Code Reviews

All Kolla code must be reviewed and approved before it can be merged. Anyone with a Gerrit account is able to provide a review. Two labels are available to everyone:

  • +1: Approve

  • -1: Changes requested

It is also possible to leave comments without a label. In general, a review with comments is more valuable. Comments are especially important for a negative review. Prefer quality of reviews over quantity.

You can watch specific patches in Gerrit via Settings -> Watched Projects. The volume of emails is not too large if you subscribe to New Changes only. If you do not have much time available for reviewing, consider reviewing patches in an area that is important to you or that you understand well.

Core reviewer groups

There are two core reviewer groups in the Kolla project, each with different levels of access.

kolla-core

Members of kolla-core have the following additional labels available:

  • +2: Approve

  • -2: Do not merge

  • Workflow +1: Approve and ready for merge

Zuul requires one +2 and one workflow +1, as well as a passing check, in order for a patch to proceed to the gate.

We also have some non-voting Zuul jobs which will not block a check, but should be investigated if they are failing.

The Kolla project generally requires two +2s before a workflow +1 may be added. Exceptions where a single +2 is sufficient before adding workflow +1 are:

  • CI-only patches

  • Documentation patches

  • Trivial patches

kolla-core members may still use +1 to indicate approval if they are not confident enough about a particular patch to use +2.

kolla-core members have the same rights of access to stable branches, so always check the branch for a review, and use extra care with stable branches.

kolla-reviewers

Members of kolla-reviewers have the following additional labels available:

  • +2: Approve

  • -2: Do not merge

kolla-reviewers members do not have workflow rights and cannot approve a patch for merging. Their +2 counts toward the two +2s required before a kolla-core member may add a workflow +1.

kolla-reviewers members may still use +1 to indicate approval if they are not confident enough about a particular patch to use +2.

Becoming a core reviewer

There are no strict rules for becoming a core reviewer. Join the community, review some patches, and demonstrate responsibility, understanding & care. If you are interested in joining the core team, ask the PTL or another core reviewer how to get there.

Stale patches

If a reviewed patch has received no response from its owner for two weeks, it is at the discretion and motivation of the core reviewers to update and carry that patch forward if they deem it valuable for the upcoming release. In that case, the core reviewer taking ownership of the patch should add their own DCO signoff (Signed-off-by:) to the commit message.