Feature request: Do not fail when caching on non-Python repositories

[kdeldycke]

Description:

I am trying to use setup-python in a non Python repository. But I soon as I activate the cache, it ends up with this error:

Run actions/[email protected]
  with:
    python-version: 3.12
    cache: pip
Installed versions
  Successfully set up CPython (3.12.1)
Error: No file in /home/runner/work/awesome-iam/awesome-iam matched to
[**/requirements.txt or **/pyproject.toml], make sure you have checked out the target repository

Thats because the project I check out just before has no **/requirements.txt or **/pyproject.toml file.

And the reason it has no such file is that the actions/checkout and setup-python steps are located in a reused workflow.

Action version:
[email protected]

Platform:

• Ubuntu
• macOS
• Windows

Runner type:

• Hosted
• Self-hosted

Tools version:
Any version of Python.

Repro steps:

Here is the source code of my reused workflow: https://github.com/kdeldycke/workflows/blob/f50130aabec1fe713a548e3296f723732c79a178/.github/workflows/lint.yaml#L26-L35

And here is the result of this invokation: https://github.com/kdeldycke/awesome-iam/actions/runs/7592900227/job/20682781487#step:3:13

Expected behavior:
I expect setup-python not to fail in the absence of a **/requirements.txt or **/pyproject.toml file.

Actual behavior:
The step fails with the following message:

Run actions/[email protected]
  with:
    python-version: 3.12
    cache: pip
Installed versions
  Successfully set up CPython (3.12.1)
Error: No file in /home/runner/work/awesome-iam/awesome-iam matched to
[**/requirements.txt or **/pyproject.toml], make sure you have checked out the target repository

[kdeldycke]

Maybe this issue will be addressed by:

• Add a new input to skip cache updates #751
• Add cache-save: false option #762

[kdeldycke]

To bypass current setup-python behavior, I created a step that is adding an empty requirements.txt if missing:

      - name: Hack setup-python cache
        # XXX Create an empty requirements.txt if this file (or pyproject.toml) doesn't exist.
        # This work around and issue with setup-python for non-Python projects, which ends up with ends up
        # with this error:
        #
        #   Run actions/[email protected]
        #     with:
        #       python-version: 3.12
        #       cache: pip
        #   Installed versions
        #     Successfully set up CPython (3.12.1)
        #   Error: No file in /home/runner/work/awesome-iam/awesome-iam matched to
        #   [**/requirements.txt or **/pyproject.toml], make sure you have checked out the target repository
        #
        # This has been reported at: https://github.com/actions/setup-python/issues/807
        # In the future this might be addressed by: https://github.com/actions/setup-python/pull/762
        # or https://github.com/actions/setup-python/issues/751
        if: hashFiles('**/requirements.txt', '**/pyproject.toml') == ''
        run: |
          touch ./requirements.txt

Source: kdeldycke/workflows@662a971

[HarithaVattikuti]

Hello @kdeldycke
Thank you for creating this issue. We will investigate it and get back to you as soon as we have some feedback.

[aparnajyothi-y]

Hello @kdeldycke, Thank you once again for creating this issue. We have investigated the issue and actions/setup-python action is trying to find a requirements.txt or pyproject.toml file to cache the Python dependencies, but it's not able to find it. This error is encountered because setup-python is designed to cache Python dependencies and it expects these files to be present in Python projects. If the project is a non Python project and does not have any Python dependencies to cache, no need to activate the cache in setup-python. We can remove the cache: pip line from the workflow file.
However, if we have Python dependencies that need to cache, we need to ensure that the project has a requirements.txt (for pip) or pyproject.toml (for pipenv) file. The actions/setup-python action will then be able to find these files and cache the dependencies.
If you're using a reusable workflow, ensure that the repository being checked out in the actions/checkout step does indeed have these Python dependency files.
Here is a sample workflow snippet for using setup-python:
steps:

• uses: actions/checkout@v4

• uses: actions/[email protected]
  with:
  python-version: 3.12
  If the files do exist in your repository but were not fetched during the actions/checkout step, you could try to adjust this step in your workflow. By default, the actions/checkout action only fetches a single commit. If your files are not in the latest commit, they won't be fetched. Fetch all history by setting fetch-depth: 0 as per this document

• name: Checkout code
  uses: actions/checkout@v2
  with:
  fetch-depth: 0

  Please let us know if any further clarification required.

