preview-shop-pr.yml

# Dynamic mirrord Preview Environment: detects changed services, builds images,
# and starts a preview for each. Posts a single aggregated PR comment + Slack message.
# Uses metalbear-co/mirrord-preview GitHub Action.
# Requires: GCP_WIF_PROVIDER + GCP_SERVICE_ACCOUNT + SLACK_WEBHOOK_URL secrets,
# mirrord operator with Enterprise license.
name: Preview Environment - Shop (Dynamic)

on:
  pull_request:
    types: [opened, reopened, closed]

concurrency:
  group: preview-shop-${{ github.event.pull_request.number }}
  cancel-in-progress: true

env:
  PREVIEW_KEY: "${{ github.head_ref }}"

jobs:
  # ─── Job 1: Detect which services changed ───
  detect-changes:
    name: Detect changed services
    if: github.event.action != 'closed'
    runs-on: ubuntu-latest
    outputs:
      matrix: ${{ steps.build-matrix.outputs.matrix }}
      has_changes: ${{ steps.build-matrix.outputs.has_changes }}
      services_list: ${{ steps.build-matrix.outputs.services_list }}
    steps:
      - name: Checkout
        uses: actions/checkout@v4
        with:
          fetch-depth: 0

      - name: Detect changed services via git diff
        id: build-matrix
        run: |
          CHANGED_FILES=$(git diff --name-only origin/${{ github.base_ref }}...HEAD)
          CHANGES='[]'
          for path in $(jq -r '.services[].path' .github/preview-services.json); do
            name=$(jq -r --arg p "$path" '.services[] | select(.path == $p) | .name' .github/preview-services.json)
            if echo "$CHANGED_FILES" | grep -q "^${path}/"; then
              CHANGES=$(echo "$CHANGES" | jq -c --arg n "$name" '. + [$n]')
            fi
          done
          MATRIX=$(jq -c --argjson changes "$CHANGES" \
            '{include: [.services[] | select(.name as $n | $changes | index($n))]}' \
            .github/preview-services.json)
          SERVICES_LIST=$(jq -r --argjson changes "$CHANGES" \
            '[.services[] | select(.name as $n | $changes | index($n)) | .name] | join(", ")' \
            .github/preview-services.json)
          COUNT=$(echo "$CHANGES" | jq 'length')
          echo "matrix=$MATRIX" >> "$GITHUB_OUTPUT"
          echo "services_list=$SERVICES_LIST" >> "$GITHUB_OUTPUT"
          if [ "$COUNT" -gt 0 ]; then
            echo "has_changes=true" >> "$GITHUB_OUTPUT"
          else
            echo "has_changes=false" >> "$GITHUB_OUTPUT"
          fi
          echo "Changed services ($COUNT): $SERVICES_LIST"

  # ─── Job 2: Build image + start preview for each changed service ───
  build-and-preview:
    name: Build & Preview (${{ matrix.name }})
    needs: detect-changes
    if: needs.detect-changes.outputs.has_changes == 'true'
    runs-on: ubuntu-latest
    timeout-minutes: 30
    strategy:
      matrix: ${{ fromJSON(needs.detect-changes.outputs.matrix) }}
      fail-fast: false
    permissions:
      contents: read
      packages: write
      id-token: write
    steps:
      - name: Checkout
        uses: actions/checkout@v4

      - name: Set up QEMU
        uses: docker/setup-qemu-action@v3

      - name: Set up Docker Buildx
        uses: docker/setup-buildx-action@v3

      - name: Login to GitHub Container Registry
        uses: docker/login-action@v3
        with:
          registry: ghcr.io
          username: ${{ github.repository_owner }}
          password: ${{ secrets.GITHUB_TOKEN }}

      - name: Build and push image
        uses: docker/build-push-action@v5
        with:
          context: ${{ matrix.path }}
          file: ${{ matrix.path }}/Dockerfile
          platforms: linux/amd64
          push: true
          tags: ghcr.io/metalbear-co/playground-${{ matrix.name }}:preview-${{ github.head_ref }}-${{ github.sha }}
          build-args: ${{ matrix.build_args }}
          cache-from: type=gha,scope=${{ matrix.name }}
          cache-to: type=gha,scope=${{ matrix.name }},mode=max

      - name: Authenticate to GCP via Workload Identity Federation
        uses: google-github-actions/auth@v2
        with:
          workload_identity_provider: ${{ secrets.GCP_WIF_PROVIDER }}
          service_account: ${{ secrets.GCP_SERVICE_ACCOUNT }}

      - name: Get GKE credentials
        uses: google-github-actions/get-gke-credentials@v2
        with:
          cluster_name: playground-cluster-1
          location: us-central1-c
          project_id: playground-383912

      - name: Start mirrord preview
        uses: metalbear-co/mirrord-preview@master
        with:
          action: start
          target: deployment/${{ matrix.deployment }}
          namespace: ${{ matrix.namespace }}
          image: ghcr.io/metalbear-co/playground-${{ matrix.name }}:preview-${{ github.head_ref }}-${{ github.sha }}
          mode: steal
          filter: 'baggage:\s*[^\n]*\bmirrord={{ key }}\b'
          ttl_mins: '120'
          key: ${{ env.PREVIEW_KEY }}
          extra_config: ${{ matrix.extra_config }}

