Getting error message about command name when making rpop sometimes

[edwvee]

Version:

github.com/redis/go-redis/v9 v9.7.0

I'm connect:

redis := redis.NewClient(&redis.Options{
		Network:         settings.RedisNetwork,
		Addr:            settings.RedisAddr,
		Password:        settings.RedisPassword,
		DB:              0,
		MaxActiveConns:  10,
		MaxIdleConns:    1,
		ConnMaxLifetime: time.Minute,
	})
defer redis.Close()
	_, err := redis.Ping(ctx).Result()
	if err != nil {
		log.Fatalf("Error connecting redis: %s", err.Error())
	}

Then I use redis in my daemon all it's lifetime:

res, err := redis.RPop(ctx, key).Result()
if err != nil{
    panic(err)
}

I don't have any other usage of Redis.
So it works for days perfectly, but then I get next error:

ERR Syntax error, try CLIENT (LIST | KILL | GETNAME | SETNAME | PAUSE | REPLY)

I don't know if it's a bug in my version of redis or a bug in the library. For me it looks like I call "rpop my_key", redis answers "I don't know your command". Help me, please.

[ndyakov]

Hello @edwvee , can you share more information about the version of redis you are using? Also I assume there is another command that is being executed by the client. How are you initializing the client and the connection?

[edwvee]

Hello @edwvee , can you share more information about the version of redis you are using? Also I assume there is another command that is being executed by the client. How are you initializing the client and the connection?

redis_version:3.2.12

Updated the connection code. The usage code (I know not the best one) is almost identical to this:

func (r *Repository) GetVal(ctx context.Context) (string, error) {
	val, err := r.redis.RPop(ctx, "key_1").Result()
	if err != nil {
		if err == redis.Nil {
			val, err := r.redis.RPop(ctx, "key_2").Result()
			if err != nil {
				if err == redis.Nil {
					return "", err
				}
				if strings.Contains(err.Error(), "imeout") {
					time.Sleep(time.Second * 10)
					return r.GetVal(ctx)
				}
				panic(err)
			} else {
				return val, err
			}
		}
		if strings.Contains(err.Error(), "imeout") {
			time.Sleep(time.Second * 10)
			return r.GetVal(ctx)
		}
		panic(err)
	}

	return val, err
}

It panics at the last panic call. This code could be called simultaneously in up to 10 goroutines. No other usage of redis in the application.

[edwvee]

if strings.Contains(err.Error(), "imeout") {
			time.Sleep(time.Second * 10)
			return r.GetVal(ctx)
		}

Well, need to explain this parts. I'm getting sometimes errors mentioning some kind of timeout. That is strange for a simple rpop and for the key contains list with short strings. So I just wait in case there is something wrong with the redis instance and try again.
The passed context is without deadline.

[ndyakov]

@edwvee I think the error you are getting is because you are using older version of redis that does not support CLIENT SETINFO. The go-redis client will try to set its library information as part of the handshake for the connection. You can disable this by using https://github.com/redis/go-redis?tab=readme-ov-file#disabling-identity-verification
I would advice you to update your redis to a newer version and update the client to the latest release (see the note about the typo in the option).

Let me know if this helps. If your problem is resolved, please close this issue.

[edwvee]

@edwvee I think the error you are getting is because you are using older version of redis that does not support CLIENT SETINFO. The go-redis client will try to set its library information as part of the handshake for the connection. You can disable this by using https://github.com/redis/go-redis?tab=readme-ov-file#disabling-identity-verification I would advice you to update your redis to a newer version and update the client to the latest release (see the note about the typo in the option).

Let me know if this helps. If your problem is resolved, please close this issue.

Thank you. I'll try without updating redis. I have updated the library and added DisableIdentity. But in general I can't say is problem solved or not. It's a rare error that occurs ones a week or so.

[ndyakov]

@edwvee sounds good, I will close this issue, feel free to reopen if the error reoccurs.