fix: Using Java 8 in release and nightly builds (#573)

* fix: Using Java 8 in release and nightly builds

* fix: Removing env variable manipulation from tests

* Downgraded to mockito 2; Using wrapper classes to mock ADC

Author: hiranya911

.github/workflows/ci.yml

@@ -19,13 +19,17 @@ jobs:
   build:
     runs-on: ubuntu-latest
 
+    strategy:
+      matrix:
+        java-version: [7, 8, 11]
+
     steps:
     - uses: actions/checkout@v1
 
-    - name: Set up JDK 1.7
+    - name: Set up JDK
       uses: actions/setup-java@v1
       with:
-        java-version: 1.7
+        java-version: ${{ matrix.java-version }}
 
     # Does the following:
     #  1. Runs the Checkstyle plugin (validate phase)

.github/workflows/nightly.yml

@@ -33,10 +33,10 @@ jobs:
       with:
         ref: ${{ github.event.client_payload.ref || github.ref }}
 
-    - name: Set up JDK 1.7
+    - name: Set up JDK 1.8
       uses: actions/setup-java@v1
       with:
-        java-version: 1.7
+        java-version: 1.8
 
     - name: Compile, test and package
       run: ./.github/scripts/package_artifacts.sh
@@ -63,7 +63,7 @@ jobs:
         subject: 'Nightly build ${{github.run_id}} of ${{github.repository}} failed!'
         html: >
           <b>Nightly workflow ${{github.run_id}} failed on: ${{github.repository}}</b>
-          <br /><br />Navigate to the 
+          <br /><br />Navigate to the
           <a href="https://github.com/firebase/firebase-admin-java/actions/runs/${{github.run_id}}">failed workflow</a>.
       continue-on-error: true
 
@@ -78,6 +78,6 @@ jobs:
         subject: 'Nightly build ${{github.run_id}} of ${{github.repository}} cancelled!'
         html: >
           <b>Nightly workflow ${{github.run_id}} cancelled on: ${{github.repository}}</b>
-          <br /><br />Navigate to the 
+          <br /><br />Navigate to the
           <a href="https://github.com/firebase/firebase-admin-java/actions/runs/${{github.run_id}}">cancelled workflow</a>.
       continue-on-error: true

.github/workflows/release.yml

@@ -44,10 +44,10 @@ jobs:
       with:
         ref: ${{ github.event.client_payload.ref || github.ref }}
 
-    - name: Set up JDK 1.7
+    - name: Set up JDK 1.8
       uses: actions/setup-java@v1
       with:
-        java-version: 1.7
+        java-version: 1.8
 
     - name: Compile, test and package
       run: ./.github/scripts/package_artifacts.sh
@@ -82,10 +82,10 @@ jobs:
     - name: Checkout source for publish
       uses: actions/checkout@v2
 
-    - name: Set up JDK 1.7
+    - name: Set up JDK 1.8
       uses: actions/setup-java@v1
       with:
-        java-version: 1.7
+        java-version: 1.8
 
     - name: Publish preflight check
       id: preflight

src/main/java/com/google/firebase/FirebaseApp.java

@@ -35,6 +35,7 @@
 import com.google.common.base.Strings;
 import com.google.common.collect.ImmutableList;
 import com.google.firebase.internal.ApiClientUtils;
+import com.google.firebase.internal.FirebaseProcessEnvironment;
 import com.google.firebase.internal.FirebaseScheduledExecutor;
 import com.google.firebase.internal.FirebaseService;
 import com.google.firebase.internal.ListenableFuture2ApiFuture;
@@ -292,10 +293,10 @@ String getProjectId() {
 
     // Try to get project ID from the environment.
     if (Strings.isNullOrEmpty(projectId)) {
-      projectId = System.getenv("GOOGLE_CLOUD_PROJECT");
+      projectId = FirebaseProcessEnvironment.getenv("GOOGLE_CLOUD_PROJECT");
     }
     if (Strings.isNullOrEmpty(projectId)) {
-      projectId = System.getenv("GCLOUD_PROJECT");
+      projectId = FirebaseProcessEnvironment.getenv("GCLOUD_PROJECT");
     }
     return projectId;
   }
@@ -563,7 +564,7 @@ enum State {
   }
 
   private static FirebaseOptions getOptionsFromEnvironment() throws IOException {
-    String defaultConfig = System.getenv(FIREBASE_CONFIG_ENV_VAR);
+    String defaultConfig = FirebaseProcessEnvironment.getenv(FIREBASE_CONFIG_ENV_VAR);
     if (Strings.isNullOrEmpty(defaultConfig)) {
       return FirebaseOptions.builder()
           .setCredentials(APPLICATION_DEFAULT_CREDENTIALS)

