Updating FileWatcherEverntSource to avoid publishing events after disposal. Throwing from ScriptEventManager if Publish or Subscribe are called after disposal.

Author: fabiocav

src/WebJobs.Script/Eventing/File/FileWatcherEventSource.cs

@@ -31,8 +31,11 @@ public FileWatcherEventSource(IScriptEventManager eventManager,
 
         private void FileChanged(object sender, FileSystemEventArgs e)
         {
-            var fileEvent = new FileEvent(_source, e);
-            _eventManager.Publish(fileEvent);
+            if (!_disposed)
+            {
+                var fileEvent = new FileEvent(_source, e);
+                _eventManager.Publish(fileEvent);
+            }
         }
 
         private void Dispose(bool disposing)

src/WebJobs.Script/Eventing/ScriptEventManager.cs

@@ -11,9 +11,27 @@ public sealed class ScriptEventManager : IScriptEventManager, IDisposable
         private readonly Subject<ScriptEvent> _subject = new Subject<ScriptEvent>();
         private bool _disposed = false;
 
-        public void Publish(ScriptEvent scriptEvent) => _subject.OnNext(scriptEvent);
+        public void Publish(ScriptEvent scriptEvent)
+        {
+            ThrowIfDisposed();
+
+            _subject.OnNext(scriptEvent);
+        }
 
-        public IDisposable Subscribe(IObserver<ScriptEvent> observer) => _subject.Subscribe(observer);
+        public IDisposable Subscribe(IObserver<ScriptEvent> observer)
+        {
+            ThrowIfDisposed();
+
+            return _subject.Subscribe(observer);
+        }
+
+        private void ThrowIfDisposed()
+        {
+            if (_disposed)
+            {
+                throw new ObjectDisposedException(nameof(ScriptEventManager));
+            }
+        }
 
         private void Dispose(bool disposing)
         {