Fix filtering by embedded_doc=None

Fix BaseQuerySet#sum and BaseQuerySet#average for fields that specify a db_field

README.rst

@@ -52,10 +52,14 @@ Some simple examples of what MongoEngine code looks like:
 
 .. code :: python
 
+    from mongoengine import *
+    connect('mydb')
+
     class BlogPost(Document):
         title = StringField(required=True, max_length=200)
         posted = DateTimeField(default=datetime.datetime.now)
         tags = ListField(StringField(max_length=50))
+        meta = {'allow_inheritance': True}
 
     class TextPost(BlogPost):
         content = StringField(required=True)

docs/changelog.rst

@@ -4,14 +4,15 @@ Changelog
 
 Changes in 0.10.8
 =================
-- Fill this in as PRs for v0.10.8 are merged
+- Added ability to specify an authentication mechanism (e.g. X.509) #1333
+- Added support for falsey primary keys (e.g. doc.pk = 0) #1354
+- Fixed BaseQuerySet#sum/average for fields w/ explicit db_field #1417
 
 Changes in 0.10.7
 =================
 - Dropped Python 3.2 support #1390
 - Fixed the bug where dynamic doc has index inside a dict field #1278
 - Fixed: ListField minus index assignment does not work #1128
-- Fixed not being able to specify `use_db_field=False` on `ListField(EmbeddedDocumentField)` instances
 - Fixed cascade delete mixing among collections #1224
 - Add `signal_kwargs` argument to `Document.save`, `Document.delete` and `BaseQuerySet.insert` to be passed to signals calls #1206
 - Raise `OperationError` when trying to do a `drop_collection` on document with no collection set.
@@ -28,7 +29,7 @@ Changes in 0.10.7
 - Fixed connecting to a list of hosts #1389
 - Fixed a bug where accessing broken references wouldn't raise a DoesNotExist error #1334
 - Fixed not being able to specify use_db_field=False on ListField(EmbeddedDocumentField) instances #1218
-- Improvements to the dictionary fields docs # 1383
+- Improvements to the dictionary fields docs #1383
 
 Changes in 0.10.6
 =================

mongoengine/connection.py

@@ -6,6 +6,7 @@ __all__ = ['ConnectionError', 'connect', 'register_connection',
 
 
 DEFAULT_CONNECTION_NAME = 'default'
+
 if IS_PYMONGO_3:
     READ_PREFERENCE = ReadPreference.PRIMARY
 else:
@@ -25,6 +26,7 @@ _dbs = {}
 def register_connection(alias, name=None, host=None, port=None,
                         read_preference=READ_PREFERENCE,
                         username=None, password=None, authentication_source=None,
+                        authentication_mechanism=None,
                         **kwargs):
     """Add a connection.
 
@@ -38,6 +40,9 @@ def register_connection(alias, name=None, host=None, port=None,
     :param username: username to authenticate with
     :param password: password to authenticate with
     :param authentication_source: database to authenticate against
+    :param authentication_mechanism: database authentication mechanisms.
+        By default, use SCRAM-SHA-1 with MongoDB 3.0 and later,
+        MONGODB-CR (MongoDB Challenge Response protocol) for older servers.
     :param is_mock: explicitly use mongomock for this connection
         (can also be done by using `mongomock://` as db host prefix)
     :param kwargs: allow ad-hoc parameters to be passed into the pymongo driver
@@ -53,9 +58,11 @@ def register_connection(alias, name=None, host=None, port=None,
         'read_preference': read_preference,
         'username': username,
         'password': password,
-        'authentication_source': authentication_source
+        'authentication_source': authentication_source,
+        'authentication_mechanism': authentication_mechanism
     }
 
+    # Handle uri style connections
     conn_host = conn_settings['host']
     # host can be a list or a string, so if string, force to a list
     if isinstance(conn_host, str_types):
@@ -82,6 +89,8 @@ def register_connection(alias, name=None, host=None, port=None,
                 conn_settings['replicaSet'] = True
             if 'authsource' in uri_options:
                 conn_settings['authentication_source'] = uri_options['authsource']
+            if 'authmechanism' in uri_options:
+                conn_settings['authentication_mechanism'] = uri_options['authmechanism']
         else:
             resolved_hosts.append(entity)
     conn_settings['host'] = resolved_hosts
@@ -123,6 +132,7 @@ def get_connection(alias=DEFAULT_CONNECTION_NAME, reconnect=False):
         conn_settings.pop('username', None)
         conn_settings.pop('password', None)
         conn_settings.pop('authentication_source', None)
+        conn_settings.pop('authentication_mechanism', None)
 
