setup-python overrides PK_CONFIG_PATH

[fizyk]

Description:
I'm attempting to run tests on MacOs that require mysqlclient installed. Version 2.2 of mysqlclient relies on pkg-config, runs pkg-config --exists mysqlclient during installation.
However even if I point PK_CONFIG_PATH to the mysqlclient pk config configuration, setup-python overrides it's contents, which makes the mysqlclient installation fail on macos.

This issue is non existing on ubuntu

Action version:
v4

Platform:

• Ubuntu
• macOS
• Windows

Runner type:

• Hosted
• Self-hosted

Tools version:
Python (Any version)
mysqlclient 2.2.0

Repro steps:

  tests-mysqlient-macosx:
    runs-on: macos-latest
    steps:
    - uses: actions/checkout@v4
    - uses: ankane/setup-mysql@v1
      with:
        mysql-version: 8.0
    - name: Set up Python 3.11
      uses: actions/setup-python@v4
      with:
        python-version: 3.11
    - name: Update PKG_CONFIG_PATH
      run: echo "PKG_CONFIG_PATH=$PKG_CONFIG_PATH:/usr/local/opt/mysql@8.0/lib/pkgconfig" >> "$GITHUB_ENV"
    - name: Check MySQL Version
      run: mysqld --version
    - name: Check pkg-config --exists mysqlclient
      run: pkg-config --exists mysqlclient
    - name: Set up Python 3.11
      uses: actions/setup-python@v4
      with:
        python-version: 3.11
    - name: Install mysqlclient
      run: pip install mysqlclient==2.2.0

Expected behavior:
Installation succedes,

Actual behavior:
Installation fails on pkg-config being unable to read mysqlclient configuration

[fizyk]

run with reproduced steps: https://github.com/ClearcodeHQ/pytest-mysql/actions/runs/6572608008
https://github.com/ClearcodeHQ/pytest-mysql/blob/f34496e7178c1740483ae8ba1953df9daee8e298/.github/workflows/tests.yml#L123

[dmitry-shibanov]

Hello @fizyk. Thank you for your report. You can try to use update-environment input. You can take a look at this example

[fizyk]

@dmitry-shibanov thank you, that seems to be working around the issue, however, I think it would be also better if setup-python hadn't overridden the PK_CONFIG_PATH if it existed prior to running actions/setup-python 🤔
I'm afraid I might end sometimes with manually glued PK_CONFIG_PATH later if it'll be needed to also have PK_CONFIG_PATH from setup-python 🤔

It looks like the actions/core packages only allow to add variable values, https://github.com/actions/toolkit/blob/master/packages/core/src/core.ts#L39

With the exception of PATH: there's addPath functionality in core https://github.com/actions/toolkit/blob/main/packages/core/src/core.ts#L107 not sure if it would be possible for the team responsible for core to add also more general that could cover PK_CONFIG_PATH 🤔

[fizyk]

Last thing, switching off the update-environment flag, also skips the PATH envvar update, which means I'll definitely need to update that manually, if I'll go that way.

[fizyk]

I have worked around this problem with something like this:
https://github.com/fizyk/actions-reuse/pull/139/files#diff-1db8f75d453bbec1df290471bddf711c2b236fa387b1030d308c44dae6d8e8e7R27

[jbcpollak]

I just ran into this bug as well

[priyagupta108]

Hi 👋 ,
Sorry for the delayed response,
The setup-python action overrides PKG_CONFIG_PATH to ensure that the environment variable points to the correct location for Python's package configuration files. This is done to make sure that any build or installation process that relies on pkg-config can locate the necessary configuration files for the specific Python version being set up.
To prioritize your path, explicitly set the PKG_CONFIG_PATH environment variable in the steps after setup-python. For more details, refer to the documentation.
Alternatively, you can use the update-environment flag provided by setup-python. This flag determines whether the action should update the environment variables. You can look at this example.
I hope this helps resolve the problem.

[fizyk]

@priyagupta108 it doesn't, but as I wrote a year ago, I worked around the issue (although that's not too nice) which is more-or-less what you wrote here:

To prioritize your path, explicitly set the PKG_CONFIG_PATH environment variable in the steps after setup-python. For more details, refer to the documentation. Preserving priority for PKG_CONFIG_PATH set by setup-python

So.... if no change is expected in the way PKG_CONFIG_PATH is being set by setup-python, then I think it can be closed.