retry-transient-failures.yml

name: Retry Transient Workflow Failures

on:
  workflow_run:
    workflows:
      - Project Board Automation
      - Changelog Automation
      - Pull Request Label Sync
      - Generate Reports and Deploy to GitHub Pages
      - Rigorous Pull Request Review
      - Run PHPUnit Tests
      - Maintain Wiki
      - Maintain Wiki Publication
      - Update Wiki Preview
      - Update Wiki
    types:
      - completed

permissions:
  actions: write
  contents: read

concurrency:
  group: retry-transient-run-${{ github.event.workflow_run.id }}
  cancel-in-progress: false

jobs:
  retry:
    if: ${{ github.event.workflow_run.conclusion == 'failure' }}
    name: Retry Failed Jobs When GitHub Infrastructure Looks Transient
    runs-on: ubuntu-latest

    steps:
      - id: retry
        uses: actions/github-script@v9
        with:
          github-token: ${{ secrets.GITHUB_TOKEN }}
          script: |
            const transientPatterns = [
              /RPC failed; HTTP 5\d\d/i,
              /expected flush after ref listing/i,
              /expected 'packfile'/i,
              /remote:\s+Internal Server Error/i,
              /requested URL returned error:\s*5\d\d/i,
              /fatal:\s+unable to access 'https:\/\/github\.com\/.*': The requested URL returned error:\s*5\d\d/i,
            ];

            const [owner, repo] = process.env.GITHUB_REPOSITORY.split('/');
            const runId = Number.parseInt(`${{ github.event.workflow_run.id }}`, 10);
            const runAttempt = Number.parseInt(`${{ github.event.workflow_run.run_attempt }}`, 10);
            const workflowName = `${{ github.event.workflow_run.name }}`;
            const maxRunAttempts = 2;

            const buildSummary = ({ status, failedJobs = [], matchedJobs = [] }) => {
              const lines = [
                '## Transient Failure Retry Summary',
                '',
                `- Workflow: \`${workflowName}\``,
                `- Run ID: \`${runId}\``,
                `- Run attempt: \`${runAttempt}\``,
                `- Retry status: \`${status}\``,
              ];

              if (failedJobs.length > 0) {
                lines.push(`- Failed jobs inspected: ${failedJobs.map((job) => `\`${job}\``).join(', ')}`);
              }

              if (matchedJobs.length > 0) {
                lines.push(`- Jobs with transient GitHub failure signatures: ${matchedJobs.map((job) => `\`${job}\``).join(', ')}`);
              }

              if (status === 'rerun-requested') {
                lines.push('- Action: Requested a rerun of failed jobs because every failed job matched transient GitHub-side error signatures.');
              }

              if (status === 'skipped-run-attempt-limit') {
                lines.push('- Action: Skipped rerun because the run already reached the configured retry limit.');
              }

              if (status === 'skipped-no-failed-jobs') {
                lines.push('- Action: Skipped rerun because the workflow reported failure without failed jobs to inspect.');
              }

              if (status === 'skipped-no-transient-match') {
                lines.push('- Action: Skipped rerun because at least one failed job did not match the transient GitHub-side signatures.');
              }

              return lines.join('\n');
            };

            if (runAttempt >= maxRunAttempts) {
              const summary = buildSummary({ status: 'skipped-run-attempt-limit' });
              core.setOutput('status', 'skipped-run-attempt-limit');
              core.setOutput('summary', summary);

              return;
            }

            const jobsResponse = await github.rest.actions.listJobsForWorkflowRun({
              owner,
              repo,
              run_id: runId,
              per_page: 100,
            });

            const failedJobs = jobsResponse.data.jobs.filter((job) => job.conclusion === 'failure');

            if (failedJobs.length === 0) {
              const summary = buildSummary({ status: 'skipped-no-failed-jobs' });
              core.setOutput('status', 'skipped-no-failed-jobs');
              core.setOutput('summary', summary);

              return;
            }

            const matchedJobs = [];

            for (const job of failedJobs) {
              const logsResponse = await fetch(`https://api.github.com/repos/${owner}/${repo}/actions/jobs/${job.id}/logs`, {
                headers: {
                  Accept: 'application/vnd.github+json',
                  Authorization: `Bearer ${process.env.GITHUB_TOKEN}`,
                  'X-GitHub-Api-Version': '2022-11-28',
                },
                redirect: 'follow',
              });

              if (!logsResponse.ok) {
                throw new Error(`Failed to download logs for job ${job.name}: ${logsResponse.status} ${logsResponse.statusText}`);
              }

              const logText = await logsResponse.text();
              const hasTransientMatch = transientPatterns.some((pattern) => pattern.test(logText));

              if (!hasTransientMatch) {
                const summary = buildSummary({
                  status: 'skipped-no-transient-match',
                  failedJobs: failedJobs.map((failedJob) => failedJob.name),
                  matchedJobs,
                });

                core.setOutput('status', 'skipped-no-transient-match');
                core.setOutput('summary', summary);

                return;
              }

              matchedJobs.push(job.name);
            }

            await github.request('POST /repos/{owner}/{repo}/actions/runs/{run_id}/rerun-failed-jobs', {
              owner,
              repo,
              run_id: runId,
            });

            const summary = buildSummary({
              status: 'rerun-requested',
              failedJobs: failedJobs.map((job) => job.name),
              matchedJobs,
            });

            core.setOutput('status', 'rerun-requested');
            core.setOutput('summary', summary);

      - name: Write step summary
        env:
          RETRY_SUMMARY: ${{ steps.retry.outputs.summary }}
        run: printf '%s\n' "$RETRY_SUMMARY" >> "$GITHUB_STEP_SUMMARY"