Using "id" in data not "_id" as its a mapping of fieldnames (#255)

docs/changelog.rst

@@ -10,7 +10,7 @@ Changes in 0.7.10
 - Added Django sessions TTL support (#224)
 - Fixed issue with numerical keys in MapField(EmbeddedDocumentField()) (#240)
 - Fixed clearing _changed_fields for complex nested embedded documents (#237, #239, #242)
-- Added "_id" to _data dictionary (#255)
+- Added "id" back to _data dictionary (#255)
 - Only mark a field as changed if the value has changed (#258)
 - Explicitly check for Document instances when dereferencing (#261)
 - Fixed order_by chaining issue (#265)

mongoengine/base.py

@@ -192,7 +192,7 @@ class BaseField(object):
             return self
 
         # Get value from document instance if available, if not use default
-        value = instance._data.get(self.name or self.db_field)
+        value = instance._data.get(self.name)
 
         if value is None:
             value = self.default
@@ -207,9 +207,9 @@ class BaseField(object):
         """
         changed = False
         if (self.name not in instance._data or
-           instance._data[self.name or self.db_field] != value):
+           instance._data[self.name] != value):
             changed = True
-            instance._data[self.name or self.db_field] = value
+            instance._data[self.name] = value
         if changed and instance._initialised:
             instance._mark_as_changed(self.name)
 
@@ -825,6 +825,7 @@ class TopLevelDocumentMetaclass(DocumentMetaclass):
         if not new_class._meta.get('id_field'):
             new_class._meta['id_field'] = 'id'
             new_class._fields['id'] = ObjectIdField(db_field='_id')
+            new_class._fields['id'].name = 'id'
             new_class.id = new_class._fields['id']
 
         # Merge in exceptions with parent hierarchy
@@ -915,7 +916,7 @@ class BaseDocument(object):
                 if name in values:
                     raise TypeError("Multiple values for keyword argument '" + name + "'")
                 values[name] = value
-        
+
         signals.pre_init.send(self.__class__, document=self, values=values)
 
         self._data = {}
@@ -1138,7 +1139,7 @@ class BaseDocument(object):
         self._changed_fields = []
         EmbeddedDocumentField = _import_class("EmbeddedDocumentField")
         for field_name, field in self._fields.iteritems():
-            if (isinstance(field, ComplexBaseField) and 
+            if (isinstance(field, ComplexBaseField) and
                 isinstance(field.field, EmbeddedDocumentField)):
                 field_value = getattr(self, field_name, None)
                 if field_value:
@@ -1331,7 +1332,7 @@ class BaseDocument(object):
     def __iter__(self):
         if 'id' in self._fields and 'id' not in self._fields_ordered:
             return iter(('id', ) + self._fields_ordered)
-        
+
         return iter(self._fields_ordered)
 
     def __getitem__(self, name):

tests/test_document.py

@@ -1386,27 +1386,27 @@ class DocumentTest(unittest.TestCase):
         person = self.Person(name="Test User", age=30)
         self.assertEqual(person.name, "Test User")
         self.assertEqual(person.age, 30)
-    
+
     def test_positional_creation(self):
         """Ensure that document may be created using positional arguments.
         """
         person = self.Person("Test User", 42)
         self.assertEqual(person.name, "Test User")
         self.assertEqual(person.age, 42)
-    
+
     def test_mixed_creation(self):
         """Ensure that document may be created using mixed arguments.
         """
         person = self.Person("Test User", age=42)
         self.assertEqual(person.name, "Test User")
         self.assertEqual(person.age, 42)
-    
+
     def test_bad_mixed_creation(self):
         """Ensure that document gives correct error when duplicating arguments
         """
         def construct_bad_instance():
             return self.Person("Test User", 42, name="Bad User")
-        
+
         self.assertRaises(TypeError, construct_bad_instance)
 
     def test_to_dbref(self):
@@ -1553,8 +1553,8 @@ class DocumentTest(unittest.TestCase):
         self.assertEqual(2, len(keys))
         self.assertTrue('e' in keys)
         # Ensure that the _id field has the right id
-        self.assertTrue('_id' in keys)
+        self.assertTrue('id' in keys)
-        self.assertEqual(doc._data.get('_id'), doc.id)
+        self.assertEqual(doc._data.get('id'), doc.id)
 
     def test_save(self):
         """Ensure that a document may be saved in the database.
@@ -3402,8 +3402,8 @@ class DocumentTest(unittest.TestCase):
         Person(name="Harry Potter").save()
 
         person = Person.objects.first()
-        self.assertTrue('_id' in person._data.keys())
+        self.assertTrue('id' in person._data.keys())
-        self.assertEqual(person._data.get('_id'), person.id)
+        self.assertEqual(person._data.get('id'), person.id)
 
     def test_complex_nesting_document_and_embedded_document(self):