7 @@ func TestFieldsArraySingleElement(t *testing.T) {
 	log := New(out)
 	log.Log().
 		Strs("string", []string{"foo"}).
+		Stringers("stringer", []fmt.Stringer{net.IP{127, 0, 0, 1}}).
 		Errs("err", []error{errors.New("some error")}).
 		Bools("bool", []bool{true}).
 		Ints("int", []int{1}).
@@ -297,9 +421,9 @@ func TestFieldsArraySingleElement(t *testing.T) {
 		Floats32("float32", []float32{11}).
 		Floats64("float64", []float64{12}).
 		Durs("dur", []time.Duration{1 * time.Second}).
-		Times("time", []time.Time{time.Time{}}).
+		Times("time", []time.Time{{}}).
 		Msg("")
-	if got, want := decodeIfBinaryToString(out.Bytes()), `{"string":["foo"],"err":["some error"],"bool":[true],"int":[1],"int8":[2],"int16":[3],"int32":[4],"int64":[5],"uint":[6],"uint8":[7],"uint16":[8],"uint32":[9],"uint64":[10],"float32":[11],"float64":[12],"dur":[1000],"time":["0001-01-01T00:00:00Z"]}`+"\n"; got != want {
+	if got, want := decodeIfBinaryToString(out.Bytes()), `{"string":["foo"],"stringer":["127.0.0.1"],"err":["some error"],"bool":[true],"int":[1],"int8":[2],"int16":[3],"int32":[4],"int64":[5],"uint":[6],"uint8":[7],"uint16":[8],"uint32":[9],"uint64":[10],"float32":[11],"float64":[12],"dur":[1000],"time":["0001-01-01T00:00:00Z"]}`+"\n"; got != want {
 		t.Errorf("invalid log output:\ngot:  %v\nwant: %v", got, want)
 	}
 }
@@ -309,6 +433,7 @@ func TestFieldsArrayMultipleElement(t *testing.T) {
 	log := New(out)
 	log.Log().
 		Strs("string", []string{"foo", "bar"}).
+		Stringers("stringer", []fmt.Stringer{nil, net.IP{127, 0, 0, 1}}).
 		Errs("err", []error{errors.New("some error"), nil}).
 		Bools("bool", []bool{true, false}).
 		Ints("int", []int{1, 0}).
@@ -324,9 +449,9 @@ func TestFieldsArrayMultipleElement(t *testing.T) {
 		Floats32("float32", []float32{11, 0}).
 		Floats64("float64", []float64{12, 0}).
 		Durs("dur", []time.Duration{1 * time.Second, 0}).
-		Times("time", []time.Time{time.Time{}, time.Time{}}).
+		Times("time", []time.Time{{}, {}}).
 		Msg("")
-	if got, want := decodeIfBinaryToString(out.Bytes()), `{"string":["foo","bar"],"err":["some error",null],"bool":[true,false],"int":[1,0],"int8":[2,0],"int16":[3,0],"int32":[4,0],"int64":[5,0],"uint":[6,0],"uint8":[7,0],"uint16":[8,0],"uint32":[9,0],"uint64":[10,0],"float32":[11,0],"float64":[12,0],"dur":[1000,0],"time":["0001-01-01T00:00:00Z","0001-01-01T00:00:00Z"]}`+"\n"; got != want {
+	if got, want := decodeIfBinaryToString(out.Bytes()), `{"string":["foo","bar"],"stringer":[null,"127.0.0.1"],"err":["some error",null],"bool":[true,false],"int":[1,0],"int8":[2,0],"int16":[3,0],"int32":[4,0],"int64":[5,0],"uint":[6,0],"uint8":[7,0],"uint16":[8,0],"uint32":[9,0],"uint64":[10,0],"float32":[11,0],"float64":[12,0],"dur":[1000,0],"time":["0001-01-01T00:00:00Z","0001-01-01T00:00:00Z"]}`+"\n"; got != want {
 		t.Errorf("invalid log output:\ngot:  %v\nwant: %v", got, want)
 	}
 }
@@ -337,10 +462,12 @@ func TestFieldsDisabled(t *testing.T) {
 	now := time.Now()
 	log.Debug().
 		Str("string", "foo").
+		Stringer("stringer", net.IP{127, 0, 0, 1}).
 		Bytes("bytes", []byte("bar")).
 		Hex("hex", []byte{0x12, 0xef}).
 		AnErr("some_err", nil).
 		Err(errors.New("some error")).
+		Func(func(e *Event) { e.Str("func", "func_output") }).
 		Bool("bool", true).
 		Int("int", 1).
 		Int8("int8", 2).
@@ -357,6 +484,7 @@ func TestFieldsDisabled(t *testing.T) {
 		Dur("dur", 1*time.Second).
 		Time("time", time.Time{}).
 		TimeDiff("diff", now, now.Add(-10*time.Second)).
+		Ctx(context.Background()).
 		Msg("")
 	if got, want := decodeIfBinaryToString(out.Bytes()), ""; got != want {
 		t.Errorf("invalid log output:\ngot:  %v\nwant: %v", got, want)
@@ -437,6 +565,24 @@ func TestLevel(t *testing.T) {
 	})
 }
 
+func TestGetLevel(t *testing.T) {
+	levels := []Level{
+		DebugLevel,
+		InfoLevel,
+		WarnLevel,
+		ErrorLevel,
+		FatalLevel,
+		PanicLevel,
+		NoLevel,
+		Disabled,
+	}
+	for _, level := range levels {
+		if got, want := New(nil).Level(level).GetLevel(), level; got != want {
+			t.Errorf("GetLevel() = %v, want: %v", got, want)
+		}
+	}
+}
+
 func TestSampling(t *testing.T) {
 	out := &bytes.Buffer{}
 	log := New(out).Sample(&BasicSampler{N: 2})
@@ -491,32 +637,45 @@ func TestLevelWriter(t *testing.T) {
 			p string
 		}{},
 	}
-	log := New(lw)
+
+	// Allow extra-verbose logs.
+	SetGlobalLevel(TraceLevel - 1)
+	log := New(lw).Level(TraceLevel - 1)
+
+	log.Trace().Msg("0")
 	log.Debug().Msg("1")
 	log.Info().Msg("2")
 	log.Warn().Msg("3")
 	log.Error().Msg("4")
 	log.Log().Msg("nolevel-1")
-	log.WithLevel(DebugLevel).Msg("5")
-	log.WithLevel(InfoLevel).Msg("6")
-	log.WithLevel(WarnLevel).Msg("7")
-	log.WithLevel(ErrorLevel).Msg("8")
+	log.WithLevel(TraceLevel).Msg("5")
+	log.WithLevel(DebugLevel).Msg("6")
+	log.WithLevel(InfoLevel).Msg("7")
+	log.WithLevel(WarnLevel).Msg("8")
+	log.WithLevel(ErrorLevel).Msg("9")
 	log.WithLevel(NoLevel).Msg("nolevel-2")
+	log.WithLevel(-1).Msg("-1") // Same as TraceLevel
+	log.WithLevel(-2).Msg("-2") // Will log
+	log.WithLevel(-3).Msg("-3") // Will not log
 
