| // 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. |
| |
| import 'dart:async'; |
| import 'dart:io'; |
| |
| import 'src/directory_watcher.dart'; |
| import 'src/file_watcher.dart'; |
| import 'src/watch_event.dart'; |
| |
| export 'src/custom_watcher_factory.dart' |
| show |
| CustomWatcherFactory, |
| registerCustomWatcherFactory, |
| unregisterCustomWatcherFactory; |
| export 'src/directory_watcher.dart'; |
| export 'src/directory_watcher/polling.dart'; |
| export 'src/file_watcher.dart'; |
| export 'src/file_watcher/polling.dart'; |
| export 'src/watch_event.dart'; |
| |
| abstract class Watcher { |
| /// The path to the file or directory whose contents are being monitored. |
| String get path; |
| |
| /// The broadcast [Stream] of events that have occurred to the watched file or |
| /// files in the watched directory. |
| /// |
| /// Changes will only be monitored while this stream has subscribers. Any |
| /// 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 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 |
| /// changes. |
| /// |
| /// If the watcher is not currently monitoring the file or 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] or [FileWatcher] monitoring [path], |
| /// depending on whether it's a file or directory. |
| /// |
| /// If a native watcher is available for this platform, this will use it. |
| /// Otherwise, it will fall back to a polling watcher. Notably, watching |
| /// individual files is not natively supported on Windows, although watching |
| /// directories is. |
| /// |
| /// If [pollingDelay] is passed, it specifies the amount of time the watcher |
| /// will pause between successive polls of the contents of [path]. 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 Watcher(String path, {Duration pollingDelay}) { |
| if (File(path).existsSync()) { |
| return FileWatcher(path, pollingDelay: pollingDelay); |
| } else { |
| return DirectoryWatcher(path, pollingDelay: pollingDelay); |
| } |
| } |
| } |