preview.yml

name: Upload Preview

on:
  workflow_run:
    workflows: ["Build Preview"]
    types:
      - completed

jobs:
  upload:
    name: 'upload PR preview'
    runs-on: ubuntu-latest
    if: >
      ${{
        github.event.workflow_run.event == 'pull_request' &&
        github.event.workflow_run.conclusion == 'success' &&
        github.repository == 'tc39/ecma262'
      }}

    steps:
      - uses: actions/checkout@v2
      - uses: ljharb/actions/node/install@56f291b2a0d9e3bce72634356ae949b1e054b9f8
        name: 'nvm install lts/* && npm ci'
        with:
          node-version: lts/*
          use-npm-ci: true
      - name: 'Download artifact'
        uses: actions/github-script@v3.1.0
        with:
          script: |
            const { owner, repo } = context.repo;
            const artifacts = await github.actions.listWorkflowRunArtifacts({
               owner,
               repo,
               run_id: ${{ github.event.workflow_run.id }},
            });
            const { id: artifact_id } = artifacts.data.artifacts.find((artifact) => artifact.name == 'out');
            const download = await github.actions.downloadArtifact({
               owner,
               repo,
               artifact_id,
               archive_format: 'zip',
            });
            const fs = require('fs');
            fs.writeFileSync('${{ github.workspace }}/out.zip', Buffer.from(download.data));
      - run: unzip -o out.zip -d out
      - name: 'debug info'
        uses: actions/github-script@v3.1.0
        with:
          script: |
            console.log(${{ toJson(github.event) }});
      - run: head -n1 out/pr.txt | grep -e '^[1-9][0-9]*$'
        name: 'validate PR number from archive'
      - run: echo "PULL_REQUEST=$(head -n1 out/pr.txt)" >> $GITHUB_ENV
      - run: rm out/pr.txt && echo $PULL_REQUEST
      - run: node scripts/publish-preview
        env:
          CI_PREVIEW_TOKEN: ${{ secrets.CI_PREVIEW_TOKEN }}
          GITHUB_HEAD_SHA: ${{ github.event.workflow_run.head_commit.id }}