 	want := []struct {
 		l Level
 		p string
 	}{
+		{TraceLevel, `{"level":"trace","message":"0"}` + "\n"},
 		{DebugLevel, `{"level":"debug","message":"1"}` + "\n"},
 		{InfoLevel, `{"level":"info","message":"2"}` + "\n"},
 		{WarnLevel, `{"level":"warn","message":"3"}` + "\n"},
 		{ErrorLevel, `{"level":"error","message":"4"}` + "\n"},
 		{NoLevel, `{"message":"nolevel-1"}` + "\n"},
-		{DebugLevel, `{"level":"debug","message":"5"}` + "\n"},
-		{InfoLevel, `{"level":"info","message":"6"}` + "\n"},
-		{WarnLevel, `{"level":"warn","message":"7"}` + "\n"},
-		{ErrorLevel, `{"level":"error","message":"8"}` + "\n"},
+		{TraceLevel, `{"level":"trace","message":"5"}` + "\n"},
+		{DebugLevel, `{"level":"debug","message":"6"}` + "\n"},
+		{InfoLevel, `{"level":"info","message":"7"}` + "\n"},
+		{WarnLevel, `{"level":"warn","message":"8"}` + "\n"},
+		{ErrorLevel, `{"level":"error","message":"9"}` + "\n"},
 		{NoLevel, `{"message":"nolevel-2"}` + "\n"},
+		{Level(-1), `{"level":"trace","message":"-1"}` + "\n"},
+		{Level(-2), `{"level":"-2","message":"-2"}` + "\n"},
 	}
 	if got := lw.ops; !reflect.DeepEqual(got, want) {
 		t.Errorf("invalid ops:\ngot:\n%v\nwant:\n%v", got, want)
@@ -641,6 +800,75 @@ func TestErrorMarshalFunc(t *testing.T) {
 	}
 }
 
