// 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 'dart:io'; import 'package:vm_service_client/vm_service_client.dart'; import 'package:flutter_devicelab/framework/utils.dart'; /// Slightly longer than task timeout that gives the task runner a chance to /// clean-up before forcefully quitting it. const Duration taskTimeoutWithGracePeriod = const Duration(minutes: 11); /// Runs a task in a separate Dart VM and collects the result using the VM /// service protocol. /// /// [taskName] is the name of the task. The corresponding task executable is /// expected to be found under `bin/tasks`. /// /// Running the task in [silent] mode will suppress standard output from task /// processes and only print standard errors. Future<Map<String, dynamic>> runTask(String taskName, { bool silent: false }) async { String taskExecutable = 'bin/tasks/$taskName.dart'; if (!file(taskExecutable).existsSync()) throw 'Executable Dart file not found: $taskExecutable'; int vmServicePort = await findAvailablePort(); Process runner = await startProcess(dartBin, <String>[ '--enable-vm-service=$vmServicePort', '--no-pause-isolates-on-exit', taskExecutable, ]); bool runnerFinished = false; runner.exitCode.whenComplete(() { runnerFinished = true; }); StreamSubscription<String> stdoutSub = runner.stdout .transform(const Utf8Decoder()) .transform(const LineSplitter()) .listen((String line) { if (!silent) { stdout.writeln('[$taskName] [STDOUT] $line'); } }); StreamSubscription<String> stderrSub = runner.stderr .transform(const Utf8Decoder()) .transform(const LineSplitter()) .listen((String line) { stderr.writeln('[$taskName] [STDERR] $line'); }); String waitingFor = 'connection'; try { VMIsolateRef isolate = await _connectToRunnerIsolate(vmServicePort); waitingFor = 'task completion'; Map<String, dynamic> taskResult = await isolate.invokeExtension('ext.cocoonRunTask').timeout(taskTimeoutWithGracePeriod); waitingFor = 'task process to exit'; await runner.exitCode.timeout(const Duration(seconds: 1)); return taskResult; } on TimeoutException catch (timeout) { runner.kill(ProcessSignal.SIGINT); return <String, dynamic>{ 'success': false, 'reason': 'Timeout waiting for $waitingFor: ${timeout.message}', }; } finally { if (!runnerFinished) runner.kill(ProcessSignal.SIGKILL); await stdoutSub.cancel(); await stderrSub.cancel(); } } Future<VMIsolateRef> _connectToRunnerIsolate(int vmServicePort) async { String url = 'ws://localhost:$vmServicePort/ws'; DateTime started = new DateTime.now(); // TODO(yjbanov): due to lack of imagination at the moment the handshake with // the task process is very rudimentary and requires this small // delay to let the task process open up the VM service port. // Otherwise we almost always hit the non-ready case first and // wait a whole 1 second, which is annoying. await new Future<Null>.delayed(const Duration(milliseconds: 100)); while (true) { try { // Make sure VM server is up by successfully opening and closing a socket. await (await WebSocket.connect(url)).close(); // Look up the isolate. VMServiceClient client = new VMServiceClient.connect(url); VM vm = await client.getVM(); VMIsolateRef isolate = vm.isolates.single; String response = await isolate.invokeExtension('ext.cocoonRunnerReady'); if (response != 'ready') throw 'not ready yet'; return isolate; } catch (error) { const Duration connectionTimeout = const Duration(seconds: 2); if (new DateTime.now().difference(started) > connectionTimeout) { throw new TimeoutException( 'Failed to connect to the task runner process', connectionTimeout, ); } print('VM service not ready yet: $error'); const Duration pauseBetweenRetries = const Duration(milliseconds: 200); print('Will retry in $pauseBetweenRetries.'); await new Future<Null>.delayed(pauseBetweenRetries); } } }