Skip deploy if environment variables are missing

.github/workflows/deploy-latest.yml

@@ -14,24 +14,46 @@ jobs:
   deploy:
     runs-on: ubuntu-latest
     steps:
+    - name: Check deployment prerequisites
+      id: deployment-prerequisites
+      env:
+        GCP_SA_KEY: ${{ secrets.GCP_SA_KEY }}
+        LATEST_DATASETTE_SECRET: ${{ secrets.LATEST_DATASETTE_SECRET }}
+      run: |
+        missing=()
+        for variable in GCP_SA_KEY LATEST_DATASETTE_SECRET; do
+          if [[ -z "${!variable:-}" ]]; then
+            missing+=("$variable")
+          fi
+        done
+        if (( ${#missing[@]} )); then
+          echo "::notice::Skipping deployment because required environment variables are missing: ${missing[*]}"
+          echo "available=false" >> "$GITHUB_OUTPUT"
+        else
+          echo "available=true" >> "$GITHUB_OUTPUT"
+        fi
     - name: Check out datasette
+      if: ${{ steps.deployment-prerequisites.outputs.available == 'true' }}
       uses: actions/checkout@v7
     - name: Set up Python
+      if: ${{ steps.deployment-prerequisites.outputs.available == 'true' }}
       uses: actions/setup-python@v6
       with:
         python-version: "3.13"
         cache: pip
     - name: Install Python dependencies
+      if: ${{ steps.deployment-prerequisites.outputs.available == 'true' }}
       run: |
         python -m pip install --upgrade pip
         python -m pip install . --group dev
         python -m pip install sphinx-to-sqlite==0.1a1
     - name: Run tests
-      if: ${{ github.ref == 'refs/heads/main' }}
+      if: ${{ steps.deployment-prerequisites.outputs.available == 'true' && github.ref == 'refs/heads/main' }}
       run: |
         pytest -n auto -m "not serial"
         pytest -m "serial"
     - name: Build fixtures.db and other files needed to deploy the demo
+      if: ${{ steps.deployment-prerequisites.outputs.available == 'true' }}
       run: |-
         python tests/fixtures.py \
           fixtures.db \
@@ -40,13 +62,14 @@ jobs:
           plugins \
           --extra-db-filename extra_database.db
     - name: Build docs.db
-      if: ${{ github.ref == 'refs/heads/main' }}
+      if: ${{ steps.deployment-prerequisites.outputs.available == 'true' && github.ref == 'refs/heads/main' }}
       run: |-
         cd docs
         DISABLE_SPHINX_INLINE_TABS=1 sphinx-build -b xml . _build
         sphinx-to-sqlite ../docs.db _build
         cd ..
     - name: Set up the alternate-route demo
+      if: ${{ steps.deployment-prerequisites.outputs.available == 'true' }}
       run: |
         echo '
         from datasette import hookimpl
@@ -58,6 +81,7 @@ jobs:
         ' > plugins/alternative_route.py
         cp fixtures.db fixtures2.db
     - name: And the counters writable stored query demo
+      if: ${{ steps.deployment-prerequisites.outputs.available == 'true' }}
       run: |
         cat > plugins/counters.py <<EOF
         from datasette import hookimpl
@@ -97,12 +121,15 @@ jobs:
     #     cat metadata.json
     - id: auth
       name: Authenticate to Google Cloud
+      if: ${{ steps.deployment-prerequisites.outputs.available == 'true' }}
       uses: google-github-actions/auth@v3
       with:
         credentials_json: ${{ secrets.GCP_SA_KEY }}
     - name: Set up Cloud SDK
+      if: ${{ steps.deployment-prerequisites.outputs.available == 'true' }}
       uses: google-github-actions/setup-gcloud@v3
     - name: Deploy to Cloud Run
+      if: ${{ steps.deployment-prerequisites.outputs.available == 'true' }}
       env:
         LATEST_DATASETTE_SECRET: ${{ secrets.LATEST_DATASETTE_SECRET }}
       run: |-
@@ -122,7 +149,7 @@ jobs:
             --service "datasette-latest$SUFFIX" \
             --secret $LATEST_DATASETTE_SECRET
     - name: Deploy to docs as well (only for main)
-      if: ${{ github.ref == 'refs/heads/main' }}
+      if: ${{ steps.deployment-prerequisites.outputs.available == 'true' && github.ref == 'refs/heads/main' }}
       run: |-
         # Deploy docs.db to a different service
         datasette publish cloudrun docs.db \