WPB-21964: Add Wire Meetings delete

[blackheaven]

https://wearezeta.atlassian.net/browse/WPB-21964

Checklist

• Add a new entry in an appropriate subdirectory of changelog.d
• Read and follow the PR guidelines

[battermann]

Other than the 2 comments, it looks good!

[battermann]

This is a bit strange, I would assume the ConversationSubsystem to also handle authorization/team membership checks.

[blackheaven]

I would agree, except that:

• Other operations don't (I agree that it could be a defect)
• As far as I can see, only getLocalConvForUser, in galley do directly check permissions.

[battermann]

It is only delegating to ConversationStore, can't you use ConverstationStore directly where you need this? Otherwise it's the wrong abstraction, IMO.

[blackheaven]

@akshaymankar reminded me that we should not use other's subsystems store in #4918 (comment)

[battermann]

IDK, why shouldn't the meeting subsystem use the conversation store? Because a meeting is a conversation, right? (we should not be more catholic than the pope ;-))

[battermann]

If you ask me, the right solution would be to move all the code related to conversation deletion from galley to the conversation subsystem, including all the permission checks and what not. Then call this from here and also from galley. This would also solve the other comment about the team to conversation index and other clean up operations that are still missing here. But this would take some more effort as there are a lot of dependencies.

[battermann]

We should make sure that the team -> conversation index also gets removed (I think only relevant for cassandra)

[blackheaven]

Should it be part of ConversationSubsystem?

[battermann]

I am not sure. It would be best if it would use the same code as normal conversation deletion through the conversation action. There is even much more to consider than just the team to conversation index. See:

    SConversationDeleteTag -> do
      let deleteGroup groupId = do
            E.removeAllMLSClients groupId
            E.deleteAllProposals groupId

      let cid = storedConv.id_
      for_ (storedConv & mlsMetadata <&> cnvmlsGroupId . fst) $ \gidParent -> do
        sconvs <- E.listSubConversations cid
        for_ (Map.assocs sconvs) $ \(subid, mlsData) -> do
          let gidSub = cnvmlsGroupId mlsData
          E.deleteSubConversation cid subid
          deleteGroup gidSub
        deleteGroup gidParent

      key <- E.makeKey (tUnqualified lcnv)
      E.deleteCode key
      case convTeam storedConv of
        Nothing -> E.deleteConversation (tUnqualified lcnv)
        Just tid -> E.deleteTeamConversation tid (tUnqualified lcnv)

      pure $ mkPerformActionResult action

I don't know how to best achieve this, either.

[blackheaven]

added

[blackheaven]

See #5068

[battermann]

Now we have duplicated the conversation deletion logic. And compared to the galley implementation there are some other clean ups still missing. Also no permission check here.