[Feature flag] Rollout of `use_repository_list_tags_on_graphql`
Summary
This issue is to rollout the feature, Use the list repository tags API and its pagina... (#411387 - closed), on production,
that is currently behind the use_repository_list_tags_on_graphql
feature flag.
This feature uses the list repository tags API endpoint of the Container Registry to fetch, filter, and paginate repository tags in the Gitlab UI via GraphQL.
This feature is available for migrated container repositories (i.e. those on Gitlab.com
).
Owners
- Team:
Container Registry | Package
- Most appropriate slack channel to reach out to:
#g_container_registry
- Best individual to reach out to:
@adie.po
- PM:
@trizzi
Expectations
-
With the feature flag being on, we will see more traffic to the list repository tags API endpoint. This can be monitored via the logs.
-
List Repository Tags Page will still behave as before, no change in the behaviour perceived by the user.
-
When we inspect the page, under Networks, we would see tag names as the cursors (as opposed to random strings generated by GraphQL). This is because we supply the cursors that the API returns as we use the externally paginated results.
- Before:
"pageInfo": { ... "startCursor": "MQ", "endCursor": "MTA", "__typename": "PageInfo" }
- After:
"pageInfo": { ... "startCursor": "tag6", "endCursor": "tag10", "__typename": "PageInfo" }
- Before:
When is the feature viable?
After enabling the feature flag use_repository_list_tags_on_graphql
for a project, the change can already be observed in production for that project given that it is on Gitlab.com.
Chatops command to enable for a specific project:
/chatops run feature set --project=<name of test project> use_repository_list_tags_on_graphql true
Chatops command to run for the test projects:
Staging:
/chatops run feature set --project=test-group-tags-api/test-project-tags-api use_repository_list_tags_on_graphql true
Production:
/chatops run feature set --project=test-group-for-tags-api/test-project-for-tags-api use_repository_list_tags_on_graphql true
What might happen if this goes wrong?
-
Feature flag can be turned off:
-
Feature.disable(:use_repository_list_tags_on_graphql)
-
/chatops run feature set use_repository_list_tags_on_graphql false
-
/chatops run feature set --project=<project-path> use_repository_list_tags_on_graphql false
-
-
Worst case, the MR can be rolled back: !132716 (merged)
What can we check for monitoring production after rollouts?
-
Logs where we can check the requests to the list repository tags endpoint. URL would be
gitlab/v1/<project path>/tags/list
. -
Container Repository tags page to see that pagination, filtering, and sorting still works as it did before.
Rollout Steps
Preparation
- Create a new group and a new project. Upload several (> 10) images to the container registry.
- Here are sample projects already created with multi-page images:
- Enable the feature flag for that specific project
/chatops run feature set --project=<name of test project> use_repository_list_tags_on_graphql true
- Head over to the container repository tags page.
- Gitlab Production: https://gitlab.com/test-group-for-tags-api/test-project-for-tags-api/container_registry/5678491
- Gitlab Staging: https://staging.gitlab.com/test-group-tags-api/test-project-tags-api/container_registry/1099768
- Test the sorting, filtering, and pagination.
- Expect the Network tab of the page and observe the cursors.
Note: Please make sure to run the chatops commands in the slack channel that gets impacted by the command.
Rollout on non-production environments
-
Verify the MR with the feature flag is merged to master. -
Verify that the feature MRs have been deployed to non-production environments with:
-
/chatops run auto_deploy status <merge-commit-of-your-feature>
-
-
Deploy the feature flag at a percentage (recommended percentage: 50%) - The feature flag has an actor, perform actor-based rollout.
-
/chatops run feature set <feature-flag-name> <rollout-percentage> --actors --dev --staging --staging-ref
-
-
Monitor that the error rates did not increase (repeat with a different percentage as necessary)
- The feature flag has an actor, perform actor-based rollout.
-
Enable the feature globally on non-production environments. -
/chatops run feature set <feature-flag-name> true --dev --staging --staging-ref
- If the feature flag causes QA end-to-end tests to fail:
-
Disable the feature flag on staging to avoid blocking deployments.
-
-
-
Verify that the feature works as expected. Posting the QA result in this issue is preferable. The best environment to validate the feature in is staging-canary as this is the first environment deployed to. Note you will need to make sure you are configured to use canary as outlined here when accessing the staging environment in order to make sure you are testing appropriately.
For assistance with QA end-to-end test failures, please reach out via the #quality
Slack channel. Note that QA test failures on staging-ref don't block deployments.
Specific rollout on production
For visibility, all /chatops
commands that target production should be executed in the #production
slack channel and cross-posted (with the command results) to the responsible team's slack channel (#g_container_registry
).
- Ensure that the feature MRs have been deployed to both production and canary.
