:claude: ## Summary Roll out the search relevancy join key currently behind the `search_relevancy_join_key` feature flag. - DRI: @johnmason - Team Slack channel: `#g_global_search` Introduced by gitlab-org/gitlab!253076. The flag gates a single per-request UUID (`search_request_id`) that is attached to the `perform_search` internal event (as the built-in `property` additional property), to `click_search_result` (via a `data-event-property` attribute on each result link), and to the structured request log as `meta.search.request_id`. With the flag off, both event payloads and the log line are byte-identical to today's. > [!note] > Process and guidance live in the docs — this issue is just the commands and a place to track the rollout. > "Rolling out" means incrementally enabling the flag on GitLab.com to validate stability — it is not the same as releasing the feature, which happens when the flag is removed. > [Feature flag controls](https://docs.gitlab.com/development/feature_flags/controls/) · [Feature flag lifecycle](https://handbook.gitlab.com/handbook/product-development/how-we-work/product-development-flow/feature-flag-lifecycle/#feature-flag-lifecycle) ## What could go wrong? Blast radius is the global search results page and the `perform_search` / `click_search_result` Snowplow events. - **Payload shape change.** `perform_search` gains a populated `property` field and `click_search_result`'s previously-declared-but-never-populated `property` field starts carrying values. Nothing reads `property` today — the only two metrics on `click_search_result` (`count_distinct_user_id_from_click_search_result_weekly` and its `counts_28d` twin) are `unique: user.id` with no filter — so no metric should move. Watch for a step change in either metric anyway. - **Render cost.** The join key is a memoized `SecureRandom.uuid` per request and the flag predicate is memoized per request, so the added per-result work is a hash key. Watch search page render duration. - **Volume.** The UUID adds ~36 bytes per result link to the HTML and one field to the request log. - Dashboards: search service dashboards on https://dashboards.gitlab.net, plus the Snowplow event volume for `perform_search` and `click_search_result`. Rollback is a single chatops command and is fully safe: the flag only adds fields, it changes no query, no ranking, and no permission check. ## Rollout Run all production `/chatops` in [`#production`](https://gitlab.slack.com/archives/C101F3796) and cross-post the results to `#g_global_search`. Background: [incremental rollout process](https://docs.gitlab.com/development/feature_flags/controls/#process), [feature actors](https://docs.gitlab.com/development/feature_flags/#feature-actors). The flag actor is `Feature.current_request`, so a percentage rollout is a percentage of search requests (including anonymous search, which a `current_user` actor would have excluded entirely). **Non-production** ``` /chatops gitlab run feature set search_relevancy_join_key 50 --actors --dev --pre --staging --staging-ref /chatops gitlab run feature set search_relevancy_join_key true --dev --pre --staging --staging-ref ``` **Production** — percentage rollout (wait ≥15 min between steps, watch dashboards): ``` /chatops gitlab run feature set search_relevancy_join_key 1 --actors /chatops gitlab run feature set search_relevancy_join_key 10 --actors /chatops gitlab run feature set search_relevancy_join_key 25 --actors /chatops gitlab run feature set search_relevancy_join_key 50 --actors /chatops gitlab run feature set search_relevancy_join_key 100 --actors ``` Or target specific actors instead: ``` /chatops gitlab run feature set --project=gitlab-org/gitlab,gitlab-org/gitlab-foss search_relevancy_join_key true /chatops gitlab run feature set --group=gitlab-org,gitlab-com search_relevancy_join_key true /chatops gitlab run feature set --user=johnmason search_relevancy_join_key true ``` ## Before global rollout Confirm the relevant gotchas before going to 100% — see [enabling a feature for GitLab.com](https://docs.gitlab.com/development/feature_flags/controls/#enabling-a-feature-for-gitlabcom): - [ ] [Docs + version history](https://docs.gitlab.com/development/documentation/feature_flags/) updated — no user-facing docs change; this is instrumentation only. - [ ] [Breaking changes](https://docs.gitlab.com/development/documentation/release_notes/#deprecations-removals-and-breaking-changes) announced — none. `click_search_result`'s `property` field was declared as "search term" and never populated by any producer, so no historical values change meaning. - [ ] [Change management issue](https://handbook.gitlab.com/handbook/engineering/infrastructure-platforms/change-management/#feature-flags-and-the-change-management-process) opened, if required — not expected; additive instrumentation only. - [ ] [External API consumers](https://docs.gitlab.com/development/feature_flags/#do-not-use-feature-flags-in-external-api-consumers) — none. The flag is read only in `SearchController` and `SearchHelper`. - [ ] Analytics Instrumentation review confirms the Snowflake column semantics for the redefined `property` field. ## Cleanup Remove the flag once [deemed stable](https://handbook.gitlab.com/handbook/product-development/how-we-work/product-development-flow/feature-flag-lifecycle/#feature-flag-lifecycle) — see [cleaning up](https://docs.gitlab.com/development/feature_flags/controls/#cleaning-up). Track it here, or open a follow-up [Feature Flag Cleanup issue](https://gitlab.com/gitlab-org/gitlab/-/work_items/new?description_template=Feature%20Flag%20Cleanup). Remove the flag and its YAML definition from the codebase, then: ``` /chatops gitlab run release check <cleanup-merge-request-url> <milestone> /chatops gitlab run feature delete search_relevancy_join_key --dev --pre --staging --staging-ref --production ``` Cleanup removes: the `search_relevancy_join_key_enabled?` predicate in `app/helpers/search_helper.rb`, the branch in `SearchController#increment_search_counters`, the guard in `search_result_tracking_attrs`, and the flag-off spec contexts. ## Rollback ``` /chatops gitlab run feature set search_relevancy_join_key false # production /chatops gitlab run feature set search_relevancy_join_key false --dev --pre --staging --staging-ref # non-production /chatops gitlab run feature delete search_relevancy_join_key --dev --pre --staging --staging-ref --production # remove entirely ```