Added support for providing custom logger name encoders

zapcore/console_encoder.go

@@ -80,7 +80,15 @@ func (c consoleEncoder) EncodeEntry(ent Entry, fields []Field) (*buffer.Buffer,
 		c.EncodeLevel(ent.Level, arr)
 	}
 	if ent.LoggerName != "" && c.NameKey != "" {
-		arr.AppendString(ent.LoggerName)
+		nameEncoder := c.EncodeName
+
+		// if no name encoder provided, fall back to FullNameEncoder for backwards
+		// compatibility
+		if nameEncoder == nil {
+			nameEncoder = FullNameEncoder
+		}
+
+		nameEncoder(ent.LoggerName, arr)
 	}
 	if ent.Caller.Defined && c.CallerKey != "" && c.EncodeCaller != nil {
 		c.EncodeCaller(ent.Caller, arr)

zapcore/encoder.go

@@ -196,6 +196,24 @@ func (e *CallerEncoder) UnmarshalText(text []byte) error {
 	return nil
 }
 
+// A NameEncoder serializes a LoggerName to a primitive type.
+type NameEncoder func(string, PrimitiveArrayEncoder)
+
+// FullNameEncoder serializes a logger name as is
+func FullNameEncoder(loggerName string, enc PrimitiveArrayEncoder) {
+	enc.AppendString(loggerName)
+}
+
+// UnmarshalText unmarshals text to a NameEncoder. everything is unmarshaled to
+// FullNameEncoder.
+func (e *NameEncoder) UnmarshalText(text []byte) error {
+	switch string(text) {
+	default:
+		*e = FullNameEncoder
+	}
+	return nil
+}
+
 // An EncoderConfig allows users to configure the concrete encoders supplied by
 // zapcore.
 type EncoderConfig struct {
@@ -210,11 +228,14 @@ type EncoderConfig struct {
 	LineEnding    string `json:"lineEnding" yaml:"lineEnding"`
 	// Configure the primitive representations of common complex types. For
 	// example, some users may want all time.Times serialized as floating-point
-	// seconds since epoch, while others may prefer ISO8601 strings.
+	// seconds since epoch, while others may prefer ISO8601 strings. EncodeName
+	// is optional - initializing it to nil will fall back to printing the logger
+	// name as is (using FullNameEncoder)
 	EncodeLevel    LevelEncoder    `json:"levelEncoder" yaml:"levelEncoder"`
 	EncodeTime     TimeEncoder     `json:"timeEncoder" yaml:"timeEncoder"`
 	EncodeDuration DurationEncoder `json:"durationEncoder" yaml:"durationEncoder"`
 	EncodeCaller   CallerEncoder   `json:"callerEncoder" yaml:"callerEncoder"`
+	EncodeName     NameEncoder     `json:"nameEncoder" yaml:"nameEncoder"`
 }
 
 // ObjectEncoder is a strongly-typed, encoding-agnostic interface for adding a

zapcore/encoder_test.go

@@ -21,6 +21,7 @@
 package zapcore_test
 
 import (
+	"strings"
 	"testing"
 	"time"
 
@@ -74,6 +75,11 @@ func withConsoleEncoder(f func(Encoder)) {
 	f(NewConsoleEncoder(humanEncoderConfig()))
 }
 
+// capitalNameEncoder serializes a logger name in all caps
+func capitalNameEncoder(loggerName string, enc PrimitiveArrayEncoder) {
+	enc.AppendString(strings.ToUpper(loggerName))
+}
+
 func TestEncoderConfiguration(t *testing.T) {
 	base := testEncoderConfig()
 