-
/chatops run auto_deploy status <merge-commit-of-your-feature>
-
- You must enable the feature on these entries:
-
/chatops run feature set --project=gitlab-org/gitlab,gitlab-org/gitlab-foss,gitlab-com/www-gitlab-com use_repository_list_tags_on_graphql true
-
-
Verify that the feature works on the specific entries. Posting the QA result in this issue is preferable.
Preparation before global rollout
-
Set a milestone to the rollout issue to signal for enabling and removing the feature flag when it is stable. -
Check if the feature flag change needs to be accompanied with a change management issue. Cross link the issue here if it does. -
Ensure that you or a representative in development can be available for at least 2 hours after feature flag updates in production. If a different developer will be covering, or an exception is needed, please inform the oncall SRE by using the @sre-oncall
Slack alias. -
Ensure that documentation has been updated (More info). -
Leave a comment on the feature issue announcing estimated time when this feature flag will be enabled on GitLab.com. -
Ensure that any breaking changes have been announced following the release post process to ensure GitLab customers are aware. -
Notify #support_gitlab-com
and your team channel (more guidance when this is necessary in the dev docs). -
Ensure that the feature flag rollout plan is reviewed by another developer familiar with the domain.
Global rollout on production
For visibility, all /chatops
commands that target production should be executed in the #production
slack channel and cross-posted (with the command results) to the responsible team's slack channel (#g_TEAM_NAME
).
-
Incrementally roll out the feature. -
Between every step wait for at least 15 minutes and monitor the appropriate graphs on https://dashboards.gitlab.net. - If the feature flag in code has an actor, perform actor-based rollout. For a reference on how to choose the percentages, see here
-
/chatops run feature set <feature-flag-name> <rollout-percentage> --actors
-
- Enable the feature globally on production environment.
-
/chatops run feature set <feature-flag-name> true
-
-
-
Observe appropriate graphs on https://dashboards.gitlab.net and verify that services are not affected. -
Leave a comment on the feature issue announcing that the feature has been globally enabled. -
Wait for at least one day for the verification term.
(Optional) Release the feature with the feature flag
If you're still unsure whether the feature is deemed stable but want to release it in the current milestone, you can change the default state of the feature flag to be enabled. To do so, follow these steps:
-
Create a merge request with the following changes. Ask for review and merge it. -
Set the default_enabled
attribute in the feature flag definition totrue
. -
Review what warrants a changelog entry and decide if a changelog entry is needed.
-
-
Ensure that the default-enabling MR has been included in the release package. If the merge request was deployed before the monthly release was tagged, the feature can be officially announced in a release blog post. -
/chatops run release check <merge-request-url> <milestone>
-
-
Consider cleaning up the feature flag from all environments by running these chatops command in #production
channel. Otherwise these settings may override the default enabled.-
/chatops run feature delete <feature-flag-name> --dev --staging --staging-ref --production
-
-
Close the feature issue to indicate the feature will be released in the current milestone. -
Set the next milestone to this rollout issue for scheduling the flag removal. -
(Optional) You can create a separate issue for scheduling the steps below to Release the feature. -
Set the title to "[Feature flag] Cleanup <feature-flag-name>
". -
Execute the /copy_metadata <this-rollout-issue-link>
quick action to copy the labels from this rollout issue. -
Link this rollout issue as a related issue. -
Close this rollout issue.
-
WARNING: This approach has the downside that it makes it difficult for us to clean up the flag. For example, on-premise users could disable the feature on their GitLab instance. But when you remove the flag at some point, they suddenly see the feature as enabled and they can't roll it back to the previous behavior. To avoid this potential breaking change, use this approach only for urgent matters.
Release the feature
After the feature has been deemed stable, the clean up should be done as soon as possible to permanently enable the feature and reduce complexity in the codebase.
You can either create a follow-up issue for Feature Flag Cleanup or use the checklist below in this same issue.
-
Create a merge request to remove <feature-flag-name>
feature flag. Ask for review and merge it.-
Remove all references to the feature flag from the codebase. -
Remove the YAML definitions for the feature from the repository. -
Create a changelog entry.
-
-
Ensure that the cleanup MR has been included in the release package. If the merge request was deployed before the monthly release was tagged, the feature can be officially announced in a release blog post. -
/chatops run release check <merge-request-url> <milestone>
-
-
Close the feature issue to indicate the feature will be released in the current milestone. -
Clean up the feature flag from all environments by running these chatops command in #production
channel:-
/chatops run feature delete <feature-flag-name> --dev --staging --staging-ref --production
-
-
Close this rollout issue.
Rollback Steps
-
This feature can be disabled by running the following Chatops command:
/chatops run feature set <feature-flag-name> false