use required html5 attribute

gadget_json_generated_form.js

@@ -598,8 +598,9 @@
     return queue;
   }
 
-  function render_field(gadget, key, path, json_field, default_value, root, schema_path, type) {
-    var div,
+  function render_field(gadget, key, path, json_field, default_value, root, schema_path, options) {
+    var type,
+      div,
       label,
       div_input,
       span_info,
@@ -608,6 +609,9 @@
       first_path,
       queue = RSVP.Queue();
 
+    options = options || {};
+    type = options.type;
+
     if (path && key) {
       first_path = path + encodeJsonPointer(key);
     } else {
@@ -719,6 +723,7 @@
       // gadget.props.inputs not contain values
       gadget.props.inputs.push(input);
       input.name = first_path;
+      input.required = options.required;
       // XXX for gui
       //input.setAttribute("class", "slapos-parameter");
       div_input.appendChild(input);
@@ -840,7 +845,7 @@
           }
           queue
             .push(render_field.bind(g, g, key, path,
-                json_field.properties[key], default_dict[key], root)
+                json_field.properties[key], default_dict[key], root, schema_path, {required: true})
               );
         } else if (default_dict.hasOwnProperty(key)) {
           used_properties[key] = "";
@@ -1333,7 +1338,7 @@
         root.appendChild(delete_button);
       }
       return render_field(g, property_name, "", schema,
-        options.document, root, options.schema_path, options.type)
+        options.document, root, options.schema_path, {type: options.type})
         .push(function () {
           g.listenEvents();
           return g.element;