Code Reviews

Code Reviews

Cinder follows the same Review guidelines outlined by the OpenStack community. This page provides additional information that is helpful for reviewers of patches to Cinder.


Cinder uses the Gerrit tool to review proposed code changes. The review site is

Gerrit is a complete replacement for Github pull requests. All Github pull requests to the Cinder repository will be ignored.

See Gerrit Workflow Quick Reference for information about how to get started using Gerrit. See Development Workflow for more detailed documentation on how to work with Gerrit.

Targeting Milestones

In an effort to guide team review priorities the Cinder team has adopted the process of adding comments to reviews to target a milestone for a particular patch. This process is not required for all patches but is beneficial for patches that may be time sensitive. For example patches that need to land earlier in the release cycle so as to get additional test time or because later development activities are dependent upon that functionality merging.

To target a patch to a milestone a reviewer should add a comment using the following format:


Release should be used to indicate the release to which the patch should be targeted, all lower case. The milestone is a single number, 1 to 3, indicating the milestone number. So, to target a patch to land in Milestone 2 of the Rocky release a comment like the following would be added:


Adding this tag allows reviewers to search for these tags and use them as a guide in review priorities.

Targeting patches should be done by Cinder Core Review Team members. If a patch developer feels that a patch should be targeted to a milestone the developer should bring the request up to the Cinder team in a weekly meeting or on the #openstack-cinder Freenode IRC channel.

Reviewing Vendor Patches

It is important to consider, when reviewing patches to a vendor’s Cinder driver, whether the patch passes the vendor’s CI process. CI reports are the only tool we have to ensure that a patch works with the Vendor’s driver. A patch to a vendor’s driver that does not pass that vendor’s CI should not be merged. If a patch is submitted by a person that does not work with the vendor that owns the driver, a +1 review from someone at that vendor is also required. Finally, a patch should not be merged before the Vendor’s CI has run against the patch.


Patches which have passed vendor CI and have merged in master are exempt from this requirement upon backport to stable and/or driverfixes branches as vendors are not required to run CI on those branches. If the vendor, however, is running CI on stable and/or driverfix branches failures should not be ignored unless otherwise verified by a developer from the vendor.

Unit Tests

Cinder requires unit tests with all patches that introduce a new branch or function in the code. Changes that do not come with a unit test change should be considered closely and usually returned to the submitter with a request for the addition of unit test.


Unit test changes are not validated in any way by vendor’s CI. Vendor CI’s run the tempest volume tests against a change which does not include a unit test execution.

Creative Commons Attribution 3.0 License

Except where otherwise noted, this document is licensed under Creative Commons Attribution 3.0 License. See all OpenStack Legal Documents.