Add composite index testing guidance to ReadMe (#5421)

Author: milaGGL

.github/workflows/ci_tests.yml

@@ -121,22 +121,6 @@ jobs:
         with:
           credentials_json: ${{ secrets.GCP_SERVICE_ACCOUNT }}
       - uses: google-github-actions/setup-gcloud@v0
-      # create composite indexes with Terraform
-      - name: Setup Terraform 
-        if: contains(matrix.module, ':firebase-firestore')
-        uses: hashicorp/setup-terraform@v2
-      - name: Terraform Init
-        if: contains(matrix.module, ':firebase-firestore')
-        run: |
-          cd firebase-firestore
-          terraform init
-        continue-on-error: true
-      - name: Terraform Apply
-        if: github.event_name == 'pull_request' && contains(matrix.module, ':firebase-firestore')
-        run: |
-          cd firebase-firestore
-          terraform apply -var-file=../google-services.json -auto-approve
-        continue-on-error: true
       - name: ${{ matrix.module }} Integ Tests
         env:
           FIREBASE_CI: 1
@@ -178,6 +162,34 @@ jobs:
         with:
           credentials_json: ${{ secrets.GCP_SERVICE_ACCOUNT }}
       - uses: google-github-actions/setup-gcloud@v0
+            
+      # create composite indexes with Terraform
+      - name: Setup Terraform 
+        uses: hashicorp/setup-terraform@v2
+      - name: Terraform Init
+        run: |
+          cd firebase-firestore
+          terraform init
+        continue-on-error: true
+      - name: Terraform Apply
+        if: github.event_name == 'pull_request'
+        run: |
+          cd firebase-firestore
+
+          # Define a temporary file, redirect both stdout and stderr to the file
+          output_file=$(mktemp)
+          if ! terraform apply -var-file=../google-services.json -auto-approve > "$output_file" 2>&1 ; then
+            cat "$output_file"
+            if cat "$output_file" | grep -q "index already exists"; then
+              echo "==================================================================================="
+              echo -e "\e[93m\e[1mTerraform apply failed due to index already exists; We can safely ignore this error.\e[0m"
+              echo "==================================================================================="
+            fi
+            exit 1
+          fi
+          rm -f "$output_file"
+        continue-on-error: true
+
       - name: Firestore Named DB Integ Tests
         env:
           FIREBASE_CI: 1

firebase-firestore/README.md

@@ -87,6 +87,28 @@ Run:
 ./gradlew :firebase-firestore:deviceCheck
 ```
 
+### Testing composite index query against production
+#### Setting Up the Environment:
+1. Create a `google-services.json` file in the root directory. This file should contain your target Firebase project's configuration.
+2. If not already logged in, authenticate with your Google Cloud Platform (GCP) account using
+`gcloud auth application-default login`. You can check your logged-in accounts by running
+`gcloud auth list`.
+3. Navigate to the `firebase-firestore` directory, create composite indexes by running:
+```
+terraform init
+terraform apply -var-file=../google-services.json -auto-approve
+```
+Note: If the index creation encounters issues, such as concurrent operations, consider running the
+index creation process again. Error messages indicating that indexes have already been created can
+be safely disregarded.
+
+#### Adding new composite index query tests
+1. To create a new composite index for local development, click on the provided link in the test
+error message, which will direct you to the Firebase Console.
+2. Add the newly created composite index to the `firestore_index_config.tf` file. The "__name__"
+field is not required to be explicitly added to the file, as the index creation will auto complete
+it on behalf.
+
 ## Code Formatting
 
 Run below to format Java code:

firebase-firestore/src/androidTest/java/com/google/firebase/firestore/CompositeIndexQueryTest.java

@@ -30,14 +30,13 @@
  * Guidance for Creating Tests:
  * ----------------------------
  * When creating tests that require composite indexes, it is recommended to utilize the
- * "CompositeIndexTestHelper" class. This utility class provides methods for creating
- * and setting test documents and running queries with ease, ensuring proper data
- * isolation and query construction.
+ * "CompositeIndexTestHelper" class. This utility class provides methods for creating and setting
+ * test documents and running queries with ease, ensuring proper data isolation and query
+ * construction.
  *
- * Please remember to update the main index configuration file (firestore_index_config.tf)
- * with any new composite indexes needed for the tests. This ensures synchronization with
- * other testing environments, including CI. You can generate the required index link by
- * clicking on the Firebase console link in the error message while running tests locally.
+ * To get started, please refer to the instructions provided in the README file. This will guide
+ * you through setting up your local testing environment and updating the Terraform configuration
+ * with any new composite indexes required for your testing scenarios.
  */
 @RunWith(AndroidJUnit4.class)
 public class CompositeIndexQueryTest {