+func TestCallerMarshalFunc(t *testing.T) {
+	out := &bytes.Buffer{}
+	log := New(out)
+
+	// test default behaviour this is really brittle due to the line numbers
+	// actually mattering for validation
+	pc, file, line, _ := runtime.Caller(0)
+	caller := fmt.Sprintf("%s:%d", file, line+2)
+	log.Log().Caller().Msg("msg")
+	if got, want := decodeIfBinaryToString(out.Bytes()), `{"caller":"`+caller+`","message":"msg"}`+"\n"; got != want {
+		t.Errorf("invalid log output:\ngot:  %v\nwant: %v", got, want)
+	}
+	out.Reset()
+
+	// test custom behavior. In this case we'll take just the last directory
+	origCallerMarshalFunc := CallerMarshalFunc
+	defer func() { CallerMarshalFunc = origCallerMarshalFunc }()
+	CallerMarshalFunc = func(pc uintptr, file string, line int) string {
+		parts := strings.Split(file, "/")
+		if len(parts) > 1 {
+			return strings.Join(parts[len(parts)-2:], "/") + ":" + strconv.Itoa(line)
+		}
+
+		return runtime.FuncForPC(pc).Name() + ":" + file + ":" + strconv.Itoa(line)
+	}
+	pc, file, line, _ = runtime.Caller(0)
+	caller = CallerMarshalFunc(pc, file, line+2)
+	log.Log().Caller().Msg("msg")
+	if got, want := decodeIfBinaryToString(out.Bytes()), `{"caller":"`+caller+`","message":"msg"}`+"\n"; got != want {
+		t.Errorf("invalid log output:\ngot:  %v\nwant: %v", got, want)
+	}
+}
+
+func TestLevelFieldMarshalFunc(t *testing.T) {
+	origLevelFieldMarshalFunc := LevelFieldMarshalFunc
+	LevelFieldMarshalFunc = func(l Level) string {
+		return strings.ToUpper(l.String())
+	}
+	defer func() {
+		LevelFieldMarshalFunc = origLevelFieldMarshalFunc
+	}()
+	out := &bytes.Buffer{}
+	log := New(out)
+
+	log.Debug().Msg("test")
+	if got, want := decodeIfBinaryToString(out.Bytes()), `{"level":"DEBUG","message":"test"}`+"\n"; got != want {
+		t.Errorf("invalid log output:\ngot:  %v\nwant: %v", got, want)
+	}
+	out.Reset()
+
+	log.Info().Msg("test")
+	if got, want := decodeIfBinaryToString(out.Bytes()), `{"level":"INFO","message":"test"}`+"\n"; got != want {
+		t.Errorf("invalid log output:\ngot:  %v\nwant: %v", got, want)
+	}
+	out.Reset()
+
+	log.Warn().Msg("test")
+	if got, want := decodeIfBinaryToString(out.Bytes()), `{"level":"WARN","message":"test"}`+"\n"; got != want {
+		t.Errorf("invalid log output:\ngot:  %v\nwant: %v", got, want)
+	}
+	out.Reset()
+
+	log.Error().Msg("test")
+	if got, want := decodeIfBinaryToString(out.Bytes()), `{"level":"ERROR","message":"test"}`+"\n"; got != want {
+		t.Errorf("invalid log output:\ngot:  %v\nwant: %v", got, want)
+	}
+	out.Reset()
+}
+
 type errWriter struct {
 	error
 }
@@ -661,3 +889,155 @@ func TestErrorHandler(t *testing.T) {
 		t.Errorf("ErrorHandler err = %#v, want %#v", got, want)
 	}
 }
+
+func TestUpdateEmptyContext(t *testing.T) {
+	var buf bytes.Buffer
+	log := New(&buf)
+
+	log.UpdateContext(func(c Context) Context {
+		return c.Str("foo", "bar")
+	})
+	log.Info().Msg("no panic")
+
+	want := `{"level":"info","foo":"bar","message":"no panic"}` + "\n"
+
+	if got := decodeIfBinaryToString(buf.Bytes()); got != want {
+		t.Errorf("invalid log output:\ngot:  %q\nwant: %q", got, want)
+	}
+}
+
+func TestLevel_String(t *testing.T) {
+	tests := []struct {
+		name string
+		l    Level
+		want string
+	}{
+		{"trace", TraceLevel, "trace"},
+		{"debug", DebugLevel, "debug"},
+		{"info", InfoLevel, "info"},
+		{"warn", WarnLevel, "warn"},
+		{"error", ErrorLevel, "error"},
+		{"fatal", FatalLevel, "fatal"},
+		{"panic", PanicLevel, "panic"},
+		{"disabled", Disabled, "disabled"},
+		{"nolevel", NoLevel, ""},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			if got := tt.l.String(); got != tt.want {
+				t.Errorf("String() = %v, want %v", got, tt.want)
+			}
+		})
+	}
+}
+
+func TestLevel_MarshalText(t *testing.T) {
+	tests := []struct {
+		name string
+		l    Level
+		want string
+	}{
+		{"trace", TraceLevel, "trace"},
+		{"debug", DebugLevel, "debug"},
+		{"info", InfoLevel, "info"},
+		{"warn", WarnLevel, "warn"},
+		{"error", ErrorLevel, "error"},
+		{"fatal", FatalLevel, "fatal"},
+		{"panic", PanicLevel, "panic"},
+		{"disabled", Disabled, "disabled"},
+		{"nolevel", NoLevel, ""},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			if got, err := tt.l.MarshalText(); err != nil {
+				t.Errorf("MarshalText couldn't marshal: %v", tt.l)
+			} else if string(got) != tt.want {
+				t.Errorf("String() = %v, want %v", string(got), tt.want)
+			}
+		})
+	}
+}
+
+func TestParseLevel(t *testing.T) {
+	type args struct {
+		levelStr string
+	}
+	tests := []struct {
+		name    string
+		args    args
+		want    Level
+		wantErr bool
+	}{
+		{"trace", args{"trace"}, TraceLevel, false},
+		{"debug", args{"debug"}, DebugLevel, false},
+		{"info", args{"info"}, InfoLevel, false},
+		{"warn", args{"warn"}, WarnLevel, false},
+		{"error", args{"error"}, ErrorLevel, false},
+		{"fatal", args{"fatal"}, FatalLevel, false},
+		{"panic", args{"panic"}, PanicLevel, false},
+		{"disabled", args{"disabled"}, Disabled, false},
+		{"nolevel", args{""}, NoLevel, false},
+		{"-1", args{"-1"}, TraceLevel, false},
+		{"-2", args{"-2"}, Level(-2), false},
+		{"-3", args{"-3"}, Level(-3), false},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			got, err := ParseLevel(tt.args.levelStr)
+			if (err != nil) != tt.wantErr {
+				t.Errorf("ParseLevel() error = %v, wantErr %v", err, tt.wantErr)
+				return
+			}
+			if got != tt.want {
+				t.Errorf("ParseLevel() got = %v, want %v", got, tt.want)
+			}
+		})
+	}
+}
+
+func TestUnmarshalTextLevel(t *testing.T) {
+	type args struct {
+		levelStr string
+	}
+	tests := []struct {
+		name    string
+		args    args
+		want    Level
+		wantErr bool
+	}{
+		{"trace", args{"trace"}, TraceLevel, false},
+		{"debug", args{"debug"}, DebugLevel, false},
+		{"info", args{"info"}, InfoLevel, false},
+		{"warn", args{"warn"}, WarnLevel, false},
+		{"error", args{"error"}, ErrorLevel, false},
+		{"fatal", args{"fatal"}, FatalLevel, false},
+		{"panic", args{"panic"}, PanicLevel, false},
+		{"disabled", args{"disabled"}, Disabled, false},
+		{"nolevel", args{""}, NoLevel, false},
+		{"-1", args{"-1"}, TraceLevel, false},
+		{"-2", args{"-2"}, Level(-2), false},
+		{"-3", args{"-3"}, Level(-3), false},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			var l Level
+			err := l.UnmarshalText([]byte(tt.args.levelStr))
+			if (err != nil) != tt.wantErr {
+				t.Errorf("UnmarshalText() error = %v, wantErr %v", err, tt.wantErr)
+				return
+			}
+			if l != tt.want {
+				t.Errorf("UnmarshalText() got = %v, want %v", l, tt.want)
+			}
+		})
+	}
+}
+
+func TestHTMLNoEscaping(t *testing.T) {
+	out := &bytes.Buffer{}
+	log := New(out)
+	log.Log().Interface("head", "<test>").Send()
+	if got, want := decodeIfBinaryToString(out.Bytes()), `{"head":"<test>"}`+"\n"; got != want {
+		t.Errorf("invalid log output:\ngot:  %v\nwant: %v", got, want)
+	}
+}

not_go112.go

@@ -0,0 +1,5 @@
+// +build !go1.12
+
+package zerolog
+
+const contextCallerSkipFrameCount = 3

