# Contributing to matrix-rust-sdk ## Chat rooms In addition to our [main Matrix room], we have a development room at [#matrix-rust-sdk-dev:flipdot.org]. Please use it to discuss potential changes, the overall direction of development and related topics. [main Matrix room]: https://matrix.to/#/#matrix-rust-sdk:matrix.org [#matrix-rust-sdk-dev:flipdot.org]: https://matrix.to/#/#matrix-rust-sdk-dev:flipdot.org ## Testing You can run most of the tests that also happen in CI also using `cargo xtask ci`. This needs a few dependencies to be installed, as it also runs automatic WASM tests: ```bash rustup component add clippy cargo install cargo-nextest typos-cli wasm-pack ``` If you want to execute only one part of CI, there are a few sub-commands (see `cargo xtask ci --help`). Some tests are not automatically run in `cargo xtask ci`, for example the integration tests that need a running synapse instance. These tests reside in `./testing/matrix-sdk-integration-testing`. See its [README](./testing/matrix-sdk-integration-testing/README.md) to easily set up a synapse for testing purposes. ## Pull requests Ideally, a PR should have a *proper title*, with *atomic logical commits*, and each commit should have a *good commit message*. A *proper PR title* would be a one-liner summary of the changes in the PR, following the same guidelines of a good commit message, including the area/feature prefix. Something like `FFI: Allow logs files to be pruned.` would be a good PR title. (An additional bad example of a bad PR title would be `mynickname/branch name`, that is, just the branch name.) # Writing changelog entries We aim to maintain clear and informative changelogs that accurately reflect the changes in our project. This guide will help you write useful changelog entries using git-cliff, which fetches changelog entries from commit messages. ## Commit message format Commit messages should be formatted as Conventional Commits. In addition, some git trailers are supported and have special meaning (see below). ### Conventional commits Conventional Commits are structured as follows: ``` (): ``` The type of changes which will be included in changelogs is one of the following: * `feat`: A new feature * `fix`: A bug fix * `doc`: Documentation changes * `refactor`: Code refactoring * `perf`: Performance improvements * `ci`: Changes to CI configuration files and scripts The scope is optional and can specify the area of the codebase affected (e.g., olm, cipher). ### Changelog trailer In addition to the Conventional Commit format, you can use the `Changelog` git trailer to specify the changelog message explicitly. When that trailer is present, its value will be used as the changelog entry instead of the commit's leading line. The `Breaking-Change` git trailer can be used in a similar manner if the changelog entry should be marked as a breaking change. #### Example commit message ``` feat: Add a method to encode Ed25519 public keys to Base64 This patch adds the `Ed25519PublicKey::to_base64()` method, which allows us to stringify Ed25519 and thus present them to users. It's also commonly used when Ed25519 keys need to be inserted into JSON. Changelog: Add the `Ed25519PublicKey::to_base64()` method which can be used to stringify the Ed25519 public key. ``` In this commit message, the content specified in the `Changelog` trailer will be used for the changelog entry. Be careful to add at least one whitespace after new lines to create a paragraph. ### Security fixes Commits addressing security vulnerabilities must include specific trailers for vulnerability metadata. These commits are required to include at least the `Security-Impact` trailer to indicate that the commit is a security fix. Security issues have some additional git-trailers: * `Security-Impact`: The magnitude of harm that can be expected, i.e. low/moderate/high/critical. * `CVE`: The CVE that was assigned to this issue. * `GitHub-Advisory`: The GitHub advisory identifier. Example: ``` fix(crypto): Use a constant-time Base64 encoder for secret key material This patch fixes a security issue around a side-channel vulnerability[1] when decoding secret key material using Base64. In some circumstances an attacker can obtain information about secret secret key material via a controlled-channel and side-channel attack. This patch avoids the side-channel by switching to the base64ct crate for the encoding, and more importantly, the decoding of secret key material. Security-Impact: Low CVE: CVE-2024-40640 GitHub-Advisory: GHSA-j8cm-g7r6-hfpq Changelog: Use a constant-time Base64 encoder for secret key material to mitigate side-channel attacks leaking secret key material. ``` ## Review process To streamline the review process and make it easier for maintainers to review your contributions, follow these basic rules: 1. Do not force push after a review has started. This helps maintainers track incremental changes without confusion and makes it easier to follow the evolution of the code. 2. Do not mix moves and refactoring with functional changes. Keep these in separate commits for clarity. This ensures that the purpose of each commit is clear and easy to review. 3. Each commit must compile. If commits don’t compile, git bisect becomes unusable, which hampers the debugging process and makes it harder to identify the source of issues. 4. Commits should only introduce test failures if they are proving that a bug exists. New features should never introduce test failures. Test failures should only be used to demonstrate existing bugs, not as part of adding new functionality. 5. Keep PRs on topic and small. Large PRs are harder to review and more prone to delays. Create small, focused commits that address a single topic. Use a combination of [git add] -p or git checkout -p to split changes into logical units. This makes your work easier to review and reduces the chance of introducing unrelated changes. [git add]: https://git-scm.com/docs/git-add#Documentation/git-add.txt---patch [git checkout]: https://git-scm.com/docs/git-checkout#Documentation/git-checkout.txt---patch ### Addressing review comments using fixup commits So you posted a PR and the maintainers aren't quite happy with it. Here are some guidelines to make the maintainers life easier and increase the chances that your PR will be reviewed swiftly. 1. Use [fixup] commits. When addressing reviewer feedback, you can create fixup commits. These commits mark your changes as corrections of specific previous commits in the PR. Example: ```bash git commit --fixup= ``` This command creates a new commit that refers to an existing one, making it easier to rebase and squash later while showing reviewers the history of fixes. For extra points, link to the fixup commit in the thread where the change was requested. 2. After all requested changes were addressed, feel free to re-request a review. People might not notice that all changes were addressed. 3. Once the PR has been approved, rebase your PR to squash all the fixup commits, the [autosquash] option can help with this. ```bash git rebase main --interactive --autosquash ``` [fixup]: https://git-scm.com/docs/git-commit#Documentation/git-commit.txt---fixupamendrewordltcommitgt [autosquash]: https://git-scm.com/docs/git-rebase#Documentation/git-rebase.txt---autosquash ## 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](https://www.kernel.org/doc/Documentation/SubmittingPatches), [Docker](https://github.com/docker/docker/blob/master/CONTRIBUTING.md), and many other projects use: the DCO ([Developer Certificate of Origin](http://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 ``` 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. If you forgot to sign off your commits before making your pull request and are on Git 2.17+ you can mass signoff using rebase: ``` git rebase --signoff origin/main ``` ## Tips for working on the `matrix-rust-sdk` with specific IDEs * [RustRover](https://www.jetbrains.com/rust/) will attempt to sync the project with all features enabled, causing an error in `matrix-sdk` ("only one of the features 'native-tls' or 'rustls-tls' can be enabled"). To work around this, open `crates/matrix-sdk/Cargo.toml` in RustRover and uncheck one of the `native-tls` or `rustls-tls` feature definitions: ![Screenshot of RustRover](.img/rustrover-disable-feature.png)