podman-compose/CONTRIBUTING.md

# Contributing to podman-compose

## Who can contribute?

- Users that found a bug
- Users that want to propose new functionalities or enhancements
- Users that want to help other users to troubleshoot their environments
- Developers that want to fix bugs
- Developers that want to implement new functionalities or enhancements

## Branches

Please request your pull request to be merged into the `devel` branch.
Changes to the `stable` branch are managed by the repository maintainers.

## Development environment setup

Note: Some steps are OPTIONAL but all are RECOMMENDED.

1. Fork the project repository and clone it
```shell
$ git clone https://github.com/USERNAME/podman-compose.git
$ cd podman-compose
```
1. (OPTIONAL) Create a Python virtual environment. Example using [virtualenv wrapper](https://virtualenvwrapper.readthedocs.io/en/latest/):
```shell
mkvirtualenv podman-compose
```
2. Install the project runtime and development requirements
```shell
$ pip install '.[devel]'
```
3. (OPTIONAL) Install `pre-commit` git hook scripts (https://pre-commit.com/#3-install-the-git-hook-scripts)
```shell
$ pre-commit install
```
4. Create a new branch, develop and add tests when possible
5. Run linting and testing before committing code. Ensure all the hooks are passing.
```shell
$ pre-commit run --all-files
```
6. Run code coverage
```shell
coverage run --source podman_compose -m unittest pytests/*.py
python -m unittest tests/*.py
coverage combine
coverage report
coverage html
```
7. Commit your code to your fork's branch.
   - Make sure you include a `Signed-off-by` message in your commits. Read [this guide](https://github.com/containers/common/blob/main/CONTRIBUTING.md#sign-your-prs) to learn how to sign your commits
   - In the commit message reference the Issue ID that your code fixes and a brief description of the changes. Example: `Fixes #516: Allow empty network`
8. Open a pull request to `containers/podman-compose:devel` and wait for a maintainer to review your work.

## Adding new commands

To add a command, you need to add a function that is decorated with `@cmd_run`.

The decorated function must be declared `async` and should accept two arguments: The compose instance and the
command-specific arguments (resulted from the Python's `argparse` package).

In this function, you can run Podman (e.g. `await compose.podman.run(['inspect', 'something'])`), access `compose.pods`,
`compose.containers` etc.

Here is an example:

```
@cmd_run(podman_compose, 'build', 'build images defined in the stack')
async def compose_build(compose, args):
    await compose.podman.run(['build', 'something'])
```

## Command arguments parsing

To add arguments to be parsed by a command, you need to add a function that is decorated with `@cmd_parse` which accepts
the compose instance and the command's name (as a string list or as a single string).

The decorated function should accept a single argument: An instance of `argparse`.

In this function, you can call `parser.add_argument()` to add a new argument to the command.

Note you can add such a function multiple times.

Here is an example:

```
@cmd_parse(podman_compose, 'build')
def compose_build_parse(parser):
    parser.add_argument("--pull",
        help="attempt to pull a newer version of the image", action='store_true')
    parser.add_argument("--pull-always",
        help="attempt to pull a newer version of the image, Raise an error even if the image is present locally.", action='store_true')
```

NOTE: `@cmd_parse` should be after `@cmd_run`

## Calling a command from another one

If you need to call `podman-compose down` from `podman-compose up`
do something like:

```
@cmd_run(podman_compose, 'up', 'up desc')
async def compose_up(compose, args):
    await compose.commands['down'](compose, args)
    # or
    await compose.commands['down'](argparse.Namespace(foo=123))
```


## Missing Commands (help needed)
```
  bundle             Generate a Docker bundle from the Compose file
  create             Create services
  events             Receive real time events from containers
  images             List images
  rm                 Remove stopped containers
  scale              Set number of containers for a service
  top                Display the running processes
```