Refactor module_utils/crypto.py

[felixfontein]

SUMMARY

Expands the large monolithic plugins/module_utils/crypto.py into a Python package plugins/module_utils/crypto/ with multiple smaller files.

This should not change functionality at all (except fix a tiny bug in x509_crl.py I found while changing this). CI should check essentially everything, except ecs_certificate (and the ECS part of x509_certificate) - @ctrufan can you test it?

I've used pylint and flake8 to check for errors (and clean up unnecessary imports), so the change should be pretty safe.

Fixes #16.

CC @MarkusTeufelberger @puiterwijk @Spredzy @Shaps @ctrufan

ISSUE TYPE

• Bugfix Pull Request
• Feature Pull Request

COMPONENT NAME

plugins/module_utils/crypto.py

[felixfontein]

(Unstable CI is caused by #23 and unrelated to this PR.)

[felixfontein]

I moved some generic file I/O methods (load_file_if_exists and write_file) into a new Python module plugins/module_utils/io.py. This makes them easier to use without also having to include the pyOpenSSL / cryptography feature detection.

I also added a new support function for obtaining the serial number of a cryptography certificate, since that changed in cryptography 1.4. Instead of repeating the same try/except in different modules, there's now one common utility function for that.

[felixfontein]

I've added some compatibility code to module_utils/crypto/__init__.py. With this, even existing modules and existing code depending on module_utils/crypto.py should work without change - well, should, assuming ansible/ansible#68872 wouldn't be there. But once that's fixed, it will work :)

[felixfontein]

(The current error in macOS is caused by pyca/cryptography#5215)

[felixfontein]

@MarkusTeufelberger @puiterwijk @Spredzy @Shaps @ctrufan I would be really happy if you could review this PR :)

[ctrufan]

Apologies, I've been super busy - I should have a chance to retest the ecs_certificate module some time this week. I'll see if I can find time this weekend to review the PR as well.

[felixfontein]

The problem with cryptography on old macOS versions has been resolved with the release of cryptography 2.9.2. Now it's back to "unstable" as before.

[MarkusTeufelberger]

Looks good to me, let's move this forward. Thanks for the work, Felix!

[felixfontein]

I'll merge this now, so work can continue ;) @MarkusTeufelberger thanks for checking this! @ctrufan the change should be pretty safe for the ecs_* modules, but it probably won't hurt when you test it at some point. You should definitely test it before we release 1.0.0 of the collection anyway ;)