Fixed an issue where the duplicate checker plugin could dos itself.

Author: niemyjski

src/Exceptionless/ExceptionlessClient.cs

@@ -185,10 +185,8 @@ public void SubmitEvent(Event ev, ContextData pluginContextData = null) {
 
             var context = new EventPluginContext(this, ev, pluginContextData);
             EventPluginManager.Run(context);
-            if (context.Cancel) {
-                _log.Value.FormattedInfo(typeof(ExceptionlessClient), "Event submission cancelled by a plugin: id={0} type={1}", ev.ReferenceId, ev.Type);
+            if (context.Cancel)
                 return;
-            }
 
             // ensure all required data
             if (String.IsNullOrEmpty(ev.Type))
@@ -197,7 +195,7 @@ public void SubmitEvent(Event ev, ContextData pluginContextData = null) {
                 ev.Date = DateTimeOffset.Now;
 
             if (!OnSubmittingEvent(ev, pluginContextData)) {
-                _log.Value.FormattedInfo(typeof(ExceptionlessClient), "Event submission cancelled by event handler: id={0} type={1}", ev.ReferenceId, ev.Type);
+                _log.Value.FormattedInfo(typeof(ExceptionlessClient), "Event submission cancelled by event handler: refid={0} type={1} message={2}", ev.ReferenceId, ev.Type, ev.Message);
                 return;
             }
 

src/Exceptionless/Plugins/ContextData.cs

@@ -38,7 +38,7 @@ public bool IsUnhandledError {
 
                 if (!(this[KnownKeys.IsUnhandledError] is bool))
                     return false;
-                
+
                 return (bool)this[KnownKeys.IsUnhandledError];
             }
         }

src/Exceptionless/Plugins/Default/1010_DuplicateCheckerPlugin.cs

@@ -9,6 +9,8 @@
 namespace Exceptionless.Plugins.Default {
     [Priority(1010)]
     public class DuplicateCheckerPlugin : IEventPlugin, IDisposable {
+        private const string LOG_SOURCE = nameof(DuplicateCheckerPlugin);
+        private static readonly Type _logSourceType = typeof(DuplicateCheckerPlugin);
         private readonly Queue<Tuple<int, DateTimeOffset>> _processed = new Queue<Tuple<int, DateTimeOffset>>();
         private readonly Queue<MergedEvent> _mergedEvents = new Queue<MergedEvent>();
         private readonly object _lock = new object();
@@ -30,33 +32,36 @@ public DuplicateCheckerPlugin(TimeSpan? interval) {
         }
 
         public void Run(EventPluginContext context) {
+            if (LOG_SOURCE == context.Event.Source)
+                return;
+
             int hashCode = context.Event.GetHashCode();
             int count = context.Event.Count ?? 1;
-            context.Log.FormattedTrace(typeof(DuplicateCheckerPlugin), "Checking event: {0} with hash: {1}", context.Event.Message, hashCode);
+            context.Log.FormattedTrace(_logSourceType, "Checking event: {0} with hash: {1}", context.Event.Message, hashCode);
 
             lock (_lock) {
                 // Increment the occurrence count if the event is already queued for submission.
                 var merged = _mergedEvents.FirstOrDefault(s => s.HashCode == hashCode);
                 if (merged != null) {
                     merged.IncrementCount(count);
                     merged.UpdateDate(context.Event.Date);
-                    context.Log.FormattedInfo(typeof(DuplicateCheckerPlugin), "Ignoring duplicate event with hash: {0}", hashCode);
+                    context.Log.FormattedInfo(_logSourceType, "Ignoring duplicate event: {0} with hash: {1}", context.Event.Message, hashCode);
                     context.Cancel = true;
                     return;
                 }
 
