packages/flutter_tools/lib/src/fuchsia/fuchsia_device.dart - mirrors/flutter - Git at Google

 // Copyright 2017 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.

 import 'dart:async';

 import 'package:meta/meta.dart';

 import '../application_package.dart';
 import '../artifacts.dart';
 import '../base/common.dart';
 import '../base/context.dart';
 import '../base/file_system.dart';
 import '../base/io.dart';
 import '../base/logger.dart';
 import '../base/os.dart';
 import '../base/platform.dart';
 import '../base/process.dart';
 import '../base/process_manager.dart';
 import '../base/time.dart';
 import '../build_info.dart';
 import '../device.dart';
 import '../globals.dart';
 import '../project.dart';
 import '../vmservice.dart';

 import 'amber_ctl.dart';
 import 'application_package.dart';
 import 'fuchsia_build.dart';
 import 'fuchsia_pm.dart';
 import 'fuchsia_sdk.dart';
 import 'fuchsia_workflow.dart';
 import 'tiles_ctl.dart';

 /// The [FuchsiaDeviceTools] instance.
 FuchsiaDeviceTools get fuchsiaDeviceTools => context.get<FuchsiaDeviceTools>();

 /// Fuchsia device-side tools.
 class FuchsiaDeviceTools {
   FuchsiaAmberCtl _amberCtl;
   FuchsiaAmberCtl get amberCtl => _amberCtl ??= FuchsiaAmberCtl();

   FuchsiaTilesCtl _tilesCtl;
   FuchsiaTilesCtl get tilesCtl => _tilesCtl ??= FuchsiaTilesCtl();
 }

 final String _ipv4Loopback = InternetAddress.loopbackIPv4.address;
 final String _ipv6Loopback = InternetAddress.loopbackIPv6.address;

 // Enables testing the fuchsia isolate discovery
 Future<VMService> _kDefaultFuchsiaIsolateDiscoveryConnector(Uri uri) {
   return VMService.connect(uri);
 }

 /// Read the log for a particular device.
 class _FuchsiaLogReader extends DeviceLogReader {
   _FuchsiaLogReader(this._device, [this._app]);

   // \S matches non-whitespace characters.
   static final RegExp _flutterLogOutput = RegExp(r'INFO: \S+\(flutter\): ');

   FuchsiaDevice _device;
   ApplicationPackage _app;

   @override
   String get name => _device.name;

   Stream<String> _logLines;
   @override
   Stream<String> get logLines {
     final Stream<String> logStream = fuchsiaSdk.syslogs(_device.id);
     _logLines ??= _processLogs(logStream);
     return _logLines;
   }

   Stream<String> _processLogs(Stream<String> lines) {
     if (lines == null) {
       return null;
     }
     // Get the starting time of the log processor to filter logs from before
     // the process attached.
     final DateTime startTime = systemClock.now();
     // Determine if line comes from flutter, and optionally whether it matches
     // the correct fuchsia module.
     final RegExp matchRegExp = _app == null
         ? _flutterLogOutput
         : RegExp('INFO: ${_app.name}(\.cmx)?\\(flutter\\): ');
     return Stream<String>.eventTransformed(
       lines,
       (Sink<String> outout) => _FuchsiaLogSink(outout, matchRegExp, startTime),
     );
   }

   @override
   String toString() => name;
 }

 class _FuchsiaLogSink implements EventSink<String> {
   _FuchsiaLogSink(this._outputSink, this._matchRegExp, this._startTime);

   static final RegExp _utcDateOutput = RegExp(r'\d+\-\d+\-\d+ \d+:\d+:\d+');
   final EventSink<String> _outputSink;
   final RegExp _matchRegExp;
   final DateTime _startTime;

   @override
   void add(String line) {
     if (!_matchRegExp.hasMatch(line)) {
       return;
     }
     final String rawDate = _utcDateOutput.firstMatch(line)?.group(0);
     if (rawDate == null) {
       return;
     }
     final DateTime logTime = DateTime.parse(rawDate);
     if (logTime.millisecondsSinceEpoch < _startTime.millisecondsSinceEpoch) {
       return;
     }
     _outputSink.add(
         '[${logTime.toLocal()}] Flutter: ${line.split(_matchRegExp).last}');
   }

   @override
   void addError(Object error, [StackTrace stackTrace]) {
     _outputSink.addError(error, stackTrace);
   }

   @override
   void close() {
     _outputSink.close();
   }
 }

 class FuchsiaDevices extends PollingDeviceDiscovery {
   FuchsiaDevices() : super('Fuchsia devices');

   @override
   bool get supportsPlatform => platform.isLinux || platform.isMacOS;

   @override
   bool get canListAnything => fuchsiaWorkflow.canListDevices;

   @override
   Future<List<Device>> pollingGetDevices() async {
     if (!fuchsiaWorkflow.canListDevices) {
       return <Device>[];
     }
     final String text = await fuchsiaSdk.listDevices();
     if (text == null || text.isEmpty) {
       return <Device>[];
     }
     final List<FuchsiaDevice> devices = parseListDevices(text);
     return devices;
   }

