contextvars requirement

[yangskyboxlabs]

I'd like to understand the context which leads salt to continue to carry a dependency on contextvars from PyPI.

base.txt simply notes that salt-ssh requires it, but I see no unusual usage of contextvars in the salt-ssh stack contained within Salt.

[lkubb]

Salt-SSH works by packing Salt and dependencies into a so-called thin tarball. Essentially, it copies Salt + its hard dependencies from the master into a tar archive that is sent to the target. In case Salt-SSH connects to a target with a Python version of 3.6 or lower, it needs a contextvars module that can be packed into the thin tar.

To discover the sources, salt.utils.thin imports the module and references <mod>.__file__. The stdlib contextvars imports from _contextvars itself, which does not work with this mechanism, while the library is self-contained.

[yangskyboxlabs]

Thanks! That was super useful. This gives me a couple viable routes to explore with our current plan to build some tooling that requires tight integration with a masterless salt minion.