Add MKSTREAM support [DATAREDIS-1042]

[spring-projects-issues]

Kevin McLaughlin opened DATAREDIS-1042 and commented

 

Add support for MKSTREAM option to createGroup operations (XGROUP) in ReactiveStreamOperations.

Right now you can't create a consumer group unless the stream already exists.  You get:

 

ERR The XGROUP subcommand requires the key to exist. Note that for CREATE you may want to use the MKSTREAM option to create an empty stream automatically

 

Use case:  Subscribe to a stream before it actually exists (but, most likely will be created very shortly by the 'publishing' service).

 

References:

redis/lettuce#898

https://github.com/antirez/redis/issues/4824

 

 

 

---

Referenced from: pull request #527

[spring-projects-issues]

Kevin McLaughlin commented

Workaround:

 

RedisScript<Void> script = RedisScript.of("redis.call(\"XGROUP\", \"CREATE\", KEYS[1], ARGV[1], \"$\", \"MKSTREAM\")");
redis.execute(script, singletonList(stream), singletonList(consumer.getGroup())).blockFirst();