Adds a column to help the operator see if they configured HRA.Spec.ScheduledOverrides correctly, in a form of "next override schedule recognized by the controller":
```
$ k get horizontalrunnerautoscaler
NAME MIN MAX DESIRED SCHEDULE
actions-runner-aos-autoscaler 0 5 0
org 0 5 0 min=0 time=2021-05-21 15:00:00 +0000 UTC
```
Ref https://github.com/actions-runner-controller/actions-runner-controller/issues/484
This adds the initial version of ScheduledOverrides to HorizontalRunnerAutoscaler.
`MinReplicas` overriding should just work.
When there are two or more ScheduledOverrides, the earliest one that matched is activated. Each ScheduledOverride can be recurring or one-time. If you have two or more ScheduledOverrides, only one of them should be one-time. And the one-time override should be the earliest item in the list to make sense.
Tests will be added in another commit. Logging improvements and additional observability in HRA.Status will also be added in yet another commits.
Ref #484
This allows you to trigger autoscaling depending on check_run names(i.e. actions job names). If you are willing to differentiate scale amount only for a specific job, or want to scale only on a specific job, try this.
* feat: HorizontalRunnerAutoscaler Webhook server
This introduces a Webhook server that responds GitHub `check_run`, `pull_request`, and `push` events by scaling up matched HorizontalRunnerAutoscaler by 1 replica. This allows you to immediately add "resource slack" for future GitHub Actions job runs, without waiting next sync period to add insufficient runners.
This feature is highly inspired by https://github.com/philips-labs/terraform-aws-github-runner. terraform-aws-github-runner can manage one set of runners per deployment, where actions-runner-controller with this feature can manage as many sets of runners as you declare with HorizontalRunnerAutoscaler and RunnerDeployment pairs.
On each GitHub event received, the webhook server queries repository-wide and organizational runners from the cluster and searches for the single target to scale up. The webhook server tries to match HorizontalRunnerAutoscaler.Spec.ScaleUpTriggers[].GitHubEvent.[CheckRun|Push|PullRequest] against the event and if it finds only one HRA, it is the scale target. If none or two or more targets are found for repository-wide runners, it does the same on organizational runners.
Changes:
* Fix integration test
* Update manifests
* chart: Add support for github webhook server
* dockerfile: Include github-webhook-server binary
* Do not import unversioned go-github
* Update README
Currently, after refreshing the token, the controller re-creates the runner with the new token. This results in jobs being interrupted. This PR makes sure the pod is not restarted if it is busy.
Closes#74