   @override
   Future<List<String>> getDiagnostics() async => const <String>[];
 }

 @visibleForTesting
 List<FuchsiaDevice> parseListDevices(String text) {
   final List<FuchsiaDevice> devices = <FuchsiaDevice>[];
   for (String rawLine in text.trim().split('\n')) {
     final String line = rawLine.trim();
     // ['ip', 'device name']
     final List<String> words = line.split(' ');
     if (words.length < 2) {
       continue;
     }
     final String name = words[1];
     final String id = words[0];
     devices.add(FuchsiaDevice(id, name: name));
   }
   return devices;
 }

 class FuchsiaDevice extends Device {
   FuchsiaDevice(String id, {this.name}) : super(id);

   @override
   bool get supportsHotReload => true;

   @override
   bool get supportsHotRestart => false;

   @override
   bool get supportsFlutterExit => false;

   @override
   final String name;

   @override
   Future<bool> get isLocalEmulator async => false;

   @override
   bool get supportsStartPaused => false;

   @override
   Future<bool> isAppInstalled(ApplicationPackage app) async => false;

   @override
   Future<bool> isLatestBuildInstalled(ApplicationPackage app) async => false;

   @override
   Future<bool> installApp(ApplicationPackage app) => Future<bool>.value(false);

   @override
   Future<bool> uninstallApp(ApplicationPackage app) async => false;

   @override
   bool isSupported() => true;

   @override
   Future<LaunchResult> startApp(
     covariant FuchsiaApp package, {
     String mainPath,
     String route,
     DebuggingOptions debuggingOptions,
     Map<String, dynamic> platformArgs,
     bool prebuiltApplication = false,
     bool usesTerminalUi = true,
     bool ipv6 = false,
   }) async {
     if (!prebuiltApplication) {
       await buildFuchsia(fuchsiaProject: FlutterProject.current().fuchsia,
                          target: mainPath,
                          buildInfo: debuggingOptions.buildInfo);
     }
     // Stop the app if it's currently running.
     await stopApp(package);
     // Find out who the device thinks we are.
     final String host = await fuchsiaSdk.fuchsiaDevFinder.resolve(name);
     if (host == null) {
       printError('Failed to resolve host for Fuchsia device');
       return LaunchResult.failed();
     }
     final int port = await os.findFreePort();
     if (port == 0) {
       printError('Failed to find a free port');
       return LaunchResult.failed();
     }
     final Directory packageRepo =
         fs.directory(fs.path.join(getFuchsiaBuildDirectory(), '.pkg-repo'));
     packageRepo.createSync(recursive: true);

     final String appName = FlutterProject.current().manifest.appName;

     final Status status = logger.startProgress(
       'Starting Fuchsia application...',
       timeout: null,
     );
     FuchsiaPackageServer fuchsiaPackageServer;
     bool serverRegistered = false;
     try {
       // Ask amber to pre-fetch some things we'll need before setting up our own
       // package server. This is to avoid relying on amber correctly using
       // multiple package servers, support for which is in flux.
       if (!await fuchsiaDeviceTools.amberCtl.getUp(this, 'tiles')) {
         printError('Failed to get amber to prefetch tiles');
         return LaunchResult.failed();
       }
       if (!await fuchsiaDeviceTools.amberCtl.getUp(this, 'tiles_ctl')) {
         printError('Failed to get amber to prefetch tiles_ctl');
         return LaunchResult.failed();
       }

       // Start up a package server.
       const String packageServerName = 'flutter_tool';
       fuchsiaPackageServer = FuchsiaPackageServer(
           packageRepo.path, packageServerName, host, port);
       if (!await fuchsiaPackageServer.start()) {
         printError('Failed to start the Fuchsia package server');
         return LaunchResult.failed();
       }
       final File farArchive = package.farArchive(
           debuggingOptions.buildInfo.mode);
       if (!await fuchsiaPackageServer.addPackage(farArchive)) {
         printError('Failed to add package to the package server');
         return LaunchResult.failed();
       }

       // Teach the package controller about the package server.
       if (!await fuchsiaDeviceTools.amberCtl.addRepoCfg(this, fuchsiaPackageServer)) {
         printError('Failed to teach amber about the package server');
         return LaunchResult.failed();
       }
       serverRegistered = true;

       // Tell the package controller to prefetch the app.
       if (!await fuchsiaDeviceTools.amberCtl.pkgCtlResolve(
           this, fuchsiaPackageServer, appName)) {
         printError('Failed to get pkgctl to prefetch the package');
         return LaunchResult.failed();
       }

       // Ensure tiles_ctl is started, and start the app.
       if (!await FuchsiaTilesCtl.ensureStarted(this)) {
         printError('Failed to ensure that tiles is started on the device');
         return LaunchResult.failed();
       }

       // Instruct tiles_ctl to start the app.
       final String fuchsiaUrl =
           'fuchsia-pkg://$packageServerName/$appName#meta/$appName.cmx';
       if (!await fuchsiaDeviceTools.tilesCtl.add(this, fuchsiaUrl, <String>[])) {
         printError('Failed to add the app to tiles');
         return LaunchResult.failed();
       }
     } finally {
       // Try to un-teach the package controller about the package server if
       // needed.
       if (serverRegistered) {
         await fuchsiaDeviceTools.amberCtl.pkgCtlRepoRemove(this, fuchsiaPackageServer);
       }
       // Shutdown the package server and delete the package repo;
       fuchsiaPackageServer?.stop();
       packageRepo.deleteSync(recursive: true);
       status.cancel();
     }

     if (!debuggingOptions.buildInfo.isDebug &&
         !debuggingOptions.buildInfo.isProfile) {
       return LaunchResult.succeeded();
     }

