It is very convenient to update a web form from any computer. It may also be useful to update it purely from the filesystem so that a standard text editor can be used or we can have the blog post content entirely automated.

The watcher package provides the functionality needed for this feature. This package is authored by the Dart team and is typically of the Dart philosophy of being a small focused library. The DirectoryWatcher class takes a path and notifies via events if any files have added, removed, or modified.

The Blog class constructor configures the path that is going to be watched by the DirectoryWatcher. Let's take a look at the following screenshot:

  DirectoryWatcher _changeMonitor;

  Blog(this._pathPosts, this._pathImgs) {
    initBlog();
    _changeMonitor = new DirectoryWatcher(this._pathPosts);
    _changeMonitor.events.listen((watchEvent) => initBlog());
  }

The actual details of the change are not important for the blog, so the initBlog method will...