Fixing issue: EMM-1537

components/device-mgt/org.wso2.carbon.device.mgt.ui/src/main/resources/jaggeryapps/devicemgt/api/operation-api.jag

@@ -51,7 +51,12 @@ if (uriMatcher.match("/{context}/api/operation/paginate")) {
             } else {
                 response["status"] = restAPIResponse["status"];
                 if (restAPIResponse["responseText"]) {
+                    var responseText = "";
+                    try {
                         response["content"] =  parse(restAPIResponse["responseText"]);
+                    } catch (e) {
+                        responseText = restAPIResponse["responseText"];
+                    }
                 }
             }
         }

components/device-mgt/org.wso2.carbon.device.mgt.ui/src/main/resources/jaggeryapps/devicemgt/app/modules/oauth/token-protected-service-invokers.js

@@ -45,12 +45,13 @@ var invokers = function () {
      * If the token pair is not set in the session, this will return null.
      */
     privateMethods.getAccessToken = function () {
+        if (session) {
             var tokenPair = session.get(constants["TOKEN_PAIR"]);
             if (tokenPair) {
                 return parse(tokenPair)["accessToken"];
-        } else {
-            return null;
             }
+        }
+        return null;
     };
 
     /**
@@ -80,9 +81,10 @@ var invokers = function () {
 
         if (devicemgtProps["isOAuthEnabled"]) {
             var accessToken = privateMethods.getAccessToken();
-            if (!accessToken) {
+            if (accessToken == null) {
                 userModule.logout(function () {
                     response.sendRedirect(devicemgtProps["appContext"] + "login");
+                    return responseCallback({"status": 401, "responseText" : "Session expired!"});
                 });
             } else {
                 xmlHttpRequest.setRequestHeader(constants["AUTHORIZATION_HEADER"],