Allow log prefix

logs/log.go

@@ -47,7 +47,7 @@ import (
 
 // RFC5424 log message levels.
 const (
-	LevelEmergency = iota
+	LevelEmergency     = iota
 	LevelAlert
 	LevelCritical
 	LevelError
@@ -116,6 +116,7 @@ type BeeLogger struct {
 	enableFuncCallDepth bool
 	loggerFuncCallDepth int
 	asynchronous        bool
+	prefix              string
 	msgChanLen          int64
 	msgChan             chan *logMsg
 	signalChan          chan string
@@ -247,7 +248,7 @@ func (bl *BeeLogger) Write(p []byte) (n int, err error) {
 	}
 	// writeMsg will always add a '\n' character
 	if p[len(p)-1] == '\n' {
-		p = p[0 : len(p)-1]
+		p = p[0: len(p)-1]
 	}
 	// set levelLoggerImpl to ensure all log message will be write out
 	err = bl.writeMsg(levelLoggerImpl, string(p))
@@ -267,6 +268,9 @@ func (bl *BeeLogger) writeMsg(logLevel int, msg string, v ...interface{}) error
 	if len(v) > 0 {
 		msg = fmt.Sprintf(msg, v...)
 	}
+
+	msg = bl.prefix + " " + msg
+
 	when := time.Now()
 	if bl.enableFuncCallDepth {
 		_, file, line, ok := runtime.Caller(bl.loggerFuncCallDepth)
@@ -320,6 +324,11 @@ func (bl *BeeLogger) EnableFuncCallDepth(b bool) {
 	bl.enableFuncCallDepth = b
 }
 
+// set prefix
+func (bl *BeeLogger) SetPrefix(s string) {
+	bl.prefix = s
+}
+
 // start logger chan reading.
 // when chan is not empty, write logs.
 func (bl *BeeLogger) startLogger() {
@@ -544,6 +553,11 @@ func SetLevel(l int) {
 	beeLogger.SetLevel(l)
 }
 
+// SetPrefix sets the prefix
+func SetPrefix(s string) {
+	beeLogger.SetPrefix(s)
+}
+
 // EnableFuncCallDepth enable log funcCallDepth
 func EnableFuncCallDepth(b bool) {
 	beeLogger.enableFuncCallDepth = b