pkgerrors/stacktrace.go

@@ -0,0 +1,82 @@
+package pkgerrors
+
+import (
+	"github.com/pkg/errors"
+)
+
+var (
+	StackSourceFileName     = "source"
+	StackSourceLineName     = "line"
+	StackSourceFunctionName = "func"
+)
+
+type state struct {
+	b []byte
+}
+
+// Write implement fmt.Formatter interface.
+func (s *state) Write(b []byte) (n int, err error) {
+	s.b = b
+	return len(b), nil
+}
+
+// Width implement fmt.Formatter interface.
+func (s *state) Width() (wid int, ok bool) {
+	return 0, false
+}
+
+// Precision implement fmt.Formatter interface.
+func (s *state) Precision() (prec int, ok bool) {
+	return 0, false
+}
+
+// Flag implement fmt.Formatter interface.
+func (s *state) Flag(c int) bool {
+	return false
+}
+
+func frameField(f errors.Frame, s *state, c rune) string {
+	f.Format(s, c)
+	return string(s.b)
+}
+
+// MarshalStack implements pkg/errors stack trace marshaling.
+//
+// zerolog.ErrorStackMarshaler = MarshalStack
+func MarshalStack(err error) interface{} {
+	type stackTracer interface {
+		StackTrace() errors.StackTrace
+	}
+	var sterr stackTracer
+	var ok bool
+	for err != nil {
+		sterr, ok = err.(stackTracer)
+		if ok {
+			break
+		}
+
+		u, ok := err.(interface {
+			Unwrap() error
+		})
+		if !ok {
+			return nil
+		}
+
+		err = u.Unwrap()
+	}
+	if sterr == nil {
+		return nil
+	}
+
+	st := sterr.StackTrace()
+	s := &state{}
+	out := make([]map[string]string, 0, len(st))
+	for _, frame := range st {
+		out = append(out, map[string]string{
+			StackSourceFileName:     frameField(frame, s, 's'),
+			StackSourceLineName:     frameField(frame, s, 'd'),
+			StackSourceFunctionName: frameField(frame, s, 'n'),
+		})
+	}
+	return out
+}

pkgerrors/stacktrace_test.go

@@ -0,0 +1,90 @@
+// +build !binary_log
+
+package pkgerrors
+
+import (
+	"bytes"
+	"fmt"
+	"regexp"
+	"testing"
+
+	"github.com/pkg/errors"
+	"github.com/rs/zerolog"
+)
+
+func TestLogStack(t *testing.T) {
+	zerolog.ErrorStackMarshaler = MarshalStack
+
+	out := &bytes.Buffer{}
+	log := zerolog.New(out)
+
+	err := fmt.Errorf("from error: %w", errors.New("error message"))
+	log.Log().Stack().Err(err).Msg("")
+
+	got := out.String()
+	want := `\{"stack":\[\{"func":"TestLogStack","line":"21","source":"stacktrace_test.go"\},.*\],"error":"from error: error message"\}\n`
+	if ok, _ := regexp.MatchString(want, got); !ok {
+		t.Errorf("invalid log output:\ngot:  %v\nwant: %v", got, want)
+	}
+}
+
+func TestLogStackFields(t *testing.T) {
+	zerolog.ErrorStackMarshaler = MarshalStack
+
+	out := &bytes.Buffer{}
+	log := zerolog.New(out)
+
+	err := fmt.Errorf("from error: %w", errors.New("error message"))
+	log.Log().Stack().Fields([]interface{}{"error", err}).Msg("")
+
+	got := out.String()
+	want := `\{"error":"from error: error message","stack":\[\{"func":"TestLogStackFields","line":"37","source":"stacktrace_test.go"\},.*\]\}\n`
+	if ok, _ := regexp.MatchString(want, got); !ok {
+		t.Errorf("invalid log output:\ngot:  %v\nwant: %v", got, want)
+	}
+}
+
+func TestLogStackFromContext(t *testing.T) {
+	zerolog.ErrorStackMarshaler = MarshalStack
+
+	out := &bytes.Buffer{}
+	log := zerolog.New(out).With().Stack().Logger() // calling Stack() on log context instead of event
+
+	err := fmt.Errorf("from error: %w", errors.New("error message"))
+	log.Log().Err(err).Msg("") // not explicitly calling Stack()
+
+	got := out.String()
+	want := `\{"stack":\[\{"func":"TestLogStackFromContext","line":"53","source":"stacktrace_test.go"\},.*\],"error":"from error: error message"\}\n`
+	if ok, _ := regexp.MatchString(want, got); !ok {
+		t.Errorf("invalid log output:\ngot:  %v\nwant: %v", got, want)
+	}
+}
+
+func TestLogStackFromContextWith(t *testing.T) {
+	zerolog.ErrorStackMarshaler = MarshalStack
+
+	err := fmt.Errorf("from error: %w", errors.New("error message"))
+	out := &bytes.Buffer{}
+	log := zerolog.New(out).With().Stack().Err(err).Logger() // calling Stack() on log context instead of event
+
+	log.Error().Msg("")
+
+	got := out.String()
+	want := `\{"level":"error","stack":\[\{"func":"TestLogStackFromContextWith","line":"66","source":"stacktrace_test.go"\},.*\],"error":"from error: error message"\}\n`
+	if ok, _ := regexp.MatchString(want, got); !ok {
+		t.Errorf("invalid log output:\ngot:  %v\nwant: %v", got, want)
+	}
+}
+
+func BenchmarkLogStack(b *testing.B) {
+	zerolog.ErrorStackMarshaler = MarshalStack
+	out := &bytes.Buffer{}
+	log := zerolog.New(out)
+	err := errors.Wrap(errors.New("error message"), "from error")
+	b.ReportAllocs()
+
+	for i := 0; i < b.N; i++ {
+		log.Log().Stack().Err(err).Msg("")
+		out.Reset()
+	}
+}

sampler.go

@@ -38,7 +38,7 @@ func (s RandomSampler) Sample(lvl Level) bool {
 }
 
 // BasicSampler is a sampler that will send every Nth events, regardless of
-// there level.
+// their level.
 type BasicSampler struct {
 	N       uint32
 	counter uint32
@@ -46,8 +46,12 @@ type BasicSampler struct {
 
 // Sample implements the Sampler interface.
 func (s *BasicSampler) Sample(lvl Level) bool {
+	n := s.N
+	if n == 1 {
+		return true
+	}
 	c := atomic.AddUint32(&s.counter, 1)
-	return c%s.N == s.N-1
+	return c%n == 1
 }
 
 // BurstSampler lets Burst events pass per Period then pass the decision to
@@ -80,7 +84,7 @@ func (s *BurstSampler) Sample(lvl Level) bool {
 }
 
 func (s *BurstSampler) inc() uint32 {
-	now := time.Now().UnixNano()
+	now := TimestampFunc().UnixNano()
 	resetAt := atomic.LoadInt64(&s.resetAt)
 	var c uint32
 	if now > resetAt {
@@ -100,11 +104,15 @@ func (s *BurstSampler) inc() uint32 {
 
