Merge pull request #168 from MongoEngine/auto-field

Auto field fix

Author: last-partizan

django_mongoengine/document.py

@@ -14,7 +14,7 @@
 # TopLevelDocumentMetaclass is using ObjectIdField to create default pk field,
 # if one's not set explicitly.
 # We need to know it's not editable and auto_created.
-#mtc.ObjectIdField = partial(ObjectIdField, editable=False, auto_created=True)
+mtc.ObjectIdField = partial(ObjectIdField, editable=False, auto_created=True, blank=True)
 
 
 def django_meta(meta, *top_bases):

django_mongoengine/fields/__init__.py

@@ -35,9 +35,6 @@ def patch_mongoengine_field(field_name):
     for k in ["__eq__", "__lt__", "__hash__", "attname", "get_internal_type"]:
         if k not in field.__dict__:
             setattr(field, k, djangoflavor.DjangoField.__dict__[k])
-    # set auto_created False for check in django db model when delete
-    if field_name == "ObjectIdField":
-        setattr(field, "auto_created", False)
 
 
 init_module()