CONTRIBUTING.md

Contributing to LALSuite

This page outlines the recommended procedure for contributing changes to the LALSuite repository. Please read the introduction to GitLab on git.ligo.org before you start.

Reporting Issues

If you have ligo.org authentication, please report issues directly through gitlab. Otherwise, you can use the service desk address contact+lscsoft-lalsuite-1438-issue-@support.ligo.org to send bug reports by e-mail.

In either case, please include as much detail as possible to reproduce the error, including information about your operating system and the version of each (relevant) component of LALSuite. If possible, please include a brief, self-contained code example that demonstrates the problem.

Note that when an issue is marked as 'confidential', currently this means that most internal users will also not be able to see it, but only a small number of people with reporter, developer or maintainer status.

Contributing code

All contributions to LALSuite code must be made using the fork and merge request workflow, which must then be reviewed by one of the project maintainers.

If you wish to contribute new code, or changes to existing code, please follow this development workflow:

Make a fork (copy) of LALSuite

You only need to do this once

1. Go to the LALSuite repository home page
2. Click on the Fork button, that should lead you here
3. Select the namespace that you want to create the fork in, this will usually be your personal namespace

If you can't see the Fork button, make sure that you are logged in by checking for your account profile photo in the top right-hand corner of the screen.

Clone your fork

Make sure that you have installed and configured git-lfs:

git lfs install

for the management of large files. This is required to successfully build and install your development fork.

Then, clone your fork with

git clone git@git.ligo.org:<namespace>/lalsuite.git

Keeping your fork up to date

Link your clone to the main (upstream) repository so that you can fetch and pull changes, merge them with your clone, and push them to your fork. Do not make changes on your master branch.

1. Link your fork to the main repository:

   cd lalsuite
   git remote add upstream git@git.ligo.org:lscsoft/lalsuite.git

   You need only do this step once.

2. Update your master branch to track changes from upstream:

   git checkout master
   git fetch upstream
   git branch --set-upstream-to upstream/master
   git pull

   You only need to do this step once.

3. Fetch new changes from the upstream repository, merge them with your master branch, and push them to your fork on git.ligo.org:

   git checkout master
   git pull
   git push origin master

4. You can see which remotes are configured using

   git remote -v

   If you have followed the instructions thus far, you should see four lines. Lines one and two begin with origin and reference your fork on git.ligo.org with both fetch and push methods. Lines three and four begin with upstream and refer to the main repository on git.ligo.org with both fetch and push methods.

Making changes

All changes should be developed on a feature branch in order to keep them separate from other work, thus simplifying the review and merge once the work is complete. The workflow is:

1. Create a new feature branch configured to track the master branch:

   git checkout master
   git pull
   git checkout -b my-new-feature upstream/master

   This command creates the new branch my-new-feature, sets up tracking the upstream repository, and checks out the new branch. There are other ways to do these steps, but this is a good habit since it will allow you to fetch and merge changes from upstream/master directly onto the branch.

2. Develop the changes you would like to introduce, using git commit to finalise a specific change. Ideally commit small units of change often, rather than creating one large commit at the end, this will simplify review and make modifying any changes easier.

   Commit messages should be clear, identifying which code was changed, and why. Common practice is to use a short summary line (<50 characters), followed by a blank line, then more information in longer lines.

3. Push your changes to the remote copy of your fork on https://git.ligo.org. The first push of any new feature branch will require the -u/--set-upstream option to push to create a link between your new branch and the origin remote:

   git push --set-upstream origin my-new-feature

   Subsequenct pushes can be made with just:

   git push

4. Keep your feature branch up to date with the upstream repository by doing:

   git checkout master
   git pull
   git checkout my-new-feature
   git rebase upstream/master
   git push -f origin my-new-feature

   This works if you created your branch with the checkout command above. If you forgot to add the upstream/master starting point, then you will need to dig deeper into git commands to get changes and merge them into your feature branch.

   If there are conflicts between upstream changes and your changes, you will need to resolve them before pushing everything to your fork.

Open a merge request

When you feel that your work is finished, you should create a merge request to propose that your changes be merged into the main (upstream) repository.

After you have pushed your new feature branch to origin, you should find a new button on the LALSuite repository home page inviting you to create a merge request out of your newly pushed branch. (If the button does not exist, you can initiate a merge request by going to the Merge Requests tab on your fork website on git.ligo.org and clicking New merge request)

You should click the button, and proceed to fill in the title and description boxes on the merge request page. It is recommended that you check the box to Remove source branch when merge request is accepted; this will result in the branch being automatically removed from your fork when the merge request is accepted.

Once the request has been opened, one of the maintainers will assign someone to review the change. There may be suggestions and/or discussion with the reviewer. These interactions are intended to make the resulting changes better. The reviewer will merge your request.

Once the changes are merged into the upstream repository, you should remove the development branch from your clone using

git branch -d my-new-feature

A feature branch should not be repurposed for further development as this can result in problems merging upstream changes.

Speeding up the continuous integration pipeline

The Gitlab-CI (continuous integration) pipeline runs for all changes to ensure that the software still builds and passes all of the tests. The full pipeline (and even more so the nightly pipeline) takes a long time to carefully go through all of the package builds, but for minor changes to documentation or infrastructure this can be a waste of time and resources.

Sections of the CI pipeline can be skipped by adding special key text to your commit messages as follows:

Commit message text	Action
[skip compiler]	Skip compiler test jobs
[skip conda]	Skip Conda build jobs (and their dependents)
[skip coverage]	Skip coverage jobs
[skip debian]	Skip Debian build jobs (and their dependents)
[skip docs]	Skip documentation jobs
[skip integration]	Skip integration test jobs
[skip lint]	Skip lint jobs
[skip platform]	Skip platform test jobs
[skip rhel]	Skip RHEL build jobs (and their dependents)
[skip wheels]	Skip Python wheel build jobs test jobs

It is important that this feature is not abused, please do not skip any jobs when making library changes.

More Information

More information regarding the usage of GitLab can be found in the main GitLab documentation.