     // In a debug or profile build, try to find the observatory uri.
     final FuchsiaIsolateDiscoveryProtocol discovery =
         getIsolateDiscoveryProtocol(appName);
     try {
       final Uri observatoryUri = await discovery.uri;
       return LaunchResult.succeeded(observatoryUri: observatoryUri);
     } finally {
       discovery.dispose();
     }
   }

   @override
   Future<bool> stopApp(covariant FuchsiaApp app) async {
     final int appKey = await FuchsiaTilesCtl.findAppKey(this, app.id);
     if (appKey != -1) {
       if (!await fuchsiaDeviceTools.tilesCtl.remove(this, appKey)) {
         printError('tiles_ctl remove on ${app.id} failed.');
         return false;
       }
     }
     return true;
   }

   @override
   Future<TargetPlatform> get targetPlatform async => TargetPlatform.fuchsia;

   @override
   Future<String> get sdkNameAndVersion async => 'Fuchsia';

   @override
   DeviceLogReader getLogReader({ApplicationPackage app}) =>
       _logReader ??= _FuchsiaLogReader(this, app);
   _FuchsiaLogReader _logReader;

   @override
   DevicePortForwarder get portForwarder =>
       _portForwarder ??= _FuchsiaPortForwarder(this);
   _FuchsiaPortForwarder _portForwarder;

   @override
   void clearLogs() {}

   @override
   OverrideArtifacts get artifactOverrides {
     return _artifactOverrides ??= OverrideArtifacts(
       parent: Artifacts.instance,
       platformKernelDill: fuchsiaArtifacts.platformKernelDill,
       flutterPatchedSdk: fuchsiaArtifacts.flutterPatchedSdk,
     );
   }
   OverrideArtifacts _artifactOverrides;

   @override
   bool get supportsScreenshot => false;

   bool get ipv6 {
     // Workaround for https://github.com/dart-lang/sdk/issues/29456
     final String fragment = id.split('%').first;
     try {
       Uri.parseIPv6Address(fragment);
       return true;
     } on FormatException {
       return false;
     }
   }

   /// List the ports currently running a dart observatory.
   Future<List<int>> servicePorts() async {
     const String findCommand = 'find /hub -name vmservice-port';
     final RunResult findResult = await shell(findCommand);
     if (findResult.exitCode != 0) {
       throwToolExit("'$findCommand' on device $id failed. stderr: '${findResult.stderr}'");
       return null;
     }
     final String findOutput = findResult.stdout;
     if (findOutput.trim() == '') {
       throwToolExit(
           'No Dart Observatories found. Are you running a debug build?');
       return null;
     }
     final List<int> ports = <int>[];
     for (String path in findOutput.split('\n')) {
       if (path == '') {
         continue;
       }
       final String lsCommand = 'ls $path';
       final RunResult lsResult = await shell(lsCommand);
       if (lsResult.exitCode != 0) {
         throwToolExit("'$lsCommand' on device $id failed");
         return null;
       }
       final String lsOutput = lsResult.stdout;
       for (String line in lsOutput.split('\n')) {
         if (line == '') {
           continue;
         }
         final int port = int.tryParse(line);
         if (port != null) {
           ports.add(port);
         }
       }
     }
     return ports;
   }

   /// Run `command` on the Fuchsia device shell.
   Future<RunResult> shell(String command) async {
     if (fuchsiaArtifacts.sshConfig == null) {
       throwToolExit('Cannot interact with device. No ssh config.\n'
                     'Try setting FUCHSIA_SSH_CONFIG or FUCHSIA_BUILD_DIR.');
     }
     return await runAsync(<String>[
       'ssh',
       '-F',
       fuchsiaArtifacts.sshConfig.absolute.path,
       id,
       command
     ]);
   }

   /// Finds the first port running a VM matching `isolateName` from the
   /// provided set of `ports`.
   ///
   /// Returns null if no isolate port can be found.
   ///
   // TODO(jonahwilliams): replacing this with the hub will require an update
   // to the flutter_runner.
   Future<int> findIsolatePort(String isolateName, List<int> ports) async {
     for (int port in ports) {
       try {
         // Note: The square-bracket enclosure for using the IPv6 loopback
         // didn't appear to work, but when assigning to the IPv4 loopback device,
         // netstat shows that the local port is actually being used on the IPv6
         // loopback (::1).
         final Uri uri = Uri.parse('http://[$_ipv6Loopback]:$port');
         final VMService vmService = await VMService.connect(uri);
         await vmService.getVM();
         await vmService.refreshViews();
         for (FlutterView flutterView in vmService.vm.views) {
           if (flutterView.uiIsolate == null) {
             continue;
           }
           final Uri address = flutterView.owner.vmService.httpAddress;
           if (flutterView.uiIsolate.name.contains(isolateName)) {
             return address.port;
           }
         }
       } on SocketException catch (err) {
         printTrace('Failed to connect to $port: $err');
       }
     }
     throwToolExit('No ports found running $isolateName');
     return null;
   }

