1# How to contribute
2
3We definitely welcome your patches and contributions to gRPC! Please read the gRPC
4organization's [governance rules](https://github.com/grpc/grpc-community/blob/master/governance.md)
5and [contribution guidelines](https://github.com/grpc/grpc-community/blob/master/CONTRIBUTING.md) before proceeding.
6
7If you are new to github, please start by reading [Pull Request
8howto](https://help.github.com/articles/about-pull-requests/)
9
10If you are looking for features to work on, please filter the issues list with the label ["disposition/help wanted"](https://github.com/grpc/grpc/issues?q=label%3A%22disposition%2Fhelp+wanted%22).
11Please note that some of these feature requests might have been closed in the past as a result of them being marked as stale due to there being no activity, but these are still valid feature requests.
12
13## Legal requirements
14
15In order to protect both you and ourselves, you will need to sign the
16[Contributor License
17Agreement](https://identity.linuxfoundation.org/projects/cncf).
18
19## Cloning the repository
20
21Before starting any development work you will need a local copy of the gRPC repository.
22Please follow the instructions in [Building gRPC C++: Clone the repository](BUILDING.md#clone-the-repository-including-submodules).
23
24## Building & Running tests
25
26Different languages use different build systems. To hide the complexity
27of needing to build with many different build systems, a portable python
28script that unifies the experience of building and testing gRPC in different
29languages and on different platforms is provided.
30
31To build gRPC in the language of choice (e.g. `c++`, `csharp`, `php`, `python`, `ruby`, ...)
32- Prepare your development environment based on language-specific instructions in `src/YOUR-LANGUAGE` directory.
33- The language-specific instructions might involve installing C/C++ prerequisites listed in
34  [Building gRPC C++: Prerequisites](BUILDING.md#pre-requisites). This is because gRPC implementations
35  in this repository are using the native gRPC "core" library internally.
36- Run
37  ```
38  python tools/run_tests/run_tests.py -l YOUR_LANGUAGE --build_only
39  ```
40- To also run all the unit tests after building
41  ```
42  python tools/run_tests/run_tests.py -l YOUR_LANGUAGE
43  ```
44
45You can also run `python tools/run_tests/run_tests.py --help` to discover useful command line flags supported. For more details,
46see [tools/run_tests](tools/run_tests) where you will also find guidance on how to run various other test suites (e.g. interop tests, benchmarks).
47
48## Generated project files
49
50To ease maintenance of language- and platform- specific build systems, many
51projects files are generated using templates and should not be edited by hand.
52Run `tools/buildgen/generate_projects.sh` to regenerate.  See
53[templates](templates) for details.
54
55As a rule of thumb, if you see the "sanity tests" failing you've most likely
56edited generated files or you didn't regenerate the projects properly (or your
57code formatting doesn't match our code style).
58
59## Guidelines for Pull Requests
60How to get your contributions merged smoothly and quickly.
61
62- Create **small PRs** that are narrowly focused on **addressing a single
63  concern**.  We often times receive PRs that are trying to fix several things
64  at a time, but only one fix is considered acceptable, nothing gets merged and
65  both author's & review's time is wasted.  Create more PRs to address different
66  concerns and everyone will be happy.
67
68- For speculative changes, consider opening an issue and discussing it first.
69  If you are suggesting a behavioral or API change, consider starting with a
70  [gRFC proposal](https://github.com/grpc/proposal).
71
72- Provide a good **PR description** as a record of **what** change is being made
73  and **why** it was made.  Link to a GitHub issue if it exists.
74
75- Don't fix code style and formatting unless you are already changing that line
76  to address an issue.  PRs with irrelevant changes won't be merged.  If you do
77  want to fix formatting or style, do that in a separate PR.
78
79- If you are adding a new file, make sure it has the copyright message template
80  at the top as a comment. You can copy over the message from an existing file
81  and update the year.
82
83- Unless your PR is trivial, you should expect there will be reviewer comments
84  that you'll need to address before merging.  We expect you to be reasonably
85  responsive to those comments, otherwise the PR will be closed after 2-3 weeks
86  of inactivity.
87
88- If you have non-trivial contributions, please consider adding an entry to [the
89  AUTHORS file](https://github.com/grpc/grpc/blob/master/AUTHORS) listing the
90  copyright holder for the contribution (yourself, if you are signing the
91  individual CLA, or your company, for corporate CLAs) in the same PR as your
92  contribution.  This needs to be done only once, for each company, or
93  individual. Please keep this file in alphabetical order.
94
95- Maintain **clean commit history** and use **meaningful commit messages**.
96  PRs with messy commit history are difficult to review and won't be merged.
97  Use `rebase -i upstream/master` to curate your commit history and/or to
98  bring in latest changes from master (but avoid rebasing in the middle of
99  a code review).
100
101- Keep your PR up to date with upstream/master (if there are merge conflicts,
102  we can't really merge your change).
103
104- If you are regenerating the projects using
105  `tools/buildgen/generate_projects.sh`, make changes to generated files a
106  separate commit with commit message `regenerate projects`.  Mixing changes
107  to generated and hand-written files make your PR difficult to review.
108  Note that running this script requires the installation of Python packages
109  `pyyaml` and `mako` (typically installed using `pip`) as well as a recent
110  version of [`go`](https://golang.org/doc/install#install).
111
112- **All tests need to be passing** before your change can be merged.
113  We recommend you **run tests locally** before creating your PR to catch
114  breakages early on (see [tools/run_tests](tools/run_tests).  Ultimately, the
115  green signal will be provided by our testing infrastructure.  The reviewer
116  will help you if there are test failures that seem not related to the change
117  you are making.
118
119- Exceptions to the rules can be made if there's a compelling reason for doing
120  so.
121
122## Obtaining Commit Access
123We grant Commit Access to contributors based on the following criteria:
124* Sustained contribution to the gRPC project.
125* Deep understanding of the areas contributed to, and good consideration of various reliability, usability and performance tradeoffs.
126* Contributions demonstrate that obtaining Commit Access will significantly reduce friction for the contributors or others.
127
128In addition to submitting PRs, a Contributor with Commit Access can:
129* Review PRs and merge once other checks and criteria pass.
130* Triage bugs and PRs and assign appropriate labels and reviewers.
131
132### Obtaining Commit Access without Code Contributions
133The [gRPC organization](https://github.com/grpc) is comprised of multiple repositories and commit access is usually restricted to one or more of these repositories. Some repositories such as the [grpc.github.io](https://github.com/grpc/grpc.github.io/) do not have code, but the same principle of sustained, high quality contributions, with a good understanding of the fundamentals, apply.
134
135