Support async in TreeController

src/Umbraco.Web.BackOffice/Trees/ApplicationTreeController.cs

@@ -349,7 +349,7 @@ private async Task<ActionResult<object>> GetApiControllerProxy(Type controllerTy
 
             var actionContext = new ActionContext(HttpContext, routeData, actionDescriptor);
             var proxyControllerContext = new ControllerContext(actionContext);
-            var controller = (TreeController)_controllerFactory.CreateController(proxyControllerContext);
+            var controller = (TreeControllerBase)_controllerFactory.CreateController(proxyControllerContext);
 
             // TODO: What about other filters? Will they execute?
             var isAllowed = await controller.ControllerContext.InvokeAuthorizationFiltersForRequest(actionContext);

src/Umbraco.Web.BackOffice/Trees/TreeControllerBase.cs

@@ -57,6 +57,37 @@ protected TreeControllerBase(UmbracoApiControllerTypeCollection apiControllers,
         /// <returns></returns>
         protected abstract ActionResult<MenuItemCollection> GetMenuForNode(string id, [ModelBinder(typeof(HttpQueryStringModelBinder))]FormCollection queryStrings);
 
+        /// <summary>
+        /// The method called to render the contents of the tree structure
+        /// </summary>
+        /// <param name="id"></param>
+        /// <param name="queryStrings">
+        /// All of the query string parameters passed from jsTree
+        /// </param>
+        /// <remarks>
+        /// If overriden, GetTreeNodes will not be called
+        /// We are allowing an arbitrary number of query strings to be passed in so that developers are able to persist custom data from the front-end
+        /// to the back end to be used in the query for model data.
+        /// </remarks>
+        protected virtual async Task<ActionResult<TreeNodeCollection>> GetTreeNodesAsync(string id, [ModelBinder(typeof(HttpQueryStringModelBinder))] FormCollection queryStrings)
+        {
+            return GetTreeNodes(id, queryStrings);
+        }
+
+        /// <summary>
+        /// Returns the menu structure for the node
+        /// </summary>
+        /// <param name="id"></param>
+        /// <param name="queryStrings"></param>
+        /// <returns></returns>
+        /// <remarks>
+        /// If overriden, GetMenuForNode will not be called
+        /// </remarks>
+        protected virtual async Task<ActionResult<MenuItemCollection>> GetMenuForNodeAsync(string id, [ModelBinder(typeof(HttpQueryStringModelBinder))] FormCollection queryStrings)
+        {
+            return GetMenuForNode(id, queryStrings);
+        }
+
         /// <summary>
         /// The name to display on the root node
         /// </summary>
@@ -132,7 +163,7 @@ public async Task<ActionResult<TreeNode>> GetRootNode([ModelBinder(typeof(HttpQu
         public async Task<ActionResult<TreeNodeCollection>> GetNodes(string id, [ModelBinder(typeof(HttpQueryStringModelBinder))]FormCollection queryStrings)
         {
             if (queryStrings == null) queryStrings = FormCollection.Empty;
-            var nodesResult = GetTreeNodes(id, queryStrings);
+            var nodesResult = await GetTreeNodesAsync(id, queryStrings);
 
             if (!(nodesResult.Result is null))
             {
@@ -150,7 +181,7 @@ public async Task<ActionResult<TreeNodeCollection>> GetNodes(string id, [ModelBi
                     node.RoutePath = "#";
 
             //raise the event
-            await _eventAggregator.PublishAsync(new TreeNodesRenderingNotification(nodes, queryStrings, TreeAlias));
+            await _eventAggregator.PublishAsync(new TreeNodesRenderingNotification(nodes, queryStrings, TreeAlias, id));
 
             return nodes;
         }
@@ -164,7 +195,7 @@ public async Task<ActionResult<TreeNodeCollection>> GetNodes(string id, [ModelBi
         public async Task<ActionResult<MenuItemCollection>> GetMenu(string id, [ModelBinder(typeof(HttpQueryStringModelBinder))]FormCollection queryStrings)
         {
             if (queryStrings == null) queryStrings = FormCollection.Empty;
-            var menuResult = GetMenuForNode(id, queryStrings);
+            var menuResult = await GetMenuForNodeAsync(id, queryStrings);
             if (!(menuResult.Result is null))
             {
                 return menuResult.Result;

src/Umbraco.Web.BackOffice/Trees/TreeNodesRenderingNotification.cs

@@ -26,11 +26,17 @@ public class TreeNodesRenderingNotification : INotification
         /// </summary>
         public string TreeAlias { get; }
 
-        public TreeNodesRenderingNotification(TreeNodeCollection nodes, FormCollection queryString, string treeAlias)
+        /// <summary>
+        /// Gets id of the node rendered
+        /// </summary>
+        public string Id { get; }
+
+        public TreeNodesRenderingNotification(TreeNodeCollection nodes, FormCollection queryString, string treeAlias, string id)
         {
             Nodes = nodes;
             QueryString = queryString;
             TreeAlias = treeAlias;
+            Id = id;
         }
     }
 }