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'