added ajax loader and improved error handling

Author: Andreas Eisenkolb

Code.gs

@@ -1,3 +1,17 @@
+/*  Copyright 2014 University of Passau
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
 /**
  * Creates a menu entry in the Google Docs UI when the document is opened.
  *
@@ -100,7 +114,9 @@ function getRecommendations() {
     }
   }
   // privacy proxy URL
-  var url = "http://eexcess-dev.joanneum.at/eexcess-privacy-proxy/api/v1/recommend";
+  var url = "http://eexcess.joanneum.at/eexcess-privacy-proxy/api/v1/recommend"; 
+  // federated recommender
+  //var url = "http://eexcess.joanneum.at/eexcess-federated-recommender-web-service-1.0-SNAPSHOT/recommender/recommend";
 
   // POST payload
   var data = { "numResults" : 60, "contextKeywords" : [] };
@@ -111,19 +127,21 @@ function getRecommendations() {
     data["contextKeywords"].push({ "weight" : 1.0 / terms.length, "text" : terms[i] });
   }
 
-  Logger.log(data);
-  
   // Options object, that specifies the method, content type and payload of the HTTPRequest
   var options = {
     "method" : "POST",
     "contentType" : "application/json",
+    "origin" : "gdocs",
+    "headers" : {
+      "Accept" : "application/json"
+    },
     "payload" : JSON.stringify(data)
   };
- 
+   
   try {
-    return UrlFetchApp.fetch(url, options).getContentText();
+    var response = UrlFetchApp.fetch(url, options);
+    return response.getContentText();
   } catch(err) {
-    
+    throw err;
   }
 }
-

Sidedbar.html

@@ -20,6 +20,10 @@
   height: 75%;
 }
 
+#ajax-loader-container {
+  text-align: center;
+  margin-top: 50px;
+}
 </style>
 
 
@@ -61,22 +65,36 @@
    */
   function getRecommendations() {
     this.disabled = true;
- 
+    // Clear previously loaded recommendations
+    $("#eexcess-recommendations-list").empty();
+    // Remove error messages
+    removeError();
+    // Insert Ajax loader icon
+    $('<div id="ajax-loader-container"><img src="http://mics.fim.uni-passau.de/wp-content/uploads/2014/10/ajax-loader.gif" width="16px" height="16px" alt="ajax loader"/></div>').insertAfter("#eexcess-recommendations-list");
+
     google.script.run
         .withSuccessHandler(
           function(recommendations, element) { 
+            
+            removeAjaxLoader();
+            var container = $("#eexcess-recommendations-list");
             // Parsing the JSON string 
             var o = JSON.parse(recommendations);
-            var container = $("#eexcess-recommendations-list");
-            // iterate the results and append the list elements
-            $.each(o.result, function() {
-               container.append("<li><a href='" + this.uri + "' target='_blank'>" + this.title + "</a></li>");
-            })
-            
+              
+            if(o.totalResults > 0) {
+              // iterate the results and append the list elements
+              $.each(o.result, function() {
+                container.append("<li><a href='" + this.uri + "' target='_blank'>" + this.title + "</a></li>");
+              })
+            } else {
+              showError("No results found", $('#button-bar'));  
+            }
+
             element.disabled = false;
           })
         .withFailureHandler(
           function(msg, element) {
+            removeAjaxLoader();
             showError(msg, $('#button-bar'));
             element.disabled = false;
           })
@@ -91,8 +109,22 @@
    * @param element The element after which to display the error.
    */
   function showError(msg, element) {
-    $("#error").remove();
+    removeError();
     var div = $('<div id="error" class="error">' + msg + '</div>');
     $(element).after(div);
   }
+  
+  /**
+   * Removes previously added error messages.
+   */
+  function removeError() {
+    $("#error").remove();
+  }
+  
+  /**
+   * Removes the ajax loader icon (spinner) from the DOM.
+   */
+  function removeAjaxLoader() {
+    $('#ajax-loader-container').remove();
+  }
 </script>