Fix copyRootGoogleServices task (#5895)

Per [b/322356188](https://b.corp.google.com/issues/322356188),

This fixes the issues with the `copyRootGoogleServices` task. 

Namely, it seems there are various tasks in the pipeline that have
_implicit_ dependencies on source files- which gradle doesn't like. To
fix this, we just ensure `copyRootGoogleServices` is set as a dependency
of them all.

This PR also moves the `copyRootGoogleServices` task into our android
library plugin- to keep everything together.

Author: daymxn

appcheck/firebase-appcheck-debug-testing/firebase-appcheck-debug-testing.gradle

@@ -14,6 +14,7 @@
 
 plugins {
     id 'firebase-library'
+    id 'copy-google-services'
 }
 
 firebaseLibrary {
@@ -72,10 +73,3 @@ dependencies {
     androidTestImplementation 'junit:junit:4.13-beta-2'
     androidTestImplementation 'org.mockito:mockito-core:2.25.0'
 }
-
-// ==========================================================================
-// Copy from here down if you want to use the google-services plugin in your
-// androidTest integration tests.
-// ==========================================================================
-ext.packageName = "com.google.firebase.appcheck.debug.testing"
-apply from: '../../gradle/googleServices.gradle'

appcheck/firebase-appcheck/test-app/test-app.gradle

@@ -14,6 +14,7 @@
 
 apply plugin: 'com.android.application'
 apply plugin: 'com.google.gms.google-services'
+apply plugin: 'copy-google-services'
 
 android {
     compileSdkVersion project.compileSdkVersion
@@ -45,10 +46,3 @@ dependencies {
     implementation 'androidx.constraintlayout:constraintlayout:1.1.3'
     implementation 'com.google.android.gms:play-services-tasks:18.0.1'
 }
-
-// ==========================================================================
-// Copy from here down if you want to use the google-services plugin in your
-// androidTest integration tests.
-// ==========================================================================
-ext.packageName = "com.googletest.firebase.appcheck"
-apply from: '../../../gradle/googleServices.gradle'

buildSrc/build.gradle.kts

@@ -94,6 +94,10 @@ gradlePlugin {
             id = "firebase-vendor"
             implementationClass = "com.google.firebase.gradle.plugins.VendorPlugin"
         }
+        register("copyGoogleServicesPlugin") {
+            id = "copy-google-services"
+            implementationClass = "com.google.firebase.gradle.plugins.CopyGoogleServicesPlugin"
+        }
     }
 }
 

buildSrc/src/main/java/com/google/firebase/gradle/plugins/BaseFirebaseLibraryPlugin.kt

@@ -16,6 +16,7 @@
 
 package com.google.firebase.gradle.plugins
 
+import com.android.build.gradle.LibraryExtension
 import com.google.firebase.gradle.plugins.ci.Coverage
 import java.io.File
 import java.nio.file.Paths
@@ -31,6 +32,7 @@ import org.gradle.kotlin.dsl.apply
 import org.gradle.kotlin.dsl.configure
 import org.gradle.kotlin.dsl.create
 import org.gradle.kotlin.dsl.findByType
+import org.gradle.kotlin.dsl.getByType
 import org.gradle.kotlin.dsl.provideDelegate
 import org.gradle.kotlin.dsl.register
 import org.w3c.dom.Element
@@ -280,3 +282,19 @@ val FirebaseLibraryExtension.latestVersion: ModuleVersion
         "Invalid format for ModuleVersion for module '$artifactName':\n $latestVersion"
       )
   }
+
+/**
+ * Fetches the namespace for this SDK from the [LibraryExtension].
+ *
+ * eg;
+ *
+ * ```
+ * com.googletest.firebase.appdistribution
+ * ```
+ *
+ * @throws RuntimeException when the project doesn't have a defined namespace
+ */
+val FirebaseLibraryExtension.namespace: String
+  get() =
+    project.extensions.getByType<LibraryExtension>().namespace
+      ?: throw RuntimeException("Project doesn't have a defined namespace: ${project.path}")

buildSrc/src/main/java/com/google/firebase/gradle/plugins/CopyGoogleServicesPlugin.kt

