db_redis: add support for native redis cluster

[gedia]

The db_redis module seems to only support connecting with a single redis instance. It is not evident from the documentation if it implements support for native redis cluster by honouring 'MOVED' replies.

ndb_redis seems to have support for native redis clusters, and supports both automatic (see allow_dynamic_nodes parameter of ndb_redis) and manual configuration of redis nodes.

Since both modules are based on the hiredis library, is it safe to assume this support could be easily implemented, with some code sharing between the two modules perhaps?

If db_redis supports clusters with automatic configuration only (by processing MOVED replies), perhaps the module's documentation should be updated to reflect that.

[miconda]

The two modules were developed independently. Maybe @agranig can comment if db_redis already supports or not processing MOVED replies.

[agranig]

Hey, unfortunately it doesn’t support it yet, and it’s not clear yet when I can address this, as I don’t have immediate needs for it.

[henningw]

@gedia as there seems no interest from in implementing this feature right now, this issue will be closed. If somebody wants to work on this, please re-open.