Update

myapp/ns_login/templates/login.html

@@ -40,38 +40,35 @@
 
 {% block script %}
 <script type="text/javascript">
-var app = new Vue({
-    el: '#app',
-    data: {
-        username: '',
-        password: '',
-        error: null
-    },
-    methods: {
-        login: function() {
-            let vm = this;
-            axios.post(
-                '/api',
-                {
-                    "jsonrpc": "2.0",
-                    "method": "login",
-                    "params": {
-                        "username": vm.username,
-                        "password": vm.password
-                    },
-                    "id": 1
+Object.assign(root.data, {
+    username: '',
+    password: '',
+    error: null
+});
+Object.assign(root.methods, {
+    login: function() {
+        let vm = this;
+        axios.post(
+            '/api',
+            {
+                "jsonrpc": "2.0",
+                "method": "login",
+                "params": {
+                    "username": vm.username,
+                    "password": vm.password
+                },
+                "id": 1
+            }
+        ).then(
+            function(response) {
+                if ('result' in response.data) {
+                    window.location.href = '/';
+                } else if ('error' in response.data) {
+                    vm.error = response.data['error'].message;
                 }
-            ).then(
-                function(response) {
-                    if ('result' in response.data) {
-                        window.location.href = '/';
-                    } else if ('error' in response.data) {
-                        vm.error = response.data['error'].message;
-                    }
-                }
-            );
-        }
+            }
+        );
     }
-})
+});
 </script>
 {% endblock %}