src/main/java/com/google/firebase/FirebaseOptions.java

@@ -29,6 +29,7 @@
 import com.google.common.base.Suppliers;
 import com.google.common.collect.ImmutableList;
 import com.google.firebase.internal.ApiClientUtils;
+import com.google.firebase.internal.ApplicationDefaultCredentialsProvider;
 import com.google.firebase.internal.FirebaseThreadManagers;
 import com.google.firebase.internal.NonNull;
 import com.google.firebase.internal.Nullable;
@@ -64,7 +65,8 @@ public final class FirebaseOptions {
         @Override
         public GoogleCredentials get() {
           try {
-            return GoogleCredentials.getApplicationDefault().createScoped(FIREBASE_SCOPES);
+            return ApplicationDefaultCredentialsProvider.getApplicationDefault()
+                .createScoped(FIREBASE_SCOPES);
           } catch (IOException e) {
             throw new IllegalStateException(e);
           }

src/main/java/com/google/firebase/auth/internal/Utils.java

@@ -18,6 +18,7 @@
 
 import com.google.common.annotations.VisibleForTesting;
 import com.google.common.base.Strings;
+import com.google.firebase.internal.FirebaseProcessEnvironment;
 
 public class Utils {
   @VisibleForTesting
@@ -28,7 +29,7 @@ public static boolean isEmulatorMode() {
   }
 
   public static String getEmulatorHost() {
-    return System.getenv(AUTH_EMULATOR_HOST);
+    return FirebaseProcessEnvironment.getenv(AUTH_EMULATOR_HOST);
   }
 
 }

src/main/java/com/google/firebase/database/util/EmulatorHelper.java

@@ -22,6 +22,7 @@
 import com.google.firebase.database.core.RepoInfo;
 import com.google.firebase.database.utilities.ParsedUrl;
 import com.google.firebase.database.utilities.Utilities;
+import com.google.firebase.internal.FirebaseProcessEnvironment;
 
 public final class EmulatorHelper {
 
@@ -33,7 +34,7 @@ private EmulatorHelper() {
       "FIREBASE_DATABASE_EMULATOR_HOST";
 
   public static String getEmulatorHostFromEnv() {
-    return System.getenv(FIREBASE_RTDB_EMULATOR_HOST_ENV_VAR);
+    return FirebaseProcessEnvironment.getenv(FIREBASE_RTDB_EMULATOR_HOST_ENV_VAR);
   }
 
   @VisibleForTesting

src/main/java/com/google/firebase/internal/ApplicationDefaultCredentialsProvider.java

@@ -0,0 +1,46 @@
+/*
+ * Copyright 2021 Google Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.firebase.internal;
+
+import com.google.auth.oauth2.GoogleCredentials;
+import java.io.IOException;
+
+/**
+ * Provides a hook to override application default credentials (ADC) lookup for tests. ADC has
+ * a dependency on environment variables, and Java famously doesn't support environment variable
+ * manipulation at runtime. With this class, the test cases that require ADC has a way to register
+ * their own mock credentials as ADC.
+ *
+ * <p>Once we are able to upgrade to Mockito 3.x (requires Java 8+), we can drop this class
+ * altogether, and use Mockito tools to mock the behavior of the GoogleCredentials static methods.
+ */
+public class ApplicationDefaultCredentialsProvider {
+
+  private static GoogleCredentials cachedCredentials;
+
+  public static GoogleCredentials getApplicationDefault() throws IOException {
+    if (cachedCredentials != null) {
+      return cachedCredentials;
+    }
+
+    return GoogleCredentials.getApplicationDefault();
+  }
+
+  public static void setApplicationDefault(GoogleCredentials credentials) {
+    cachedCredentials = credentials;
+  }
+}

src/main/java/com/google/firebase/internal/FirebaseProcessEnvironment.java

@@ -0,0 +1,46 @@
+/*
+ * Copyright 2021 Google Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.firebase.internal;
+
+import com.google.common.base.Strings;
+import java.util.Map;
+import java.util.concurrent.ConcurrentHashMap;
+
+/**
+ * A utility for overriding environment variables during tests.
+ */
+public class FirebaseProcessEnvironment {
+
+  private static final Map<String, String> localCache = new ConcurrentHashMap<>();
+
+  public static String getenv(String name) {
+    String cachedValue = localCache.get(name);
+    if (!Strings.isNullOrEmpty(cachedValue)) {
+      return  cachedValue;
+    }
+
+    return System.getenv(name);
+  }
+
+  public static void setenv(String name, String value) {
+    localCache.put(name, value);
+  }
+
+  public static void clearCache() {
+    localCache.clear();
+  }
+}