element-web/.github/workflows/netlify.yaml

# Triggers after the layered build has finished, taking the artifact
# and uploading it to netlify
name: Upload Preview Build to Netlify
on:
    workflow_run:
        workflows: ["Element Web - Build and Test"]
        types:
            - completed
jobs:
    build:
        runs-on: ubuntu-latest
        if: >
            ${{ github.event.workflow_run.conclusion == 'success' && github.event.workflow_run.event == 'pull_request' }}
        steps:
            - name: "🔍 Read PR number"
              id: readctx
              # we need to find the PR number that corresponds to the branch, which we do by
              # searching the GH API
              # The workflow_run event includes a list of pull requests, but it doesn't get populated for
              # forked PRs: https://docs.github.com/en/rest/reference/checks#create-a-check-run
              run: |
                head_branch='${{github.event.workflow_run.head_repository.owner.login}}:${{github.event.workflow_run.head_branch}}'
                echo "head branch: $head_branch"
                pulls_uri="https://api.github.com/repos/${{ github.repository }}/pulls?head=$(jq -Rr '@uri' <<<$head_branch)"
                pr_number=$(curl -s -H 'Authorization: Bearer ${{ secrets.GITHUB_TOKEN }}' "$pulls_uri" |
                     jq -r '.[] | .number')
                echo "PR number: $pr_number"
                echo "::set-output name=prnumber::$pr_number"
            # There's a 'download artifact' action but it hasn't been updated for the
            # workflow_run action (https://github.com/actions/download-artifact/issues/60)
            # so instead we get this mess:
            - name: 'Download artifact'
              uses: actions/github-script@v3.1.0
              with:
                script: |
                  var artifacts = await github.actions.listWorkflowRunArtifacts({
                     owner: context.repo.owner,
                     repo: context.repo.repo,
                     run_id: ${{github.event.workflow_run.id }},
                  });
                  var matchArtifact = artifacts.data.artifacts.filter((artifact) => {
                    return artifact.name == "previewbuild"
                  })[0];
                  var download = await github.actions.downloadArtifact({
                     owner: context.repo.owner,
                     repo: context.repo.repo,
                     artifact_id: matchArtifact.id,
                     archive_format: 'zip',
                  });
                  var fs = require('fs');
                  fs.writeFileSync('${{github.workspace}}/previewbuild.zip', Buffer.from(download.data));
            - name: Extract Artifacts
              run: unzip -d webapp previewbuild.zip && rm previewbuild.zip
            - name: Deploy to Netlify
              id: netlify
              uses: nwtgck/actions-netlify@v1.2
              with:
                  publish-dir: webapp
                  deploy-message: "Deploy from GitHub Actions"
                  # These don't work because we're in workflow_run
                  enable-pull-request-comment: false
                  enable-commit-comment: false
                  alias: pr${{ steps.readctx.outputs.prnumber }}
              env:
                  NETLIFY_AUTH_TOKEN: ${{ secrets.NETLIFY_AUTH_TOKEN }}
                  NETLIFY_SITE_ID: ${{ secrets.NETLIFY_SITE_ID }}
              timeout-minutes: 1
            - name: Edit PR Description
              uses: Beakyn/gha-comment-pull-request@2167a7aee24f9e61ce76a23039f322e49a990409
              env:
                  GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
              with:
                  pull-request-number: ${{ steps.readctx.outputs.prnumber }}
                  description-message: |
                      Preview: ${{ steps.netlify.outputs.deploy-url }}
                      ⚠️ Do you trust the author of this PR? Maybe this build will steal your keys or give you malware. Exercise caution. Use test accounts.