.github/workflows/build-push.yml

name: build preview

on: 
  pull_request:
    branches:
      - "*"

env:
    REPO_OWNER: "nginx"
    REPO_NAME: "documentation"
    FRONT_DOOR_USERNAME: ${{ secrets.FRONT_DOOR_USERNAME }}
    FRONT_DOOR_PASSWORD: ${{ secrets.FRONT_DOOR_PASSWORD }}
    GITHUB_PR_NUMBER: ${{ github.event.pull_request.number }}
    MAIN_REPORT_ARTIFACT_NAME: "lighthouse-reports-main"  

jobs:
    deploy-example-site:
      uses: nginxinc/docs-actions/.github/workflows/docs-build-push.yml@04ed2db338ee08cc560a327f412684d0c8260de2 # v1.0.11
      with:
        production_url_path: "/nginx-hugo-theme"
        preview_url_path: "/previews/nginx-hugo-theme"
        docs_source_path: "public"
        docs_build_path: "./exampleSite"
        doc_type: "hugo"
        environment: "preview"
        force_hugo_theme_version: ""
        auto_deploy_branch: "main"
        auto_deploy_env: "prod"
      secrets:
        AZURE_CREDENTIALS: ${{secrets.AZURE_CREDENTIALS_DOCS}}
        AZURE_KEY_VAULT: ${{secrets.AZURE_KEY_VAULT_DOCS}}
    lighthouseci:
      if: github.event.pull_request
      needs: deploy-example-site
      runs-on: ubuntu-22.04
      steps:
        - uses: actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8 # v5.0.0
          with:
            ref: ${{ github.event.workflow_run.head_branch }}
        - uses: actions/setup-node@a0853c24544627f65ddf259abe73b1d18a591444 # v5.0.0
          with:
            node-version: 22
        - name: Installing packages
          run: cd performance && npm ci
        - name: Generating lighthouse reports for PR...
          env: 
            REPORT_NAME: "pr"
          run: | 
              node performance/lighthouse-script.js
        - name: Retrieve the latest artifact ID for lighthouse report main
          uses: actions/github-script@ed597411d8f924073f98dfc5c65a23a2325f34cd # v8.0.0
          id: fetch-artifact-id
          with: 
            script: |
              const { owner, repo } = context.issue;
              const response = await github.rest.actions.listArtifactsForRepo({
                owner,
                repo,
              });

              const artifactName = process.env.MAIN_REPORT_ARTIFACT_NAME;
              const filteredArtifacts = response.data.artifacts.filter(a => a.name === artifactName);

              if(filteredArtifacts.length === 0) {
                return core.setFailed(`Error: Not able to find artifact with name ${artifactName}`);
              }

              const latestArtifact = filteredArtifacts.sort((a, b) => new Date(b.created_at) - new Date(a.created_at))[0];
              console.log(`Success! Found the latest artifact with name ${artifactName}, with artifact id ${latestArtifact.id} | workflow id ${latestArtifact.workflow_run.id}`);

              const download = await github.rest.actions.downloadArtifact({
                owner: owner,
                repo: repo,
                artifact_id: latestArtifact.id,
                archive_format: 'zip',
              });

              const fs = require('fs');
              fs.writeFileSync('./artifact-lighthouse-report-main.zip', Buffer.from(download.data));
              
            result-encoding: string
        - name: Unzip the artifact
          run: |
            unzip ./artifact-lighthouse-report-main.zip
            ls -al
        - name: Move the main report artifact to same directory as pr report
          run: |
            mv main-report.json ./lighthouse-reports
        - name: Compare the artifacts for negative differences in performance
          continue-on-error: true
          run: |
              FIELDS=("performance" "accessibility") 
              TOLERANCE=0.05
              FLOOR_VALUE=0.90
              for FIELD in "${FIELDS[@]}"; do
                  PR_VALUE=$(cat lighthouse-reports/pr-report.json | jq -r ".categories.$FIELD.score")
                  MAIN_VALUE=$(cat lighthouse-reports/main-report.json | jq -r ".categories.$FIELD.score")
                  echo "$FIELD: PR - $PR_VALUE | Main - $MAIN_VALUE"

                  if (( $(echo "$PR_VALUE < $FLOOR_VALUE" | bc -l) )); then
                      echo "Error: $FIELD score in PR ($PR_VALUE) is less than accepted value ($FLOOR_VALUE)"
                      exit 1
                  fi

                  if [ $FIELD = "performance" ]; then  
                    LOWER_BOUND=$(echo "$MAIN_VALUE - $TOLERANCE" | bc)
                    UPPER_BOUND=$(echo "$MAIN_VALUE + $TOLERANCE" | bc)
                    if (( $(echo "$PR_VALUE < $LOWER_BOUND" | bc -l) || $(echo "$PR_VALUE > $UPPER_BOUND" | bc -l) )); then
                        echo "Error: $FIELD score in PR ($PR_VALUE) is less than in MAIN ($MAIN_VALUE)"
                        exit 1
                    fi
                  else
                    if (( $(echo "$PR_VALUE < $MAIN_VALUE" | bc -l) )); then
                      echo "Error: $FIELD score in PR ($PR_VALUE) is less than in MAIN ($MAIN_VALUE)"
                      exit 1
                    fi
                  fi
              done
        - uses: actions/upload-artifact@6f51ac03b9356f520e9adb1b1b7802705f340c2b # v4.5.0
          if: ${{ !cancelled() }}
          with:
              name: lighthouse-reports-pr
              path: lighthouse-reports/pr-report.json
              retention-days: 3