@@ -293,6 +299,25 @@ func TestEncoderConfiguration(t *testing.T) {
 			expectedJSON:    `{"L":"INFO","T":0,"N":"main","C":"foo.go:42","M":"hello","S":"fake-stack"}` + "\n",
 			expectedConsole: "0\tINFO\tmain\tfoo.go:42\thello\nfake-stack\n",
 		},
+		{
+			desc: "use the supplied EncodeName",
+			cfg: EncoderConfig{
+				LevelKey:       "L",
+				TimeKey:        "T",
+				MessageKey:     "M",
+				NameKey:        "N",
+				CallerKey:      "C",
+				StacktraceKey:  "S",
+				LineEnding:     base.LineEnding,
+				EncodeTime:     base.EncodeTime,
+				EncodeDuration: base.EncodeDuration,
+				EncodeLevel:    base.EncodeLevel,
+				EncodeCaller:   base.EncodeCaller,
+				EncodeName:     capitalNameEncoder,
+			},
+			expectedJSON:    `{"L":"info","T":0,"N":"MAIN","C":"foo.go:42","M":"hello","S":"fake-stack"}` + "\n",
+			expectedConsole: "0\tinfo\tMAIN\tfoo.go:42\thello\nfake-stack\n",
+		},
 		{
 			desc: "close all open namespaces",
 			cfg: EncoderConfig{
@@ -393,6 +418,25 @@ func TestEncoderConfiguration(t *testing.T) {
 			expectedJSON:    `{"L":"info","T":0,"N":"main","C":"foo.go:42","M":"hello","S":"fake-stack"}` + "\n",
 			expectedConsole: "0\tinfo\tmain\thello\nfake-stack\n",
 		},
+		{
+			desc: "handle no-op EncodeName",
+			cfg: EncoderConfig{
+				LevelKey:       "L",
+				TimeKey:        "T",
+				MessageKey:     "M",
+				NameKey:        "N",
+				CallerKey:      "C",
+				StacktraceKey:  "S",
+				LineEnding:     base.LineEnding,
+				EncodeTime:     base.EncodeTime,
+				EncodeDuration: base.EncodeDuration,
+				EncodeLevel:    base.EncodeLevel,
+				EncodeCaller:   base.EncodeCaller,
+				EncodeName:     func(string, PrimitiveArrayEncoder) {},
+			},
+			expectedJSON:    `{"L":"info","T":0,"N":"main","C":"foo.go:42","M":"hello","S":"fake-stack"}` + "\n",
+			expectedConsole: "0\tinfo\tfoo.go:42\thello\nfake-stack\n",
+		},
 		{
 			desc: "use custom line separator",
 			cfg: EncoderConfig{
@@ -559,6 +603,27 @@ func TestCallerEncoders(t *testing.T) {
 	}
 }
 
+func TestNameEncoders(t *testing.T) {
+	tests := []struct {
+		name     string
+		expected interface{} // output of encoding InfoLevel
+	}{
+		{"", "main"},
+		{"something-random", "main"},
+	}
+
+	for _, tt := range tests {
+		var ne NameEncoder
+		require.NoError(t, ne.UnmarshalText([]byte(tt.name)), "Unexpected error unmarshaling %q.", tt.name)
+		assertAppended(
+			t,
+			tt.expected,
+			func(arr ArrayEncoder) { ne("main", arr) },
+			"Unexpected output serializing logger name with %q.", tt.name,
+		)
+	}
+}
+
 func assertAppended(t testing.TB, expected interface{}, f func(ArrayEncoder), msgAndArgs ...interface{}) {
 	mem := NewMapObjectEncoder()
 	mem.AddArray("k", ArrayMarshalerFunc(func(arr ArrayEncoder) error {

zapcore/json_encoder.go

@@ -302,7 +302,21 @@ func (enc *jsonEncoder) EncodeEntry(ent Entry, fields []Field) (*buffer.Buffer,
 	}
 	if ent.LoggerName != "" && final.NameKey != "" {
 		final.addKey(final.NameKey)
-		final.AppendString(ent.LoggerName)
+		cur := final.buf.Len()
+		nameEncoder := final.EncodeName
+
+		// if no name encoder provided, fall back to FullNameEncoder for backwards
+		// compatibility
+		if nameEncoder == nil {
+			nameEncoder = FullNameEncoder
+		}
+
+		nameEncoder(ent.LoggerName, final)
+		if cur == final.buf.Len() {
+			// User-supplied EncodeName was a no-op. Fall back to strings to
+			// keep output JSON valid.
+			final.AppendString(ent.LoggerName)
+		}
 	}
 	if ent.Caller.Defined && final.CallerKey != "" {
 		final.addKey(final.CallerKey)