Merge pull request #345 from amcgregor/master

Addition of pre_save_validation and move of pre_save to after validation.

mongoengine/document.py

@@ -195,7 +195,7 @@ class Document(BaseDocument):
             the cascade save using cascade_kwargs which overwrites the
             existing kwargs with custom values
         """
-        signals.pre_save.send(self.__class__, document=self)
+        signals.pre_save_validation.send(self.__class__, document=self)
 
         if validate:
             self.validate(clean=clean)
@@ -206,7 +206,9 @@ class Document(BaseDocument):
         doc = self.to_mongo()
 
         created = ('_id' not in doc or self._created or force_insert)
-
+        
+        signals.pre_save.send(self.__class__, document=self, created=created)
+        
         try:
             collection = self._get_collection()
             if created:

mongoengine/signals.py

@@ -1,7 +1,7 @@
 # -*- coding: utf-8 -*-
 
-__all__ = ['pre_init', 'post_init', 'pre_save', 'post_save',
-           'pre_delete', 'post_delete']
+__all__ = ['pre_init', 'post_init', 'pre_save_validation', 'pre_save',
+           'post_save', 'pre_delete', 'post_delete']
 
 signals_available = False
 try:
@@ -38,6 +38,7 @@ _signals = Namespace()
 
 pre_init = _signals.signal('pre_init')
 post_init = _signals.signal('post_init')
+pre_save_validation = _signals.signal('pre_save_validation')
 pre_save = _signals.signal('pre_save')
 post_save = _signals.signal('post_save')
 pre_delete = _signals.signal('pre_delete')