         is_mock = conn_settings.pop('is_mock', None)
         if is_mock:
@@ -157,6 +167,7 @@ def get_connection(alias=DEFAULT_CONNECTION_NAME, reconnect=False):
                 connection_settings.pop('username', None)
                 connection_settings.pop('password', None)
                 connection_settings.pop('authentication_source', None)
+                connection_settings.pop('authentication_mechanism', None)
                 if conn_settings == connection_settings and _connections.get(db_alias, None):
                     connection = _connections[db_alias]
                     break
@@ -176,11 +187,13 @@ def get_db(alias=DEFAULT_CONNECTION_NAME, reconnect=False):
         conn = get_connection(alias)
         conn_settings = _connection_settings[alias]
         db = conn[conn_settings['name']]
+        auth_kwargs = {'source': conn_settings['authentication_source']}
+        if conn_settings['authentication_mechanism'] is not None:
+            auth_kwargs['mechanism'] = conn_settings['authentication_mechanism']
         # Authenticate if necessary
-        if conn_settings['username'] and conn_settings['password']:
-            db.authenticate(conn_settings['username'],
-                            conn_settings['password'],
-                            source=conn_settings['authentication_source'])
+        if conn_settings['username'] and (conn_settings['password'] or
+                                          conn_settings['authentication_mechanism'] == 'MONGODB-X509'):
+            db.authenticate(conn_settings['username'], conn_settings['password'], **auth_kwargs)
         _dbs[alias] = db
     return _dbs[alias]
 

mongoengine/document.py

@@ -472,7 +472,7 @@ class Document(BaseDocument):
         Raises :class:`OperationError` if called on an object that has not yet
         been saved.
         """
-        if not self.pk:
+        if self.pk is None:
             if kwargs.get('upsert', False):
                 query = self.to_mongo()
                 if "_cls" in query:
@@ -604,7 +604,7 @@ class Document(BaseDocument):
         elif "max_depth" in kwargs:
             max_depth = kwargs["max_depth"]
 
-        if not self.pk:
+        if self.pk is None:
             raise self.DoesNotExist("Document does not exist")
         obj = self._qs.read_preference(ReadPreference.PRIMARY).filter(
             **self._object_key).only(*fields).limit(
@@ -655,7 +655,7 @@ class Document(BaseDocument):
     def to_dbref(self):
         """Returns an instance of :class:`~bson.dbref.DBRef` useful in
         `__raw__` queries."""
-        if not self.pk:
+        if self.pk is None:
             msg = "Only saved documents can have a valid dbref"
             raise OperationError(msg)
         return DBRef(self.__class__._get_collection_name(), self.pk)

mongoengine/fields.py

@@ -577,7 +577,7 @@ class EmbeddedDocumentField(BaseField):
         return self.document_type._fields.get(member_name)
 
     def prepare_query_value(self, op, value):
-        if not isinstance(value, self.document_type):
+        if value is not None and not isinstance(value, self.document_type):
             value = self.document_type._from_son(value)
         super(EmbeddedDocumentField, self).prepare_query_value(op, value)
         return self.to_mongo(value)

tests/document/instance.py

@@ -3202,5 +3202,20 @@ class InstanceTest(unittest.TestCase):
             self.assertEqual(b._instance, a)
         self.assertEqual(idx, 2)
 
+    def test_falsey_pk(self):
+        """Ensure that we can create and update a document with Falsey PK.
+        """
+        class Person(Document):
+            age = IntField(primary_key=True)
+            height = FloatField()
+
+        person = Person()
+        person.age = 0
+        person.height = 1.89
+        person.save()
+
+        person.update(set__height=2.0)
+
+
 if __name__ == '__main__':
     unittest.main()

tests/queryset/queryset.py

@@ -1239,7 +1239,8 @@ class QuerySetTest(unittest.TestCase):
             self.assertFalse('$orderby' in q.get_ops()[0]['query'])
 
     def test_find_embedded(self):
-        """Ensure that an embedded document is properly returned from a query.
+        """Ensure that an embedded document is properly returned from
+        a query.
         """
         class User(EmbeddedDocument):
             name = StringField()
@@ -1250,16 +1251,31 @@ class QuerySetTest(unittest.TestCase):
 
         BlogPost.drop_collection()
 
-        post = BlogPost(content='Had a good coffee today...')
-        post.author = User(name='Test User')
-        post.save()
+        BlogPost.objects.create(
+            author=User(name='Test User'),
+            content='Had a good coffee today...'
+        )
 
         result = BlogPost.objects.first()
         self.assertTrue(isinstance(result.author, User))
         self.assertEqual(result.author.name, 'Test User')
 
+    def test_find_empty_embedded(self):
+        """Ensure that you can save and find an empty embedded document."""
+        class User(EmbeddedDocument):
+            name = StringField()
+
+        class BlogPost(Document):
+            content = StringField()
+            author = EmbeddedDocumentField(User)
+
         BlogPost.drop_collection()
 
+        BlogPost.objects.create(content='Anonymous post...')
+
+        result = BlogPost.objects.get(author=None)
+        self.assertEqual(result.author, None)
+
     def test_find_dict_item(self):
         """Ensure that DictField items may be found.
         """