      - name: Write result artifact
        if: success()
        run: |
          mkdir -p /tmp/preview-results
          echo '{"name":"${{ matrix.name }}"}' > /tmp/preview-results/${{ matrix.name }}.json

      - name: Upload result artifact
        if: success()
        uses: actions/upload-artifact@v4
        with:
          name: preview-result-${{ matrix.name }}
          path: /tmp/preview-results/${{ matrix.name }}.json
          retention-days: 1

  # ─── Job 3: Post aggregated PR comment + Slack notification ───
  notify:
    name: Post notifications
    needs: [detect-changes, build-and-preview]
    if: needs.detect-changes.outputs.has_changes == 'true' && !cancelled()
    runs-on: ubuntu-latest
    permissions:
      pull-requests: write
    steps:
      - name: Download all result artifacts
        uses: actions/download-artifact@v4
        with:
          pattern: preview-result-*
          path: /tmp/preview-results
          merge-multiple: true

      - name: Post PR comment with preview details
        uses: actions/github-script@v7
        with:
          script: |
            const fs = require('fs');
            const path = require('path');
            const key = `${{ env.PREVIEW_KEY }}`;
            const url = 'https://playground.metalbear.dev/shop';

            // Read all result files to get list of successfully previewed services
            const dir = '/tmp/preview-results';
            let services = [];
            try {
              const files = fs.readdirSync(dir).filter(f => f.endsWith('.json'));
              services = files.map(f => JSON.parse(fs.readFileSync(path.join(dir, f), 'utf8')));
            } catch (e) {
              console.log('No preview results found, some or all previews may have failed.');
            }

            const serviceList = services.length > 0
              ? services.map(s => `| \`${s.name}\` | \`deployment/${s.name}\` |`).join('\n')
              : '| _(no previews succeeded)_ | |';

            const body = [
              '## mirrord Preview Environment - Metal Mart',
              '',
              'Preview environments are running for this PR.',
              '',
              '| Service | Target |',
              '|---|---|',
              serviceList,
              '',
              '| | |',
              '|---|---|',
              `| **Preview URL** | [${url}](${url}) |`,
              `| **Header** | \`baggage: mirrord=${key}\` |`,
              '',
              'To send traffic to this preview:',
              `- Use the [mirrord Browser Extension](https://metalbear.com/mirrord/docs/using-mirrord/browser-extension) and set the header for this URL, or`,
              `- \`curl -H "baggage: mirrord=${key}" ${url}\``,
              '',
              '*Preview is stopped when the PR is merged or closed.*',
            ].join('\n');

            const { data: comments } = await github.rest.issues.listComments({
              owner: context.repo.owner,
              repo: context.repo.repo,
              issue_number: context.issue.number,
            });
            const botComment = comments.find(c => c.body && c.body.includes('## mirrord Preview Environment - Metal Mart'));
            if (botComment) {
              await github.rest.issues.updateComment({
                owner: context.repo.owner,
                repo: context.repo.repo,
                comment_id: botComment.id,
                body,
              });
            } else {
              await github.rest.issues.createComment({
                owner: context.repo.owner,
                repo: context.repo.repo,
                issue_number: context.issue.number,
                body,
              });
            }

      - name: Post preview link to Slack
        uses: slackapi/slack-github-action@v1.27.0
        with:
          payload: |
            {
              "blocks": [
                {
                  "type": "header",
                  "text": { "type": "plain_text", "text": "mirrord Preview Environment - Metal Mart" }
                },
                {
                  "type": "section",
                  "fields": [
                    { "type": "mrkdwn", "text": "*PR:*\n<${{ github.event.pull_request.html_url }}|#${{ github.event.pull_request.number }} ${{ github.event.pull_request.title }}>" },
                    { "type": "mrkdwn", "text": "*Services:*\n${{ needs.detect-changes.outputs.services_list }}" },
                    { "type": "mrkdwn", "text": "*Preview URL:*\n<https://playground.metalbear.dev/shop|Open Preview>" },
                    { "type": "mrkdwn", "text": "*Header:*\n`baggage: mirrord=${{ env.PREVIEW_KEY }}`" }
                  ]
                }
              ]
            }
        env:
          SLACK_WEBHOOK_URL: ${{ secrets.SLACK_WEBHOOK_URL }}
          SLACK_WEBHOOK_TYPE: INCOMING_WEBHOOK

  # ─── Job 4: Stop all previews on merge/close ───
  preview-stop:
    name: Stop all previews on merge/close
    if: github.event.action == 'closed'
    runs-on: ubuntu-latest
    timeout-minutes: 5
    permissions:
      contents: read
      id-token: write
    steps:
      - name: Authenticate to GCP via Workload Identity Federation
        uses: google-github-actions/auth@v2
        with:
          workload_identity_provider: ${{ secrets.GCP_WIF_PROVIDER }}
          service_account: ${{ secrets.GCP_SERVICE_ACCOUNT }}

      - name: Get GKE credentials
        uses: google-github-actions/get-gke-credentials@v2
        with:
          cluster_name: playground-cluster-1
          location: us-central1-c
          project_id: playground-383912

      - name: Stop mirrord preview
        uses: metalbear-co/mirrord-preview@master
        with:
          action: stop
          key: ${{ env.PREVIEW_KEY }}