Add emulator.getEmulators and emulator.launch to daemon (#17466)

Related to:

#14822
Dart-Code/Dart-Code#490
#13379

packages/flutter_tools/lib/src/commands/daemon.dart

@@ -17,6 +17,7 @@ import '../base/utils.dart';
 import '../build_info.dart';
 import '../cache.dart';
 import '../device.dart';
+import '../emulator.dart';
 import '../globals.dart';
 import '../ios/devices.dart';
 import '../ios/simulators.dart';
@@ -88,6 +89,7 @@ class Daemon {
     _registerDomain(daemonDomain = new DaemonDomain(this));
     _registerDomain(appDomain = new AppDomain(this));
     _registerDomain(deviceDomain = new DeviceDomain(this));
+    _registerDomain(emulatorDomain = new EmulatorDomain(this));
 
     // Start listening.
     _commandSubscription = commandStream.listen(
@@ -102,6 +104,7 @@ class Daemon {
   DaemonDomain daemonDomain;
   AppDomain appDomain;
   DeviceDomain deviceDomain;
+  EmulatorDomain emulatorDomain;
   StreamSubscription<Map<String, dynamic>> _commandSubscription;
 
   final DispatchCommand sendCommand;
@@ -729,6 +732,13 @@ Future<Map<String, dynamic>> _deviceToMap(Device device) async {
   };
 }
 
+Map<String, dynamic> _emulatorToMap(Emulator emulator) {
+  return <String, dynamic>{
+    'id': emulator.id,
+    'name': emulator.name,
+  };
+}
+
 Map<String, dynamic> _operationResultToMap(OperationResult result) {
   final Map<String, dynamic> map = <String, dynamic>{
     'code': result.code,
@@ -824,6 +834,34 @@ class AppInstance {
   }
 }
 
+/// This domain responds to methods like [getEmulators] and [launch].
+class EmulatorDomain extends Domain {
+  EmulatorManager emulators = new EmulatorManager();
+
+  EmulatorDomain(Daemon daemon) : super(daemon, 'emulator') {
+    registerHandler('getEmulators', getEmulators);
+    registerHandler('launch', launch);
+  }
+
+  Future<List<Map<String, dynamic>>> getEmulators([Map<String, dynamic> args]) async {
+    final List<Emulator> list = await emulators.getAllAvailableEmulators();
+    return list.map(_emulatorToMap).toList();
+  }
+
+  Future<Null> launch(Map<String, dynamic> args) async {
+    final String emulatorId = _getStringArg(args, 'emulatorId', required: true);
+    final List<Emulator> matches =
+        await emulators.getEmulatorsMatching(emulatorId);
+    if (matches.isEmpty) {
+      throw "emulator '$emulatorId' not found";
+    } else if (matches.length > 1) {
+      throw "multiple emulators match '$emulatorId'";
+    } else {
+      await matches.first.launch();
+    }
+  }
+}
+
 /// A [Logger] which sends log messages to a listening daemon client.
 ///
 /// This class can either:

packages/flutter_tools/test/commands/daemon_test.dart

@@ -263,6 +263,43 @@ void main() {
       AndroidWorkflow: () => new MockAndroidWorkflow(),
       IOSWorkflow: () => new MockIOSWorkflow(),
     });
+
+    testUsingContext('emulator.launch without an emulatorId should report an error', () async {
+      final DaemonCommand command = new DaemonCommand();
+      applyMocksToCommand(command);
+
+      final StreamController<Map<String, dynamic>> commands = new StreamController<Map<String, dynamic>>();
+      final StreamController<Map<String, dynamic>> responses = new StreamController<Map<String, dynamic>>();
+      daemon = new Daemon(
+        commands.stream,
+        responses.add,
+        daemonCommand: command,
+        notifyingLogger: notifyingLogger
+      );
+
+      commands.add(<String, dynamic>{ 'id': 0, 'method': 'emulator.launch' });
+      final Map<String, dynamic> response = await responses.stream.firstWhere(_notEvent);
+      expect(response['id'], 0);
+      expect(response['error'], contains('emulatorId is required'));
+      responses.close();
+      commands.close();
+    });
+
+    testUsingContext('emulator.getEmulators should respond with list', () async {
+      final StreamController<Map<String, dynamic>> commands = new StreamController<Map<String, dynamic>>();
+      final StreamController<Map<String, dynamic>> responses = new StreamController<Map<String, dynamic>>();
+      daemon = new Daemon(
+        commands.stream,
+        responses.add,
+        notifyingLogger: notifyingLogger
+      );
+      commands.add(<String, dynamic>{'id': 0, 'method': 'emulator.getEmulators'});
+      final Map<String, dynamic> response = await responses.stream.firstWhere(_notEvent);
+      expect(response['id'], 0);
+      expect(response['result'], isList);
+      responses.close();
+      commands.close();
+    });
   });
 
   group('daemon serialization', () {

packages/flutter_tools/tool/daemon_client.dart

@@ -5,7 +5,7 @@
 import 'dart:async';
 import 'dart:convert';
 
-import 'package:flutter_tools/src/base/io.dart';
+import 'dart:io';
 
 Process daemon;
 
@@ -15,6 +15,8 @@ Process daemon;
 //   start: start an app
 //   stop: stop a running app
 //   devices: list devices
+//   emulators: list emulators
+//   launch: launch an emulator
 
 Future<Null> main() async {
   daemon = await Process.start('dart', <String>['bin/flutter_tools.dart', 'daemon']);
@@ -62,6 +64,15 @@ Future<Null> main() async {
       }
     } else if (line == 'devices') {
       _send(<String, dynamic>{'method': 'device.getDevices'});
+    } else if (line == 'emulators') {
+      _send(<String, dynamic>{'method': 'emulator.getEmulators'});
+    } else if (words.first == 'emulator-launch') {
+      _send(<String, dynamic>{
+        'method': 'emulator.launch',
+        'params': <String, dynamic>{
+          'emulatorId': words[1]
+        }
+      });
     } else if (line == 'enable') {
       _send(<String, dynamic>{'method': 'device.enable'});
     } else {