Prevent cache of pages with notifications

src/Orchard.Web/Modules/Orchard.OutputCache/Filters/OutputCacheFilter.cs

@@ -40,7 +40,6 @@ namespace Orchard.OutputCache.Filters {
         private readonly ISignals _signals;
         private readonly ShellSettings _shellSettings;
         private readonly ICacheControlStrategy _cacheControlStrategy;
-        private readonly INotifier _notifier;
 
         TextWriter _originalWriter;
         StringWriter _cachingWriter;
@@ -59,8 +58,7 @@ namespace Orchard.OutputCache.Filters {
             ICacheService cacheService,
             ISignals signals,
             ShellSettings shellSettings,
-            ICacheControlStrategy cacheControlStrategy, 
-            INotifier notifier) {
+            ICacheControlStrategy cacheControlStrategy) {
 
             _cacheManager = cacheManager;
             _cacheStorageProvider = cacheStorageProvider;
@@ -73,7 +71,6 @@ namespace Orchard.OutputCache.Filters {
             _signals = signals;
             _shellSettings = shellSettings;
             _cacheControlStrategy = cacheControlStrategy;
-            _notifier = notifier;
 
             Logger = NullLogger.Instance;
         }
@@ -347,7 +344,9 @@ namespace Orchard.OutputCache.Filters {
             }
 
             // don't cache the result if there were some notifications
-            if (_notifier.List().Any()) {
+            var hasNotifications = !String.IsNullOrEmpty(Convert.ToString(filterContext.Controller.TempData["messages"]));
+            if (hasNotifications) {
+                Logger.Debug("Not caching: notifications present");
                 return;
             }
 
@@ -375,10 +374,8 @@ namespace Orchard.OutputCache.Filters {
 
             Logger.Debug("Cache item added: " + _cacheItem.CacheKey);
 
-            // remove only the current version of the page
-            _cacheService.RemoveByTag(_cacheKey);
-
-            // add data to cache
+            // update the cached data
+            _cacheStorageProvider.Remove(_cacheKey);
             _cacheStorageProvider.Set(_cacheKey, _cacheItem);
 
             // add to the tags index

src/Orchard.Web/Modules/Orchard.OutputCache/Services/CacheService.cs

@@ -40,6 +40,9 @@ namespace Orchard.OutputCache.Services {
             foreach(var key in _tagCache.GetTaggedItems(tag)) {
                 _cacheStorageProvider.Remove(key);
             }
+
+            // we no longer need the tag entry as the items have been removed
+            _tagCache.RemoveTag(tag);
         }
 
         public IEnumerable<CacheItem> GetCacheItems() {

src/Orchard.Web/Modules/Orchard.OutputCache/Services/DefaultTagCache.cs

@@ -37,5 +37,10 @@ namespace Orchard.OutputCache.Services {
 
             return Enumerable.Empty<string>();
         }
+
+        public void RemoveTag(string tag) {
+            HashSet<string> set;
+            _dictionary.TryRemove(tag, out set);
+        }
     }
 }

src/Orchard.Web/Modules/Orchard.OutputCache/Services/ITagCache.cs

@@ -4,5 +4,6 @@ namespace Orchard.OutputCache.Services {
     public interface ITagCache : ISingletonDependency {
         void Tag(string tag, params string[] keys);
         IEnumerable<string> GetTaggedItems(string tag);
+        void RemoveTag(string tag);
     }
 }