[kdeldycke]

Thanks @aparnajyothi-y for the reply. What you are describing is how setup-python is currently working. But I think I wasn't clear on my initial request.

What I'm looking for is to discuss the possibility for setup-python to support caching in reuseable workflow, and by extension, support caching of remote requirements.txt files.

[deslaughter]

@aparnajyothi-y This may be a silly question, but why does setup-python require that that checkout use the fetch-depth: 0 option? Checking out the entire history instead of just the last commit adds several minutes to the CI run. It's cheaper to disable the caching provided by setup-python than to use fetch-depth: 0 in my case.

[aparnajyothi-y]

Hello @kdeldycke, setup-python action doesn't directly have any support for caching. However, caching dependencies in GitHub workflows, including Python dependencies specified in a requirements.txt file, can typically be done using the actions/cache action.For reusable workflows, you can define a workflow in one repository and reference that workflow in other repositories. However, the actions/cache action currently has some limitations when used in reusable workflows.

As for caching of remote requirements.txt files, this would require some additional steps in your workflow:

• Fetch the remote requirements.txt file, perhaps using curl or wget.
• Generate a cache key from the contents of the requirements.txt file, such as by hashing the file's contents.
• Use this cache key with the actions/cache action.
  setup-action action itself does not provide a built-in caching mechanism. However, you can use the actions/cache action in conjunction with setup-python to cache dependencies, including Python packages installed with pip.

Here's an example of how you might use actions/cache to cache pip packages:

steps:

• uses: actions/checkout@v2
• uses: actions/setup-python@v2
  with:
  python-version: '3.8'
• name: Cache pip packages
  uses: actions/cache@v2
  with:
  path: ~/.cache/pip
  key: ${{ runner.os }}-pip-${{ hashFiles('**/requirements.txt') }}
  restore-keys: |
  ${{ runner.os }}-pip-
• name: Install dependencies
  run: |
  python -m pip install --upgrade pip
  pip install -r requirements.txt

Hello @deslaughter, The fetch-depth: 0 option in the actions/checkout action is used to fetch all history for all branches and tags. This is often necessary when we need the full git history to perform certain operations, like calculating a version number based on the number of commits, generating a changelog, or similar tasks.
However, as we've noted, fetching the entire history can add time to your CI run. Setup-python doesn't inherently require fetch-depth : 0. The need to fetch all history would be specific to your workflow and the tasks you're performing.
If the workflow doesn't require the full git history, you can use a shallow clone (like fetch-depth :1 to get only the latest commit) to save time and resources. This would not affect the functionality of setup-python, which is primarily concerned with setting up a specific version of Python in the runner environment.

[aparnajyothi-y]

Hello @kdeldycke, please confirm if the above-provided information clarifies your request. Thank you.

[kdeldycke]

@aparnajyothi-y no. Your answer is really low-quality and is just trying to avoid discussing the issue. Are you a LLM-based bot?

[aparnajyothi-y]

Hello @kdeldycke, We have explained the work arounds that we can use with action/setup-python and actions/checkout. If the actual request is to implement this feature from setup-python, it needs more investigation. We will get back to you on this once we got some feedback.
Please feel free to share your thoughts on this.

[kdeldycke]

Hi @aparnajyothi-y. I acknowledge the fact that setup-python is not going forward on that problem and decide to close this issue.

For all others looking forward to have this solved, my advice is to get rid of setup-python altogether and rely exclusively on uv in your CI/CD. With Astral taking over the python-build-standalone project , uv is now strong and smart enough to download an appropriate version for your environment, be it your local machine or GitHub workflows.