Build local maven repo when using local engine (#44243)

examples/flutter_gallery/android/app/build.gradle

@@ -73,14 +73,6 @@ flutter {
 }
 
 dependencies {
-    // TODO(egarciad): Remove these dependencies once https://github.com/flutter/flutter/issues/40866 is fixed.
-    implementation "androidx.annotation:annotation:1.1.0"
-    def lifecycle_version = "2.1.0"
-    implementation "androidx.lifecycle:lifecycle-common:$lifecycle_version"
-    implementation "androidx.lifecycle:lifecycle-common-java8:$lifecycle_version"
-    implementation "androidx.lifecycle:lifecycle-runtime:$lifecycle_version"
-    implementation "androidx.fragment:fragment:1.1.0"
-
     testImplementation 'junit:junit:4.12'
     androidTestImplementation 'androidx.test:rules:1.1.1'
     androidTestImplementation 'androidx.test:runner:1.1.1'

packages/flutter_tools/gradle/flutter.gradle

@@ -96,7 +96,6 @@ class FlutterPlugin implements Plugin<Project> {
     private String localEngine
     private String localEngineSrcPath
     private Properties localProperties
-    private File flutterJar
     private String engineVersion
 
     @Override
@@ -144,8 +143,9 @@ class FlutterPlugin implements Plugin<Project> {
             throw new GradleException("flutter.sdk must point to the Flutter SDK directory")
         }
 
-        engineVersion = Paths.get(flutterRoot.absolutePath, "bin", "internal", "engine.version")
-                .toFile().text.trim()
+        engineVersion = useLocalEngine()
+            ? "+" // Match any version since there's only one.
+            : "1.0.0-" + Paths.get(flutterRoot.absolutePath, "bin", "internal", "engine.version").toFile().text.trim()
 
         String flutterExecutableName = Os.isFamily(Os.FAMILY_WINDOWS) ? "flutter.bat" : "flutter"
         flutterExecutable = Paths.get(flutterRoot.absolutePath, "bin", flutterExecutableName).toFile();
@@ -178,32 +178,19 @@ class FlutterPlugin implements Plugin<Project> {
                 }
             }
         }
-
         if (useLocalEngine()) {
-            String engineOutPath = project.property('localEngineOut')
+            // This is required to pass the local engine to flutter build aot.
+            String engineOutPath = project.property('local-engine-out')
             File engineOut = project.file(engineOutPath)
             if (!engineOut.isDirectory()) {
-                throw new GradleException('localEngineOut must point to a local engine build')
-            }
-            Path baseEnginePath = Paths.get(engineOut.absolutePath)
-            flutterJar = baseEnginePath.resolve("flutter.jar").toFile()
-            if (!flutterJar.isFile()) {
-                throw new GradleException("Local engine jar not found: $flutterJar")
+                throw new GradleException('local-engine-out must point to a local engine build')
             }
             localEngine = engineOut.name
             localEngineSrcPath = engineOut.parentFile.parent
-            // The local engine is built for one of the build type.
-            // However, we use the same engine for each of the build types.
-            project.android.buildTypes.each {
-                addApiDependencies(project, it.name, project.files {
-                    flutterJar
-                })
         }
-        } else {
         project.android.buildTypes.each this.&addFlutterDependencies
         project.android.buildTypes.whenObjectAdded this.&addFlutterDependencies
     }
-    }
 
     /**
      * Adds the dependencies required by the Flutter project.
@@ -212,17 +199,24 @@ class FlutterPlugin implements Plugin<Project> {
      *    2. libflutter.so
      */
     void addFlutterDependencies(buildType) {
+        String flutterBuildMode = buildModeFor(buildType)
+        if (!supportsBuildMode(flutterBuildMode)) {
+            return
+        }
+        String repository = useLocalEngine()
+            ? project.property('local-engine-repo')
+            : MAVEN_REPO
+
         project.rootProject.allprojects {
             repositories {
                 maven {
-                    url MAVEN_REPO
+                    url repository
                 }
             }
         }
-        String flutterBuildMode = buildModeFor(buildType)
         // Add the embedding dependency.
         addApiDependencies(project, buildType.name,
-                "io.flutter:flutter_embedding_$flutterBuildMode:1.0.0-$engineVersion")
+                "io.flutter:flutter_embedding_$flutterBuildMode:$engineVersion")
 
