firewall_gui: provide default values for new Rule objects

firewall_gui/views.py

@@ -168,8 +168,9 @@ def list_entities(request, name):
         }[name](request)), content_type='application/json')
 
 
-def show_rule(request, id):
-    rule = get_object_or_404(Rule, id=id)
+def show_rule(request, id=None):
+    try:
+        rule = Rule.objects.get(id=id)
         rule = {
             'id': rule.id,
             'target': {
@@ -220,6 +221,34 @@ def show_rule(request, id):
             'extra': rule.extra,
             'nat_dport': rule.nat_dport
         }
+    except:
+        rule = {
+            'id': None,
+            'target': { 'id': None, 'name': None, 'type': None },
+            'type': None,
+            'direction': {
+                'value': None,
+                'choices': Rule._meta.get_field_by_name('direction')[0].choices,
+            },
+            'proto': {
+                'value': None,
+                'choices': Rule._meta.get_field_by_name('proto')[0].choices,
+            },
+            'owner': {
+                'id': None,
+                'name': None,
+            },
+            'foreignNetwork': { 'name': None, 'id': None },
+            'created_at': None,
+            'modified_at': None,
+            'nat': False,
+            'accept': False,
+            'description': '',
+            'dport': None,
+            'sport': None,
+            'extra': '',
+            'nat_dport': None,
+        }
     return HttpResponse(json.dumps(rule), content_type='application/json')