feat: Add stopping to federate (WPB-203)

[thisisamir98]

WPB-203 [Web] System message when stopping to federate

This pull request implements a set of client-side actions to handle events related to federated communication termination. The specification outlines the steps for two types of events: federation.delete and federation.connectionRemoved. The main focus is on cleaning up local state after receiving these events and inserting a system message to explain what happened to the user.

For the federation.delete event: (Backend A has stopped federating with us)

• receive the event from backend
• leave the conversations locally that are owned by the backend A which was deleted.
• remove the deleted backend A users locally from our own conversations.
• insert system message to the affected conversations about federation termination.

For the federation.connectionRemoved event: (Backend A & B stopped federating, user is on C)

• receive the event from backend
• Identify all conversations that are not owned from A or B domain and that contain users from A and B
  • remove users from A and B from those conversations
  • insert system message in those conversations about backend A and B stopping to federate
• identify all conversations owned by domain A that contains users from B
  • remove users from B from those conversations
  • insert system message in those conversations about backend A and B stopping to federate
• Identify all conversations owned by domain B that contains users from A
  • remove users from A from those conversations
  • insert system message in those conversations about backend A and B stopping to federate

[codecov]

Codecov Report

Merging #15583 (1be8626) into dev (72d4f4b) will decrease coverage by 0.15%.
The diff coverage is 8.00%.

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  Lines       22189    22280      +91     
  Branches     5080     5096      +16     
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+ Hits         9656     9664       +8     
- Misses      11294    11377      +83     
  Partials     1239     1239              

[atomrc]

let's convert that into a switch in case we will need to handle more events of this type in the future.
Also we could early return in case the type has been matched

[thisisamir98]

done in 76d1df0

[atomrc]

don't we need to handle the connectionRemove event (and display it) as well?

[thisisamir98]

this is the event that we are creating on the client side for the system message, connection removed is handled here:
https://github.com/wireapp/wire-webapp/pull/15583/files#diff-8424911ba55dc95ddd7ee35e77e651a8894faa0c33cd485cbbf62f6537fe3d24R327-R329

[atomrc]

but there is no system message for connectionRemoved event?

[atomrc]

note for the future, I'd like the EventRepo to not really filter the type of events.
It should just send all the events in a single event and all the repos subscribing to it will make the work of filtering depending on the event type. :)

[arjita-mitra]

these two blocks are almost identical except domain type. We can create a function and call it twice with each domain.

const handleFederationUsers = async (domainToFilter: string, userDomainToDelete: string) => {
  allConversations
    .filter(conversation => conversation.domain === domainToFilter)
    .forEach(async conversation => {
      const usersToDelete = conversation.allUserEntities().filter(user => user.domain === userDomainToDelete);
      if (usersToDelete.length > 0) {
        await this.removeDeletedFederationUsers(conversation, usersToDelete);
        await this.insertFederationStopSystemMessage(conversation, [domainOne, domainTwo]);
      }
    });
};

await handleFederationUsers(domainOne, domainTwo);
await handleFederationUsers(domainTwo, domainOne);

[atomrc]

that's is a good suggestion, indeed. But without unit tests to back it, it's also risky.
I'd recommend writing tests first (I can help with that), make sure that we are compliant with the specs and then refactoring to a cleaner/more performant code.

will do it in separate PR