   FuchsiaIsolateDiscoveryProtocol getIsolateDiscoveryProtocol(
           String isolateName) =>
       FuchsiaIsolateDiscoveryProtocol(this, isolateName);

   @override
   bool isSupportedForProject(FlutterProject flutterProject) {
     return flutterProject.fuchsia.existsSync();
   }
 }

 class FuchsiaIsolateDiscoveryProtocol {
   FuchsiaIsolateDiscoveryProtocol(
     this._device,
     this._isolateName, [
     this._vmServiceConnector = _kDefaultFuchsiaIsolateDiscoveryConnector,
     this._pollOnce = false,
   ]);

   static const Duration _pollDuration = Duration(seconds: 10);
   final Map<int, VMService> _ports = <int, VMService>{};
   final FuchsiaDevice _device;
   final String _isolateName;
   final Completer<Uri> _foundUri = Completer<Uri>();
   final Future<VMService> Function(Uri) _vmServiceConnector;
   // whether to only poll once.
   final bool _pollOnce;
   Timer _pollingTimer;
   Status _status;

   FutureOr<Uri> get uri {
     if (_uri != null) {
       return _uri;
     }
     _status ??= logger.startProgress(
       'Waiting for a connection from $_isolateName on ${_device.name}...',
       timeout: null, // could take an arbitrary amount of time
     );
     _pollingTimer ??= Timer(_pollDuration, _findIsolate);
     return _foundUri.future.then((Uri uri) {
       _uri = uri;
       return uri;
     });
   }

   Uri _uri;

   void dispose() {
     if (!_foundUri.isCompleted) {
       _status?.cancel();
       _status = null;
       _pollingTimer?.cancel();
       _pollingTimer = null;
       _foundUri.completeError(Exception('Did not complete'));
     }
   }

   Future<void> _findIsolate() async {
     final List<int> ports = await _device.servicePorts();
     for (int port in ports) {
       VMService service;
       if (_ports.containsKey(port)) {
         service = _ports[port];
       } else {
         final int localPort = await _device.portForwarder.forward(port);
         try {
           final Uri uri = Uri.parse('http://[$_ipv6Loopback]:$localPort');
           service = await _vmServiceConnector(uri);
           _ports[port] = service;
         } on SocketException catch (err) {
           printTrace('Failed to connect to $localPort: $err');
           continue;
         }
       }
       await service.getVM();
       await service.refreshViews();
       for (FlutterView flutterView in service.vm.views) {
         if (flutterView.uiIsolate == null) {
           continue;
         }
         final Uri address = flutterView.owner.vmService.httpAddress;
         if (flutterView.uiIsolate.name.contains(_isolateName)) {
           _foundUri.complete(_device.ipv6
               ? Uri.parse('http://[$_ipv6Loopback]:${address.port}/')
               : Uri.parse('http://$_ipv4Loopback:${address.port}/'));
           _status.stop();
           return;
         }
       }
     }
     if (_pollOnce) {
       _foundUri.completeError(Exception('Max iterations exceeded'));
       _status.stop();
       return;
     }
     _pollingTimer = Timer(_pollDuration, _findIsolate);
   }
 }

 class _FuchsiaPortForwarder extends DevicePortForwarder {
   _FuchsiaPortForwarder(this.device);

   final FuchsiaDevice device;
   final Map<int, Process> _processes = <int, Process>{};

   @override
   Future<int> forward(int devicePort, {int hostPort}) async {
     hostPort ??= await os.findFreePort();
     if (hostPort == 0) {
       throwToolExit('Failed to forward port $devicePort. No free host-side ports');
     }
     // Note: the provided command works around a bug in -N, see US-515
     // for more explanation.
     final List<String> command = <String>[
       'ssh',
       '-6',
       '-F',
       fuchsiaArtifacts.sshConfig.absolute.path,
       '-nNT',
       '-vvv',
       '-f',
       '-L',
       '$hostPort:$_ipv4Loopback:$devicePort',
       device.id,
       'true',
     ];
     final Process process = await processManager.start(command);
     unawaited(process.exitCode.then((int exitCode) {
       if (exitCode != 0) {
         throwToolExit('Failed to forward port:$devicePort');
       }
     }));
     _processes[hostPort] = process;
     _forwardedPorts.add(ForwardedPort(hostPort, devicePort));
     return hostPort;
   }

   @override
   List<ForwardedPort> get forwardedPorts => _forwardedPorts;
   final List<ForwardedPort> _forwardedPorts = <ForwardedPort>[];

   @override
   Future<void> unforward(ForwardedPort forwardedPort) async {
     _forwardedPorts.remove(forwardedPort);
     final Process process = _processes.remove(forwardedPort.hostPort);
     process?.kill();
     final List<String> command = <String>[
       'ssh',
       '-F',
       fuchsiaArtifacts.sshConfig.absolute.path,
       '-O',
       'cancel',
       '-vvv',
       '-L',
       '${forwardedPort.hostPort}:$_ipv4Loopback:${forwardedPort.devicePort}',
       device.id
     ];
     final ProcessResult result = await processManager.run(command);
     if (result.exitCode != 0) {
       throwToolExit(result.stderr);
     }
   }
 }
	// Copyright 2017 The Chromium Authors. All rights reserved.
	// Use of this source code is governed by a BSD-style license that can be
	// found in the LICENSE file.

