# Contributing

pyLXD development is done on Github. Pull Requests and Issues should be filed there. We try and respond to PRs and Issues within a few days.

If you would like to contribute major features or have big ideas, it’s best to post at the Linux Containers disucssion forum to discuss your ideas before submitting PRs. If you use `[pylxd]` in the title, it’ll make it clearer.

## Adding a Feature or Fixing a Bug

The main steps are:

1. There needs to be a bug filed on the Github repository. This is also for a feature, so it’s clear what is being proposed prior to somebody starting work on it.

2. The pyLXD repository must be forked on Github to the developer’s own account.

3. The developer should create a personal branch, with either:

   - feature/name-of-feature
   - bug/number/descriptive-name-of-bug

   This can be done with `git checkout -b feature/name-of-feature` from the master branch.

4. Work on that branch, push to the personal GitHub repository and then create a Pull Request. It’s a good idea to create the Pull Request early, particularly for features, so that it can be discussed and help sought (if needed).

5. When the Pull Request is ready it will then be merged.

6. At regular intervals the pyLXD module will be released to PyPi with the new features and bug fixes.

## Requirements to merge a Pull Request (PR)

In order for a Pull Request to be merged the following criteria needs to be met:

1. All of the commits in the PR need to be signed off using the ‘-s’ option with git commit. This is a requirement for all projects in the Github Linux Containers projects space.
2. Unit tests are required for the changes. These are in the `pylxd/tests` directory and follow the same directory structure as the module.
3. The unit test code coverage for the project shouldn’t drop. This means that any lines that aren’t testable (for good reasons) need to be explicitly excluded from the coverage using `# NOQA` comments.
4. If the feature/bug fix requires integration test changes, then they should be added to the `integration` directory.
5. If the feature/bug fix changes the API then the documentation in the `doc/source` directory should also be updated.
6. If the contributor is new to the project, then they should add their name/details to the `CONTRIBUTORS.rst` file in the root of the repository as part of the PR.

Once these requirements are met, the change will be merged to the repository. At this point, the contributor should then delete their private branch.

## Code standards

pyLXD follows PEP 8 as closely as practical. To check your compliance, use the pep8 tox target:

    tox -e pep8

Note

if this fails then the code will not be merged. If there is a good reason for a PEP8 non-conformance, then a `# NOQA` comment should be added to the relevant line(s).

## Testing

Testing pyLXD is in 3 parts:

1. Conformance with PEP 8, using the `tox -e pep8` command.
2. Unit tests using `tox -e py27` and `tox -e py3`.
3. Integration tests using the `run_integration_tests` script in the root of the repository.

Note

all of the tests can be run by just using the `tox` command on it’s own, with the exception of the integration tests. These are not automatically run as they require a working LXD environment.

All of the commands use the Tox automation project to run tests in a sandboxed environment. On Ubuntu this is installed using:

    sudo apt install python-tox

### Unit Testing

pyLXD tries to follow best practices when it comes to testing. PRs are gated by Travis CI and CodeCov. It’s best to submit tests with new changes, as your patch is unlikely to be accepted without them.

To run the tests, you should use Tox:

    tox

### Integration Testing

Integration testing requires a running LXD system. At present this is not performed by the CI system, although this is intended at some point in the future. Integration testing should be performed prior to merging a PR.

Currently, there are two variants of the script to run integration tests:

1. `run_integration_tests-16-04`
2. `run_integration_tests-18-04`

The default is `run_integration_tests-18-04`, which is symlinked to `run_integration_tests`. This is because the default is to test on Ubuntu Bionic, with Ubuntu Xenial (16.04) for maintenance purposes.

Note

A script to automate running the integration tests needs to be added.

Some hints on how to run the integration tests:

1. On Ubuntu it’s probably easiest to use the Multipass snap.
2. Launch an LTS instance using `multipass launch -n foo`
3. Shell into the instance: `multipass exec foo -- bash`
4. Install tox and python2.7: `sudo apt install python-tox python-2.7`
5. Clone the branch from the PR (or otherwise copy the repo into the machine)
6. Configure LXD using `lxd init` – follow the prompts provided.
7. Run the integration tests.