         List<String> platforms = getTargetPlatforms().collect()
         // Debug mode includes x86 and x64, which are commonly used in emulators.
@@ -234,7 +228,7 @@ class FlutterPlugin implements Plugin<Project> {
             String arch = PLATFORM_ARCH_MAP[platform].replace("-", "_")
             // Add the `libflutter.so` dependency.
             addApiDependencies(project, buildType.name,
-                    "io.flutter:${arch}_$flutterBuildMode:1.0.0-$engineVersion")
+                    "io.flutter:${arch}_$flutterBuildMode:$engineVersion")
         }
     }
 
@@ -261,9 +255,6 @@ class FlutterPlugin implements Plugin<Project> {
             getPluginList().each this.&configurePluginProject
             return
         }
-        if (useLocalEngine()) {
-            throw new GradleException("Local engine isn't supported when building the plugins as AAR")
-        }
         project.repositories {
             maven {
                 url "${getPluginBuildDir()}/outputs/repo"
@@ -326,24 +317,13 @@ class FlutterPlugin implements Plugin<Project> {
             // In AGP 3.5, the embedding must be added as an API implementation,
             // so java8 features are desugared against the runtime classpath.
             // For more, see https://github.com/flutter/flutter/issues/40126
-            if (flutterJar) {
-                addApiDependencies(
-                    pluginProject,
-                    buildType.name,
-                    project.files {
-                        flutterJar
-                    }
-                )
+            if (!supportsBuildMode(flutterBuildMode)) {
                 return
             }
             addApiDependencies(
                 pluginProject,
                 buildType.name,
-                "io.flutter:flutter_embedding_$flutterBuildMode:1.0.0-$engineVersion",
-                {
-                    // Include the embedding transitive dependencies since plugins may depend on them.
-                    transitive = true
-                }
+                "io.flutter:flutter_embedding_$flutterBuildMode:$engineVersion"
             )
         }
         pluginProject.afterEvaluate {
@@ -425,7 +405,7 @@ class FlutterPlugin implements Plugin<Project> {
     }
 
     private Boolean useLocalEngine() {
-        return project.hasProperty('localEngineOut')
+        return project.hasProperty('local-engine-repo')
     }
 
     private Boolean isVerbose() {
@@ -452,6 +432,19 @@ class FlutterPlugin implements Plugin<Project> {
         return System.getProperty('build-plugins-as-aars') == 'true'
     }
 
+    // Returns true if the build mode is supported by the current call to Gradle.
+    // This only relevant when using a local engine. Because the engine
+    // is built for a specific mode, the call to Gradle must match that mode.
+    private Boolean supportsBuildMode(String flutterBuildMode) {
+        if (!useLocalEngine()) {
+            return true;
+        }
+        assert project.hasProperty('local-engine-build-mode')
+        // Don't configure dependencies for a build mode that the local engine
+        // doesn't support.
+        return project.property('local-engine-build-mode') == flutterBuildMode
+    }
+
     private void addCompileOnlyDependency(Project project, String variantName, Object dependency, Closure config = null) {
         if (project.state.failure) {
             return

packages/flutter_tools/lib/src/android/gradle.dart

@@ -6,6 +6,7 @@ import 'dart:async';
 
 import 'package:crypto/crypto.dart';
 import 'package:meta/meta.dart';
+import 'package:xml/xml.dart' as xml;
 
 import '../android/android_sdk.dart';
 import '../artifacts.dart';
@@ -282,8 +283,17 @@ Future<void> buildGradleApp({
   }
   if (artifacts is LocalEngineArtifacts) {
     final LocalEngineArtifacts localEngineArtifacts = artifacts;
-    printTrace('Using local engine: ${localEngineArtifacts.engineOutPath}');
-    command.add('-PlocalEngineOut=${localEngineArtifacts.engineOutPath}');
+    final Directory localEngineRepo = _getLocalEngineRepo(
+      engineOutPath: localEngineArtifacts.engineOutPath,
+      androidBuildInfo: androidBuildInfo,
+    );
+    printTrace(
+      'Using local engine: ${localEngineArtifacts.engineOutPath}\n'
+      'Local Maven repo: ${localEngineRepo.path}'
+    );
+    command.add('-Plocal-engine-repo=${localEngineRepo.path}');
+    command.add('-Plocal-engine-build-mode=${buildInfo.modeName}');
+    command.add('-Plocal-engine-out=${localEngineArtifacts.engineOutPath}');
   }
   if (target != null) {
     command.add('-Ptarget=$target');
@@ -504,8 +514,17 @@ Future<void> buildGradleAar({
   }
   if (artifacts is LocalEngineArtifacts) {
     final LocalEngineArtifacts localEngineArtifacts = artifacts;
-    printTrace('Using local engine: ${localEngineArtifacts.engineOutPath}');
-    command.add('-PlocalEngineOut=${localEngineArtifacts.engineOutPath}');
+    final Directory localEngineRepo = _getLocalEngineRepo(
+      engineOutPath: localEngineArtifacts.engineOutPath,
+      androidBuildInfo: androidBuildInfo,
+    );
+    printTrace(
+      'Using local engine: ${localEngineArtifacts.engineOutPath}\n'
+      'Local Maven repo: ${localEngineRepo.path}'
+    );
+    command.add('-Plocal-engine-repo=${localEngineRepo.path}');
+    command.add('-Plocal-engine-build-mode=${androidBuildInfo.buildInfo.modeName}');
+    command.add('-Plocal-engine-out=${localEngineArtifacts.engineOutPath}');
   }
 
