Making a new Python library release

This guide shows how to make a new Perfetto Python library release to PyPI.

The package version is derived automatically from the CHANGELOG (the top vX.Y entry maps to the PyPI version 0.X.Y), so there is no separate version-bump step. Publishing is a single stage, driven by the tools/release/release_python.py script.

Prerequisites

• Run the script from the root of the repository.
• A Python virtual environment must exist at .venv (the script uses .venv/bin/python).
• A clean git working directory (no uncommitted changes).
• PyPI credentials: the username is __token__. For the password (API token), find "Perfetto PyPi API Key" on http://go/valentine.

Publishing

1. Pick the release commit to publish from — normally the vX.Y tag commit. For example:

COMMIT=$(git rev-parse v56.0^{commit})

2. Run the release script, passing that commit:

tools/release/release_python.py --publish --commit "$COMMIT"

The script will then perform the following steps:

• Checkout: It will check out the specified commit.
• Build & Publish: It will temporarily update the download_url in python/setup.py to that commit's source archive, build the package (the version is read from the CHANGELOG), and, after you confirm, upload it to PyPI. You will be prompted for your PyPI credentials.
• Cleanup: It will remove the temporary build artifacts and restore python/setup.py.
• Final URL Update: After publishing, the script will prompt you for a new branch name. It will then create a new commit on that branch that updates the download_url in python/setup.py to point to the commit from the --commit argument.

3. Once the script completes, push the new branch for the download_url update and create a pull request. After this final PR is landed, the release is complete.