Hooks

Going over the entire list of issues, there are requests that would need extra logic from subtle changes to pretty wild out there ideas or edge cases that would be hard to implement and maintain.

With hooks the burden for customization is with the user. That way the focus here can be more on making sure the mechanics around basic GitLab interactions are solid.

Add hooks for customizing pipeline message (!469 - merged) introduced a mechanism that might work.

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Here's a brain dump of what might be needed and what it might cover, locations and ordering might not be accurate, names are just ideas, and I'll keep updating as I find more issues, feel free to add stuff.

1. startup
   • entire app cycle
   • setup, massage config
     • Support for webhook (#389) e.g. single targeted run triggered from webhook
2. run
   • every run iteration
   • more dynamic config based on some state/time of run etc
3. post-collect
   • almost the same as above, but massage collected MRs
     • Feature request: Add MR priority support (#153)
     • Feature request: let marge bot leave a comment ... (#346)
4. pre-push
   • before push unless API rebase
     • Execute repo-controlled script during the "reba... (#391)
     • Handle fixup commits (#16)
     • Rewrite commit hashes in commit messages (#17)
5. embargo
   • when skipping during embargoes
     • Leave a message on the MR when not merging due ... (#1)
6. pre-merge
   • custom checks for mergeable MRs
     • Support for extra pre-merge checks (#296)
     • Allow forcing "Only allow merge requests to be ... (#273)
7. post-merge (+ batch)
   • custom labeling etc
     • Allow Marge to re-assign to last assignee after... (#290)
     • feature request: allow disabling merges for cer... (#334)
     • Teach marge-bot how to backport merge requests (#278)
8. shutdown
   • cleanup
     • make marge-bot to reuse the repo for HTTPS (#408 - closed) (might be needed per loop though)
9. ...