 // LevelSampler applies a different sampler for each level.
 type LevelSampler struct {
-	DebugSampler, InfoSampler, WarnSampler, ErrorSampler Sampler
+	TraceSampler, DebugSampler, InfoSampler, WarnSampler, ErrorSampler Sampler
 }
 
 func (s LevelSampler) Sample(lvl Level) bool {
 	switch lvl {
+	case TraceLevel:
+		if s.TraceSampler != nil {
+			return s.TraceSampler.Sample(lvl)
+		}
 	case DebugLevel:
 		if s.DebugSampler != nil {
 			return s.DebugSampler.Sample(lvl)

syslog.go

@@ -7,6 +7,10 @@ import (
 	"io"
 )
 
+// See http://cee.mitre.org/language/1.0-beta1/clt.html#syslog
+// or https://www.rsyslog.com/json-elasticsearch/
+const ceePrefix = "@cee:"
+
 // SyslogWriter is an interface matching a syslog.Writer struct.
 type SyslogWriter interface {
 	io.Writer
@@ -19,39 +23,67 @@ type SyslogWriter interface {
 }
 
 type syslogWriter struct {
-	w SyslogWriter
+	w      SyslogWriter
+	prefix string
 }
 
 // SyslogLevelWriter wraps a SyslogWriter and call the right syslog level
 // method matching the zerolog level.
 func SyslogLevelWriter(w SyslogWriter) LevelWriter {
-	return syslogWriter{w}
+	return syslogWriter{w, ""}
+}
+
+// SyslogCEEWriter wraps a SyslogWriter with a SyslogLevelWriter that adds a
+// MITRE CEE prefix for JSON syslog entries, compatible with rsyslog 
+// and syslog-ng JSON logging support. 
+// See https://www.rsyslog.com/json-elasticsearch/
+func SyslogCEEWriter(w SyslogWriter) LevelWriter {
+	return syslogWriter{w, ceePrefix}
 }
 
 func (sw syslogWriter) Write(p []byte) (n int, err error) {
-	return sw.w.Write(p)
+	var pn int
+	if sw.prefix != "" {
+		pn, err = sw.w.Write([]byte(sw.prefix))
+		if err != nil {
+			return pn, err
+		}
+	}
+	n, err = sw.w.Write(p)
+	return pn + n, err
 }
 
 // WriteLevel implements LevelWriter interface.
 func (sw syslogWriter) WriteLevel(level Level, p []byte) (n int, err error) {
 	switch level {
+	case TraceLevel:
 	case DebugLevel:
-		err = sw.w.Debug(string(p))
+		err = sw.w.Debug(sw.prefix + string(p))
 	case InfoLevel:
-		err = sw.w.Info(string(p))
+		err = sw.w.Info(sw.prefix + string(p))
 	case WarnLevel:
-		err = sw.w.Warning(string(p))
+		err = sw.w.Warning(sw.prefix + string(p))
 	case ErrorLevel:
-		err = sw.w.Err(string(p))
+		err = sw.w.Err(sw.prefix + string(p))
 	case FatalLevel:
-		err = sw.w.Emerg(string(p))
+		err = sw.w.Emerg(sw.prefix + string(p))
 	case PanicLevel:
-		err = sw.w.Crit(string(p))
+		err = sw.w.Crit(sw.prefix + string(p))
 	case NoLevel:
-		err = sw.w.Info(string(p))
+		err = sw.w.Info(sw.prefix + string(p))
 	default:
 		panic("invalid level")
 	}
+	// Any CEE prefix is not part of the message, so we don't include its length
 	n = len(p)
 	return
 }
+
+// Call the underlying writer's Close method if it is an io.Closer. Otherwise
+// does nothing.
+func (sw syslogWriter) Close() error {
+	if c, ok := sw.w.(io.Closer); ok {
+		return c.Close()
+	}
+	return nil
+}

syslog_test.go

@@ -3,8 +3,12 @@
 
 package zerolog
 
-import "testing"
-import "reflect"
+import (
+	"bytes"
+	"reflect"
+	"strings"
+	"testing"
+)
 
 type syslogEvent struct {
 	level string
@@ -17,6 +21,10 @@ type syslogTestWriter struct {
 func (w *syslogTestWriter) Write(p []byte) (int, error) {
 	return 0, nil
 }
+func (w *syslogTestWriter) Trace(m string) error {
+	w.events = append(w.events, syslogEvent{"Trace", m})
+	return nil
+}
 func (w *syslogTestWriter) Debug(m string) error {
 	w.events = append(w.events, syslogEvent{"Debug", m})
 	return nil
@@ -45,6 +53,7 @@ func (w *syslogTestWriter) Crit(m string) error {
 func TestSyslogWriter(t *testing.T) {
 	sw := &syslogTestWriter{}
 	log := New(SyslogLevelWriter(sw))
+	log.Trace().Msg("trace")
 	log.Debug().Msg("debug")
 	log.Info().Msg("info")
 	log.Warn().Msg("warn")
@@ -61,3 +70,39 @@ func TestSyslogWriter(t *testing.T) {
 		t.Errorf("Invalid syslog message routing: want %v, got %v", want, got)
 	}
 }
+
+type testCEEwriter struct {
+	buf *bytes.Buffer
+}
+
+// Only implement one method as we're just testing the prefixing
+func (c testCEEwriter) Debug(m string) error { return nil }
+
+func (c testCEEwriter) Info(m string) error {
+	_, err := c.buf.Write([]byte(m))
+	return err
+}
+
+func (c testCEEwriter) Warning(m string) error { return nil }
+
+func (c testCEEwriter) Err(m string) error { return nil }
+
+func (c testCEEwriter) Emerg(m string) error { return nil }
+
+func (c testCEEwriter) Crit(m string) error { return nil }
+
+func (c testCEEwriter) Write(b []byte) (int, error) {
+	return c.buf.Write(b)
+}
+
+func TestSyslogWriter_WithCEE(t *testing.T) {
+	var buf bytes.Buffer
+	sw := testCEEwriter{&buf}
+	log := New(SyslogCEEWriter(sw))
+	log.Info().Str("key", "value").Msg("message string")
+	got := buf.String()
+	want := "@cee:{"
+	if !strings.HasPrefix(got, want) {
+		t.Errorf("Bad CEE message start: want %v, got %v", want, got)
+	}
+}

writer.go

@@ -1,7 +1,12 @@
 package zerolog
 
 import (
+	"bytes"
 	"io"
+	"path"
+	"runtime"
+	"strconv"
+	"strings"
 	"sync"
 )
 
