Revert "Remove broken external domain validation"

This reverts commit 9b1b833fac.

webadmin/src/views/apps.html

@@ -49,7 +49,7 @@
                             </div>
                         </div>
 
-                        <p class="text-center" ng-show="appConfigure.usingAltDomain && appConfigure.location">
+                        <p class="text-center" ng-show="appConfigure.usingAltDomain && appConfigure.location && appConfigure.isAltDomainValid()">
                             Add a CNAME record for {{ appConfigure.location }} to {{ appConfigure.app.fqdn }}
                             <br>
                         </p>

webadmin/src/views/apps.js

@@ -38,6 +38,11 @@ angular.module('Application').controller('AppsController', ['$scope', '$location
         isAccessRestrictionValid: function () {
             var tmp = $scope.appConfigure.accessRestriction;
             return !!(tmp.users.length || tmp.groups.length);
+        },
+
+        isAltDomainValid: function () {
+            if (!$scope.appConfigure.usingAltDomain) return true;
+            return /.+\..+\..+/.test($scope.appConfigure.location); // 2 dots
         }
     };