How to Contribute
When submitting a pull request (PR), please use the following guidelines:
- Make sure your code respects existing formatting conventions. In general, follow the same coding style as the code that you are modifying.
- For Intellij you can import our code style settings xml: druid_intellij_formatting.xml.
- For Eclipse you can import our code style settings xml: eclipse_formatting.xml.
- Do add/update documentation appropriately for the change you are making.
- If you are introducing a new feature you may want to first submit your idea for feedback to the mailing list. Non-trivial features should include unit tests covering the new functionality.
- Bugfixes should include a unit test or integration test reproducing the issue.
- Do not use author tags/information in the code.
- Always include license header on each java file your create. See this example
- Try to keep pull requests short and submit separate ones for unrelated features, but feel free to combine simple bugfixes/tests into one pull request.
- Keep the number of commits small and combine commits for related changes. Each commit should compile on its own and ideally pass tests.
- Keep formatting changes in separate commits to make code reviews easier and distinguish them from actual code changes.
Fork the druid-io/druid repository into your GitHub account
Clone your fork of the GitHub repository
git clone email@example.com:<username>/druid.git
<username>with your GitHub username.
Add a remote to keep up with upstream changes
git remote add upstream https://github.com/druid-io/druid.git
If you already have a copy, fetch upstream changes
git fetch upstream
Create a feature branch to work in
git checkout -b feature-xxx remotes/upstream/master
Work in your feature branch
git commit -a
Periodically rebase your changes
git pull --rebase
When done, combine ("squash") related commits into a single one
git rebase -i upstream/master
This will open your editor and allow you to re-order commits and merge them:
- Re-order the lines to change commit order (to the extent possible without creating conflicts)
- Prefix commits using
f(fixup) to merge extraneous commits.
Submit a pull-request
git push origin feature-xxx
Go to your Druid fork main page
If you recently pushed your changes GitHub will automatically pop up a
Compare & pull requestbutton for any branches you recently pushed to. If you click that button it will automatically offer you to submit your pull-request to the druid-io/druid repository.
- Give your pull-request a meaningful title.
- In the description, explain your changes and the problem they are solving.
Addressing code review comments
Repeat steps 5. through 7. to address any code review comments and rebase your changes if necessary.
Push your updated changes to update the pull request
git push origin [--force] feature-xxx
--forcemay be necessary to overwrite your existing pull request in case your commit history was changed when performing the rebase.
Note: Be careful when using
--forcesince you may lose data if you are not careful.
git push origin --force feature-xxx
Help! I merged changes from upstream and cannot figure out how to resolve conflicts when rebasing!
Never fear! If you occasionally merged upstream/master, here is another way to squash your changes into a single commit:
First, rename your existing branch to something else, e.g.
git branch -m feature-xxx-unclean
Checkout a new branch with the original name
feature-xxxfrom upstream. This branch will supercede our old one.
git checkout -b feature-xxx upstream/master
Then merge your changes in your original feature branch
feature-xxx-uncleanand create a single commit.
git merge --squash feature-xxx-unclean git commit
You can now submit this new branch and create or replace your existing pull request.
git push origin [--force] feature-xxx:feature-xxx