	import 'dart:async';

	import 'package:meta/meta.dart';

	import '../application_package.dart';
	import '../artifacts.dart';
	import '../base/common.dart';
	import '../base/context.dart';
	import '../base/file_system.dart';
	import '../base/io.dart';
	import '../base/logger.dart';
	import '../base/os.dart';
	import '../base/platform.dart';
	import '../base/process.dart';
	import '../base/process_manager.dart';
	import '../base/time.dart';
	import '../build_info.dart';
	import '../device.dart';
	import '../globals.dart';
	import '../project.dart';
	import '../vmservice.dart';

	import 'amber_ctl.dart';
	import 'application_package.dart';
	import 'fuchsia_build.dart';
	import 'fuchsia_pm.dart';
	import 'fuchsia_sdk.dart';
	import 'fuchsia_workflow.dart';
	import 'tiles_ctl.dart';

	/// The [FuchsiaDeviceTools] instance.
	FuchsiaDeviceTools get fuchsiaDeviceTools => context.get<FuchsiaDeviceTools>();

	/// Fuchsia device-side tools.
	class FuchsiaDeviceTools {
	FuchsiaAmberCtl _amberCtl;
	FuchsiaAmberCtl get amberCtl => _amberCtl ??= FuchsiaAmberCtl();

	FuchsiaTilesCtl _tilesCtl;
	FuchsiaTilesCtl get tilesCtl => _tilesCtl ??= FuchsiaTilesCtl();
	}

	final String _ipv4Loopback = InternetAddress.loopbackIPv4.address;
	final String _ipv6Loopback = InternetAddress.loopbackIPv6.address;

	// Enables testing the fuchsia isolate discovery
	Future<VMService> _kDefaultFuchsiaIsolateDiscoveryConnector(Uri uri) {
	return VMService.connect(uri);
	}

	/// Read the log for a particular device.
	class _FuchsiaLogReader extends DeviceLogReader {
	_FuchsiaLogReader(this._device, [this._app]);

	// \S matches non-whitespace characters.
	static final RegExp _flutterLogOutput = RegExp(r'INFO: \S+\(flutter\): ');

	FuchsiaDevice _device;
	ApplicationPackage _app;

	@override
	String get name => _device.name;

	Stream<String> _logLines;
	@override
	Stream<String> get logLines {
	final Stream<String> logStream = fuchsiaSdk.syslogs(_device.id);
	_logLines ??= _processLogs(logStream);
	return _logLines;
	}

	Stream<String> _processLogs(Stream<String> lines) {
	if (lines == null) {
	return null;
	}
	// Get the starting time of the log processor to filter logs from before
	// the process attached.
	final DateTime startTime = systemClock.now();
	// Determine if line comes from flutter, and optionally whether it matches
	// the correct fuchsia module.
	final RegExp matchRegExp = _app == null
	? _flutterLogOutput
	: RegExp('INFO: ${_app.name}(\.cmx)?\\(flutter\\): ');
	return Stream<String>.eventTransformed(
	lines,
	(Sink<String> outout) => _FuchsiaLogSink(outout, matchRegExp, startTime),
	);
	}

	@override
	String toString() => name;
	}

	class _FuchsiaLogSink implements EventSink<String> {
	_FuchsiaLogSink(this._outputSink, this._matchRegExp, this._startTime);

	static final RegExp _utcDateOutput = RegExp(r'\d+\-\d+\-\d+ \d+:\d+:\d+');
	final EventSink<String> _outputSink;
	final RegExp _matchRegExp;
	final DateTime _startTime;

	@override
	void add(String line) {
	if (!_matchRegExp.hasMatch(line)) {
	return;
	}
	final String rawDate = _utcDateOutput.firstMatch(line)?.group(0);
	if (rawDate == null) {
	return;
	}
	final DateTime logTime = DateTime.parse(rawDate);
	if (logTime.millisecondsSinceEpoch < _startTime.millisecondsSinceEpoch) {
	return;
	}
	_outputSink.add(
	'[${logTime.toLocal()}] Flutter: ${line.split(_matchRegExp).last}');
	}

	@override
	void addError(Object error, [StackTrace stackTrace]) {
	_outputSink.addError(error, stackTrace);
	}

	@override
	void close() {
	_outputSink.close();
	}
	}

	class FuchsiaDevices extends PollingDeviceDiscovery {
	FuchsiaDevices() : super('Fuchsia devices');

	@override
	bool get supportsPlatform => platform.isLinux \|\| platform.isMacOS;

	@override
	bool get canListAnything => fuchsiaWorkflow.canListDevices;

	@override
	Future<List<Device>> pollingGetDevices() async {
	if (!fuchsiaWorkflow.canListDevices) {
	return <Device>[];
	}
	final String text = await fuchsiaSdk.listDevices();
	if (text == null \|\| text.isEmpty) {
	return <Device>[];
	}
	final List<FuchsiaDevice> devices = parseListDevices(text);
	return devices;
	}

