// Copyright 2016 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 'dart:convert'; import '../base/common.dart'; import '../base/file_system.dart'; import '../base/utils.dart'; import '../device.dart'; import '../globals.dart'; import '../runner/flutter_command.dart'; import '../vmservice.dart'; const String _kOut = 'out'; const String _kSkia = 'skia'; class ScreenshotCommand extends FlutterCommand { ScreenshotCommand() { argParser.addOption( _kOut, abbr: 'o', help: 'Location to write the screenshot.', ); argParser.addOption( _kSkia, valueHelp: 'port', help: 'Retrieve the last frame rendered by a Flutter app as a Skia picture\n' 'using the specified observatory port.\n' 'To find the observatory port number, use "flutter run --verbose"\n' 'and look for "Forwarded host port ... for Observatory" in the output.' ); } @override String get name => 'screenshot'; @override String get description => 'Take a screenshot from a connected device.'; @override final List<String> aliases = <String>['pic']; Device device; @override Future<Null> verifyThenRunCommand() async { device = await findTargetDevice(); if (device == null) throwToolExit('Must have a connected device'); if (!device.supportsScreenshot && argResults[_kSkia] == null) throwToolExit('Screenshot not supported for ${device.name}.'); return super.verifyThenRunCommand(); } @override Future<Null> runCommand() async { File outputFile; if (argResults.wasParsed(_kOut)) outputFile = fs.file(argResults[_kOut]); if (argResults[_kSkia] != null) { return runSkia(outputFile); } else { return runScreenshot(outputFile); } } Future<Null> runScreenshot(File outputFile) async { outputFile ??= getUniqueFile(fs.currentDirectory, 'flutter', 'png'); try { await device.takeScreenshot(outputFile); } catch (error) { throwToolExit('Error taking screenshot: $error'); } await showOutputFileInfo(outputFile); } Future<Null> runSkia(File outputFile) async { final Uri observatoryUri = new Uri(scheme: 'http', host: '127.0.0.1', port: int.parse(argResults[_kSkia])); final VMService vmService = await VMService.connect(observatoryUri); final Map<String, dynamic> skp = await vmService.vm.invokeRpcRaw('_flutter.screenshotSkp'); outputFile ??= getUniqueFile(fs.currentDirectory, 'flutter', 'skp'); final IOSink sink = outputFile.openWrite(); sink.add(base64.decode(skp['skp'])); await sink.close(); await showOutputFileInfo(outputFile); if (await outputFile.length() < 1000) { final String content = await outputFile.readAsString( encoding: const AsciiCodec(allowInvalid: true), ); if (content.startsWith('{"jsonrpc":"2.0", "error"')) throwToolExit('\nIt appears the output file contains an error message, not valid skia output.'); } } Future<Null> showOutputFileInfo(File outputFile) async { final int sizeKB = (await outputFile.length()) ~/ 1024; printStatus('Screenshot written to ${fs.path.relative(outputFile.path)} (${sizeKB}kB).'); } }