@@ -12,30 +17,39 @@ type LevelWriter interface {
 	WriteLevel(level Level, p []byte) (n int, err error)
 }
 
-type levelWriterAdapter struct {
+// LevelWriterAdapter adapts an io.Writer to support the LevelWriter interface.
+type LevelWriterAdapter struct {
 	io.Writer
 }
 
-func (lw levelWriterAdapter) WriteLevel(l Level, p []byte) (n int, err error) {
+// WriteLevel simply writes everything to the adapted writer, ignoring the level.
+func (lw LevelWriterAdapter) WriteLevel(l Level, p []byte) (n int, err error) {
 	return lw.Write(p)
 }
 
+// Call the underlying writer's Close method if it is an io.Closer. Otherwise
+// does nothing.
+func (lw LevelWriterAdapter) Close() error {
+	if closer, ok := lw.Writer.(io.Closer); ok {
+		return closer.Close()
+	}
+	return nil
+}
+
 type syncWriter struct {
 	mu sync.Mutex
 	lw LevelWriter
 }
 
 // SyncWriter wraps w so that each call to Write is synchronized with a mutex.
-// This syncer can be the call to writer's Write method is not thread safe.
-// Note that os.File Write operation is using write() syscall which is supposed
-// to be thread-safe on POSIX systems. So there is no need to use this with
-// os.File on such systems as zerolog guaranties to issue a single Write call
-// per log event.
+// This syncer can be used to wrap the call to writer's Write method if it is
+// not thread safe. Note that you do not need this wrapper for os.File Write
+// operations on POSIX and Windows systems as they are already thread-safe.
 func SyncWriter(w io.Writer) io.Writer {
 	if lw, ok := w.(LevelWriter); ok {
 		return &syncWriter{lw: lw}
 	}
-	return &syncWriter{lw: levelWriterAdapter{w}}
+	return &syncWriter{lw: LevelWriterAdapter{w}}
 }
 
 // Write implements the io.Writer interface.
@@ -52,36 +66,59 @@ func (s *syncWriter) WriteLevel(l Level, p []byte) (n int, err error) {
 	return s.lw.WriteLevel(l, p)
 }
 
+func (s *syncWriter) Close() error {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	if closer, ok := s.lw.(io.Closer); ok {
+		return closer.Close()
+	}
+	return nil
+}
+
 type multiLevelWriter struct {
 	writers []LevelWriter
 }
 
 func (t multiLevelWriter) Write(p []byte) (n int, err error) {
 	for _, w := range t.writers {
-		n, err = w.Write(p)
-		if err != nil {
-			return
-		}
-		if n != len(p) {
-			err = io.ErrShortWrite
-			return
+		if _n, _err := w.Write(p); err == nil {
+			n = _n
+			if _err != nil {
+				err = _err
+			} else if _n != len(p) {
+				err = io.ErrShortWrite
+			}
 		}
 	}
-	return len(p), nil
+	return n, err
 }
 
 func (t multiLevelWriter) WriteLevel(l Level, p []byte) (n int, err error) {
 	for _, w := range t.writers {
-		n, err = w.WriteLevel(l, p)
-		if err != nil {
-			return
-		}
-		if n != len(p) {
-			err = io.ErrShortWrite
-			return
+		if _n, _err := w.WriteLevel(l, p); err == nil {
+			n = _n
+			if _err != nil {
+				err = _err
+			} else if _n != len(p) {
+				err = io.ErrShortWrite
+			}
 		}
 	}
-	return len(p), nil
+	return n, err
+}
+
+// Calls close on all the underlying writers that are io.Closers. If any of the
+// Close methods return an error, the remainder of the closers are not closed
+// and the error is returned.
+func (t multiLevelWriter) Close() error {
+	for _, w := range t.writers {
+		if closer, ok := w.(io.Closer); ok {
+			if err := closer.Close(); err != nil {
+				return err
+			}
+		}
+	}
+	return nil
 }
 
