Accept meta fields mappings with or without leading _

elasticsearch_dsl/document.py

@@ -54,7 +54,7 @@ def __init__(self, name, bases, attrs):
         # add all the mappings for meta fields
         for name in dir(meta):
             if isinstance(getattr(meta, name, None), MetaField):
-                self.mapping.meta('_' + name if not name.startswith('_') else name, **getattr(meta, name))
+                self.mapping.meta(name, **getattr(meta, name))
 
         # document inheritance - include the fields from parents' mappings and
         # index/using values

elasticsearch_dsl/mapping.py

@@ -114,6 +114,9 @@ def field(self, *args, **kwargs):
         return self
 
     def meta(self, name, **kwargs):
+        if not name.startswith('_'):
+            name = '_' + name
+
         if not kwargs:
             if name in self._meta:
                 del self._meta[name]