	@override
	Future<List<String>> getDiagnostics() async => const <String>[];
	}

	@visibleForTesting
	List<FuchsiaDevice> parseListDevices(String text) {
	final List<FuchsiaDevice> devices = <FuchsiaDevice>[];
	for (String rawLine in text.trim().split('\n')) {
	final String line = rawLine.trim();
	// ['ip', 'device name']
	final List<String> words = line.split(' ');
	if (words.length < 2) {
	continue;
	}
	final String name = words[1];
	final String id = words[0];
	devices.add(FuchsiaDevice(id, name: name));
	}
	return devices;
	}

	class FuchsiaDevice extends Device {
	FuchsiaDevice(String id, {this.name}) : super(id);

	@override
	bool get supportsHotReload => true;

	@override
	bool get supportsHotRestart => false;

	@override
	bool get supportsFlutterExit => false;

	@override
	final String name;

	@override
	Future<bool> get isLocalEmulator async => false;

	@override
	bool get supportsStartPaused => false;

	@override
	Future<bool> isAppInstalled(ApplicationPackage app) async => false;

	@override
	Future<bool> isLatestBuildInstalled(ApplicationPackage app) async => false;

	@override
	Future<bool> installApp(ApplicationPackage app) => Future<bool>.value(false);

	@override
	Future<bool> uninstallApp(ApplicationPackage app) async => false;

	@override
	bool isSupported() => true;

	@override
	Future<LaunchResult> startApp(
	covariant FuchsiaApp package, {
	String mainPath,
	String route,
	DebuggingOptions debuggingOptions,
	Map<String, dynamic> platformArgs,
	bool prebuiltApplication = false,
	bool usesTerminalUi = true,
	bool ipv6 = false,
	}) async {
	if (!prebuiltApplication) {
	await buildFuchsia(fuchsiaProject: FlutterProject.current().fuchsia,
	target: mainPath,
	buildInfo: debuggingOptions.buildInfo);
	}
	// Stop the app if it's currently running.
	await stopApp(package);
	// Find out who the device thinks we are.
	final String host = await fuchsiaSdk.fuchsiaDevFinder.resolve(name);
	if (host == null) {
	printError('Failed to resolve host for Fuchsia device');
	return LaunchResult.failed();
	}
	final int port = await os.findFreePort();
	if (port == 0) {
	printError('Failed to find a free port');
	return LaunchResult.failed();
	}
	final Directory packageRepo =
	fs.directory(fs.path.join(getFuchsiaBuildDirectory(), '.pkg-repo'));
	packageRepo.createSync(recursive: true);

	final String appName = FlutterProject.current().manifest.appName;

	final Status status = logger.startProgress(
	'Starting Fuchsia application...',
	timeout: null,
	);
	FuchsiaPackageServer fuchsiaPackageServer;
	bool serverRegistered = false;
	try {
	// Ask amber to pre-fetch some things we'll need before setting up our own
	// package server. This is to avoid relying on amber correctly using
	// multiple package servers, support for which is in flux.
	if (!await fuchsiaDeviceTools.amberCtl.getUp(this, 'tiles')) {
	printError('Failed to get amber to prefetch tiles');
	return LaunchResult.failed();
	}
	if (!await fuchsiaDeviceTools.amberCtl.getUp(this, 'tiles_ctl')) {
	printError('Failed to get amber to prefetch tiles_ctl');
	return LaunchResult.failed();
	}

	// Start up a package server.
	const String packageServerName = 'flutter_tool';
	fuchsiaPackageServer = FuchsiaPackageServer(
	packageRepo.path, packageServerName, host, port);
	if (!await fuchsiaPackageServer.start()) {
	printError('Failed to start the Fuchsia package server');
	return LaunchResult.failed();
	}
	final File farArchive = package.farArchive(
	debuggingOptions.buildInfo.mode);
	if (!await fuchsiaPackageServer.addPackage(farArchive)) {
	printError('Failed to add package to the package server');
	return LaunchResult.failed();
	}

	// Teach the package controller about the package server.
	if (!await fuchsiaDeviceTools.amberCtl.addRepoCfg(this, fuchsiaPackageServer)) {
	printError('Failed to teach amber about the package server');
	return LaunchResult.failed();
	}
	serverRegistered = true;

	// Tell the package controller to prefetch the app.
	if (!await fuchsiaDeviceTools.amberCtl.pkgCtlResolve(
	this, fuchsiaPackageServer, appName)) {
	printError('Failed to get pkgctl to prefetch the package');
	return LaunchResult.failed();
	}

	// Ensure tiles_ctl is started, and start the app.
	if (!await FuchsiaTilesCtl.ensureStarted(this)) {
	printError('Failed to ensure that tiles is started on the device');
	return LaunchResult.failed();
	}

	// Instruct tiles_ctl to start the app.
	final String fuchsiaUrl =
	'fuchsia-pkg://$packageServerName/$appName#meta/$appName.cmx';
	if (!await fuchsiaDeviceTools.tilesCtl.add(this, fuchsiaUrl, <String>[])) {
	printError('Failed to add the app to tiles');
	return LaunchResult.failed();
	}
	} finally {
	// Try to un-teach the package controller about the package server if
	// needed.
	if (serverRegistered) {
	await fuchsiaDeviceTools.amberCtl.pkgCtlRepoRemove(this, fuchsiaPackageServer);
	}
	// Shutdown the package server and delete the package repo;
	fuchsiaPackageServer?.stop();
	packageRepo.deleteSync(recursive: true);
	status.cancel();
	}

	if (!debuggingOptions.buildInfo.isDebug &&
	!debuggingOptions.buildInfo.isProfile) {
	return LaunchResult.succeeded();
	}