                 DateTimeOffset repeatWindow = DateTimeOffset.UtcNow.Subtract(_interval);
                 if (_processed.Any(s => s.Item1 == hashCode && s.Item2 >= repeatWindow)) {
-                    context.Log.FormattedTrace(typeof(DuplicateCheckerPlugin), "Adding event with hash: {0} to cache.", hashCode);
+                    context.Log.FormattedTrace(_logSourceType, "Adding duplicate event: {0} with hash: {1} to cache for later submission.", context.Event.Message, hashCode);
                     // This event is a duplicate for the first time, lets save it so we can delay it while keeping count
                     _mergedEvents.Enqueue(new MergedEvent(hashCode, context, count));
                     context.Cancel = true;
                     return;
                 }
 
-                context.Log.FormattedTrace(typeof(DuplicateCheckerPlugin), "Enqueueing event with hash: {0} to cache.", hashCode);
+                context.Log.FormattedTrace(_logSourceType, "Enqueueing event with hash: {0} to cache.", hashCode);
                 _processed.Enqueue(Tuple.Create(hashCode, DateTimeOffset.UtcNow));
-                
+
                 while (_processed.Count > 50)
                     _processed.Dequeue();
             }
@@ -108,15 +113,15 @@ public void Resubmit() {
                     _context.Event.Date = DateTimeOffset.Now;
 
                 if (!_context.Client.OnSubmittingEvent(_context.Event, _context.ContextData)) {
-                    _context.Log.FormattedInfo(typeof(DuplicateCheckerPlugin), "Event submission cancelled by event handler: id={0} type={1}", _context.Event.ReferenceId, _context.Event.Type);
+                    _context.Log.FormattedInfo(_logSourceType, "Event submission cancelled by event handler: id={0} type={1}", _context.Event.ReferenceId, _context.Event.Type);
                     return;
                 }
 
-                _context.Log.FormattedTrace(typeof(DuplicateCheckerPlugin), "Submitting event: type={0}{1}", _context.Event.Type, !String.IsNullOrEmpty(_context.Event.ReferenceId) ? " refid=" + _context.Event.ReferenceId : String.Empty);
+                _context.Log.FormattedTrace(_logSourceType, "Submitting event: type={0}{1}", _context.Event.Type, !String.IsNullOrEmpty(_context.Event.ReferenceId) ? " refid=" + _context.Event.ReferenceId : String.Empty);
                 _context.Resolver.GetEventQueue().Enqueue(_context.Event);
 
                 if (!String.IsNullOrEmpty(_context.Event.ReferenceId)) {
-                    _context.Log.FormattedTrace(typeof(DuplicateCheckerPlugin), "Setting last reference id: {0}", _context.Event.ReferenceId);
+                    _context.Log.FormattedTrace(_logSourceType, "Setting last reference id: {0}", _context.Event.ReferenceId);
                     _context.Resolver.GetLastReferenceIdManager().SetLast(_context.Event.ReferenceId);
                 }
 

src/Exceptionless/Plugins/EventPluginManager.cs

@@ -14,7 +14,7 @@ public static void Run(EventPluginContext context) {
                 try {
                     plugin.Run(context);
                     if (context.Cancel) {
-                        context.Log.FormattedInfo(plugin.GetType(), "Event submission cancelled by plugin: id={0} type={1}", context.Event.ReferenceId, context.Event.Type);
+                        context.Log.FormattedInfo(plugin.GetType(), "Event submission cancelled by plugin: refid={0} type={1} message={2}", context.Event.ReferenceId, context.Event.Type, context.Event.Message);
                         return;
                     }
                 } catch (Exception ex) {

src/Platforms/Exceptionless.Web/RequestInfoCollector.cs

@@ -43,10 +43,10 @@ public static RequestInfo Collect(HttpContextBase context, ExceptionlessConfigur
 
             if (context.Request.Url != null)
                 info.Port = context.Request.Url.Port;
-            
+
             var exclusionList = config.DataExclusions as string[] ?? config.DataExclusions.ToArray();
             info.Cookies = context.Request.Cookies.ToDictionary(exclusionList);
-            
+
             if (context.Request.Form.Count > 0) {
                 info.PostData = context.Request.Form.ToDictionary(exclusionList);
             } else if (context.Request.ContentLength > 0) {