   command.add(aarTask);
@@ -781,3 +800,110 @@ void _exitWithExpectedFileNotFound({
     'but the tool couldn\'t find it.'
   );
 }
+
+void _createSymlink(String targetPath, String linkPath) {
+  final File targetFile = fs.file(targetPath);
+  if (!targetFile.existsSync()) {
+    throwToolExit('The file $targetPath wasn\'t found in the local engine out directory.');
+  }
+  final File linkFile = fs.file(linkPath);
+  final Link symlink = linkFile.parent.childLink(linkFile.basename);
+  try {
+    symlink.createSync(targetPath, recursive: true);
+  } on FileSystemException catch (exception) {
+    throwToolExit(
+      'Failed to create the symlink $linkPath->$targetPath: $exception'
+    );
+  }
+}
+
+String _getLocalArtifactVersion(String pomPath) {
+  final File pomFile = fs.file(pomPath);
+  if (!pomFile.existsSync()) {
+    throwToolExit('The file $pomPath wasn\'t found in the local engine out directory.');
+  }
+  xml.XmlDocument document;
+  try {
+    document = xml.parse(pomFile.readAsStringSync());
+  } on xml.XmlParserException {
+    throwToolExit(
+      'Error parsing $pomPath. Please ensure that this is a valid XML document.'
+    );
+  } on FileSystemException {
+    throwToolExit(
+      'Error reading $pomPath. Please ensure that you have read permission to this'
+      'file and try again.');
+  }
+  final Iterable<xml.XmlElement> project = document.findElements('project');
+  assert(project.isNotEmpty);
+  for (xml.XmlElement versionElement in document.findAllElements('version')) {
+    if (versionElement.parent == project.first) {
+      return versionElement.text;
+    }
+  }
+  throwToolExit('Error while parsing the <version> element from $pomPath');
+  return null;
+}
+
+/// Returns the local Maven repository for a local engine build.
+/// For example, if the engine is built locally at <home>/engine/src/out/android_release_unopt
+/// This method generates symlinks in the temp directory to the engine artifacts
+/// following the convention specified on https://maven.apache.org/pom.html#Repositories
+Directory _getLocalEngineRepo({
+  @required String engineOutPath,
+  @required AndroidBuildInfo androidBuildInfo,
+}) {
+  assert(engineOutPath != null);
+  assert(androidBuildInfo != null);
+
+  final String abi = getEnumName(androidBuildInfo.targetArchs.first);
+  final Directory localEngineRepo = fs.systemTempDirectory
+    .createTempSync('flutter_tool_local_engine_repo.');
+
+  // Remove the local engine repo before the tool exits.
+  addShutdownHook(
+    () => localEngineRepo.deleteSync(recursive: true),
+    ShutdownStage.CLEANUP,
+  );
+
+  final String buildMode = androidBuildInfo.buildInfo.modeName;
+  final String artifactVersion = _getLocalArtifactVersion(
+    fs.path.join(
+      engineOutPath,
+      'flutter_embedding_$buildMode.pom',
+    )
+  );
+  for (String artifact in const <String>['pom', 'jar']) {
+    // The Android embedding artifacts.
+    _createSymlink(
+      fs.path.join(
+        engineOutPath,
+        'flutter_embedding_$buildMode.$artifact',
+      ),
+      fs.path.join(
+        localEngineRepo.path,
+        'io',
+        'flutter',
+        'flutter_embedding_$buildMode',
+        artifactVersion,
+        'flutter_embedding_$buildMode-$artifactVersion.$artifact',
+      ),
+    );
+    // The engine artifacts (libflutter.so).
+    _createSymlink(
+      fs.path.join(
+        engineOutPath,
+        '${abi}_$buildMode.$artifact',
+      ),
+      fs.path.join(
+        localEngineRepo.path,
+        'io',
+        'flutter',
+        '${abi}_$buildMode',
+        artifactVersion,
+        '${abi}_$buildMode-$artifactVersion.$artifact',
+      ),
+    );
+  }
+  return localEngineRepo;
+}

