redis常规操作

	高并发的瓶颈就是数据库 笔记记录

下面是redis 的client 端操作，一般还可以和上篇map+lock 联合使用。都是帮助数据库减压的好手段.

//redis.go

var redisClient *redis.Client

func redisInit() {

	if redisClient == nil {
		redisClient = redis.NewClient(&redis.Options{
			Addr:     "127.0.0.1:6379",
			Password: "xxx",
			DB:       0,
		})
	}
}

//设置缓存如果是对象那转换成字符串
func Put(key string, obj interface{}) error {
	redisInit()
	value := obj
	val, err := json.Marshal(obj)
	if err == nil {
		value = string(val)
	} else {
		logs.Debug(err)
	}
	err = redisClient.Set(key, value, 0).Err()

	if err != nil {
		logs.Error("PutCache", key, err)
	}

	return nil
}

func PutStr(key string, data string) error {
	redisInit()

	err := redisClient.Set(key, data, 0).Err()
	if err != nil {
		logs.Error("PutCache", key, err)
	}

	return nil
}

//取键列表.
func KeyList(cursor uint64, pattern string, count int64) []string {
	redisInit()

keys, cur, err := redisClient.Scan(cursor, pattern, count).Result()
logs.Info(len(keys), cur, err)
return keys
}

//租约机制
func PutbyTime(key string, obj interface{}, timeout time.Duration) {
	redisInit()

	value := obj
	val, err := json.Marshal(obj)
	if err == nil {
		value = string(val)
	} else {
		return
	}

	err = redisClient.Set(key, value, timeout).Err()
	if err != nil {
		logs.Error("PutCache", key, err)
	}

}

//取字符串
func Get(key string) string {
	redisInit()
	val, err := redisClient.Get(key).Result()
	if err != nil {
		logs.Error("GetCache", key, err)
	}
	return val
}

//取结构对象
func GetObj(key string, retobj interface{}) error {
	redisInit()
	val, err := redisClient.Get(key).Result()
	if err != nil {
		logs.Error("GetCache", key, err)
		return err
	}
	json.Unmarshal([]byte(val), &retobj)

	return err
}

//清除all
func Clear() {
	redisInit()
	redisClient.FlushAll()
}

//删除
func Delete(key string) {
	redisInit()
	redisClient.Del(key)
}