Update GetContentTypeDescriptors() cache on Save(), Delete()

While many updates to the configuration metadata are made available in real time, some—such as adding or deleting `ContentTypeDescriptor`s—are not. This is because the `TopicRepositoryBase.GetContentTypeDecriptors()` method caches the list of content types so that it doesn't need to reload it from the persistence store each time its called.

To mitigate this, we can dynamically update the `GetContentTypeDescriptors()` cache when we call `Save()` or `Delete()`. Specifically, if `Save()` is called with a `ContentTypeDescriptor` and that content type is new, then it will be added to the local `_contentTypeDescriptors` collection. Similarly, if `Delete()` is called with a `ContentTypeDescriptor` then that content type—along with all descendent content types—will be removed from the _contentTypeDescriptors` collection.

This satisfies the requirements of the newly proposed feature enhancement: Update content type cache when adding or removing content types (#16).

Author: JeremyCaney

OnTopic.Tests/TopicRepositoryBaseTest.cs

@@ -200,5 +200,45 @@ public void GetContentTypeDescriptor_GetInvalidContentType_ReturnsNull() {
 
     }
 
+    /*==========================================================================================================================
+    | TEST: SAVE: CONTENT TYPE DESCRIPTOR: UPDATES CONTENT TYPE CACHE
+    \-------------------------------------------------------------------------------------------------------------------------*/
+    /// <summary>
+    ///   Loads the <see cref="TopicRepositoryBase.GetAttributes(Topic, Boolean?, Boolean?)"/>, then saves a new <see
+    ///   cref="ContentTypeDescriptor"/> via <see cref="TopicRepositoryBase.Save(Topic, Boolean, Boolean)"/>, and ensures that
+    ///   it is immediately reflected in the <see cref="TopicRepositoryBase"/> cache of <see cref="ContentTypeDescriptor"/>s.
+    /// </summary>
+    [TestMethod]
+    public void Save_ContentTypeDescriptor_UpdatesContentTypeCache() {
+
+      var contentTypes          = _topicRepository.GetContentTypeDescriptors();
+      var topic                 = TopicFactory.Create("NewContentType", "ContentTypeDescriptor");
+
+      _topicRepository.Save(topic);
+
+      Assert.IsTrue(contentTypes.Contains(topic));
+
+    }
+
+    /*==========================================================================================================================
+    | TEST: DELETE: CONTENT TYPE DESCRIPTOR: UPDATES CONTENT TYPE CACHE
+    \-------------------------------------------------------------------------------------------------------------------------*/
+    /// <summary>
+    ///   Loads the <see cref="TopicRepositoryBase.GetAttributes(Topic, Boolean?, Boolean?)"/>, then deletes one of the <see
+    ///   cref="ContentTypeDescriptor"/>s via <see cref="TopicRepositoryBase.Delete(Topic, Boolean)"/>, and ensures that it is
+    ///   immediately reflected in the <see cref="TopicRepositoryBase"/> cache of <see cref="ContentTypeDescriptor"/>s.
+    /// </summary>
+    [TestMethod]
+    public void Delete_ContentTypeDescriptor_UpdatesContentTypeCache() {
+
+      var contentTypes          = _topicRepository.GetContentTypeDescriptors();
+      var contentType           = contentTypes.Contains("Page")? contentTypes["Page"] : null;
+
+      _topicRepository.Delete(contentType);
+
+      Assert.IsFalse(contentTypes.Contains(contentType));
+
+    }
+
   } //Class
 } //Namespace

OnTopic/Repositories/TopicRepositoryBase.cs

@@ -315,6 +315,18 @@ public virtual int Save([ValidatedNotNull, NotNull]Topic topic, bool isRecursive
         }
       }
 
+      /*------------------------------------------------------------------------------------------------------------------------
+      | If new content type, remove from cache
+      \-----------------------------------------------------------------------------------------------------------------------*/
+      if (
+        topic.Id < 0 &&
+        topic is ContentTypeDescriptor &&
+        _contentTypeDescriptors != null &&
+        !_contentTypeDescriptors.Contains(topic)
+      ) {
+        _contentTypeDescriptors.Add((ContentTypeDescriptor)topic);
+      }
+
       /*------------------------------------------------------------------------------------------------------------------------
       | Reset original key
       \-----------------------------------------------------------------------------------------------------------------------*/
@@ -403,6 +415,17 @@ public virtual void Delete([ValidatedNotNull, NotNull]Topic topic, bool isRecurs
         topic.Parent.Children.Remove(topic.Key);
       }
 
+      /*------------------------------------------------------------------------------------------------------------------------
+      | If content type, remove from cache
+      \-----------------------------------------------------------------------------------------------------------------------*/
+      if (topic is ContentTypeDescriptor && _contentTypeDescriptors != null) {
+        foreach (var contentTypeDescriptor in topic.FindAll(t => t is ContentTypeDescriptor).Cast<ContentTypeDescriptor>()) {
+          if (_contentTypeDescriptors.Contains(contentTypeDescriptor)) {
+            _contentTypeDescriptors.Remove(contentTypeDescriptor);
+          }
+        }
+      }
+
     }
 
     /*==========================================================================================================================