flutter/packages/flutter_tools/lib/src/base/process_manager.dart
2017-01-23 09:46:38 -08:00

85 lines
3.3 KiB
Dart

// 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 'package:process/process.dart';
import 'package:process/record_replay.dart';
import 'common.dart';
import 'context.dart';
import 'file_system.dart';
import 'process.dart';
/// The active process manager.
ProcessManager get processManager => context[ProcessManager];
/// Enables recording of process invocation activity to the specified location.
///
/// This sets the [active process manager](processManager) to one that records
/// all process activity before delegating to a [LocalProcessManager].
///
/// [location] must either represent a valid, empty directory or a non-existent
/// file system entity, in which case a directory will be created at that path.
/// Process invocation activity will be serialized to opaque files in that
/// directory. The resulting (populated) directory will be suitable for use
/// with [enableReplayProcessManager].
void enableRecordingProcessManager(String location) {
if (location.isEmpty)
throwToolExit('record-to location not specified');
switch (fs.typeSync(location, followLinks: false)) {
case FileSystemEntityType.FILE:
case FileSystemEntityType.LINK:
throwToolExit('record-to location must reference a directory');
break;
case FileSystemEntityType.DIRECTORY:
if (fs.directory(location).listSync(followLinks: false).isNotEmpty)
throwToolExit('record-to directory must be empty');
break;
case FileSystemEntityType.NOT_FOUND:
fs.directory(location).createSync(recursive: true);
}
Directory dir = fs.directory(location);
ProcessManager delegate = new LocalProcessManager();
RecordingProcessManager manager = new RecordingProcessManager(delegate, dir);
addShutdownHook(() async {
await manager.flush(finishRunningProcesses: true);
});
context.setVariable(ProcessManager, manager);
}
/// Enables process invocation replay mode.
///
/// This sets the [active process manager](processManager) to one that replays
/// process activity from a previously recorded set of invocations.
///
/// [location] must represent a directory to which process activity has been
/// recorded (i.e. the result of having been previously passed to
/// [enableRecordingProcessManager]).
Future<Null> enableReplayProcessManager(String location) async {
if (location.isEmpty)
throwToolExit('replay-from location not specified');
Directory dir = fs.directory(location);
if (!dir.existsSync())
throwToolExit('replay-from location must reference a directory');
ProcessManager manager;
try {
manager = await ReplayProcessManager.create(dir,
// TODO(tvolkert): Once https://github.com/flutter/flutter/issues/7166 is
// resolved, we can use the default `streamDelay`. In the
// meantime, native file I/O operations cause our `tail` process
// streams to flush before our protocol discovery is listening on
// them, causing us to timeout waiting for the observatory port.
streamDelay: const Duration(milliseconds: 50),
);
} on ArgumentError catch (error) {
throwToolExit('Invalid replay-from: $error');
}
context.setVariable(ProcessManager, manager);
}