diff --git a/log/helper.go b/log/helper.go
index 6af7f09b8..b01c947ac 100644
--- a/log/helper.go
+++ b/log/helper.go
@@ -6,6 +6,7 @@ import (
 	"os"
 )
 
+// DefaultMessageKey default message key.
 var DefaultMessageKey = "msg"
 
 // Option is Helper option.
@@ -17,6 +18,7 @@ type Helper struct {
 	msgKey string
 }
 
+// WithMessageKey with message key.
 func WithMessageKey(k string) Option {
 	return func(opts *Helper) {
 		opts.msgKey = k
@@ -51,78 +53,78 @@ func (h *Helper) Log(level Level, keyvals ...interface{}) {
 
 // Debug logs a message at debug level.
 func (h *Helper) Debug(a ...interface{}) {
-	h.Log(LevelDebug, h.msgKey, fmt.Sprint(a...))
+	_ = h.logger.Log(LevelDebug, h.msgKey, fmt.Sprint(a...))
 }
 
 // Debugf logs a message at debug level.
 func (h *Helper) Debugf(format string, a ...interface{}) {
-	h.Log(LevelDebug, h.msgKey, fmt.Sprintf(format, a...))
+	_ = h.logger.Log(LevelDebug, h.msgKey, fmt.Sprintf(format, a...))
 }
 
 // Debugw logs a message at debug level.
 func (h *Helper) Debugw(keyvals ...interface{}) {
-	h.Log(LevelDebug, keyvals...)
+	_ = h.logger.Log(LevelDebug, keyvals...)
 }
 
 // Info logs a message at info level.
 func (h *Helper) Info(a ...interface{}) {
-	h.Log(LevelInfo, h.msgKey, fmt.Sprint(a...))
+	_ = h.logger.Log(LevelInfo, h.msgKey, fmt.Sprint(a...))
 }
 
 // Infof logs a message at info level.
 func (h *Helper) Infof(format string, a ...interface{}) {
-	h.Log(LevelInfo, h.msgKey, fmt.Sprintf(format, a...))
+	_ = h.logger.Log(LevelInfo, h.msgKey, fmt.Sprintf(format, a...))
 }
 
 // Infow logs a message at info level.
 func (h *Helper) Infow(keyvals ...interface{}) {
-	h.Log(LevelInfo, keyvals...)
+	_ = h.logger.Log(LevelInfo, keyvals...)
 }
 
 // Warn logs a message at warn level.
 func (h *Helper) Warn(a ...interface{}) {
-	h.Log(LevelWarn, h.msgKey, fmt.Sprint(a...))
+	_ = h.logger.Log(LevelWarn, h.msgKey, fmt.Sprint(a...))
 }
 
 // Warnf logs a message at warnf level.
 func (h *Helper) Warnf(format string, a ...interface{}) {
-	h.Log(LevelWarn, h.msgKey, fmt.Sprintf(format, a...))
+	_ = h.logger.Log(LevelWarn, h.msgKey, fmt.Sprintf(format, a...))
 }
 
 // Warnw logs a message at warnf level.
 func (h *Helper) Warnw(keyvals ...interface{}) {
-	h.Log(LevelWarn, keyvals...)
+	_ = h.logger.Log(LevelWarn, keyvals...)
 }
 
 // Error logs a message at error level.
 func (h *Helper) Error(a ...interface{}) {
-	h.Log(LevelError, h.msgKey, fmt.Sprint(a...))
+	_ = h.logger.Log(LevelError, h.msgKey, fmt.Sprint(a...))
 }
 
 // Errorf logs a message at error level.
 func (h *Helper) Errorf(format string, a ...interface{}) {
-	h.Log(LevelError, h.msgKey, fmt.Sprintf(format, a...))
+	_ = h.logger.Log(LevelError, h.msgKey, fmt.Sprintf(format, a...))
 }
 
 // Errorw logs a message at error level.
 func (h *Helper) Errorw(keyvals ...interface{}) {
-	h.Log(LevelError, keyvals...)
+	_ = h.logger.Log(LevelError, keyvals...)
 }
 
 // Fatal logs a message at fatal level.
 func (h *Helper) Fatal(a ...interface{}) {
-	h.Log(LevelFatal, h.msgKey, fmt.Sprint(a...))
+	_ = h.logger.Log(LevelFatal, h.msgKey, fmt.Sprint(a...))
 	os.Exit(1)
 }
 
 // Fatalf logs a message at fatal level.
 func (h *Helper) Fatalf(format string, a ...interface{}) {
-	h.Log(LevelFatal, h.msgKey, fmt.Sprintf(format, a...))
+	_ = h.logger.Log(LevelFatal, h.msgKey, fmt.Sprintf(format, a...))
 	os.Exit(1)
 }
 
 // Fatalw logs a message at fatal level.
 func (h *Helper) Fatalw(keyvals ...interface{}) {
-	h.Log(LevelFatal, keyvals...)
+	_ = h.logger.Log(LevelFatal, keyvals...)
 	os.Exit(1)
 }