backend-pr-labeler.yml

name: Backend PR Labeler
on:
  pull_request:
    types: [opened, reopened, review_requested, review_request_removed, ready_for_review, converted_to_draft, labeled, unlabeled]
  pull_request_review:
    types: [submitted]
  workflow_run:
    workflows: 
      - "Code Checks"
    types: [completed]
jobs:
  check-pr-status:
    runs-on: ubuntu-latest
    env:
      GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
    outputs:
      pr_number: ${{ steps.get_pr_data.outputs.pr_number }}
      pr_draft: ${{ steps.get_pr_data.outputs.pr_draft }}
      pr_labels: ${{ steps.get_pr_data.outputs.pr_labels }}
      pr_requested_teams: ${{ steps.get_pr_data.outputs.pr_requested_teams }}
      test_status: ${{ steps.get_code_checks_conclusion.outputs.test_status }}
      exempt: ${{ steps.check_exemption.outputs.exempt }}
      failures_detected: ${{ steps.audit_pr_labels.outputs.failures_detected }}
    steps:
      - name: Get pull_request data
        id: get_pr_data
        run: |
          if ${{ github.event_name == 'pull_request'}}; then
            echo "pr_number=${{ github.event.pull_request.number }}" >> $GITHUB_OUTPUT
            echo "pr_draft=${{ github.event.pull_request.draft }}" >> $GITHUB_OUTPUT
            echo "pr_labels=$(echo '${{ toJSON(github.event.pull_request.labels.*.name) }}' | jq -c '.')" >> $GITHUB_OUTPUT
            echo "pr_requested_teams=$(echo '${{ toJSON(github.event.pull_request.requested_teams.*.name) }}' | jq -c '.')" >> $GITHUB_OUTPUT
          elif ${{ github.event_name == 'pull_request_review' }}; then
            echo "pr_number=${{ github.event.pull_request_review.pull_request.number }}" >> $GITHUB_OUTPUT
            echo "pr_draft=${{ github.event.pull_request_review.pull_request.draft }}" >> $GITHUB_OUTPUT
            echo "pr_labels=$(echo '${{ toJSON(github.event.pull_request_review.pull_request.labels.*.name) }}' | jq -c '.')" >> $GITHUB_OUTPUT
            echo "pr_requested_teams=$(echo '${{ toJSON(github.event.pull_request_review.pull_request.requested_teams.*.name) }}' | jq -c '.')" >> $GITHUB_OUTPUT
          elif ${{ github.event_name == 'workflow_run' }}; then
            if ${{ github.event.workflow_run.event == 'push' }}; then
              echo "Workflow was triggered by push to ${{ github.event.workflow_run.head_branch }}. Labeling not required."
              exit 0
            elif ${{ toJSON(github.event.workflow_run.pull_requests) != '[]' }}; then
              PR_NUMBER="${{ github.event.workflow_run.pull_requests[0].number }}"
              echo "pr_number=${PR_NUMBER}" >> $GITHUB_OUTPUT
            
              # Fetch PR details from GitHub API
              PR_INFO=$(gh api /repos/${{ github.repository }}/pulls/${PR_NUMBER} --jq '{
                draft: .draft,
                labels: [.labels[].name],
                requested_teams: [.requested_teams[].slug]
              }')
              
              # Extract and store individual fields
              echo "pr_draft=$(echo "$PR_INFO" | jq -r '.draft')" >> $GITHUB_OUTPUT
              echo "pr_labels=$(echo "$PR_INFO" | jq -c '.labels')" >> $GITHUB_OUTPUT
              echo "pr_requested_teams=$(echo "$PR_INFO" | jq -c '.requested_teams')" >> $GITHUB_OUTPUT
            else
              echo "Workflow run has no associated pull requests. Labeling not performed."
              exit 0
            fi
          else
            echo "event_name: ${{ github.event_name }}"
            echo "Pull Request not successfully retrieved."
            exit 1
          fi

      - name: Echo PR data
        run: |
          echo "pr_number: ${{ steps.get_pr_data.outputs.pr_number }}"
          echo "pr_draft: ${{ steps.get_pr_data.outputs.pr_draft }}"
          echo "pr_labels: ${{ steps.get_pr_data.outputs.pr_labels }}"
          echo "pr_labels: ${{ fromJson(steps.get_pr_data.outputs.pr_labels)[0] }}"
          echo "pr_requested_teams: ${{ steps.get_pr_data.outputs.pr_requested_teams }}"
          echo "pr_requested_teams: ${{ fromJSON(steps.get_pr_data.outputs.pr_requested_teams)[0] }}"

      - name: Get Code Checks result
        if: github.event_name == 'workflow_run'
        run: |
          echo "test_status=${{ github.event.workflow_run.conclusion }}" >> $GITHUB_OUTPUT
          echo "test_status: ${{ github.event.workflow_run.conclusion }}"

      - name: Check for exemption
        id: check_exemption
        run: |
          if ${{ contains(fromJSON(steps.get_pr_data.outputs.pr_requested_teams), 'backend-review-group') }}; then
            echo "exempt=false" >> $GITHUB_OUTPUT
            echo "PR requires backend approval."
          else
            echo "exempt=true" >> $GITHUB_OUTPUT
            echo "PR is exempt from backend approval."
          fi

      - name: Check for failure labels
        id: audit_pr_labels
        env:
          labels: ${{ steps.get_pr_data.outputs.pr_labels }}
        run: |
          if \
            ${{ contains(env.labels, 'code-health-failure') }} ||\
            ${{ contains(env.labels, 'codeowners-addition-failure') }} ||\
            ${{ contains(env.labels, 'codeowners-delete-failure') }} ||\
            ${{ contains(env.labels, 'lint-failure') }} ||\
            ${{ contains(env.labels, 'test-failure') }} ; then
            echo "failures_detected=true" >> $GITHUB_OUTPUT
            echo "Failure labels detected."
          else
            echo "failures_detected=false" >> $GITHUB_OUTPUT
            echo "No failure labels detected."
          fi