Add TextFormatter config for custom quote runes

text_formatter.go

@@ -7,6 +7,7 @@ import (
 	"strings"
 	"sync"
 	"time"
+	"unicode/utf8"
 )
 
 const (
@@ -52,9 +53,13 @@ type TextFormatter struct {
 	// QuoteEmptyFields will wrap empty fields in quotes if true
 	QuoteEmptyFields bool
 
+	// QuoteRune can be set to override the default quote style
+	QuoteRune rune
+
 	// Whether the logger's out is to a terminal
 	isTerminal bool
-	terminalOnce sync.Once
+
+	sync.Once
 }
 
 func (f *TextFormatter) Format(entry *Entry) ([]byte, error) {
@@ -75,7 +80,10 @@ func (f *TextFormatter) Format(entry *Entry) ([]byte, error) {
 
 	prefixFieldClashes(entry.Data)
 
-	f.terminalOnce.Do(func() {
+	f.Do(func() {
+		if f.QuoteRune == 0 || !utf8.ValidRune(f.QuoteRune) {
+			f.QuoteRune = '"'
+		}
 		if entry.Logger != nil {
 			f.isTerminal = IsTerminal(entry.Logger.Out)
 		}
@@ -164,14 +172,14 @@ func (f *TextFormatter) appendValue(b *bytes.Buffer, value interface{}) {
 		if !f.needsQuoting(value) {
 			b.WriteString(value)
 		} else {
-			fmt.Fprintf(b, "%q", value)
+			fmt.Fprintf(b, "%c%v%c", f.QuoteRune, value, f.QuoteRune)
 		}
 	case error:
 		errmsg := value.Error()
 		if !f.needsQuoting(errmsg) {
 			b.WriteString(errmsg)
 		} else {
-			fmt.Fprintf(b, "%q", errmsg)
+			fmt.Fprintf(b, "%c%v%c", f.QuoteRune, errmsg, f.QuoteRune)
 		}
 	default:
 		fmt.Fprint(b, value)

text_formatter_test.go

@@ -14,7 +14,7 @@ func TestQuoting(t *testing.T) {
 	checkQuoting := func(q bool, value interface{}) {
 		b, _ := tf.Format(WithField("test", value))
 		idx := bytes.Index(b, ([]byte)("test="))
-		cont := bytes.Contains(b[idx+5:], []byte{'"'})
+		cont := bytes.ContainsRune(b[idx+5:], tf.QuoteRune)
 		if cont != q {
 			if q {
 				t.Errorf("quoting expected for: %#v", value)
@@ -34,6 +34,14 @@ func TestQuoting(t *testing.T) {
 	checkQuoting(false, errors.New("invalid"))
 	checkQuoting(true, errors.New("invalid argument"))
 
+	// Test for custom quote rune.
+	tf.QuoteRune = '`'
+	checkQuoting(false, "")
+	checkQuoting(false, "abcd")
+	checkQuoting(true, "/foobar")
+	checkQuoting(true, errors.New("invalid argument"))
+
+	// Test for quoting empty fields.
 	tf.QuoteEmptyFields = true
 	checkQuoting(true, "")
 }
@@ -45,7 +53,8 @@ func TestTimestampFormat(t *testing.T) {
 		timeStart := bytes.Index(customStr, ([]byte)("time="))
 		timeEnd := bytes.Index(customStr, ([]byte)("level="))
 		timeStr := customStr[timeStart+5 : timeEnd-1]
-		if timeStr[0] == '"' && timeStr[len(timeStr)-1] == '"' {
+		if timeStr[0] == byte(customFormatter.QuoteRune) &&
+			timeStr[len(timeStr)-1] == byte(customFormatter.QuoteRune) {
 			timeStr = timeStr[1 : len(timeStr)-1]
 		}
 		if format == "" {