# Contributing to Compose

Compose is a part of the Docker project, and follows the same rules and
principles. Take a read of [Docker's contributing guidelines](https://github.com/docker/docker/blob/master/CONTRIBUTING.md)
to get an overview.

## TL;DR

Pull requests will need:

 - Tests
 - Documentation
 - [To be signed off](https://github.com/docker/docker/blob/master/CONTRIBUTING.md#sign-your-work)
 - A logical series of [well written commits](https://github.com/alphagov/styleguides/blob/master/git.md)

## Development environment

If you're looking contribute to Compose
but you're new to the project or maybe even to Python, here are the steps
that should get you started.

1. Fork [https://github.com/docker/compose](https://github.com/docker/compose)
   to your username.
2. Clone your forked repository locally `git clone git@github.com:yourusername/compose.git`.
3. You must [configure a remote](https://help.github.com/articles/configuring-a-remote-for-a-fork/) for your fork so that you can [sync changes you make](https://help.github.com/articles/syncing-a-fork/) with the original repository.
4. Enter the local directory `cd compose`.
5. Set up a development environment by running `python setup.py develop`. This
   will install the dependencies and set up a symlink from your `docker-compose`
   executable to the checkout of the repository. When you now run
   `docker-compose` from anywhere on your machine, it will run your development
   version of Compose.

## Submitting a pull request

See Docker's [basic contribution workflow](https://docs.docker.com/project/make-a-contribution/#the-basic-contribution-workflow) for a guide on how to submit a pull request for code or documentation.

## Running the test suite

Use the test script to run linting checks and then the full test suite against
different Python interpreters:

    $ script/test

Tests are run against a Docker daemon inside a container, so that we can test
against multiple Docker versions. By default they'll run against only the latest
Docker version - set the `DOCKER_VERSIONS` environment variable to "all" to run
against all supported versions:

    $ DOCKER_VERSIONS=all script/test

Arguments to `script/test` are passed through to the `nosetests` executable, so
you can specify a test directory, file, module, class or method:

    $ script/test tests/unit
    $ script/test tests/unit/cli_test.py
    $ script/test tests.integration.service_test
    $ script/test tests.integration.service_test:ServiceTest.test_containers

## Finding things to work on

We use a [ZenHub board](https://www.zenhub.io/) to keep track of specific things we are working on and planning to work on. If you're looking for things to work on, stuff in the backlog is a great place to start.

For more information about our project planning, take a look at our [GitHub wiki](https://github.com/docker/compose/wiki).