Skip push CI for most branches

[djc]

My impression is that the common practice of running CI for both push and pull_request can be pretty expensive/slow while adding almost no value. Restrict branch CI to main and branches prefixed with rel- or ci/.

[ctz]

Suggested change

	pull_request:
	pull_request:
	workflow_dispatch:

This would mean, in the case where some maintainer really does want to run CI for something without opening a PR, they can do that by pushing the branch and then running it manually (this enables the UI for that).

[cpu]

Manually invoking each CI job for each branch push is a very unappealing workflow to me :-/

[cpu]

Restrict branch CI to main and branches prefixed with rel- or ci/.

Do you plan to do this in the other repos, e.g. rustls/rustls? I think it would be valuable to do this consistently, at least in the magic prefix/suffix to get it to happen for a branch push intentionally. E.g. rustls-platform-verifier is using *_dev, can we standardize on that?

I personally don't find it too expensive/slow (especially with cancel-in-progress), and I do appreciate being able to run CI easily before opening a PR so I can make sure it's green before notifying anyone. On the other hand, needing to know a magic suffix/prefix per-repo is annoying and I end up duplicating my branches with different names and having to check the .yml file.

[djc]

Restrict branch CI to main and branches prefixed with rel- or ci/.

Do you plan to do this in the other repos, e.g. rustls/rustls? I think it would be valuable to do this consistently, at least in the magic prefix/suffix to get it to happen for a branch push intentionally. E.g. rustls-platform-verifier is using *_dev, can we standardize on that?

Would @ctz's suggestion of adding workflow_dispatch alleviate your concerns? Sounds like that might be helpful.

[cpu]

Would @ctz's suggestion of adding workflow_dispatch alleviate your concerns? Sounds like that might be helpful.

I don't think it would. It's even more friction than having to name your branch correctly IMO because you can't say "run all the workflows" you have to do it both per-push, and per-workflow. The drop-down to select the branch to run is also a bit annoying in that it doesn't sort by recently pushed (If I remember right).

I'm not strictly opposed to using the branch name approach if I'm in the rough here, but I would prefer it be consistent between rustls org repos if we can swing it.

[djc]

Do you plan to do this in the other repos, e.g. rustls/rustls? I think it would be valuable to do this consistently, at least in the magic prefix/suffix to get it to happen for a branch push intentionally. E.g. rustls-platform-verifier is using *_dev, can we standardize on that?

Yes, I can probably do this for the other repos -- agreed on the value of consistency. Do you prefer using *_dev? I like that ci/ is a little more explicit about the goal (and I sort of generally prefer / or - over _, which might be silly), but don't feel too strongly (and given that I just open PRs directly my workflow wouldn't be impacted).

[cpu]

Do you prefer using *_dev? I like that ci/ is a little more explicit about the goal

No strong preference here. ci/ seems OK if you like that one. I don't think anyone will mind a change from *_dev on the rustls-platform-verifier repo, and I don't think we restrict CI by branch name in any other org repos presently.