This section documents the process for reviewing and merging code changes contributed via Github Pull Requests. It assumes you have a clone of Kafka's Git repository.There are 2 approaches for merging:
- Via the GitHub merge button. This is simplest and GitHub will recognise the pull request as merge. However, it is up to the committer to format the commit message appropriately, close the relevant JIRA and cherry-pick the squashed commit to the relevant release branches (if necessary).
- Via the kafka-merge-pr.py script. The script automates a number of steps as described in the Merge Script section. The main downside is that GitHub will not recognise the pull request as merged (it will simply be closed).
A pull request is ready to be merged once:
- It has been reviewed and feedback has been addressed.
- The branch merges cleanly to trunk. If the branch merges cleanly to a stable branch, the code hasn't diverged and the committer deems it safe, it's OK to cherry-pick to a stable branch (manually with git or via the merge script). Otherwise, a separate PR should be submitted for the backport so that it can be reviewed and tested.
- Unit and integration tests have passed via the automated PR builds.
- System tests have passed, if applicable. For non trivial changes, we recommend running the system tests via https://jenkins.confluent.io/job/system-test-kafka-branch-builder/ before merging the PR. This is a manual process at the moment and it would be good to automate it in the future.
Merging via the GitHub Merge Button
Once the pull request is ready to be merged (as per the description above):
- Click on the "Squash and merge" button.
- Edit the commit title and description so that it follows the convention described in Contributing Code Changes. It should be a matter of copying and pasting from the pull request title and description, but they can often be improved. Unfortunately, GitHub's default strategy for the commit message is not great (it copies the message from each commit in the pull request).
- Mention the reviewers in a separate line. For example: "Reviewers: Joe Smith <firstname.lastname@example.org>, Mary Jane <email@example.com>".
- Click on the confirm button.
Merging via the Merge Script
kafka-merge-pr.py is a script that automates the process of accepting a code change into the project. It creates a temporary branch from
apache/trunk, squashes the commits in the pull request, rewrites the commit message in the squashed commit to follow a standard format including information about each original commit, merges the squashed commit into the temporary branch, pushes the code to
apache/trunk and closes the JIRA ticket. The push will then be mirrored to
apache-github/trunk, which will cause the PR to be closed due to the pattern in the commit message. Note that the script will ask the user before executing remote updates (ie git push and closing JIRA ticket), so it can still be used even if the user wants to skip those steps.
1. Clone Kafka's Git repository (if you haven't already).
2. Add aliases for the remotes expected by the merge script (if you haven't already):
git remote add apache https://git-wip-us.apache.org/repos/asf/kafka.git git remote add apache-github https://github.com/apache/kafka.git
23. Install jira-python:
sudo easy_install jira
Once the pull request is ready to be merged :
(as per the description above):
1. Set the
JIRA_PASSWORD environment variables with the appropriate credentials if you intend to ask the script to close the issue associated with the pull request.
2. Run the merge script:
3. Answer the questions prompted by the script.