	// In a debug or profile build, try to find the observatory uri.
	final FuchsiaIsolateDiscoveryProtocol discovery =
	getIsolateDiscoveryProtocol(appName);
	try {
	final Uri observatoryUri = await discovery.uri;
	return LaunchResult.succeeded(observatoryUri: observatoryUri);
	} finally {
	discovery.dispose();
	}
	}

	@override
	Future<bool> stopApp(covariant FuchsiaApp app) async {
	final int appKey = await FuchsiaTilesCtl.findAppKey(this, app.id);
	if (appKey != -1) {
	if (!await fuchsiaDeviceTools.tilesCtl.remove(this, appKey)) {
	printError('tiles_ctl remove on ${app.id} failed.');
	return false;
	}
	}
	return true;
	}

	@override
	Future<TargetPlatform> get targetPlatform async => TargetPlatform.fuchsia;

	@override
	Future<String> get sdkNameAndVersion async => 'Fuchsia';

	@override
	DeviceLogReader getLogReader({ApplicationPackage app}) =>
	_logReader ??= _FuchsiaLogReader(this, app);
	_FuchsiaLogReader _logReader;

	@override
	DevicePortForwarder get portForwarder =>
	_portForwarder ??= _FuchsiaPortForwarder(this);
	_FuchsiaPortForwarder _portForwarder;

	@override
	void clearLogs() {}

	@override
	OverrideArtifacts get artifactOverrides {
	return _artifactOverrides ??= OverrideArtifacts(
	parent: Artifacts.instance,
	platformKernelDill: fuchsiaArtifacts.platformKernelDill,
	flutterPatchedSdk: fuchsiaArtifacts.flutterPatchedSdk,
	);
	}
	OverrideArtifacts _artifactOverrides;

	@override
	bool get supportsScreenshot => false;

	bool get ipv6 {
	// Workaround for https://github.com/dart-lang/sdk/issues/29456
	final String fragment = id.split('%').first;
	try {
	Uri.parseIPv6Address(fragment);
	return true;
	} on FormatException {
	return false;
	}
	}

	/// List the ports currently running a dart observatory.
	Future<List<int>> servicePorts() async {
	const String findCommand = 'find /hub -name vmservice-port';
	final RunResult findResult = await shell(findCommand);
	if (findResult.exitCode != 0) {
	throwToolExit("'$findCommand' on device $id failed. stderr: '${findResult.stderr}'");
	return null;
	}
	final String findOutput = findResult.stdout;
	if (findOutput.trim() == '') {
	throwToolExit(
	'No Dart Observatories found. Are you running a debug build?');
	return null;
	}
	final List<int> ports = <int>[];
	for (String path in findOutput.split('\n')) {
	if (path == '') {
	continue;
	}
	final String lsCommand = 'ls $path';
	final RunResult lsResult = await shell(lsCommand);
	if (lsResult.exitCode != 0) {
	throwToolExit("'$lsCommand' on device $id failed");
	return null;
	}
	final String lsOutput = lsResult.stdout;
	for (String line in lsOutput.split('\n')) {
	if (line == '') {
	continue;
	}
	final int port = int.tryParse(line);
	if (port != null) {
	ports.add(port);
	}
	}
	}
	return ports;
	}

	/// Run `command` on the Fuchsia device shell.
	Future<RunResult> shell(String command) async {
	if (fuchsiaArtifacts.sshConfig == null) {
	throwToolExit('Cannot interact with device. No ssh config.\n'
	'Try setting FUCHSIA_SSH_CONFIG or FUCHSIA_BUILD_DIR.');
	}
	return await runAsync(<String>[
	'ssh',
	'-F',
	fuchsiaArtifacts.sshConfig.absolute.path,
	id,
	command
	]);
	}

	/// Finds the first port running a VM matching `isolateName` from the
	/// provided set of `ports`.
	///
	/// Returns null if no isolate port can be found.
	///
	// TODO(jonahwilliams): replacing this with the hub will require an update
	// to the flutter_runner.
	Future<int> findIsolatePort(String isolateName, List<int> ports) async {
	for (int port in ports) {
	try {
	// Note: The square-bracket enclosure for using the IPv6 loopback
	// didn't appear to work, but when assigning to the IPv4 loopback device,
	// netstat shows that the local port is actually being used on the IPv6
	// loopback (::1).
	final Uri uri = Uri.parse('http://[$_ipv6Loopback]:$port');
	final VMService vmService = await VMService.connect(uri);
	await vmService.getVM();
	await vmService.refreshViews();
	for (FlutterView flutterView in vmService.vm.views) {
	if (flutterView.uiIsolate == null) {
	continue;
	}
	final Uri address = flutterView.owner.vmService.httpAddress;
	if (flutterView.uiIsolate.name.contains(isolateName)) {
	return address.port;
	}
	}
	} on SocketException catch (err) {
	printTrace('Failed to connect to $port: $err');
	}
	}
	throwToolExit('No ports found running $isolateName');
	return null;
	}

