_This ticket was created from_ [_INC-348_](https://app.incident.io/gitlab/incidents/348) _and was automatically exported by_ [_incident.io_](https://app.incident.io) 🔥 In this incident occured after we merged https://gitlab.com/gitlab-org/gitlab/-/merge_requests/184507, in which we made sure that SLIs were correctly initialized again. We did not notice that the metrics emitted used a slightly different labelset: the apdex-sli did not pass an `error_type=""` label which made the endpoint fail at runtime. We did not catch this in tests, even thought he SLIs are tested, because the initializers don't run in tests. The error that was raised was this one from `prometheus-client-mmap`: https://gitlab.com/gitlab-org/ruby/gems/prometheus-client-mmap/-/blob/7a2dff5bee7a98420a56c9cc320a88d68756e8c8/lib/prometheus/client/label_set_validator.rb#L38-40 In the fix MR, we added a spec that explicitly enables the SLIs that concern the particular endpoint we're talking about: https://gitlab.com/gitlab-org/gitlab/-/merge_requests/186061. We should make sure that this is the case for all controller and request specs, but only run the initialization once per suite. We should also make sure that this plays nicely with the [`:prometheus`](https://gitlab.com/gitlab-org/gitlab/-/blob/489436e067af593883afc6ee5208d8c2f126cd68/spec/spec_helper.rb#L484-489) spec helper that specs use to ensure they have predictable data inside prometheus for a spec.