name: Cancel Previous Runs
on: [push, pull_request]

defaults:
  run:
    shell: bash

jobs:
  cancel:
    name: Cancel Previous Runs
    runs-on: ubuntu-latest
    timeout-minutes: 3

    # Don't run this job for zulip/zulip pushes since we
    # want to run those jobs.
    if: ${{ github.event_name != 'push' || github.event.repository.full_name != 'zulip/zulip' }}

    steps:
      # We get workflow IDs from GitHub API so we don't have to maintain
      # a hard-coded list of IDs which need to be updated when a workflow
      # is added or removed. And, workflow IDs are different for other forks
      # so this is required.
      - name: Get workflow IDs.
        id: workflow_ids
        env:
          # This is in <owner>/<repo> format e.g. zulip/zulip
          REPOSITORY: ${{ github.repository }}
        run: |
          workflow_api_url=https://api.github.com/repos/$REPOSITORY/actions/workflows
          curl $workflow_api_url -o workflows.json

          script="const {workflows} = require('./workflows'); \
                  const ids = workflows.map(workflow => workflow.id); \
                  console.log(ids.join(','));"
          ids=$(node -e "$script")
          echo "::set-output name=ids::$ids"

      - uses: styfle/cancel-workflow-action@0.4.1
        with:
          workflow_id: ${{ steps.workflow_ids.outputs.ids }}
          access_token: ${{ github.token }}