Previously, we called the `peek_enabled?` method like so:
prepend_before_action :set_peek_request_id, if: :peek_enabled?
Now we don't have a `set_peek_request_id` method, so we don't need that
line. However, the `peek_enabled?` part had a side-effect: it would also
populate the request store cache for whether the performance bar was
enabled for the current request or not.
This commit makes that side-effect explicit, and replaces all uses of
`peek_enabled?` with the more explicit
`Gitlab::PerformanceBar.enabled_for_request?`. There is one spec that
still sets `SafeRequestStore[:peek_enabled]` directly, because it is
contrasting behaviour with and without a request store enabled.
The upshot is:
1. We still set the value in one place. We make it more explicit that
that's what we're doing.
2. Reading that value uses a consistent method so it's easier to find in
future.
This will help diagnose the source of excessive I/O from Rugged
calls. To implement this, we need to obtain the full list of arguments
sent to each request method.
This adds `rugged_duration_ms` and `rugged_calls` fields to
`api_json.log` and `production_json.log`. This will make it easier to
identify performance issues caused by excessive I/O.
Closes https://gitlab.com/gitlab-org/gitlab-ce/issues/64676