diff --git a/types/lib.go b/types/lib.go
index c6765ca..6262908 100644
--- a/types/lib.go
+++ b/types/lib.go
@@ -228,6 +228,11 @@ func (l *Log) AddHistory(s string) {
 	}
 }
 
+func (l *Log) Printf(s string, i ...interface{}) {
+	l.AddHistory(fmt.Sprintf(s, i...))
+	s = fmt.Sprintf("* %s: %s", time.Now().Format("02/01/06 - 15:04:05"), s)
+}
+
 type LogQuery struct {
 	From  time.Time `json:"from"`
 	Until time.Time `json:"until"`