The [ListRunnerGroup API](https://docs.github.com/en/rest/reference/actions#list-self-hosted-runner-groups-for-an-organization) now add a new query parameter `visible_to_repository`.
We were doing `N+1` lookup when trying to find which runner group can be used for job from a certain repository.
- List all runner groups
- Loop through all groups to check repository access for each of them via [API](https://docs.github.com/en/rest/reference/actions#list-repository-access-to-a-self-hosted-runner-group-in-an-organization)
The new query parameter `visible_to_repository` should allow us to get the runner groups with access in one call.
Limitation:
- The new query parameter is only supported in GitHub.com, which means anyone who uses ARC in GitHub Enterprise Server won't get this.
- I am working on a PR to update `go-github` library to support the new parameter, but it will take a few weeks for a newer `go-github` to be released, so in the meantime, I am duplicating the implementation in ARC as well to support the new query parameter.
This will work on GHES but GitHub Enterprise Cloud due to excessive GitHub API calls required.
More work is needed, like adding a cache layer to the GitHub client, to make it usable on GitHub Enterprise Cloud.
Fixes additional cases from https://github.com/actions-runner-controller/actions-runner-controller/pull/1012
If GitHub auth is provided in the webhooks controller then runner groups with custom visibility are supported. Otherwise, all runner groups will be assumed to be visible to all repositories
`getScaleUpTargetWithFunction()` will check if there is an HRA available with the following flow:
1. Search for **repository** HRAs - if so it ends here
2. Get available HRAs in k8s
3. Compute visible runner groups
a. If GitHub auth is provided - get all the runner groups that are visible to the repository of the incoming webhook using GitHub API calls.
b. If GitHub auth is not provided - assume all runner groups are visible to all repositories
4. Search for **default organization** runners (a.k.a runners from organization's visible default runner group) with matching labels
5. Search for **default enterprise** runners (a.k.a runners from enterprise's visible default runner group) with matching labels
6. Search for **custom organization runner groups** with matching labels
7. Search for **custom enterprise runner groups** with matching labels
Co-authored-by: Yusuke Kuoka <ykuoka@gmail.com>
Yusuke Kuoka
Tingluo Huang
Felipe Galindo Sanchez