Merge branch 'master' into pr/636

tests/document/instance.py

@@ -15,7 +15,7 @@ from tests.fixtures import (PickleEmbedded, PickleTest, PickleSignalsTest,
 
 from mongoengine import *
 from mongoengine.errors import (NotRegistered, InvalidDocumentError,
-                                InvalidQueryError)
+                                InvalidQueryError, NotUniqueError)
 from mongoengine.queryset import NULLIFY, Q
 from mongoengine.connection import get_db
 from mongoengine.base import get_document
@@ -57,7 +57,7 @@ class InstanceTest(unittest.TestCase):
             date = DateTimeField(default=datetime.now)
             meta = {
                 'max_documents': 10,
-                'max_size': 90000,
+                'max_size': 4096,
             }
 
         Log.drop_collection()
@@ -75,7 +75,7 @@ class InstanceTest(unittest.TestCase):
         options = Log.objects._collection.options()
         self.assertEqual(options['capped'], True)
         self.assertEqual(options['max'], 10)
-        self.assertEqual(options['size'], 90000)
+        self.assertTrue(options['size'] >= 4096)
 
         # Check that the document cannot be redefined with different options
         def recreate_log_document():
@@ -820,6 +820,80 @@ class InstanceTest(unittest.TestCase):
         p1.reload()
         self.assertEqual(p1.name, p.parent.name)
 
+    def test_save_atomicity_condition(self):
+
+        class Widget(Document):
+            toggle = BooleanField(default=False)
+            count = IntField(default=0)
+            save_id = UUIDField()
+
+        def flip(widget):
+            widget.toggle = not widget.toggle
+            widget.count += 1
+
+        def UUID(i):
+            return uuid.UUID(int=i)
+
+        Widget.drop_collection()
+        
+        w1 = Widget(toggle=False, save_id=UUID(1))
+
+        # ignore save_condition on new record creation
+        w1.save(save_condition={'save_id':UUID(42)})
+        w1.reload()
+        self.assertFalse(w1.toggle)
+        self.assertEqual(w1.save_id, UUID(1))
+        self.assertEqual(w1.count, 0)
+
+        # mismatch in save_condition prevents save
+        flip(w1)
+        self.assertTrue(w1.toggle)
+        self.assertEqual(w1.count, 1)
+        w1.save(save_condition={'save_id':UUID(42)})
+        w1.reload()
+        self.assertFalse(w1.toggle)
+        self.assertEqual(w1.count, 0)
+
+        # matched save_condition allows save
+        flip(w1)
+        self.assertTrue(w1.toggle)
+        self.assertEqual(w1.count, 1)
+        w1.save(save_condition={'save_id':UUID(1)})
+        w1.reload()
+        self.assertTrue(w1.toggle)
+        self.assertEqual(w1.count, 1)
+
+        # save_condition can be used to ensure atomic read & updates
+        # i.e., prevent interleaved reads and writes from separate contexts
+        w2 = Widget.objects.get()
+        self.assertEqual(w1, w2)
+        old_id = w1.save_id
+
+        flip(w1)
+        w1.save_id = UUID(2)
+        w1.save(save_condition={'save_id':old_id})
+        w1.reload()
+        self.assertFalse(w1.toggle)
+        self.assertEqual(w1.count, 2)
+        flip(w2)
+        flip(w2)
+        w2.save(save_condition={'save_id':old_id})
+        w2.reload()
+        self.assertFalse(w2.toggle)
+        self.assertEqual(w2.count, 2)
+
+        # save_condition uses mongoengine-style operator syntax
+        flip(w1)
+        w1.save(save_condition={'count__lt':w1.count})
+        w1.reload()
+        self.assertTrue(w1.toggle)
+        self.assertEqual(w1.count, 3)
+        flip(w1)
+        w1.save(save_condition={'count__gte':w1.count})
+        w1.reload()
+        self.assertTrue(w1.toggle)
+        self.assertEqual(w1.count, 3)
+        
     def test_update(self):
         """Ensure that an existing document is updated instead of be
         overwritten."""
@@ -990,6 +1064,16 @@ class InstanceTest(unittest.TestCase):
 
         self.assertRaises(InvalidQueryError, update_no_op_raises)
 
+    def test_update_unique_field(self):
+        class Doc(Document):
+            name = StringField(unique=True)
+
+        doc1 = Doc(name="first").save()
+        doc2 = Doc(name="second").save()
+
+        self.assertRaises(NotUniqueError, lambda:
+                          doc2.update(set__name=doc1.name))
+
     def test_embedded_update(self):
         """
         Test update on `EmbeddedDocumentField` fields
@@ -2415,7 +2499,7 @@ class InstanceTest(unittest.TestCase):
                 for parameter_name, parameter in self.parameters.iteritems():
                     parameter.expand()
 
-        class System(Document):
+        class NodesSystem(Document):
             name = StringField(required=True)
             nodes = MapField(ReferenceField(Node, dbref=False))
 
@@ -2423,18 +2507,18 @@ class InstanceTest(unittest.TestCase):
                 for node_name, node in self.nodes.iteritems():
                     node.expand()
                     node.save(*args, **kwargs)
-                super(System, self).save(*args, **kwargs)
+                super(NodesSystem, self).save(*args, **kwargs)
 
-        System.drop_collection()
+        NodesSystem.drop_collection()
         Node.drop_collection()
 
-        system = System(name="system")
+        system = NodesSystem(name="system")
         system.nodes["node"] = Node()
         system.save()
         system.nodes["node"].parameters["param"] = Parameter()
         system.save()
 
-        system = System.objects.first()
+        system = NodesSystem.objects.first()
         self.assertEqual("UNDEFINED", system.nodes["node"].parameters["param"].macros["test"].value)
 
     def test_embedded_document_equality(self):