	FuchsiaIsolateDiscoveryProtocol getIsolateDiscoveryProtocol(
	String isolateName) =>
	FuchsiaIsolateDiscoveryProtocol(this, isolateName);

	@override
	bool isSupportedForProject(FlutterProject flutterProject) {
	return flutterProject.fuchsia.existsSync();
	}
	}

	class FuchsiaIsolateDiscoveryProtocol {
	FuchsiaIsolateDiscoveryProtocol(
	this._device,
	this._isolateName, [
	this._vmServiceConnector = _kDefaultFuchsiaIsolateDiscoveryConnector,
	this._pollOnce = false,
	]);

	static const Duration _pollDuration = Duration(seconds: 10);
	final Map<int, VMService> _ports = <int, VMService>{};
	final FuchsiaDevice _device;
	final String _isolateName;
	final Completer<Uri> _foundUri = Completer<Uri>();
	final Future<VMService> Function(Uri) _vmServiceConnector;
	// whether to only poll once.
	final bool _pollOnce;
	Timer _pollingTimer;
	Status _status;

	FutureOr<Uri> get uri {
	if (_uri != null) {
	return _uri;
	}
	_status ??= logger.startProgress(
	'Waiting for a connection from $_isolateName on ${_device.name}...',
	timeout: null, // could take an arbitrary amount of time
	);
	_pollingTimer ??= Timer(_pollDuration, _findIsolate);
	return _foundUri.future.then((Uri uri) {
	_uri = uri;
	return uri;
	});
	}

	Uri _uri;

	void dispose() {
	if (!_foundUri.isCompleted) {
	_status?.cancel();
	_status = null;
	_pollingTimer?.cancel();
	_pollingTimer = null;
	_foundUri.completeError(Exception('Did not complete'));
	}
	}

	Future<void> _findIsolate() async {
	final List<int> ports = await _device.servicePorts();
	for (int port in ports) {
	VMService service;
	if (_ports.containsKey(port)) {
	service = _ports[port];
	} else {
	final int localPort = await _device.portForwarder.forward(port);
	try {
	final Uri uri = Uri.parse('http://[$_ipv6Loopback]:$localPort');
	service = await _vmServiceConnector(uri);
	_ports[port] = service;
	} on SocketException catch (err) {
	printTrace('Failed to connect to $localPort: $err');
	continue;
	}
	}
	await service.getVM();
	await service.refreshViews();
	for (FlutterView flutterView in service.vm.views) {
	if (flutterView.uiIsolate == null) {
	continue;
	}
	final Uri address = flutterView.owner.vmService.httpAddress;
	if (flutterView.uiIsolate.name.contains(_isolateName)) {
	_foundUri.complete(_device.ipv6
	? Uri.parse('http://[$_ipv6Loopback]:${address.port}/')
	: Uri.parse('http://$_ipv4Loopback:${address.port}/'));
	_status.stop();
	return;
	}
	}
	}
	if (_pollOnce) {
	_foundUri.completeError(Exception('Max iterations exceeded'));
	_status.stop();
	return;
	}
	_pollingTimer = Timer(_pollDuration, _findIsolate);
	}
	}

	class _FuchsiaPortForwarder extends DevicePortForwarder {
	_FuchsiaPortForwarder(this.device);

	final FuchsiaDevice device;
	final Map<int, Process> _processes = <int, Process>{};

	@override
	Future<int> forward(int devicePort, {int hostPort}) async {
	hostPort ??= await os.findFreePort();
	if (hostPort == 0) {
	throwToolExit('Failed to forward port $devicePort. No free host-side ports');
	}
	// Note: the provided command works around a bug in -N, see US-515
	// for more explanation.
	final List<String> command = <String>[
	'ssh',
	'-6',
	'-F',
	fuchsiaArtifacts.sshConfig.absolute.path,
	'-nNT',
	'-vvv',
	'-f',
	'-L',
	'$hostPort:$_ipv4Loopback:$devicePort',
	device.id,
	'true',
	];
	final Process process = await processManager.start(command);
	unawaited(process.exitCode.then((int exitCode) {
	if (exitCode != 0) {
	throwToolExit('Failed to forward port:$devicePort');
	}
	}));
	_processes[hostPort] = process;
	_forwardedPorts.add(ForwardedPort(hostPort, devicePort));
	return hostPort;
	}

	@override
	List<ForwardedPort> get forwardedPorts => _forwardedPorts;
	final List<ForwardedPort> _forwardedPorts = <ForwardedPort>[];

	@override
	Future<void> unforward(ForwardedPort forwardedPort) async {
	_forwardedPorts.remove(forwardedPort);
	final Process process = _processes.remove(forwardedPort.hostPort);
	process?.kill();
	final List<String> command = <String>[
	'ssh',
	'-F',
	fuchsiaArtifacts.sshConfig.absolute.path,
	'-O',
	'cancel',
	'-vvv',
	'-L',
	'${forwardedPort.hostPort}:$_ipv4Loopback:${forwardedPort.devicePort}',
	device.id
	];
	final ProcessResult result = await processManager.run(command);
	if (result.exitCode != 0) {
	throwToolExit(result.stderr);
	}
	}
	}