status-reconciler

status-reconciler ensures that changes to blocking presubmits in Prow configuration while PRs are in flight do not cause those PRs to get stuck.

When the set of blocking presubmits changes for a repository, one of three cases occurs:

• a new blocking presubmit exists and should be triggered for every trusted pull request in flight
• an existing blocking presubmit is removed and should have its' status retired
• an existing blocking presubmit is renamed and should have its' status migrated

The status-reconciler watches the job configuration for Prow and ensures that the above actions are taken as necessary.

To exclude repos from being reconciled, passing flag --denylist, this can be done repeatedly. This is useful when moving a repo from prow instance A to prow instance B, while unwinding jobs from prow instance A, the jobs are not expected to be blindly lablled succeed by prow instance A.

Note that status-reconciler is edge driven (not level driven) so it can’t be used retrospectively.