 // MultiLevelWriter creates a writer that duplicates its writes to all the
@@ -93,8 +130,217 @@ func MultiLevelWriter(writers ...io.Writer) LevelWriter {
 		if lw, ok := w.(LevelWriter); ok {
 			lwriters = append(lwriters, lw)
 		} else {
-			lwriters = append(lwriters, levelWriterAdapter{w})
+			lwriters = append(lwriters, LevelWriterAdapter{w})
 		}
 	}
 	return multiLevelWriter{lwriters}
 }
+
+// TestingLog is the logging interface of testing.TB.
+type TestingLog interface {
+	Log(args ...interface{})
+	Logf(format string, args ...interface{})
+	Helper()
+}
+
+// TestWriter is a writer that writes to testing.TB.
+type TestWriter struct {
+	T TestingLog
+
+	// Frame skips caller frames to capture the original file and line numbers.
+	Frame int
+}
+
+// NewTestWriter creates a writer that logs to the testing.TB.
+func NewTestWriter(t TestingLog) TestWriter {
+	return TestWriter{T: t}
+}
+
+// Write to testing.TB.
+func (t TestWriter) Write(p []byte) (n int, err error) {
+	t.T.Helper()
+
+	n = len(p)
+
+	// Strip trailing newline because t.Log always adds one.
+	p = bytes.TrimRight(p, "\n")
+
+	// Try to correct the log file and line number to the caller.
+	if t.Frame > 0 {
+		_, origFile, origLine, _ := runtime.Caller(1)
+		_, frameFile, frameLine, ok := runtime.Caller(1 + t.Frame)
+		if ok {
+			erase := strings.Repeat("\b", len(path.Base(origFile))+len(strconv.Itoa(origLine))+3)
+			t.T.Logf("%s%s:%d: %s", erase, path.Base(frameFile), frameLine, p)
+			return n, err
+		}
+	}
+	t.T.Log(string(p))
+
+	return n, err
+}
+
+// ConsoleTestWriter creates an option that correctly sets the file frame depth for testing.TB log.
+func ConsoleTestWriter(t TestingLog) func(w *ConsoleWriter) {
+	return func(w *ConsoleWriter) {
+		w.Out = TestWriter{T: t, Frame: 6}
+	}
+}
+
+// FilteredLevelWriter writes only logs at Level or above to Writer.
+//
+// It should be used only in combination with MultiLevelWriter when you
+// want to write to multiple destinations at different levels. Otherwise
+// you should just set the level on the logger and filter events early.
+// When using MultiLevelWriter then you set the level on the logger to
+// the lowest of the levels you use for writers.
+type FilteredLevelWriter struct {
+	Writer LevelWriter
+	Level  Level
+}
+
+// Write writes to the underlying Writer.
+func (w *FilteredLevelWriter) Write(p []byte) (int, error) {
+	return w.Writer.Write(p)
+}
+
+// WriteLevel calls WriteLevel of the underlying Writer only if the level is equal
+// or above the Level.
+func (w *FilteredLevelWriter) WriteLevel(level Level, p []byte) (int, error) {
+	if level >= w.Level {
+		return w.Writer.WriteLevel(level, p)
+	}
+	return len(p), nil
+}
+
+var triggerWriterPool = &sync.Pool{
+	New: func() interface{} {
+		return bytes.NewBuffer(make([]byte, 0, 1024))
+	},
+}
+
+// TriggerLevelWriter buffers log lines at the ConditionalLevel or below
+// until a trigger level (or higher) line is emitted. Log lines with level
+// higher than ConditionalLevel are always written out to the destination
+// writer. If trigger never happens, buffered log lines are never written out.
+//
+// It can be used to configure "log level per request".
+type TriggerLevelWriter struct {
+	// Destination writer. If LevelWriter is provided (usually), its WriteLevel is used
+	// instead of Write.
+	io.Writer
+
+	// ConditionalLevel is the level (and below) at which lines are buffered until
+	// a trigger level (or higher) line is emitted. Usually this is set to DebugLevel.
+	ConditionalLevel Level
+
+	// TriggerLevel is the lowest level that triggers the sending of the conditional
+	// level lines. Usually this is set to ErrorLevel.
+	TriggerLevel Level
+
+	buf       *bytes.Buffer
+	triggered bool
+	mu        sync.Mutex
+}
+
+func (w *TriggerLevelWriter) WriteLevel(l Level, p []byte) (n int, err error) {
+	w.mu.Lock()
+	defer w.mu.Unlock()
+
+	// At first trigger level or above log line, we flush the buffer and change the
+	// trigger state to triggered.
+	if !w.triggered && l >= w.TriggerLevel {
+		err := w.trigger()
+		if err != nil {
+			return 0, err
+		}
+	}
+
+	// Unless triggered, we buffer everything at and below ConditionalLevel.
+	if !w.triggered && l <= w.ConditionalLevel {
+		if w.buf == nil {
+			w.buf = triggerWriterPool.Get().(*bytes.Buffer)
+		}
+
+		// We prefix each log line with a byte with the level.
+		// Hopefully we will never have a level value which equals a newline
+		// (which could interfere with reconstruction of log lines in the trigger method).
+		w.buf.WriteByte(byte(l))
+		w.buf.Write(p)
+		return len(p), nil
+	}
+
+	// Anything above ConditionalLevel is always passed through.
+	// Once triggered, everything is passed through.
+	if lw, ok := w.Writer.(LevelWriter); ok {
+		return lw.WriteLevel(l, p)
+	}
+	return w.Write(p)
+}
+
+// trigger expects lock to be held.
+func (w *TriggerLevelWriter) trigger() error {
+	if w.triggered {
+		return nil
+	}
+	w.triggered = true
+
+	if w.buf == nil {
+		return nil
+	}
+
+	p := w.buf.Bytes()
+	for len(p) > 0 {
+		// We do not use bufio.Scanner here because we already have full buffer
+		// in the memory and we do not want extra copying from the buffer to
+		// scanner's token slice, nor we want to hit scanner's token size limit,
+		// and we also want to preserve newlines.
+		i := bytes.IndexByte(p, '\n')
+		line := p[0 : i+1]
+		p = p[i+1:]
+		// We prefixed each log line with a byte with the level.
+		level := Level(line[0])
+		line = line[1:]
+		var err error
+		if lw, ok := w.Writer.(LevelWriter); ok {
+			_, err = lw.WriteLevel(level, line)
+		} else {
+			_, err = w.Write(line)
+		}
+		if err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+// Trigger forces flushing the buffer and change the trigger state to
+// triggered, if the writer has not already been triggered before.
+func (w *TriggerLevelWriter) Trigger() error {
+	w.mu.Lock()
+	defer w.mu.Unlock()
+
+	return w.trigger()
+}
+
+// Close closes the writer and returns the buffer to the pool.
+func (w *TriggerLevelWriter) Close() error {
+	w.mu.Lock()
+	defer w.mu.Unlock()
+
+	if w.buf == nil {
+		return nil
+	}
+
+	// We return the buffer only if it has not grown above the limit.
+	// This prevents accumulation of large buffers in the pool just
+	// because occasionally a large buffer might be needed.
+	if w.buf.Cap() <= TriggerLevelWriterBufferReuseLimit {
+		w.buf.Reset()
+		triggerWriterPool.Put(w.buf)
+	}
+	w.buf = nil
+
+	return nil
+}

writer_test.go

@@ -1,9 +1,13 @@
-// +build !binary_log
-// +build !windows
+//go:build !binary_log && !windows
+// +build !binary_log,!windows
 
