💥 break: rename some interfaces and structs

- add func for quick cast Formatter

formatter.go

@@ -18,33 +18,49 @@ func (fn FormatterFunc) Format(r *Record) ([]byte, error) {
 	return fn(r)
 }
 
-// FormattableHandler interface
-type FormattableHandler interface {
+// Formattable interface
+type Formattable interface {
 	// Formatter get the log formatter
 	Formatter() Formatter
 	// SetFormatter set the log formatter
 	SetFormatter(Formatter)
 }
 
-// Formattable definition
-type Formattable struct {
+// FormattableTrait definition
+type FormattableTrait struct {
 	formatter Formatter
 }
 
 // Formatter get formatter. if not set, will return TextFormatter
-func (f *Formattable) Formatter() Formatter {
+func (f *FormattableTrait) Formatter() Formatter {
 	if f.formatter == nil {
 		f.formatter = NewTextFormatter()
 	}
 	return f.formatter
 }
 
 // SetFormatter to handler
-func (f *Formattable) SetFormatter(formatter Formatter) {
+func (f *FormattableTrait) SetFormatter(formatter Formatter) {
 	f.formatter = formatter
 }
 
 // Format log record to bytes
-func (f *Formattable) Format(record *Record) ([]byte, error) {
+func (f *FormattableTrait) Format(record *Record) ([]byte, error) {
 	return f.Formatter().Format(record)
 }
+
+// AsTextFormatter util func
+func AsTextFormatter(f Formatter) *TextFormatter {
+	if tf, ok := f.(*TextFormatter); ok {
+		return tf
+	}
+	panic("slog: cannot cast input as *TextFormatter")
+}
+
+// AsJSONFormatter util func
+func AsJSONFormatter(f Formatter) *JSONFormatter {
+	if jf, ok := f.(*JSONFormatter); ok {
+		return jf
+	}
+	panic("slog: cannot cast input as *JSONFormatter")
+}

formatter_json.go

@@ -45,7 +45,7 @@ type JSONFormatter struct {
 }
 
 // NewJSONFormatter create new JSONFormatter
-func NewJSONFormatter(fn ...func(*JSONFormatter)) *JSONFormatter {
+func NewJSONFormatter(fn ...func(f *JSONFormatter)) *JSONFormatter {
 	f := &JSONFormatter{
 		// Aliases: make(StringMap, 0),
 		Fields:     DefaultFields,

formatter_test.go

@@ -10,9 +10,25 @@ import (
 	"github.com/gookit/slog/handler"
 )
 
+func TestFormattableTrait_Formatter(t *testing.T) {
+	ft := &slog.FormattableTrait{}
+	tf := slog.AsTextFormatter(ft.Formatter())
+	assert.NotNil(t, tf)
+	assert.Panics(t, func() {
+		slog.AsJSONFormatter(ft.Formatter())
+	})
+
+	ft.SetFormatter(slog.NewJSONFormatter())
+	jf := slog.AsJSONFormatter(ft.Formatter())
+	assert.NotNil(t, jf)
+	assert.Panics(t, func() {
+		slog.AsTextFormatter(ft.Formatter())
+	})
+}
+
 func TestFormattable_Format(t *testing.T) {
 	r := newLogRecord("TEST_LOG_MESSAGE format")
-	f := &slog.Formattable{}
+	f := &slog.FormattableTrait{}
 	assert.Eq(t, "slog: TEST_LOG_MESSAGE format", r.GoString())
 
 	bts, err := f.Format(r)

handler.go

@@ -25,10 +25,16 @@ type Handler interface {
 
 // LevelFormattable support limit log levels and provide formatter
 type LevelFormattable interface {
-	FormattableHandler
+	Formattable
 	IsHandling(level Level) bool
 }
 
+// FormattableHandler interface
+type FormattableHandler interface {
+	Handler
+	Formattable
+}
+
 /********************************************************************************
  * Common parts for handler
  ********************************************************************************/
@@ -38,7 +44,7 @@ type LevelFormattable interface {
 // - support set log formatter
 // - only support set one log level
 type LevelWithFormatter struct {
-	Formattable
+	FormattableTrait
 	// Level for log message. if current level >= Level will log message
 	Level Level
 }
@@ -58,7 +64,7 @@ func (h *LevelWithFormatter) IsHandling(level Level) bool {
 // - support set log formatter
 // - support setting multi log levels
 type LevelsWithFormatter struct {
-	Formattable
+	FormattableTrait
 	// Levels for log message
 	Levels []Level
 }

handler/builder.go

@@ -106,7 +106,7 @@ func (b *Builder) WithUseJSON(useJSON bool) *Builder {
 }
 
 // Build slog handler.
-func (b *Builder) Build() slog.Handler {
+func (b *Builder) Build() slog.FormattableHandler {
 	if b.Output != nil {
 		return b.buildFromWriter(b.Output)
 	}
@@ -119,17 +119,11 @@ func (b *Builder) Build() slog.Handler {
 		return b.buildFromWriter(w)
 	}
 
-	panic("missing some information for build slog handler")
+	panic("slog: missing information for build slog handler")
 }
 
 // Build slog handler.
-func (b *Builder) reset() {
-	b.Output = nil
-	b.Config = NewEmptyConfig()
-}
-
-// Build slog handler.
-func (b *Builder) buildFromWriter(w io.Writer) (h slog.Handler) {
+func (b *Builder) buildFromWriter(w io.Writer) (h slog.FormattableHandler) {
 	defer b.reset()
 	bufSize := b.BuffSize
 	lf := b.newLevelFormattable()
@@ -178,14 +172,13 @@ func (b *Builder) buildFromWriter(w io.Writer) (h slog.Handler) {
 
 	// use json format.
 	if b.UseJSON {
-		type formatterSetter interface {
-			SetFormatter(slog.Formatter)
-		}
-
-		// has setter
-		if _, ok := h.(formatterSetter); ok {
-			h.(formatterSetter).SetFormatter(slog.NewJSONFormatter())
-		}
+		h.SetFormatter(slog.NewJSONFormatter())
 	}
 	return
 }
+
+// rest builder.
+func (b *Builder) reset() {
+	b.Output = nil
+	b.Config = NewEmptyConfig()
+}

handler/handler.go

@@ -57,7 +57,7 @@ type SyncCloseWriter interface {
 //
 // Deprecated: please use slog.LevelWithFormatter instead.
 type LevelWithFormatter struct {
-	slog.Formattable
+	slog.FormattableTrait
 	// Level for log message. if current level <= Level will log message
 	Level slog.Level
 }
@@ -74,7 +74,7 @@ func (h *LevelWithFormatter) IsHandling(level slog.Level) bool {
 //
 // Deprecated: please use slog.LevelsWithFormatter instead.
 type LevelsWithFormatter struct {
-	slog.Formattable
+	slog.FormattableTrait
 	// Levels for log message
 	Levels []slog.Level
 }