Switch from Travis CI to GitHub Actions and include Python 3.9 in test matrix

[michael-k]

This requires the coveralls repo token to be available as a secret. You can find the token at https://coveralls.io/github/alexcasalboni/ssm-cache-python. It must be added at https://github.com/alexcasalboni/ssm-cache-python/settings/secrets/actions

[alexcasalboni]

Thanks for opening this PR @michael-k, it looks awesome! 🎉

Could you share any reference to the resulting benefits? I'm personally OK with both tools, and would like to learn more about the differences and trade-offs (if any). Thanks :)

[michael-k]

1. travis-ci.org stopped working on/around 2021-06-15 (you'd have to switch to travis-ci.com) see https://travis-ci.org/github/alexcasalboni/ssm-cache-python

Still working: No longer working:

2. Travis CI GmbH was acquired in 2019. Lots of staff was let go. Personally I have the impression (no hard data) that their service also degraded (uptime, features, …).
3. Github Actions is free for open source projects. Travis CI is also free for OSS, but you'd have to apply somehow, see https://blog.travis-ci.com/2020-11-02-travis-ci-new-billing
   • Lots of projects (boto3 [PR], django/channels, troposphere [PR], SAM CLI [PR], …) moved from Travis CI to Github Actions or somewhere else. But I'm not sure if this is related to the pricing change or anything else.
4. GitHub Actions has more ways to trigger workflows (not relevant for this repo) https://docs.github.com/en/actions/reference/events-that-trigger-workflows

[michael-k]

Here's a good argument (security) against Travis CI: https://twitter.com/peter_szilagyi/status/1437646118700175360

[alexcasalboni]

Ouch! Thanks for sharing 🙏

I promise I'll jump into this after coming back from honeymoon in a couple of weeks!