# Contributing code to matrix-python-common Everyone is welcome to contribute code to matrix-python-common, provided you are willing to license your contributions under the same license as the project itself. In this case, the [Apache Software License v2](LICENSE). ## Set up your development environment To contribute to matrix-python-common, ensure you have Python 3.7 and `git` available on your system. You'll need to clone the source code first: ```shell git clone https://github.com/matrix-org/matrix-python-common.git ``` ## Create a virtualenv To contribute to matrix-python-common, ensure you have Python 3.7 or newer and then run: ```bash python3 -m venv .venv .venv/bin/pip install -e .[dev] ``` This creates an isolated virtual Python environment ("virtualenv") just for use with matrix-python-common, then installs matrix-python-common along with its dependencies, and lastly installs a handful of useful tools Finally, activate the virtualenv by running: ```bash source .venv/bin/activate ``` Be sure to do this _every time_ you open a new terminal window for working on matrix-python-common. Activating the venv ensures that any Python commands you run (`pip`, `python`, etc.) use the versions inside your venv, and not your system Python. When you're done, you can close your terminal or run `deactivate` to disable the virtualenv. ## Run the unit tests To make sure everything is working as expected, run the unit tests: ```bash tox -e py ``` If you see a message like: ``` ------------------------------------------------------------------------------- Ran 25 tests in 0.324s PASSED (successes=25) ``` Then all is well and you're ready to work! ## How to contribute The preferred and easiest way to contribute changes is to fork the relevant project on github, and then [create a pull request]( https://help.github.com/articles/using-pull-requests/) to ask us to pull your changes into our repo. Some other points to follow: * Please base your changes on the `main` branch. * Please follow the [code style requirements]( #code-style-and-continuous-integration). * Please [sign off](#sign-off) your contribution. * Please keep an eye on the pull request for feedback from the [continuous integration system](#code-style-and-continuous-integration) and try to fix any errors that come up. * If you need to [update your PR](#updating-your-pull-request), just add new commits to your branch rather than rebasing. ## Code style and continuous integration matrix-python-common uses `black`, `isort` and `flake8` to enforce code style. Use the following script to enforce these style guides: ```shell scripts-dev/lint.sh ``` (This also runs `mypy`, our preferred typechecker.) All of these checks are automatically run against any pull request via GitHub Actions. If your change breaks the build, this will be shown in GitHub, with links to the build results. If your build fails, please try to fix the errors and update your branch. ## Sign off In order to have a concrete record that your contribution is intentional and you agree to license it under the same terms as the project's license, we've adopted the same lightweight approach that the Linux Kernel [submitting patches process]( https://www.kernel.org/doc/html/latest/process/submitting-patches.html#sign-your-work-the-developer-s-certificate-of-origin>), [Docker](https://github.com/docker/docker/blob/master/CONTRIBUTING.md), and many other projects use: the DCO (Developer Certificate of Origin: https://developercertificate.org/). This is a simple declaration that you wrote the contribution or otherwise have the right to contribute it to Matrix: ``` Developer Certificate of Origin Version 1.1 Copyright (C) 2004, 2006 The Linux Foundation and its contributors. 660 York Street, Suite 102, San Francisco, CA 94110 USA Everyone is permitted to copy and distribute verbatim copies of this license document, but changing it is not allowed. Developer's Certificate of Origin 1.1 By making a contribution to this project, I certify that: (a) The contribution was created in whole or in part by me and I have the right to submit it under the open source license indicated in the file; or (b) The contribution is based upon previous work that, to the best of my knowledge, is covered under an appropriate open source license and I have the right under that license to submit that work with modifications, whether created in whole or in part by me, under the same open source license (unless I am permitted to submit under a different license), as indicated in the file; or (c) The contribution was provided directly to me by some other person who certified (a), (b) or (c) and I have not modified it. (d) I understand and agree that this project and the contribution are public and that a record of the contribution (including all personal information I submit with it, including my sign-off) is maintained indefinitely and may be redistributed consistent with this project or the open source license(s) involved. ``` If you agree to this for your contribution, then all that's needed is to include the line in your commit or pull request comment: ``` Signed-off-by: Your Name ``` We accept contributions under a legally identifiable name, such as your name on government documentation or common-law names (names claimed by legitimate usage or repute). Unfortunately, we cannot accept anonymous contributions at this time. Git allows you to add this signoff automatically when using the `-s` flag to `git commit`, which uses the name and email set in your `user.name` and `user.email` git configs. ## Updating your pull request If you decide to make changes to your pull request - perhaps to address issues raised in a review, or to fix problems highlighted by [continuous integration](#continuous-integration-and-testing) - just add new commits to your branch, and push to GitHub. The pull request will automatically be updated. Please **avoid** rebasing your branch, especially once the PR has been reviewed: doing so makes it very difficult for a reviewer to see what has changed since a previous review. ## Conclusion That's it! Matrix is a very open and collaborative project as you might expect given our obsession with open communication. If we're going to successfully matrix together all the fragmented communication technologies out there we are reliant on contributions and collaboration from the community to do so. So please get involved - and we hope you have as much fun hacking on Matrix as we do!