| // Copyright (c) 2013, the Dart project authors. Please see the AUTHORS file |
| // for details. All rights reserved. Use of this source code is governed by a |
| // BSD-style license that can be found in the LICENSE file. |
| |
| library watcher.directory_watcher; |
| |
| import 'dart:async'; |
| import 'dart:io'; |
| |
| import 'watch_event.dart'; |
| import 'directory_watcher/linux.dart'; |
| import 'directory_watcher/mac_os.dart'; |
| import 'directory_watcher/windows.dart'; |
| import 'directory_watcher/polling.dart'; |
| |
| /// Watches the contents of a directory and emits [WatchEvent]s when something |
| /// in the directory has changed. |
| abstract class DirectoryWatcher { |
| /// The directory whose contents are being monitored. |
| String get directory; |
| |
| /// The broadcast [Stream] of events that have occurred to files in |
| /// [directory]. |
| /// |
| /// Changes will only be monitored while this stream has subscribers. Any |
| /// file changes that occur during periods when there are no subscribers |
| /// will not be reported the next time a subscriber is added. |
| Stream<WatchEvent> get events; |
| |
| /// Whether the watcher is initialized and watching for file changes. |
| /// |
| /// This is true if and only if [ready] is complete. |
| bool get isReady; |
| |
| /// A [Future] that completes when the watcher is initialized and watching |
| /// for file changes. |
| /// |
| /// If the watcher is not currently monitoring the directory (because there |
| /// are no subscribers to [events]), this returns a future that isn't |
| /// complete yet. It will complete when a subscriber starts listening and |
| /// the watcher finishes any initialization work it needs to do. |
| /// |
| /// If the watcher is already monitoring, this returns an already complete |
| /// future. |
| Future get ready; |
| |
| /// Creates a new [DirectoryWatcher] monitoring [directory]. |
| /// |
| /// If a native directory watcher is available for this platform, this will |
| /// use it. Otherwise, it will fall back to a [PollingDirectoryWatcher]. |
| /// |
| /// If [_pollingDelay] is passed, it specifies the amount of time the watcher |
| /// will pause between successive polls of the directory contents. Making this |
| /// shorter will give more immediate feedback at the expense of doing more IO |
| /// and higher CPU usage. Defaults to one second. Ignored for non-polling |
| /// watchers. |
| factory DirectoryWatcher(String directory, {Duration pollingDelay}) { |
| if (FileSystemEntity.isWatchSupported) { |
| if (Platform.isLinux) return new LinuxDirectoryWatcher(directory); |
| if (Platform.isMacOS) return new MacOSDirectoryWatcher(directory); |
| if (Platform.isWindows) return new WindowsDirectoryWatcher(directory); |
| } |
| return new PollingDirectoryWatcher(directory, pollingDelay: pollingDelay); |
| } |
| } |