Why this change?
We have been debugging flaky system tests and noticed in https://github.com/discourse/discourse/actions/runs/7911902047/job/21596791343?pr=25690
that ActiveRecord connection checkout timeouts are encountered because
the Capybara server thread is processing requests even after
`Capybara.reset_session!` and ActiveRecord's `teardown_fixtures` have already been call.
The theory here is that an inflight request can still hit the Capybara
server even after `Capybara.reset_session!` has been called and end up
eating up an ActiveRecord connection for too long and also messing with
the database outside of a transaction.
What does this change do?
This change adds a `BlockRequestsMiddleware` middleware in the test
environment which is enabled to reject all incoming requests at the end
of each system test and before `Capybara.reset_session!` is called. At
the start of each RSpec test, the middleware is disabled again.
This commit adds the RailsMultisite middleware in test mode when Rails.configuration.multisite is true. This allows for much more realistic integration testing. The `multisite_spec.rb` file is rewritten to avoid needing to simulate a middleware stack.
Upgrades Rails to latest, this version has better compatibility
with Ruby 2.7
During the upgrade we needed a new cleaner mechanism for configuring
message bus.
All tests are green.
If anything weird pops up please revert.
Alan Guo Xiang Tan
David Taylor
Jarek Radosz
Josh Soref
Daniel Waterworth
Guo Xiang Tan
Sam Saffron