github: bot for automatic PR maintenance

[metux]

Describe the idea

Write / find a bot (or something running within a pipeline) that's taking care of usual PR maintenance tasks, eg.:

• assign reviewers (possibly based on certain policies, eg. by touched file set)
• assign milestone based on target branch
• check whether commits in maintenance branch also already made it to master
• inform on merge conflicts (eg. send mails or post a comment)

It should be done because

doing this manually takes a lot of time. and for certain tasks (eg. reviewer assignment) not everybody has the proper permissions.

What are the alternatives?

No response

Additional context

No response

Extra fields

• I have checked the existing New Ideas, RFCs Of The Core Team, Ideas Soon To Be Addressed and Someday Ideas
• I have read the Contributing Guidelines
• I'd like to work on this idea

[metux]

@callmetango do you have an idea on that ?

[callmetango]

First of all: I reeaaally like the idea! Regarding this:

assign reviewers (possibly based on certain policies, eg. by touched file set)

we could use the Github code owners - GitHub Docs feature. This is a simple text file containing said policies stating which reviewers to assign by default depending on the file extension or file path. This is already built into Github and needs no permissions nor manual assignment. Simple rules, good results.

[callmetango]

• assign milestone based on target branch

This Pull Request Milestone · Actions · GitHub Marketplace might do the trick. Haven't tested it, but the description seems to apply to your, er, wish.

[metux]

Good start, but this one requires the milestone title to be part of the target branch, which is absolutely not fitting for our case.
We would eg. also have to rename master branch to something like "25.1" - and rename it with each new release again.

What we'd need here is an explicit mapping. And even then the mapping needs to be updated with each release.

[callmetango]

inform on merge conflicts (eg. send mails or post a comment)

This Notify Merge Conflict · Actions · GitHub Marketplace might do the trick in this case. Again untested, but could/should work.

[metux]

X11Libre/xserver#703

[callmetango]

check whether commits in maintenance branch also already made it to master

This might be a bit more tricky and I am not sure whether there is some solution out of the box. Will have to think about this and research more.