Add a recipe to show how to consume a ScopedArtifact

Bug: NA
Test: GradleRecipeTest
Change-Id: Ia3761f8b190001c5d17dab02786042d7f1b120fd

BUILD

@@ -59,6 +59,10 @@ recipe_test(
     name = "getMultipleArtifact",
 )
 
+recipe_test(
+    name = "getScopedArtifacts",
+)
+
 recipe_test(
     name = "getSingleArtifact",
 )

recipes/getScopedArtifacts/README.md

@@ -0,0 +1,52 @@
+# Consuming scoped artifacts
+
+This recipe shows how to add a task per variant to get and check a
+[ScopedArtifact](https://developer.android.com/reference/tools/gradle-api/current/com/android/build/api/artifact/ScopedArtifact).
+This recipe uses `ScopedArtifact.CLASSES` as an example, but the code is similar for other
+`ScopedArtifact` types.
+
+This recipe contains the following directories :
+
+| Module                     | Content                                                     |
+|----------------------------|-------------------------------------------------------------|
+| [build-logic](build-logic) | Contains the Project plugin that is the core of the recipe. |
+| [app](app)                 | An Android application that has the plugin applied.         |
+
+
+The [build-logic](build-logic) sub-project contains the
+[`CustomPlugin`](build-logic/plugins/src/main/kotlin/CustomPlugin.kt) and
+[`CheckClassesTask`](build-logic/plugins/src/main/kotlin/CheckClassesTask.kt) classes.
+
+[`CustomPlugin`](build-logic/plugins/src/main/kotlin/CustomPlugin.kt) registers an instance of the
+`CheckClassesTask` per variant and sets its `CLASSES` inputs via the code below,
+which automatically adds a dependency on any tasks producing `CLASSES` artifacts. When
+getting the final value of a scoped artifact, a Task must provide two input fields per scope, one
+for a list of jars and the other for a list of directories.
+
+```
+variant.artifacts
+    .forScope(ScopedArtifacts.Scope.PROJECT)
+    .use(taskProvider)
+    .toGet(
+        ScopedArtifact.CLASSES,
+        CheckClassesTask::projectJars,
+        CheckClassesTask::projectDirectories,
+    )
+    
+variant.artifacts
+    .forScope(ScopedArtifacts.Scope.ALL)
+    .use(taskProvider)
+    .toGet(
+        ScopedArtifact.CLASSES,
+        CheckClassesTask::allJars,
+        CheckClassesTask::allDirectories,
+    )
+```
+
+In practice, a task could consider only the `PROJECT` scope or only the `ALL` scope (though
+the `PROJECT` scope is a subset of the `ALL` scope). 
+
+[`CheckClassesTask`](build-logic/plugins/src/main/kotlin/CheckClassesTask.kt) does a trivial
+verification of the classes.
+
+To run the recipe : `gradlew checkDebugClasses`

recipes/getScopedArtifacts/app/build.gradle.kts

@@ -0,0 +1,37 @@
+/*
+ * Copyright 2023 The Android Open Source Project
+ *
+ * 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
+ *
+ *     https://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.
+ */
+
+plugins {
+    alias(libs.plugins.android.application)
+    alias(libs.plugins.kotlin.android)
+    id("android.recipes.custom_plugin")
+}
+
+android {
+    namespace = "com.example.android.recipes.getscopedartifacts"
+    compileSdk = $COMPILE_SDK
+    defaultConfig {
+       minSdk = $MINIMUM_SDK
+       targetSdk = $COMPILE_SDK
+       versionCode = 1
+    }
+}
+
+java {
+    toolchain {
+        languageVersion.set(JavaLanguageVersion.of(17))
+    }
+}

recipes/getScopedArtifacts/app/src/main/AndroidManifest.xml

@@ -0,0 +1,17 @@
+<?xml version="1.0" encoding="utf-8"?>
+<manifest xmlns:android="http://schemas.android.com/apk/res/android">
+    <!--
+         Copyright 2023 The Android Open Source Project
+         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.
+    -->
+    <application android:label="Minimal">
+    </application>
+</manifest>

recipes/getScopedArtifacts/app/src/main/kotlin/com/example/android/recipes/getscopedartifacts/MainActivity.kt

