Release procedure¶

This page gives an overview of how technote releases are made. This information is only useful for maintainers.

technote’s releases are largely automated through GitHub Actions (see the ci.yaml workflow file for details). When a semantic version tag is pushed to GitHub, technote is released to PyPI with that version. Similarly, documentation is built and pushed for each version (see https://technote.lsst.io/v).

Regular releases¶

Regular releases happen from the main branch after changes have been merged. From the main branch you can release a new major version (X.0.0), a new minor version of the current major version (X.Y.0), or a new patch of the current major-minor version (X.Y.Z). See Backport releases to patch an earlier major-minor version.

Release tags are semantic version identifiers following the PEP 440 specification.

1. Change log and documentation¶

Each PR should include updates to the change log. If the change log or documentation needs additional updates, now is the time to make those changes through the regular branch-and-PR development method against the main branch.

In particular, replace the “Unreleased” section headline with the semantic version and date. See Updating the change log in the Developer guide for details.

2. GitHub release and tag¶

Use GitHub’s Release feature to create releases and their corresponding Git tags.

Specify a tag from the appropriate branch (typically main). This tag’s name is PEP 440 and is usually formatted at X.Y.Z (without a v prefix).
For the release name, repeat the version string.
Fill in the release notes, copied from the release notes. You can use GitHub’s change log feature to additionally generate a list of PRs included in the release.

The tag must follow the PEP 440 specification since technote uses setuptools_scm to set version metadata based on Git tags. In particular, don’t prefix the tag with v.

The ci.yaml GitHub Actions workflow uploads the new release to PyPI and documentation to https://technote.lsst.io.

Backport releases¶

The regular release procedure works from the main line of development on the main Git branch. To create a release that patches an earlier major or minor version, you need to release from a release branch.

Creating a release branch¶

Release branches are named after the major and minor components of the version string: X.Y. If the release branch doesn’t already exist, check out the latest patch for that major-minor version:

git checkout X.Y.Z
git checkout -b X.Y
git push -u

Developing on a release branch¶

Once a release branch exists, it becomes the “main” branch for patches of that major-minor version. Pull requests should be based on, and merged into, the release branch.

If the development on the release branch is a backport of commits on the main branch, use git cherry-pick to copy those commits into a new pull request against the release branch.

Releasing from a release branch¶

Releases from a release branch are equivalent to regular releases, except that the release branch takes the role of the main branch.