Setup PDM for GitHub Action

A GitHub Action that installs pdm properly for all Python versions

Why do I need this action?

Nowadays the main reason to use this action is that actions/setup-python doesn't support caching for PDM out of the box while setup-pdm does.

Historically, this action made it easier to use PDM in repos where the Python version in use was older than the Python version required by PDM. PDM requires >=3.8 but works for projects using older versions.

Usage

Include the action in your workflow yaml:

steps:
  - uses: actions/checkout@v4
  - name: Setup PDM
    uses: pdm-project/setup-pdm@v4
    # You are now able to use PDM in your workflow
  - name: Install dependencies
    run: pdm install

You don't need actions/setup-python actually.

Action Inputs

This action supports the following inputs:

Input	Default	Description
python-version	Not specified	Version range or exact version of a Python version to use, using SemVer's version range syntax.
python-version-file	pyproject.toml	File containing the Python version to use. Example: .python-version
architecture	x64	The target architecture (x86, x64) of the Python interpreter.
allow-python-prereleases	false	Allow prerelease versions of Python to be installed.
token	${{ github.token }}	Used to pull python distributions from actions/python-versions. Since there's a default, this is typically not supplied by the user.
version	Not specified	The version of PDM to install, or 'head' to install from the main branch.
prerelease	false	Allow prerelease versions of PDM to be installed
enable-pep582	false	Enable PEP 582 package loading globally.
cache	false	Cache PDM installation.
cache-dependency-path	pdm.lock	The dependency file(s) to cache.
update-python	true	Whether to update the environment with the requested Python

Action Outputs

This action also exposes the following outputs:

Output	Description
python-version	The installed Python or PyPy version. Useful when given a version range as input.
python-path	The absolute path to the Python or PyPy executable.
pdm-version	The installed PDM version.
pdm-bin	The absolute path to the PDM executable.

Caches

This action has a built-in cache support. You can use it like this:

- uses: pdm-project/setup-pdm@v3
  with:
    python-version: 3.9
    cache: true

The default path to calculate the cache key is ./pdm.lock, you can change it by setting the cache-dependency-path input.

Using a list of file paths to cache dependencies

- uses: pdm-project/setup-pdm@v3
  with:
    python-version: 3.9
    cache: true
    cache-dependency-path: |
      ./pdm.lock
      ./pdm.new.lock

Using a glob pattern to cache dependencies

- uses: pdm-project/setup-pdm@v3
  with:
    python-version: 3.9
    cache: true
    cache-dependency-path: '**/pdm.lock'