@@ -0,0 +1,29 @@
+/*
+ * Copyright (C) 2023 The Android Open Source Project
+ *
+ * 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.example.android.recipes.getscopedartifacts
+
+import android.app.Activity
+import android.os.Bundle
+import android.widget.TextView
+
+class MainActivity : Activity() {
+    override fun onCreate(savedInstanceState: Bundle?) {
+        super.onCreate(savedInstanceState)
+        val label = TextView(this)
+        label.setText("Hello World!")
+        setContentView(label)
+    }
+}

recipes/getScopedArtifacts/build-logic/gradle.properties

@@ -0,0 +1,2 @@
+# Gradle properties are not passed to included builds https://github.com/gradle/gradle/issues/2534
+org.gradle.parallel=true

recipes/getScopedArtifacts/build-logic/gradle/libs.versions.toml

@@ -0,0 +1,9 @@
+[versions]
+androidGradlePlugin = $AGP_VERSION
+kotlin = $KOTLIN_VERSION
+
+[libraries]
+android-gradlePlugin-api = { group = "com.android.tools.build", name = "gradle-api", version.ref = "androidGradlePlugin" }
+
+[plugins]
+kotlin-jvm = { id = "org.jetbrains.kotlin.jvm", version.ref = "kotlin" }

recipes/getScopedArtifacts/build-logic/plugins/build.gradle.kts

@@ -0,0 +1,40 @@
+/*
+ * Copyright 2023 The Android Open Source Project
+ *
+ * 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
+ *
+ *     https://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.
+ */
+
+plugins {
+    `java-gradle-plugin`
+    alias(libs.plugins.kotlin.jvm)
+}
+
+java {
+    toolchain {
+        languageVersion.set(JavaLanguageVersion.of(17))
+    }
+}
+
+dependencies {
+    compileOnly(libs.android.gradlePlugin.api)
+    implementation(gradleKotlinDsl())
+}
+
+gradlePlugin {
+    plugins {
+        create("customPlugin") {
+            id = "android.recipes.custom_plugin"
+            implementationClass = "CustomPlugin"
+        }
+    }
+}

recipes/getScopedArtifacts/build-logic/plugins/src/main/kotlin/CheckClassesTask.kt

@@ -0,0 +1,110 @@
+/*
+ * Copyright 2023 The Android Open Source Project
+ *
+ *   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
+ *
+ *       https://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.
+ */
+
+import org.gradle.api.DefaultTask
+import org.gradle.api.file.Directory
+import org.gradle.api.file.DirectoryProperty
+import org.gradle.api.file.RegularFile
+import org.gradle.api.provider.ListProperty
+import org.gradle.api.tasks.InputFiles
+import org.gradle.api.tasks.OutputDirectory
+import org.gradle.api.tasks.TaskAction
+import java.io.File
+import java.lang.RuntimeException
+
+/**
+ * This task does a trivial check of a variant's classes.
+ */
+abstract class CheckClassesTask: DefaultTask() {
+
+    // In order for the task to be up-to-date when the inputs have not changed,
+    // the task must declare an output, even if it's not used. Tasks with no
+    // output are always run regardless of whether the inputs changed
+    @get:OutputDirectory
+    abstract val output: DirectoryProperty
+
+    /**
+     * Project scope, not including dependencies.
+     */
+    @get:InputFiles
+    abstract val projectDirectories: ListProperty<Directory>
+
+    /**
+     * Project scope, not including dependencies.
+     */
+    @get:InputFiles
+    abstract val projectJars: ListProperty<RegularFile>
+
+    /**
+     * Full scope, including project scope and all dependencies.
+     */
+    @get:InputFiles
+    abstract val allDirectories: ListProperty<Directory>
+
+    /**
+     * Full scope, including project scope and all dependencies.
+     */
+    @get:InputFiles
+    abstract val allJars: ListProperty<RegularFile>
+
+    /**
+     * This task does a trivial check of the classes, but a similar task could be
+     * written to perform useful verification.
+     */
+    @TaskAction
+    fun taskAction() {
+
+        // Check projectDirectories
+        if (projectDirectories.get().isEmpty()) {
+            throw RuntimeException("Expected projectDirectories not to be empty")
+        }
+        projectDirectories.get().firstOrNull()?.let {
+            if (!it.asFile.walk().toList().any { file -> file.name == "MainActivity.class" }) {
+                throw RuntimeException("Expected MainActivity.class in projectDirectories")
+            }
+        }
+
+        // Check projectJars. We expect projectJars to include the project's R.jar but not jars
+        // from dependencies (e.g., the kotlin stdlib jar)
+        val projectJarFileNames = projectJars.get().map { it.asFile.name }
+        if (!projectJarFileNames.contains("R.jar")) {
+            throw RuntimeException("Expected project jars to contain R.jar")
+        }
+        if (projectJarFileNames.any { it.startsWith("kotlin-stdlib") }) {
+            throw RuntimeException("Did not expected projectJars to contain kotlin stdlib")
+        }
+
+        // Check allDirectories
+        if (allDirectories.get().isEmpty()) {
+            throw RuntimeException("Expected allDirectories not to be empty")
+        }
+        allDirectories.get().firstOrNull()?.let {
+            if (!it.asFile.walk().toList().any { file -> file.name == "MainActivity.class" }) {
+                throw RuntimeException("Expected MainActivity.class in allDirectories")
+            }
+        }
+
+        // Check allJars. We expect allJars to include jars from the project *and* its dependencies
+        // (e.g., the kotlin stdlib jar).
+        val allJarFileNames = allJars.get().map { it.asFile.name }
+        if (!allJarFileNames.contains("R.jar")) {
+            throw RuntimeException("Expected allJars to contain R.jar")
+        }
+        if (!allJarFileNames.any { it.startsWith("kotlin-stdlib") }) {
+            throw RuntimeException("Expected allJars to contain kotlin stdlib")
+        }
+    }
+}