packages/flutter_tools/test/general.shard/android/gradle_test.dart

@@ -1484,7 +1484,7 @@ plugin2=${plugin2.path}
         ),
         target: 'lib/main.dart',
         isBuildingBundle: false,
-        localGradleErrors: <GradleHandledError>[],
+        localGradleErrors: const <GradleHandledError>[],
       );
 
       final BufferLogger logger = context.get<Logger>();
@@ -1564,6 +1564,96 @@ Consuming the Module
 
 To learn more, visit https://flutter.dev/go/build-aar'''));
 
+    }, overrides: <Type, Generator>{
+      AndroidSdk: () => mockAndroidSdk,
+      AndroidStudio: () => mockAndroidStudio,
+      Cache: () => cache,
+      Platform: () => android,
+      FileSystem: () => fs,
+      ProcessManager: () => mockProcessManager,
+    });
+
+    testUsingContext('build apk uses selected local engine', () async {
+      when(mockArtifacts.getArtifactPath(Artifact.flutterFramework,
+          platform: TargetPlatform.android_arm, mode: anyNamed('mode'))).thenReturn('engine');
+      when(mockArtifacts.engineOutPath).thenReturn(fs.path.join('out', 'android_arm'));
+
+      fs.file('out/android_arm/flutter_embedding_release.pom')
+        ..createSync(recursive: true)
+        ..writeAsStringSync(
+'''<?xml version="1.0" encoding="UTF-8"?>
+<project>
+  <version>1.0.0-73fd6b049a80bcea2db1f26c7cee434907cd188b</version>
+  <dependencies>
+  </dependencies>
+</project>
+''');
+      fs.file('out/android_arm/armeabi_v7a_release.pom').createSync(recursive: true);
+      fs.file('out/android_arm/armeabi_v7a_release.jar').createSync(recursive: true);
+      fs.file('out/android_arm/flutter_embedding_release.jar').createSync(recursive: true);
+      fs.file('out/android_arm/flutter_embedding_release.pom').createSync(recursive: true);
+
+      fs.file('android/gradlew').createSync(recursive: true);
+
+      fs.directory('android')
+        .childFile('gradle.properties')
+        .createSync(recursive: true);
+
+      fs.file('android/build.gradle')
+        .createSync(recursive: true);
+
+      fs.directory('android')
+        .childDirectory('app')
+        .childFile('build.gradle')
+        ..createSync(recursive: true)
+        ..writeAsStringSync('apply from: irrelevant/flutter.gradle');
+
+      // Let any process start. Assert after.
+      when(mockProcessManager.run(
+        any,
+        environment: anyNamed('environment'),
+        workingDirectory: anyNamed('workingDirectory'),
+      )).thenAnswer((_) async => ProcessResult(1, 0, '', ''));
+
+      when(mockProcessManager.start(any,
+        workingDirectory: anyNamed('workingDirectory'),
+        environment: anyNamed('environment')))
+      .thenAnswer((_) {
+        return Future<Process>.value(
+          createMockProcess(
+            exitCode: 1,
+          )
+        );
+      });
+
+      await expectLater(() async {
+        await buildGradleApp(
+          project: FlutterProject.current(),
+          androidBuildInfo: const AndroidBuildInfo(
+            BuildInfo(
+              BuildMode.release,
+              null,
+            ),
+          ),
+          target: 'lib/main.dart',
+          isBuildingBundle: false,
+          localGradleErrors: const <GradleHandledError>[],
+        );
+      }, throwsToolExit());
+
+      final List<String> actualGradlewCall = verify(
+        mockProcessManager.start(
+          captureAny,
+          environment: anyNamed('environment'),
+          workingDirectory: anyNamed('workingDirectory')
+        ),
+      ).captured.last;
+
+      expect(actualGradlewCall, contains('/android/gradlew'));
+      expect(actualGradlewCall, contains('-Plocal-engine-out=out/android_arm'));
+      expect(actualGradlewCall, contains('-Plocal-engine-repo=/.tmp_rand0/flutter_tool_local_engine_repo.rand0'));
+      expect(actualGradlewCall, contains('-Plocal-engine-build-mode=release'));
+
     }, overrides: <Type, Generator>{
       AndroidSdk: () => mockAndroidSdk,
       AndroidStudio: () => mockAndroidStudio,
@@ -1579,6 +1669,21 @@ To learn more, visit https://flutter.dev/go/build-aar'''));
           platform: TargetPlatform.android_arm, mode: anyNamed('mode'))).thenReturn('engine');
       when(mockArtifacts.engineOutPath).thenReturn(fs.path.join('out', 'android_arm'));
 
