Merge branch 'master' into caller_feature

json_formatter.go

@@ -1,6 +1,7 @@
 package logrus
 
 import (
+	"bytes"
 	"encoding/json"
 	"fmt"
 )
@@ -10,14 +11,6 @@ type fieldKey string
 // FieldMap allows customization of the key names for default fields.
 type FieldMap map[fieldKey]string
 
-// Default key names for the default fields
-const (
-	FieldKeyMsg   = "msg"
-	FieldKeyLevel = "level"
-	FieldKeyTime  = "time"
-	FieldKeyFunc  = "func"
-)
-
 func (f FieldMap) resolve(key fieldKey) string {
 	if k, ok := f[key]; ok {
 		return k
@@ -34,6 +27,9 @@ type JSONFormatter struct {
 	// DisableTimestamp allows disabling automatic timestamps in output
 	DisableTimestamp bool
 
+	// DataKey allows users to put all the log entry parameters into a nested dictionary at a given key.
+	DataKey string
+
 	// FieldMap allows users to customize the names of keys for default fields.
 	// As an example:
 	// formatter := &JSONFormatter{
@@ -42,11 +38,12 @@ type JSONFormatter struct {
 	// 		 FieldKeyLevel: "@level",
 	// 		 FieldKeyMsg:   "@message",
 	// 		 FieldKeyFunc:  "@caller",
-	// 		 FieldKeyMsg:   "@message",
-	// 		 FieldKeyFunc:  "@caller",
 	//    },
 	// }
 	FieldMap FieldMap
+
+	// PrettyPrint will indent all json logs
+	PrettyPrint bool
 }
 
 // Format renders a single log entry
@@ -63,13 +60,22 @@ func (f *JSONFormatter) Format(entry *Entry) ([]byte, error) {
 		}
 	}
 
-	prefixFieldClashes(data, entry.HasCaller())
+	if f.DataKey != "" {
+		newData := make(Fields, 4)
+		newData[f.DataKey] = data
+		data = newData
+	}
+
+	prefixFieldClashes(data, f.FieldMap, entry.HasCaller())
 
 	timestampFormat := f.TimestampFormat
 	if timestampFormat == "" {
 		timestampFormat = defaultTimestampFormat
 	}
 
+	if entry.err != "" {
+		data[f.FieldMap.resolve(FieldKeyLogrusError)] = entry.err
+	}
 	if !f.DisableTimestamp {
 		data[f.FieldMap.resolve(FieldKeyTime)] = entry.Time.Format(timestampFormat)
 	}
@@ -78,9 +84,21 @@ func (f *JSONFormatter) Format(entry *Entry) ([]byte, error) {
 	if entry.HasCaller() {
 		data[f.FieldMap.resolve(FieldKeyFunc)] = entry.Caller
 	}
-	serialized, err := json.Marshal(data)
-	if err != nil {
+
+	var b *bytes.Buffer
+	if entry.Buffer != nil {
+		b = entry.Buffer
+	} else {
+		b = &bytes.Buffer{}
+	}
+
+	encoder := json.NewEncoder(b)
+	if f.PrettyPrint {
+		encoder.SetIndent("", "  ")
+	}
+	if err := encoder.Encode(data); err != nil {
 		return nil, fmt.Errorf("Failed to marshal fields to JSON, %v", err)
 	}
-	return append(serialized, '\n'), nil
+
+	return b.Bytes(), nil
 }