v1.6.0 no longer works with Redis cluster

[pbstriker38]

Attempting to use defaults raises an error because the unwatch command is not supported on Redis clusters.

Loading development environment (Rails 7.0.8)
irb(main):001> last_seen_at = Kredis.datetime('last_seen_at', default: 20.minutes.ago, expires_in: 1.week)
[2023-10-31T16:28:21.283-07:00] INFO:   Kredis  (43.7ms)  Connected to shared
[2023-10-31T16:28:21.289-07:00] DEBUG:   Kredis Proxy (1.6ms)  EXISTS? last_seen_at  
[2023-10-31T16:28:21.291-07:00] DEBUG:   Kredis Proxy (1.6ms)  SET last_seen_at ["2023-10-31T23:08:21.239912000Z"] {:ex=>1 week}
/.rbenv/versions/3.2.2/lib/ruby/gems/3.2.0/gems/redis-4.8.1/lib/redis/cluster.rb:152:in `send_command': Cluster client doesn't know which node the unwatch command should be sent to. (Redis::Cluster::AmbiguousNodeError)
/.rbenv/versions/3.2.2/lib/ruby/gems/3.2.0/gems/redis-4.8.1/lib/redis/cluster.rb:152:in `send_command': Cluster client doesn't know which node the unwatch command should be sent to. (Redis::Cluster::AmbiguousNodeError)

https://github.com/redis/redis-rb/blob/v4.8.1/lib/redis/cluster.rb#L151

[dhh]

cc @lewispb

[lewispb]

I just ran the test suite against Redis Cluster locally and most of it failed. Looks like we don't support Redis Cluster.

It's not just unwatch that's unsupported, multi and mget are too, both of which are used by Kredis.

We could add a note to the Readme perhaps? #137

[KJTsanaktsidis]

It's not just unwatch that's unsupported, multi and mget are too, both of which are used by Kredis.

FWIW I'm in the process of trying to get as much of watch/multi as makes sense working with the Ruby redis cluster driver: redis-rb/redis-cluster-client#299

Once we get that support landed, making kredis work with redis-cluster should be a case of figuring out which keys need to be accessed transactionally together, and adding {hashtags} to them so that they hash to the same slot