Why this change?
On CI, we have been seeing the "handles job concurrency" job timing out
on CI after 45 seconds. Upon closer inspection of `Jobs::Base#perform`
when cluster concurrency has been set, we see that a thread is spun up
to extend the expiring of a redis key by 120 seconds every 60 seconds
while the job is still being executed. The thread looks like this before
the fix:
```
keepalive_thread =
Thread.new do
while parent_thread.alive? && !finished
Discourse.redis.without_namespace.expire(cluster_concurrency_redis_key, 120)
sleep 60
end
end
```
In an ensure block of `Jobs::Base#perform`, the thread is stop by doing
something like this:
```
finished = true
keepalive_thread.wakeup
keepalive_thread.join
```
If the thread is sleeping, `keepalive_thread.wakeup` will stop the
`sleep` method and run the next iteration causing the thread to
complete. However, there is a timing issue at play here. If
`keepalive_thread.wakeup` is called at a time when the thread is not
sleeping, it will have no effect and the thread may end up sleeping for
60 seconds which is longer than our timeout on CI of 45 seconds.
What does this change do?
1. Change `sleep 60` to sleep in intervals of 1 second checking if the
job has been finished each time.
2. Add `use_redis_snapshotting` to `Jobs::Base` spec since Redis is
involved in scheduling and we want to ensure we don't leak Redis
keys.
3. Add `ConcurrentJob.stop!` and `thread.join` to `ensure` block in "handles job concurrency"
test since a failing expectation will cause us to not clean up the
thread we created in the test.
Anonymization is among the most expensive operations we can perform with
extreme potential to impact the database. To mitigate risk we only allow a
single anonymization across the entire cluster concurrently.
This commit introduces support for `cluster_concurrency 1`. When you set that on a Job it will only allow 1 concurrent execution per cluster.
```
class Jobs::DummyDelayedJob < Jobs::Base
def execute(args = {})
end
end
RSpec.describe "Jobs.run_immediately!" do
before { Jobs.run_immediately! }
it "explodes" do
current_user = Fabricate(:user)
Jobs.enqueue_in(1.seconds, :dummy_delayed_job)
sign_in(current_user)
end
end
```
The test above will fail with the following error if `ActiveRecord::Base.connection_handler.clear_active_connections!` is called before the configured Capybara server checks out a connection from the connection pool.
```
ActiveRecord::ActiveRecordError:
Cannot expire connection, it is owned by a different thread: #<Thread:0x00007f437391df58@puma srv tp 001 /home/tgxworld/.asdf/installs/ruby/3.1.3/lib/ruby/gems/3.1.0/gems/puma-6.0.2/lib/puma/thread_pool.rb:106 sleep_forever>. Current thread: #<Thread:0x00007f437d6cfc60 run>.
```
We're not exactly sure if this is an ActiveRecord bug or not but we've
invested too much time into investigating this problem. Fundamentally,
we also no longer understand why `ActiveRecord::Base.connection_handler.clear_active_connections!` is being called in an ensure block
within `Jobs::Base#perform` which was added in
ceddb6e0da 10 years ago. This
commit moves the logic for running jobs immediately out of the
`Jobs::Base#perform` method into another `Jobs::Base#perform_immediately` method such that
`ActiveRecord::Base.connection_handler.clear_active_connections!` is not
called. This change will only impact the test environment.
Our internal implementation of #perform on jobs performs remapping.
This happens cause we do "exception aggregation".
Scheduled jobs run on every site in the multisite cluster, and we report
one error per site that failed. During this aggregation we reshape the
context from the original object shape returned by mini_scheduler
The new integration test ensures this interface will remain stable even if
decoupled parts of the code change shapes.
Co-authored-by: Alan Guo Xiang Tan <gxtan1990@gmail.com>
It's very easy to forget to add `require 'rails_helper'` at the top of every core/plugin spec file, and omissions can cause some very confusing/sporadic errors.
By setting this flag in `.rspec`, we can remove the need for `require 'rails_helper'` entirely.
When running jobs in tests, we use `Jobs.run_immediately!`. This means that jobs are run synchronously when they are enqueued. Jobs sometimes enqueue other jobs, which are also executed synchronously. This means that the outermost job will block until the inner jobs have finished executing. In some cases (e.g. process_post with hotlinked images) this can lead to a deadlock.
This commit changes the behavior slightly. Now we will never run jobs inside other jobs. Instead, we will queue them up and run them sequentially in the order they were enqueued. As a whole, they are still executed synchronously. Consider the example
```ruby
class Jobs::InnerJob < Jobs::Base
def execute(args)
puts "Running inner job"
end
end
class Jobs::OuterJob < Jobs::Base
def execute(args)
puts "Starting outer job"
Jobs.enqueue(:inner_job)
puts "Finished outer job"
end
end
Jobs.enqueue(:outer_job)
puts "All jobs complete"
```
The old behavior would result in:
```
Starting outer job
Running inner job
Finished outer job
All jobs complete
```
The new behavior will result in:
```
Starting outer job
Finished outer job
Running inner job
All jobs complete
```
Zeitwerk simplifies working with dependencies in dev and makes it easier reloading class chains.
We no longer need to use Rails "require_dependency" anywhere and instead can just use standard
Ruby patterns to require files.
This is a far reaching change and we expect some followups here.
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
Since rspec-rails 3, the default installation creates two helper files:
* `spec_helper.rb`
* `rails_helper.rb`
`spec_helper.rb` is intended as a way of running specs that do not
require Rails, whereas `rails_helper.rb` loads Rails (as Discourse's
current `spec_helper.rb` does).
For more information:
https://www.relishapp.com/rspec/rspec-rails/docs/upgrade#default-helper-files
In this commit, I've simply replaced all instances of `spec_helper` with
`rails_helper`, and renamed the original `spec_helper.rb`.
This brings the Discourse project closer to the standard usage of RSpec
in a Rails app.
At present, every spec relies on loading Rails, but there are likely
many that don't need to. In a future pull request, I hope to introduce a
separate, minimal `spec_helper.rb` which can be used in tests which
don't rely on Rails.
update rspec syntax to v3
change syntax to rspec v3
oops. fix typo
mailers classes with rspec3 syntax
helpers with rspec3 syntax
jobs with rspec3 syntax
serializers with rspec3 syntax
views with rspec3 syntax
support to rspec3 syntax
category spec with rspec3 syntax
