Merge pull request #371 from apjaffe/master

Adds the ConditionalCheckFailedException to put_item

moto/dynamodb2/models.py

@@ -191,7 +191,7 @@ class Table(object):
                     keys.append(key['AttributeName'])
         return keys
 
-    def put_item(self, item_attrs):
+    def put_item(self, item_attrs, expected = None, overwrite = False):
         hash_value = DynamoType(item_attrs.get(self.hash_key_attr))
         if self.has_range_key:
             range_value = DynamoType(item_attrs.get(self.range_key_attr))
@@ -200,6 +200,35 @@ class Table(object):
 
         item = Item(hash_value, self.hash_key_type, range_value, self.range_key_type, item_attrs)
 
+        if not overwrite:
+            if expected is None:
+                expected = {}
+                lookup_range_value = range_value
+            else:
+                expected_range_value = expected.get(self.range_key_attr, {}).get("Value")
+                if(expected_range_value is None):
+                    lookup_range_value = range_value
+                else:
+                    lookup_range_value = DynamoType(expected_range_value)
+
+            current = self.get_item(hash_value, lookup_range_value)
+
+            if current is None:
+                current_attr = {}
+            elif hasattr(current,'attrs'):
+                current_attr = current.attrs
+            else:
+                current_attr = current
+
+            for key, val in expected.items():
+                if 'Exists' in val and val['Exists'] == False:
+                    if key in current_attr:
+                        raise ValueError("The conditional request failed")
+                elif key not in current_attr:
+                    raise ValueError("The conditional request failed")
+                elif DynamoType(val['Value']).value != current_attr[key].value:
+                    raise ValueError("The conditional request failed")
+
         if range_value:
             self.items[hash_value][range_value] = item
         else:
@@ -317,11 +346,11 @@ class DynamoDBBackend(BaseBackend):
         table.throughput = throughput
         return table
 
-    def put_item(self, table_name, item_attrs):
+    def put_item(self, table_name, item_attrs, expected = None, overwrite = False):
         table = self.tables.get(table_name)
         if not table:
             return None
-        return table.put_item(item_attrs)
+        return table.put_item(item_attrs, expected, overwrite)
 
     def get_table_keys_name(self, table_name, keys):
         """

moto/dynamodb2/responses.py

@@ -134,7 +134,17 @@ class DynamoHandler(BaseResponse):
     def put_item(self):
         name = self.body['TableName']
         item = self.body['Item']
-        result = dynamodb_backend2.put_item(name, item)
+        overwrite = 'Expected' not in self.body
+        if not overwrite:
+            expected = self.body['Expected']
+        else:
+            expected = None
+
+        try:
+            result = dynamodb_backend2.put_item(name, item, expected, overwrite)
+        except Exception:
+            er = 'com.amazonaws.dynamodb.v20111205#ConditionalCheckFailedException'
+            return self.error(er)
 
         if result:
             item_dict = result.to_json()

tests/test_dynamodb2/test_dynamodb_table_with_range_key.py

@@ -10,6 +10,7 @@ try:
     from boto.dynamodb2.fields import GlobalAllIndex, HashKey, RangeKey
     from boto.dynamodb2.table import Item, Table
     from boto.dynamodb2.exceptions import ValidationException
+    from boto.dynamodb2.exceptions import ConditionalCheckFailedException
 except ImportError:
     pass
 
@@ -553,3 +554,52 @@ def test_lookup():
     message = table.lookup(hash_key, range_key)
     message.get('test_hash').should.equal(Decimal(hash_key))
     message.get('test_range').should.equal(Decimal(range_key))
+
+
+@mock_dynamodb2
+def test_failed_overwrite():
+    from decimal import Decimal
+    table = Table.create('messages', schema=[
+        HashKey('id'),
+        RangeKey('range'),
+    ], throughput={
+        'read': 7,
+        'write': 3,
+    })
+
+    data1 = {'id': '123', 'range': 'abc', 'data':'678'}
+    table.put_item(data=data1)
+
+    data2 = {'id': '123', 'range': 'abc', 'data':'345'}
+    table.put_item(data=data2, overwrite = True)
+
+    data3 = {'id': '123', 'range': 'abc', 'data':'812'}
+    table.put_item.when.called_with(data=data3).should.throw(ConditionalCheckFailedException)
+
+    returned_item = table.lookup('123', 'abc')
+    dict(returned_item).should.equal(data2)
+
+    data4 = {'id': '123', 'range': 'ghi', 'data':812}
+    table.put_item(data=data4)
+
+    returned_item = table.lookup('123', 'ghi')
+    dict(returned_item).should.equal(data4)
+
+
+@mock_dynamodb2
+def test_conflicting_writes():
+    table = Table.create('messages', schema=[
+        HashKey('id'),
+        RangeKey('range'),
+    ])
+
+    item_data = {'id': '123', 'range':'abc', 'data':'678'}
+    item1 = Item(table, item_data)
+    item2 = Item(table, item_data)
+    item1.save()
+
+    item1['data'] = '579'
+    item2['data'] = '912'
+
+    item1.save()
+    item2.save.when.called_with().should.throw(ConditionalCheckFailedException)

tests/test_dynamodb2/test_dynamodb_table_without_range_key.py

@@ -10,6 +10,7 @@ try:
     from boto.dynamodb2.fields import HashKey
     from boto.dynamodb2.table import Table
     from boto.dynamodb2.table import Item
+    from boto.dynamodb2.exceptions import ConditionalCheckFailedException
 except ImportError:
     pass
 
@@ -437,3 +438,50 @@ def test_update_item_set():
         'foo': 'bar',
         'blah': 'baz',
     })
+
+
+@mock_dynamodb2
+def test_failed_overwrite():
+    from decimal import Decimal
+    table = Table.create('messages', schema=[
+        HashKey('id'),
+    ], throughput={
+        'read': 7,
+        'write': 3,
+    })
+
+    data1 = {'id': '123', 'data':'678'}
+    table.put_item(data=data1)
+
+    data2 = {'id': '123', 'data':'345'}
+    table.put_item(data=data2, overwrite = True)
+
+    data3 = {'id': '123', 'data':'812'}
+    table.put_item.when.called_with(data=data3).should.throw(ConditionalCheckFailedException)
+
+    returned_item = table.lookup('123')
+    dict(returned_item).should.equal(data2)
+
+    data4 = {'id': '124', 'data':812}
+    table.put_item(data=data4)
+
+    returned_item = table.lookup('124')
+    dict(returned_item).should.equal(data4)
+
+
+@mock_dynamodb2
+def test_conflicting_writes():
+    table = Table.create('messages', schema=[
+        HashKey('id'),
+    ])
+
+    item_data = {'id': '123', 'data':'678'}
+    item1 = Item(table, item_data)
+    item2 = Item(table, item_data)
+    item1.save()
+
+    item1['data'] = '579'
+    item2['data'] = '912'
+
+    item1.save()
+    item2.save.when.called_with().should.throw(ConditionalCheckFailedException)