recipes/getScopedArtifacts/build-logic/plugins/src/main/kotlin/CustomPlugin.kt

@@ -0,0 +1,79 @@
+/*
+ * Copyright 2023 The Android Open Source Project
+ *
+ *   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
+ *
+ *       https://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.
+ */
+
+import com.android.build.api.artifact.ScopedArtifact
+import com.android.build.api.variant.AndroidComponentsExtension
+import com.android.build.api.variant.ScopedArtifacts
+import com.android.build.gradle.AppPlugin
+import org.gradle.api.Plugin
+import org.gradle.api.Project
+import org.gradle.kotlin.dsl.register
+
+/**
+ * This custom plugin creates a task per variant that checks the variant's classes
+ */
+class CustomPlugin : Plugin<Project> {
+    override fun apply(project: Project) {
+
+        // Registers a callback on the application of the Android Application plugin.
+        // This allows the CustomPlugin to work whether it's applied before or after
+        // the Android Application plugin.
+        project.plugins.withType(AppPlugin::class.java) {
+
+            // Queries for the extension set by the Android Application plugin.
+            val androidComponents =
+                project.extensions.getByType(AndroidComponentsExtension::class.java)
+
+            // Registers a callback to be called, when a new variant is configured
+            androidComponents.onVariants { variant ->
+
+                // Registers a new task to verify the app classes.
+                val taskName = "check${variant.name}Classes"
+                val taskProvider = project.tasks.register<CheckClassesTask>(taskName) {
+                    output.set(
+                        project.layout.buildDirectory.dir("intermediates/$taskName")
+                    )
+                }
+
+                // Sets the task's projectJars and projectDirectories inputs to the
+                // ScopeArtifacts.Scope.PROJECT ScopedArtifact.CLASSES artifacts. This
+                // automatically creates a dependency between this task and any tasks
+                // generating classes in the PROJECT scope.
+                variant.artifacts
+                    .forScope(ScopedArtifacts.Scope.PROJECT)
+                    .use(taskProvider)
+                    .toGet(
+                        ScopedArtifact.CLASSES,
+                        CheckClassesTask::projectJars,
+                        CheckClassesTask::projectDirectories,
+                    )
+
+                // Sets this task's allJars and allDirectories inputs to the
+                // ScopeArtifacts.Scope.ALL ScopedArtifact.CLASSES artifacts. This
+                // automatically creates a dependency between this task and any tasks
+                // generating classes.
+                variant.artifacts
+                    .forScope(ScopedArtifacts.Scope.ALL)
+                    .use(taskProvider)
+                    .toGet(
+                        ScopedArtifact.CLASSES,
+                        CheckClassesTask::allJars,
+                        CheckClassesTask::allDirectories,
+                    )
+            }
+        }
+    }
+}