When a user archives a personal message, they are redirected back to the
inbox and will refresh the list of the topics for the given filter.
Publishing an event to the user results in an incorrect incoming message
because the list of topics has already been refreshed.
This does mean that if a user has two tabs opened, the non-active tab
will not receive the incoming message but at this point we do not think
the technical trade-offs are worth it to support this feature. We
basically have to somehow exclude a client from an incoming message
which is not easy to do.
Follow-up to fc1fd1b416
There are certain design decisions that were made in this commit.
Private messages implements its own version of topic tracking state because there are significant differences between regular and private_message topics. Regular topics have to track categories and tags while private messages do not. It is much easier to design the new topic tracking state if we maintain two different classes, instead of trying to mash this two worlds together.
One MessageBus channel per user and one MessageBus channel per group. This allows each user and each group to have their own channel backlog instead of having one global channel which requires the client to filter away unrelated messages.
This change both speeds up specs (less strings to allocate) and helps catch
cases where methods in Discourse are mutating inputs.
Overall we will be migrating everything to use #frozen_string_literal: true
it will take a while, but this is the first and safest move in this direction
