Contribution Overview

RAIL is a constellation of multiple packages developed publicly on GitHub and welcomes all interested developers, regardless of DESC membership or LSST data rights.

Contributing to RAIL

If you are interested in contributing to RAIL itself, e.g., by adding new algorithms or similar analysis tools, please visit contributing to RAIL

Contributing to rail_projects

If you’re interested in contributing to rail_projects, but don’t know where to start, take a look at the list of issues. Or, create a new issue to suggest a change.

In addition to GitHub, the RAIL team uses the LSSTC Slack workspace for organization. Professional astronomers (including students!) based in the US, Chile, or a French IN2P3 institution are encouraged to join the LSST-DESC to gain access to the #desc-pz-rail channel on the LSSTC Slack workspace.

Those without data rights who wish to gain access to the Slack channel should create an Issue to request that the team leads initiate the process for adding a DESC External Collaborator.

Where to contribute:

In all cases, begin by following the developer installation instructions Developer Installation and follow the contribution workflow instructions below.

Contribution workflow

The rail_projects repository use an issue-branch-review workflow, similar to the standard GitHub Flow. We typically use git as our version control tool, there are many resources available online, but here is a nice cheat sheet created by GitHub.

Issue

When you identify something that should be done, make an issue for it.

Branch

See Developer Installation for installation instructions.

While developing in a branch, don’t forget to pull from main regularly (at least daily) to make sure your work is compatible with other recent changes.

When you’re ready to merge your branch into the main branch, create a pull request (“PR”) in the rail repository you cloned from. GitHub has instructions here.

Several continuous integration checks will be performed for new pull requests. If any of these automatic processes find issues with the code, you should address them in the branch before sending for review. These include unit tests (does the code function correctly), pylint (code style), or coverage (how much code is exercised in unit tests).

Once you are satisfied with your PR, request that other team members review and approve it. You could send the request to someone whom you’ve worked with on the topic, or one of the core maintainers of rail.

Merge

Once the changes in your PR have been approved, these are your next steps:

  1. the author merges the change by selecting “Squash and merge” on the approved pull request

  2. enter closes #[#] in the comment field to close the resolved issue

  3. delete your branch using the button on the merged pull request.

Reviewing a PR

To review a pull request, it’s a good idea to start by pulling the changes and running the unit tests locally. If the continuous integration tests have run successfully, there is good hope that the unit tests will run locally as well!

Check the code for complete and accurate docstrings, sufficient comments, and ensure any instances of #pragma: no cover (excluding the code from unit test coverage accounting) are extremely well-justified.

Feel free to mark the PR with “Request changes” for necessary changes. e.g. writing an exception for an edge case that will break the code, updating names to adhere to the naming conventions, etc.

It is also considered good practice to make suggestions for optional improvements, such as adding a one-line comment before a clever block of code or including a demonstration of new functionality in the example notebooks.

Naming conventions

We follow the pep8 recommendations for naming new modules.

Modules

Modules should use all lowercase, with underscores where it aids the readability of the module name.

Classes

Python classes and so should use the CapWords convention.

Contribution Types

We anticipate a few types of contributions, and provide separate instructions for those workflows: