Change Conda environment via powershell script (for Gitlab-CI)

Question

I am running some automated Python tests with GitLab-CI on a Windows 10 machine. The GitLab-Runner on the machine used to work with executor = "shell" using the simple Windows shell. This recently stopped working (The docs say support for this shell is depreceated) and the only way to get it work again has been to use the powershell instead with adding shell = "powershell" to our config.toml file. For the tests to run, we need to activate a conda environment. Unfortunately, this seems not to work via the powershell script that GitLab-CI creates for the job.

When I open the powershell manually logged in as the user that is executing the gitlab runner jobs, changing conda environments works. I have run conda init powershell and can change the environment with conda activate myenv. Yet, when I include the following in my gitlab-ci.yml file:

script:
  - conda activate myenv
  - conda list

the output from conda list confirms that the environment myenv is not activated and instead the base environment is used.

Also trying the absolute path like this

script:
  - conda activate C:\Users\myuser\Miniconda3\envs\myenv
  - conda list

does not work.

So it seems like I can manually activate the correct conda environment in the powershell, but activating the environment via the powershell script created by GitLab-CI does not work. Is there a fix for this problem? Any help is greatly appreciated.

Answer 1

Looks like gitlab executes each line of the script in a separate subshell. Combine the commands into a single line.

If that doesn't work, most conda commands will accept the name of the environment as parameter -n:

conda list -n myenv
conda install -n myenv PackageName
...

As long as you're just using conda, it shouldn't be necessary to activate the environment.