Add dict support

README.md

@@ -96,9 +96,21 @@ if e := log.Debug(); e.Enabled() {
     e.Str("foo": value).Msg("some debug message")
 }
 
-// Output: {"level":"info","time":1494567715,"routed message"}
+// Output: {"level":"info","time":1494567715,"message":"routed message"}
 ```
 
+### Sub dictionary
+
+```go
+log.Info().
+    Str("foo", "bar").
+    Dict("dict", zerolog.Dict().
+        Str("bar", "baz").
+        Int("n", 1)
+    ).Msg("hello world")
+
+// Output: {"level":"info","time":1494567715,"foo":"bar","dict":{"bar":"baz","n":1},"message":"hello world"}
+```
 
 ### Customize automatic field names
 

context.go

@@ -25,6 +25,12 @@ func (c Context) append(f field) Context {
 	}
 }
 
+// Dict adds the field key with the dict to the logger context.
+func (c Context) Dict(key string, dict Event) Context {
+	dict.buf.WriteByte('}')
+	return c.append(fRaw(key, dict.buf.String()))
+}
+
 // Str adds the field key with val as a string to the logger context.
 func (c Context) Str(key, val string) Context {
 	return c.append(fStr(key, val))

event.go

@@ -3,6 +3,8 @@ package zerolog
 import (
 	"bytes"
 	"fmt"
+	"io"
+	"io/ioutil"
 	"sync"
 	"time"
 )
@@ -101,6 +103,27 @@ func (e Event) Msgf(format string, v ...interface{}) (n int, err error) {
 	return e.write()
 }
 
+// Dict adds the field key with a dict to the event context.
+// Use zerolog.Dict() to create the dictionary.
+func (e Event) Dict(key string, dict Event) Event {
+	if !e.enabled {
+		return e
+	}
+	if e.buf.Len() > 1 {
+		e.buf.WriteByte(',')
+	}
+	io.Copy(e.buf, dict.buf)
+	e.buf.WriteByte('}')
+	return e
+}
+
+// Dict creates an Event to be used with the event.Dict method.
+// Call usual field methods like Str, Int etc to add fields to this
+// event and give it as argument the event.Dict method.
+func Dict() Event {
+	return newEvent(levelWriterAdapter{ioutil.Discard}, 0, true)
+}
+
 // Str adds the field key with val as a string to the event context.
 func (e Event) Str(key, val string) Event {
 	if !e.enabled {

field.go

@@ -134,5 +134,8 @@ func fTimestamp() field {
 
 func fTime(key string, t time.Time) field {
 	return field{key, quotedFieldMode, t.Format(TimeFieldFormat), nil}
-
+}
+
+func fRaw(key string, raw string) field {
+	return field{key, rawFieldMode, raw, nil}
 }

log_example_test.go

@@ -99,3 +99,30 @@ func ExampleLogger_Log() {
 
 	// Output: {"foo":"bar","bar":"baz"}
 }
+
+func ExampleEvent_Dict() {
+	log := zerolog.New(os.Stdout)
+
+	log.Log().
+		Str("foo", "bar").
+		Dict("dict", zerolog.Dict().
+			Str("bar", "baz").
+			Int("n", 1),
+		).
+		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").
+		Dict("dict", zerolog.Dict().
+			Str("bar", "baz").
+			Int("n", 1),
+		).Logger()
+
+	log.Log().Msg("hello world")
+
+	// Output: {"foo":"bar","dict":{"bar":"baz","n":1},"message":"hello world"}
+}

log_test.go

@@ -87,7 +87,7 @@ func TestWith(t *testing.T) {
 		Uint8("uint8", 7).
 		Uint16("uint16", 8).
 		Uint32("uint32", 9).
-		Uint32("uint64", 10).
+		Uint64("uint64", 10).
 		Float32("float32", 11).
 		Float64("float64", 12).
 		Time("time", time.Time{}).
@@ -114,7 +114,7 @@ func TestFields(t *testing.T) {
 		Uint8("uint8", 7).
 		Uint16("uint16", 8).
 		Uint32("uint32", 9).
-		Uint32("uint64", 10).
+		Uint64("uint64", 10).
 		Float32("float32", 11).
 		Float64("float64", 12).
 		Time("time", time.Time{}).
@@ -140,7 +140,7 @@ func TestFieldsDisabled(t *testing.T) {
 		Uint8("uint8", 7).
 		Uint16("uint16", 8).
 		Uint32("uint32", 9).
-		Uint32("uint64", 10).
+		Uint64("uint64", 10).
 		Float32("float32", 11).
 		Float64("float64", 12).
 		Time("time", time.Time{}).