Ansible collections and venv

I work on a large number of collections and in order to test them properly, I’ve to switch between the Python versions and the associated Pypi dependencies. Nothing special here, this is pretty much the life of all of us who work on the Ansible collections.

Initially, I was maintaining a set of clean Python virtual environments. Basically, one per version of Python. And I was juggling between then. Sadly, it’s easy to lose track of what’s going one. Every time I was switching to a different collection, I had to pull a new set of dependencies and the order was never the same.

I ended up being actually frustrated by the wasted time spent on looking at the pip freeze output to understand some oddity. It’s so easy to mess up the whole cathedral. A good example is that use a lot pip install -e git/something to install a local copy of a library. And as a result, any change there can potentially nuke the fragile little creature.

So now, I use another approach. I’ve got a script that spawn a virtual environment on the light, pull the right dependencies and initialize the shell. It may sounds like a trivial thing, but I actually use it several times every days and I don’t call pip freeze that much.

For instance if I need to work with Ansible 2.10 and Python 3.10, I just need to do:

$ cd .ansible/collections/ansible_collections/vmware/vmware_rest
$ source ~/bin/ 3.10 stable-2.10

and I’m ready to run ansible-playbook or ansible-test in my clean environment. And when I want to reinitialize the venv, I’ve just to remove the venv directory.

The script is here and depends on FishShell, my favorite Shell.