Simple Tee writer

tee.go

type TeeWriter struct {
	w []io.Writer
}

func (t TeeWriter) Write(p []byte) (n int, err error) {
	for _, writer := range t.w {
		n, err = writer.Write(p)
		if err != nil {
			return n, err
		}
	}
	return
}

Usage:

Logger.SetOutput(TeeWriter{[]io.Writer{
	os.Stdout, &lumberjack.Logger{
		Filename:   "/tmp/myapp.log",
		MaxSize:    500,
		MaxBackups: 3,
		MaxAge:     28,
		Compress:   true,
	},
}})