Get Media folders from node

src/Umbraco.Web.UI.Client/src/common/resources/media.resource.js

@@ -392,7 +392,45 @@ function mediaResource($q, $http, umbDataFormatter, umbRequestHelper) {
                     }),
                 'Failed to add folder');
         },
-
+        
+        /**
+         * @ngdoc method
+         * @name umbraco.resources.mediaResource#getChildFolders
+         * @methodOf umbraco.resources.mediaResource
+         *
+         * @description
+         * Retrieves all media children with types used as folders.
+         * Uses the convention of looking for media items with mediaTypes ending in
+         * *Folder so will match "Folder", "bannerFolder", "secureFolder" etc,
+         *
+         * ##usage
+         * <pre>
+         * mediaResource.getChildFolders(1234)
+         *    .then(function(data) {
+         *        alert('folders');
+         *    });
+         * </pre> 
+         *
+         * @param {int} parentId Id of the media item to query for child folders    
+         * @returns {Promise} resourcePromise object.
+         *
+         */
+        getChildFolders: function(parentId){
+            if(!parentId){
+                parentId = -1;
+            }
+            
+            return umbRequestHelper.resourcePromise(
+               $http.get(
+                   umbRequestHelper.getApiUrl(
+                       "mediaApiBaseUrl",
+                       "GetChildFolders",
+                       [
+                           { id: parentId }
+                       ])),
+               'Failed to retrieve child folders for media item ' + parentId);
+        },
+            
         /**
          * @ngdoc method
          * @name umbraco.resources.mediaResource#emptyRecycleBin

src/Umbraco.Web/Editors/MediaController.cs

@@ -118,6 +118,21 @@ namespace Umbraco.Web.Editors
             return foundMedia.Select(Mapper.Map<IMedia, MediaItemDisplay>);
         }
 
+        /// <summary>
+        /// Returns media items known to be a container of other media items
+        /// </summary>
+        /// <param name="ids"></param>
+        /// <returns></returns>
+        [FilterAllowedOutgoingMedia(typeof(IEnumerable<MediaItemDisplay>))]
+        public IEnumerable<MediaItemDisplay> GetChildFolders(int id = -1)
+        {
+            //Suggested convention for folder mediatypes - we can make this more or less complicated as long as we document it...
+            //if you create a media type, which has an alias that ends with ...Folder then its a folder: ex: "secureFolder", "bannerFolder", "Folder"
+            var folderTypes = Services.ContentTypeService.GetAllMediaTypes().Where(x => x.Alias.EndsWith("Folder")).Select(x => x.Id);
+
+            var children = (id < 0) ? Services.MediaService.GetRootMedia() : Services.MediaService.GetById(id).Children();
+            return children.Where(x =>  folderTypes.Contains(x.ContentTypeId)).Select(Mapper.Map<IMedia, MediaItemDisplay>);
+        }
 
         /// <summary>
         /// Returns the root media objects