@@ -0,0 +1,94 @@
+/*
+ * Copyright 2024 Google LLC
+ *
+ * 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.gradle.plugins
+
+import com.android.build.gradle.BaseExtension
+import java.io.File
+import org.gradle.api.Plugin
+import org.gradle.api.Project
+import org.gradle.api.tasks.Copy
+import org.gradle.kotlin.dsl.getByType
+import org.gradle.kotlin.dsl.register
+
+/**
+ * Copies the root google-services.json into the project directory during build time.
+ *
+ * If a path is provided via `FIREBASE_GOOGLE_SERVICES_PATH`, that will be used instead. The file
+ * will also be renamed to `google-services.json`, so provided files do *not* need to be properly
+ * named.
+ *
+ * Will also register the `com.google.gms.google-services` plugin if a test task is running.
+ */
+abstract class CopyGoogleServicesPlugin : Plugin<Project> {
+  override fun apply(project: Project) {
+    val copyRootGoogleServices = registerCopyRootGoogleServicesTask(project)
+
+    project.allprojects {
+      // fixes dependencies with gradle tasks that do not properly dependOn `preBuild`
+      tasks.configureEach {
+        if (name !== "copyRootGoogleServices") dependsOn(copyRootGoogleServices)
+      }
+    }
+
+    if (project.isRunningTestTask()) {
+      println("[test] applying google-services plugin")
+      project.plugins.apply("com.google.gms.google-services")
+    }
+  }
+
+  private fun Project.isRunningTestTask(): Boolean {
+    val testTasks = listOf("AndroidTest", "connectedCheck", "deviceCheck")
+
+    return gradle.startParameter.taskNames.any { testTasks.any(it::contains) }
+  }
+
+  private fun registerCopyRootGoogleServicesTask(project: Project) =
+    project.tasks.register<Copy>("copyRootGoogleServices") {
+      val sourcePath =
+        System.getenv("FIREBASE_GOOGLE_SERVICES_PATH") ?: "${project.rootDir}/google-services.json"
+
+      val library = project.extensions.getByType<BaseExtension>()
+
+      val targetPackageLine = "\"package_name\": \"${library.namespace}\""
+      val packageLineRegex = Regex("\"package_name\":\\s+\".*\"")
+
+      from(sourcePath)
+      into(project.projectDir)
+
+      rename { "google-services.json" }
+
+      if (fileIsMissingPackageName(sourcePath, targetPackageLine)) {
+        /**
+         * Modifies `google-services.json` such that all declared `package_name` entries are
+         * replaced with the project's namespace. This tricks the google services plugin into
+         * thinking that the target `package_name` is a Firebase App and allows connection to the
+         * Firebase project.
+         *
+         * Note that all events generated from that app will then go to whatever the first client
+         * entry is in the `google-services.json` file.
+         */
+        filter { it.replace(packageLineRegex, targetPackageLine) }
+      }
+    }
+
+  private fun fileIsMissingPackageName(path: String, targetPackageLine: String): Boolean {
+    val file = File(path)
+    if (!file.exists()) return true
+
+    return !file.readText().contains(targetPackageLine)
+  }
+}

buildSrc/src/main/java/com/google/firebase/gradle/plugins/FirebaseLibraryPlugin.kt

@@ -36,6 +36,7 @@ import org.gradle.kotlin.dsl.register
 import org.gradle.kotlin.dsl.withType
 import org.jetbrains.kotlin.gradle.tasks.KotlinCompile
 
+// TODO() maybe rename to FirebaseAndroidLibraryPlugin; makes more sense alongside java one
 class FirebaseLibraryPlugin : BaseFirebaseLibraryPlugin() {
 
   override fun apply(project: Project) {
@@ -48,10 +49,12 @@ class FirebaseLibraryPlugin : BaseFirebaseLibraryPlugin() {
     // reduce the likelihood of kotlin module files colliding.
     project.tasks.withType<KotlinCompile> {
       kotlinOptions.freeCompilerArgs = listOf("-module-name", kotlinModuleName(project))
+      kotlinOptions.jvmTarget = "1.8"
     }
 
     project.apply<DackkaPlugin>()
     project.apply<GitSubmodulePlugin>()
+
     project.tasks.getByName("preBuild").dependsOn("updateGitSubmodules")
   }
 

firebase-appdistribution/test-app/test-app.gradle

@@ -16,6 +16,7 @@ plugins {
     id 'kotlin-android'
     id 'com.google.gms.google-services'
     id 'com.google.firebase.appdistribution'
+    id 'copy-google-services'
 }
 
 android {
@@ -96,7 +97,3 @@ dependencies {
 
     testImplementation 'junit:junit:4.13.2'
 }
-
-// This allows the app to connect to Firebase on the CI.
-ext.packageName = "com.googletest.firebase.appdistribution.testapp"
-apply from: '../../gradle/googleServices.gradle'

firebase-config/bandwagoner/bandwagoner.gradle

@@ -17,6 +17,7 @@
 apply plugin: 'com.android.application'
 apply plugin: com.google.firebase.gradle.plugins.ci.device.FirebaseTestLabPlugin
 apply plugin: 'org.jetbrains.kotlin.android'
+apply plugin: 'copy-google-services'
 
 // Uncomment this line after adding a google-services.json file to the project.
 // apply plugin: 'com.google.gms.google-services'
@@ -112,6 +113,3 @@ dependencies {
     androidTestImplementation 'androidx.test.espresso:espresso-core:3.2.0'
     androidTestImplementation 'androidx.test.espresso:espresso-idling-resource:3.2.0'
 }
-
-ext.packageName = "com.googletest.firebase.remoteconfig.bandwagoner"
-apply from: '../../gradle/googleServices.gradle'

firebase-config/test-app/test-app.gradle.kts

@@ -24,6 +24,7 @@ plugins {
   id("com.google.gms.google-services")
   id("com.google.firebase.crashlytics")
   id("com.google.firebase.firebase-perf")
+  id("copy-google-services")
 }
 
 android {
@@ -90,8 +91,4 @@ dependencies {
   androidTestImplementation(libs.truth)
 }
 
-extra["packageName"] = "com.google.firebase.testing.config"
-
-apply(from = "../../gradle/googleServices.gradle")
-
 apply<FirebaseTestLabPlugin>()

firebase-database/firebase-database.gradle.kts

@@ -15,6 +15,7 @@
 plugins {
     id("firebase-library")
     id("kotlin-android")
+    id("copy-google-services")
 }
 
 firebaseLibrary {
@@ -93,7 +94,3 @@ dependencies {
     androidTestImplementation(libs.quickcheck)
     androidTestImplementation(libs.truth)
 }
-
-ext["packageName"] = "com.google.firebase.database"
-
-apply("../gradle/googleServices.gradle")