Redis Monitor Script that only log command

redmon.go

package main

import (
	"flag"
	"fmt"
	"log"
	"os"
	"strings"
	"time"

	"github.com/xuyu/goredis"
)

func main() {
	var address string
	var excluded string
	// Redis Staging "redis-staging.redis.singapore.rds.aliyuncs.com:6379"
	flag.StringVar(&address, "redis", "10.255.13.0:6379", "redis address+port DEFAULT:10.255.13.0:6379")
	flag.StringVar(&excluded, "excluded", "GET PING", "excluded commands DEFAULT: GET PING")
	flag.Parse()

	// Data Logger (Filtered)
	dataFile, err := os.OpenFile("data.log", os.O_APPEND|os.O_CREATE|os.O_WRONLY, 0644)
	if err != nil {
		log.Println(err)
	}
	defer dataFile.Close()

	timeout := 10
	maxIdle := 1
	cfg := goredis.DialConfig{
		Address: address,
		Timeout: time.Duration(timeout) * time.Second,
		MaxIdle: maxIdle,
	}
	redis, err := goredis.Dial(&cfg)
	if err != nil {
		log.Fatal("Cannot Init Connection to redis error:", err)
	}
	log.Println("Init connection successfully")

	mon, err := redis.Monitor()
	if err != nil {
		log.Fatal("Cannot Start Monitor command error:", err)
	}
	log.Println("Start monitoring")
	defer mon.Close()
	var i = 0
	for {
		if s, err := mon.Receive(); err != nil {
			log.Println(err)
		} else if s == "" {
			log.Println()
		} else {
			pos := strings.Index(s, "]")
			ent := s[pos+1 : len(s)]
			if len(ent) > 0 {
				cmd := strings.Fields(ent)[0]
				isExcluded := false
				for _, ex := range strings.Fields(excluded) {
					if strings.EqualFold(cmd, "\""+ex+"\"") {
						isExcluded = true
						break
					}
				}
				if !isExcluded {
					i++
					dataFile.WriteString(fmt.Sprintf("[%d]%s\n", i, ent))
					log.Println(ent)
				}
			}
		}
	}
}