 package zerolog
 
 import (
+	"bytes"
+	"errors"
+	"fmt"
+	"io"
 	"reflect"
 	"testing"
 )
@@ -27,3 +31,222 @@ func TestMultiSyslogWriter(t *testing.T) {
 		t.Errorf("Invalid syslog message routing: want %v, got %v", want, got)
 	}
 }
+
+var writeCalls int
+
+type mockedWriter struct {
+	wantErr bool
+}
+
+func (c mockedWriter) Write(p []byte) (int, error) {
+	writeCalls++
+
+	if c.wantErr {
+		return -1, errors.New("Expected error")
+	}
+
+	return len(p), nil
+}
+
+// Tests that a new writer is only used if it actually works.
+func TestResilientMultiWriter(t *testing.T) {
+	tests := []struct {
+		name    string
+		writers []io.Writer
+	}{
+		{
+			name: "All valid writers",
+			writers: []io.Writer{
+				mockedWriter{
+					wantErr: false,
+				},
+				mockedWriter{
+					wantErr: false,
+				},
+			},
+		},
+		{
+			name: "All invalid writers",
+			writers: []io.Writer{
+				mockedWriter{
+					wantErr: true,
+				},
+				mockedWriter{
+					wantErr: true,
+				},
+			},
+		},
+		{
+			name: "First invalid writer",
+			writers: []io.Writer{
+				mockedWriter{
+					wantErr: true,
+				},
+				mockedWriter{
+					wantErr: false,
+				},
+			},
+		},
+		{
+			name: "First valid writer",
+			writers: []io.Writer{
+				mockedWriter{
+					wantErr: false,
+				},
+				mockedWriter{
+					wantErr: true,
+				},
+			},
+		},
+	}
+
+	for _, tt := range tests {
+		writers := tt.writers
+		multiWriter := MultiLevelWriter(writers...)
+
+		logger := New(multiWriter).With().Timestamp().Logger().Level(InfoLevel)
+		logger.Info().Msg("Test msg")
+
+		if len(writers) != writeCalls {
+			t.Errorf("Expected %d writers to have been called but only %d were.", len(writers), writeCalls)
+		}
+		writeCalls = 0
+	}
+}
+
+type testingLog struct {
+	testing.TB
+	buf bytes.Buffer
+}
+
+func (t *testingLog) Log(args ...interface{}) {
+	if _, err := t.buf.WriteString(fmt.Sprint(args...)); err != nil {
+		t.Error(err)
+	}
+}
+
+func (t *testingLog) Logf(format string, args ...interface{}) {
+	if _, err := t.buf.WriteString(fmt.Sprintf(format, args...)); err != nil {
+		t.Error(err)
+	}
+}
+
+func TestTestWriter(t *testing.T) {
+	tests := []struct {
+		name  string
+		write []byte
+		want  []byte
+	}{{
+		name:  "newline",
+		write: []byte("newline\n"),
+		want:  []byte("newline"),
+	}, {
+		name:  "oneline",
+		write: []byte("oneline"),
+		want:  []byte("oneline"),
+	}, {
+		name:  "twoline",
+		write: []byte("twoline\n\n"),
+		want:  []byte("twoline"),
+	}}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			tb := &testingLog{TB: t} // Capture TB log buffer.
+			w := TestWriter{T: tb}
+
+			n, err := w.Write(tt.write)
+			if err != nil {
+				t.Error(err)
+			}
+			if n != len(tt.write) {
+				t.Errorf("Expected %d write length but got %d", len(tt.write), n)
+			}
+			p := tb.buf.Bytes()
+			if !bytes.Equal(tt.want, p) {
+				t.Errorf("Expected %q, got %q.", tt.want, p)
+			}
+
+			log := New(NewConsoleWriter(ConsoleTestWriter(t)))
+			log.Info().Str("name", tt.name).Msg("Success!")
+
+			tb.buf.Reset()
+		})
+	}
+
+}
+
+func TestFilteredLevelWriter(t *testing.T) {
+	buf := bytes.Buffer{}
+	writer := FilteredLevelWriter{
+		Writer: LevelWriterAdapter{&buf},
+		Level:  InfoLevel,
+	}
+	_, err := writer.WriteLevel(DebugLevel, []byte("no"))
+	if err != nil {
+		t.Error(err)
+	}
+	_, err = writer.WriteLevel(InfoLevel, []byte("yes"))
+	if err != nil {
+		t.Error(err)
+	}
+	p := buf.Bytes()
+	if want := "yes"; !bytes.Equal([]byte(want), p) {
+		t.Errorf("Expected %q, got %q.", want, p)
+	}
+}
+
+type testWrite struct {
+	Level
+	Line []byte
+}
+
+func TestTriggerLevelWriter(t *testing.T) {
+	tests := []struct {
+		write []testWrite
+		want  []byte
+		all   []byte
+	}{{
+		[]testWrite{
+			{DebugLevel, []byte("no\n")},
+			{InfoLevel, []byte("yes\n")},
+		},
+		[]byte("yes\n"),
+		[]byte("yes\nno\n"),
+	}, {
+		[]testWrite{
+			{DebugLevel, []byte("yes1\n")},
+			{InfoLevel, []byte("yes2\n")},
+			{ErrorLevel, []byte("yes3\n")},
+			{DebugLevel, []byte("yes4\n")},
+		},
+		[]byte("yes2\nyes1\nyes3\nyes4\n"),
+		[]byte("yes2\nyes1\nyes3\nyes4\n"),
+	}}
+
+	for k, tt := range tests {
+		t.Run(fmt.Sprintf("case=%d", k), func(t *testing.T) {
+			buf := bytes.Buffer{}
+			writer := TriggerLevelWriter{Writer: LevelWriterAdapter{&buf}, ConditionalLevel: DebugLevel, TriggerLevel: ErrorLevel}
+			t.Cleanup(func() { writer.Close() })
+			for _, w := range tt.write {
+				_, err := writer.WriteLevel(w.Level, w.Line)
+				if err != nil {
+					t.Error(err)
+				}
+			}
+			p := buf.Bytes()
+			if want := tt.want; !bytes.Equal([]byte(want), p) {
+				t.Errorf("Expected %q, got %q.", want, p)
+			}
+			err := writer.Trigger()
+			if err != nil {
+				t.Error(err)
+			}
+			p = buf.Bytes()
+			if want := tt.all; !bytes.Equal([]byte(want), p) {
+				t.Errorf("Expected %q, got %q.", want, p)
+			}
+		})
+	}
+}