.github/workflows/revert-trigger.yml

# Copyright 2013 The Flutter Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.

# Unprivileged half of the revert automation.
#
# This workflow runs on `pull_request` with a read-only token and no access to
# secrets. When the `revert` label is applied, it records the pull request
# number in a `revert-metadata` artifact. The privileged `revert.yml` workflow
# consumes that artifact via `workflow_run`, validates the request, and either
# performs the revert or comments on the pull request explaining why it can't.

name: Revert Trigger

on:
  pull_request:
    types: [labeled]

permissions:
  contents: read

jobs:
  record:
    name: Record revert request
    runs-on: ubuntu-latest
    # Evaluated before a runner is allocated, so other labels cost nothing.
    if: github.repository == 'flutter/flutter' && github.event.label.name == 'revert'
    steps:
      - name: Record PR number
        env:
          PR_NUMBER: ${{ github.event.pull_request.number }}
        run: |
          mkdir -p revert-metadata
          jq -n --arg pr "$PR_NUMBER" '{pr_number: $pr}' > revert-metadata/metadata.json

      - name: Upload revert metadata
        uses: actions/upload-artifact@cf430e030ddbb5b0abf93d22962f4752f3646cd9 # v7.0.2
        with:
          name: revert-metadata
          path: revert-metadata/
          retention-days: 1
          if-no-files-found: error