Derive accepted PR labels from the repository

.github/workflows/pr-label.yml

@@ -4,15 +4,18 @@ on:
  pull_request:
  types: [opened, reopened, synchronize, labeled, unlabeled]
 
+permissions:
+ issues: read
+ pull-requests: read
+
 jobs:
  labels:
  runs-on: ubuntu-latest
  steps:
- - name: Require a lerna-changelog label
+ - name: Require a repository label
  uses: actions/github-script@v9
  with:
  script: |
- const required = ["breaking", "enhancement", "bug", "documentation", "internal"];
  const pullRequest = context.payload.pull_request;
  // Dependabot and friends label their own PRs (dependencies,
  // javascript, github_actions) and cannot be asked to pick a
@@ -25,10 +28,17 @@ jobs:
  );
  return;
  }
- const labels = pullRequest.labels.map((label) => label.name);
- const matched = labels.filter((label) => required.includes(label));
+ const repositoryLabels = await github.paginate(
+ github.rest.issues.listLabelsForRepo,
+ { ...context.repo, per_page: 100 },
+ (response) => response.data.map((label) => label.name),
+ );
+ const validLabels = new Set(repositoryLabels);
+ const matched = pullRequest.labels
+ .map((label) => label.name)
+ .filter((label) => validLabels.has(label));
  if (matched.length === 0) {
  core.setFailed(
- `This PR needs one of the following labels for the changelog: ${required.join(", ")}.`,
+ `This PR needs at least one repository label. Available labels: ${repositoryLabels.sort().join(", ")}.`,
  );
  }