private void InnerSubscribeTopic(string topic)
{
if (!watchers.Keys.Contains(topic))
{
lock (watchersLocker) {
if (!watchers.Keys.Contains(topic))
{
var filePath = FileBasedPubSubUtils.GetFilePath(basePath, topic);
var fileInfo = new FileInfo(filePath);
FileSystemWatcher watcher = new FileSystemWatcher();
watcher.Path = fileInfo.DirectoryName;
watcher.Filter = fileInfo.Name;
watcher.NotifyFilter = NotifyFilters.LastWrite;
watchers[topic] = watcher;
var fileEventHandler = new FileSystemEventHandler((source, e) => {
try {
OnFileEvent(topic, source, e);
} catch (Exception ex) {
EventLogger.WriteError($"Error handling cache file event for file: {filePath}. Cache invalidation skipped.");
EventLogger.WriteError(ex);
}
});
watcher.Changed += fileEventHandler;
watcher.EnableRaisingEvents = true;
}
}
}
}
public void Dispose()
{
if (ClearFilesOnDispose)
{
subscriptions
.SelectMany(sub => sub.GetSubscribedTopics())
.Select(topic => FileBasedPubSubUtils.GetFilePath(basePath, topic))
.Where(filePath => File.Exists(filePath))
.Apply(filePath => File.Delete(filePath));
}
CancelAllSubscriptions();
subscriptions.Apply(sub => sub.Dispose());
}
public void Publish(string topic, string message)
{
var filePath = FileBasedPubSubUtils.GetFilePath(basePath, topic);
var content = Guid.NewGuid().ToString() + Constants.NewLineCharacter + message;
var fileInfo = new FileInfo(filePath);
// Yes it's nasty, I know...
Stopwatch s = new Stopwatch();
s.Start();
while (s.Elapsed < TimeSpan.FromMilliseconds(500))
{
try {
using (var writer = new StreamWriter(fileInfo.FullName)) {
writer.Write(content);
writer.Flush();
}
break;
} catch (IOException) {
}
}
s.Stop();
}