Workflows: Prevent merging PRs with needs-rebase or do-not-merge labels

[armsnyder]

Description

This action fails if either needs-rebase or do-not-merge labels are present on the PR.

The benefit is we have a way to communicate that a PR should not be merged (do-not-merge) that has some enforcement with it.

I don't know how useful this is right now, but we can also expound on it to add other label rules, for example a PR must have one of N different labels before it can be merged. It could be useful for PR triaging purposes.

Tested in my fork.

PR Checklist

• Resource attributes match 1:1 the names and structure of the API resource in the GitLab API documentation.
• Examples are updated with:
  • A *.tf file for the resource/s with at least one usage example
  • A *.sh file for the resource/s with an import example (if applicable)
• New resources have at minimum a basic test with three steps:
  • Create the resource
  • Update the attributes
  • Import the resource
• No new //lintignore comments that came from copied code. Linter rules are meant to be enforced on new code.

[timofurrer]

don't know how useful this is right now

Something like that would be very useful even right now, e.g. for #815.

Let's start with these two labels. Or maybe a third one which would indicate that it should only be merged after the next release. Maybe wait-upcoming-release or merge-after-release or something like that.

[armsnyder]

Heh yep, #815 gave me the idea. I think just the one do-not-merge label is ok for now. Juggling lots of different labels with similar meaning can be rough. But yep it's always open for change.

[timofurrer]

Juggling lots of different labels with similar meaning can be rough

Btw. I also think that given the labels meaningful descriptions can help a lot with maintaining them.
Unfortunately, I don't have access to edit them (yet).

[armsnyder]

@timofurrer

Unfortunately, I don't have access to edit them (yet).

Oh no, I didn't realize. 😮 And I agree, descriptions are valuable. We could use something like https://github.com/marketplace/actions/label-syncer if it's easier to check the descriptions into git. Or you can suggest descriptions and I could add them.

[armsnyder]

That wasn't a problem for very long 😆

[timofurrer]

Yes, that's right 💪 😄