Issue LIBCLOUD-365. check types

libcloud/compute/drivers/ec2.py

@@ -1332,10 +1332,17 @@ def create_node(self, **kwargs):
             params['ClientToken'] = kwargs['ex_clienttoken']
 
         if 'ex_blockdevicemappings' in kwargs:
+            if not isinstance(kwargs['ex_blockdevicemappings'], list):
+                raise AttributeError('ex_blockdevicemappings is not a list')
+
             for idx, mapping in enumerate(kwargs['ex_blockdevicemappings'],
                                           start=1):
-                 for k, v in mapping.iteritems():
-                     params['BlockDeviceMapping.%d.%s' % (idx, k)] = str(v)
+                for k, v in mapping.items():
+                    if not isinstance(mapping, dict):
+                        raise AttributeError('mapping %s in '\
+                                            'ex_blockdevicemappings is not '\
+                                            'a dict' % mapping)
+                    params['BlockDeviceMapping.%d.%s' % (idx, k)] = str(v)
 
         object = self.connection.request(self.path, params=params).object
         nodes = self._to_nodes(object, 'instancesSet/item')

libcloud/test/compute/test_ec2.py

@@ -214,6 +214,25 @@ def test_ex_create_node_with_ex_blockdevicemappings(self):
                                        ex_blockdevicemappings=mappings)
         self.assertEqual(node.id, 'i-2ba64342')
 
+    def test_ex_create_node_with_ex_blockdevicemappings_attribute_error(self):
+        EC2MockHttp.type = 'create_ex_blockdevicemappings'
+
+        image = NodeImage(id='ami-be3adfd7',
+                          name=self.image_name,
+                          driver=self.driver)
+        size = NodeSize('m1.small', 'Small Instance', None, None, None, None,
+                        driver=self.driver)
+
+        mappings = 'this should be a list'
+        self.assertRaises(AttributeError, self.driver.create_node, name='foo',
+                                       image=image, size=size,
+                                       ex_blockdevicemappings=mappings)
+
+        mappings = ['this should be a dict']
+        self.assertRaises(AttributeError, self.driver.create_node, name='foo',
+                                       image=image, size=size,
+                                       ex_blockdevicemappings=mappings)
+
     def test_destroy_node(self):
         node = Node('i-4382922a', None, None, None, None, self.driver)
         ret = self.driver.destroy_node(node)