New modules APIs

[Salvatore Sanfilippo]

Hi all,

I just pushed a few changes to the Cluster and Timer API online:

0d6f11f4 Module cluster flags: use RM_SetClusterFlags() in the example.
3213e8de Module cluster flags: add RM_SetClusterFlags() API.
777cc5b9 Module cluster flags: add hooks for NO_FAILOVER flag.
c202ba2b Module cluster flags: add hooks for NO_REDIRECTION flag.
744fe7f3 Module cluster flags: initial vars / defines added.
7cdf272d Modules: rename the reused static client to something more general.
9df1f73e Modules: associate a fake client to timer context callback.
bf180440 Modules: associate a fake client to cluster message context callback.

Basically now a module is able to disable two major Redis Cluster
features, failover and keys redirection (partitioning), so that the
module is more free to do whatever it needed.
Moreover a bug was fixed preventing the handlers of cluster messages
and timers from using RedisModule_Call() and other APIs.

So now it looks like there are all the basics to create some more
serious cluster module. I plan to continue adding a few things, and
finally create an example module that implements a toy distributed
system on top of Redis.

Cheers,
Salvatore

--
Salvatore 'antirez' Sanfilippo
open source developer - Redis Labs https://redislabs.com

"If a system is to have conceptual integrity, someone must control the
concepts."
— Fred Brooks, "The Mythical Man-Month", 1975.