guybe7 3d0b427c30
Fix some issues with modules and MULTI/EXEC (#8617)
Bug 1:
When a module ctx is freed moduleHandlePropagationAfterCommandCallback
is called and handles propagation. We want to prevent it from propagating
commands that were not replicated by the same context. Example:
1. module1.foo does: RM_Replicate(cmd1); RM_Call(cmd2); RM_Replicate(cmd3)
2. RM_Replicate(cmd1) propagates MULTI and adds cmd1 to also_propagagte
3. RM_Call(cmd2) create a new ctx, calls call() and destroys the ctx.
4. moduleHandlePropagationAfterCommandCallback is called, calling
   alsoPropagates EXEC (Note: EXEC is still not written to socket),
   setting server.in_trnsaction = 0
5. RM_Replicate(cmd3) is called, propagagting yet another MULTI (now
   we have nested MULTI calls, which is no good) and then cmd3

We must prevent RM_Call(cmd2) from resetting server.in_transaction.
REDISMODULE_CTX_MULTI_EMITTED was revived for that purpose.

Bug 2:
Fix issues with nested RM_Call where some have '!' and some don't.
Example:
1. module1.foo does RM_Call of module2.bar without replication (i.e. no '!')
2. module2.bar internally calls RM_Call of INCR with '!'
3. at the end of module1.foo we call RM_ReplicateVerbatim

We want the replica/AOF to see only module1.foo and not the INCR from module2.bar

Introduced a global replication_allowed flag inside RM_Call to determine
whether we need to replicate or not (even if '!' was specified)

Other changes:
Split beforePropagateMultiOrExec to beforePropagateMulti afterPropagateExec
just for better readability
2021-03-10 18:02:17 +02:00
..
2019-12-17 07:49:21 +00:00
2021-01-23 21:53:58 +02:00
2021-01-28 16:19:43 +02:00
2020-11-11 22:57:33 +02:00
2021-02-05 19:54:01 +02:00