+      fs.file('out/android_arm/flutter_embedding_release.pom')
+        ..createSync(recursive: true)
+        ..writeAsStringSync(
+'''<?xml version="1.0" encoding="UTF-8"?>
+<project>
+  <version>1.0.0-73fd6b049a80bcea2db1f26c7cee434907cd188b</version>
+  <dependencies>
+  </dependencies>
+</project>
+''');
+      fs.file('out/android_arm/armeabi_v7a_release.pom').createSync(recursive: true);
+      fs.file('out/android_arm/armeabi_v7a_release.jar').createSync(recursive: true);
+      fs.file('out/android_arm/flutter_embedding_release.jar').createSync(recursive: true);
+      fs.file('out/android_arm/flutter_embedding_release.pom').createSync(recursive: true);
+
       final File manifestFile = fs.file('pubspec.yaml');
       manifestFile.createSync(recursive: true);
       manifestFile.writeAsStringSync('''
@@ -1588,8 +1693,7 @@ To learn more, visit https://flutter.dev/go/build-aar'''));
         '''
       );
 
-      final File gradlew = fs.file('.android/gradlew');
-      gradlew.createSync(recursive: true);
+      fs.file('.android/gradlew').createSync(recursive: true);
 
       fs.file('.android/gradle.properties')
         .writeAsStringSync('irrelevant');
@@ -1597,12 +1701,6 @@ To learn more, visit https://flutter.dev/go/build-aar'''));
       fs.file('.android/build.gradle')
         .createSync(recursive: true);
 
-      when(mockProcessManager.run(
-          <String> ['.android/gradlew', '-v'],
-          workingDirectory: anyNamed('workingDirectory'),
-          environment: anyNamed('environment'),
-      )).thenAnswer((_) async => ProcessResult(1, 0, '5.1.1', ''));
-
       // Let any process start. Assert after.
       when(mockProcessManager.run(
         any,
@@ -1619,14 +1717,19 @@ To learn more, visit https://flutter.dev/go/build-aar'''));
         target: '',
       );
 
-      final List<String> actualGradlewCall = verify(mockProcessManager.run(
+      final List<String> actualGradlewCall = verify(
+        mockProcessManager.run(
           captureAny,
           environment: anyNamed('environment'),
-        workingDirectory: anyNamed('workingDirectory')),
+          workingDirectory: anyNamed('workingDirectory'),
+        ),
       ).captured.last;
 
       expect(actualGradlewCall, contains('/.android/gradlew'));
-      expect(actualGradlewCall, contains('-PlocalEngineOut=out/android_arm'));
+      expect(actualGradlewCall, contains('-Plocal-engine-out=out/android_arm'));
+      expect(actualGradlewCall, contains('-Plocal-engine-repo=/.tmp_rand0/flutter_tool_local_engine_repo.rand0'));
+      expect(actualGradlewCall, contains('-Plocal-engine-build-mode=release'));
+
     }, overrides: <Type, Generator>{
       AndroidSdk: () => mockAndroidSdk,
       AndroidStudio: () => mockAndroidStudio,
@@ -1661,7 +1764,9 @@ FlutterProject generateFakeAppBundle(String directoryName, String fileName) {
 }
 
 Platform fakePlatform(String name) {
-  return FakePlatform.fromPlatform(const LocalPlatform())..operatingSystem = name;
+  return FakePlatform.fromPlatform(const LocalPlatform())
+    ..operatingSystem = name
+    ..stdoutSupportsAnsi = false;
 }
 
 class FakeGradleUtils extends GradleUtils {