2.2.0 -- minor release to prepare for upgrading to 3.0.1

pynamodb/__init__.py

@@ -7,4 +7,4 @@
 """
 __author__ = 'Jharrod LaFon'
 __license__ = 'MIT'
-__version__ = '2.1.6'
+__version__ = '2.2.0'

pynamodb/attributes.py

@@ -530,6 +530,18 @@ def _get_deserialize_class(cls, key, value):
             return cls._get_attributes().get(key)
         return _get_class_for_deserialize(value)
 
+    @classmethod
+    def _has_unicode_set_attribute(cls):
+        if cls.is_raw():
+            return False
+
+        for attr_value in cls._get_attributes().values():
+            if isinstance(attr_value, UnicodeSetAttribute):
+                return True
+            if isinstance(attr_value, MapAttribute):
+                return attr_value._has_unicode_set_attribute()
+
+        return False
 
 def _get_value_for_deserialize(value):
     key = next(iter(value.keys()))

pynamodb/models.py

@@ -11,7 +11,7 @@
 from six import add_metaclass
 from pynamodb.exceptions import DoesNotExist, TableDoesNotExist, TableError
 from pynamodb.throttle import NoThrottle
-from pynamodb.attributes import Attribute, AttributeContainer, MapAttribute, ListAttribute
+from pynamodb.attributes import Attribute, AttributeContainer, MapAttribute, ListAttribute, UnicodeSetAttribute
 from pynamodb.connection.base import MetaTable
 from pynamodb.connection.table import TableConnection
 from pynamodb.connection.util import pythonic
@@ -233,6 +233,95 @@ def __init__(self, hash_key=None, range_key=None, **attrs):
             attrs[self._dynamo_to_python_attr(range_keyname)] = range_key
         self._set_attributes(**attrs)
 
+    @classmethod
+    def fix_unicode_set_attributes(cls,
+                                   get_save_kwargs,
+                                   read_capacity_to_consume_per_second=10,
+                                   max_sleep_between_retry=10,
+                                   max_consecutive_exceptions=30):
+        """
+        This function performs a rate limited scan of the table and re-serializes any UnicodeSetAttributes.
+
+        See https://github.com/pynamodb/PynamoDB/issues/377 for why this is necessary.
+
+        :param get_save_kwargs: A callback function that is passed a model and should return the kwargs
+            used when conditionally saving the item
+        :param read_capacity_to_consume_per_second: Amount of read capacity to consume
+            every second
+        :param max_sleep_between_retry: Max value for sleep in seconds in between scans during
+            throttling/rate limit scenarios
+        :param max_consecutive_exceptions: Max number of consecutive provision throughput exceeded
+            exceptions for scan to exit
+        """
+
+        if not cls._has_unicode_set_attribute():
+            return
+
+        items = cls.rate_limited_scan(
+            read_capacity_to_consume_per_second=read_capacity_to_consume_per_second,
+            max_sleep_between_retry=max_sleep_between_retry,
+            max_consecutive_exceptions=max_consecutive_exceptions
+        )
+        for item in items:
+            save_kwargs = get_save_kwargs(item)
+            item.save(**save_kwargs)
+
+    @classmethod
+    def _has_unicode_set_attribute(cls):
+        for attr_value in cls._get_attributes().values():
+            if isinstance(attr_value, UnicodeSetAttribute):
+                return True
+            if isinstance(attr_value, MapAttribute):
+                return attr_value._has_unicode_set_attribute()
+        return False
+
+    @classmethod
+    def needs_unicode_set_fix(cls,
+                              read_capacity_to_consume_per_second=10,
+                              max_sleep_between_retry=10,
+                              max_consecutive_exceptions=30):
+
+        if not cls._has_unicode_set_attribute():
+            return False
+
+        scan_result = cls._get_connection().rate_limited_scan(
+            read_capacity_to_consume_per_second=read_capacity_to_consume_per_second,
+            max_sleep_between_retry=max_sleep_between_retry,
+            max_consecutive_exceptions=max_consecutive_exceptions,
+        )
+
+        ret_val = False
+        for item in scan_result:
+            ret_val |= cls._has_json_unicode_set_value(item)
+        return ret_val
+
+    @classmethod
+    def _has_json_unicode_set_value(cls, data):
+        ret_val = False
+        for name, attr in data.items():
+            # attr should be a map of attribute type to value
+            (attr_type, attr_value), = attr.items()
+            if attr_type == 'M':
+                ret_val |= cls._has_json_unicode_set_value(attr_value)
+            elif attr_type == 'L':
+                for value in attr_value:
+                    (at, av), = value.items()
+                    ret_val |= cls._attr_has_json_unicode_set_value(at, av)
+            else:
+                ret_val |= cls._attr_has_json_unicode_set_value(attr_type, attr_value)
+        return ret_val
+
+    @classmethod
+    def _attr_has_json_unicode_set_value(cls, attr_type, value):
+        if attr_type != 'SS':
+            return False
+        for val in value:
+            try:
+                result = json.loads(val)
+            except ValueError:
+                return False
+        return True
+
     @classmethod
     def has_map_or_list_attributes(cls):
         for attr_value in cls._get_attributes().values():

pynamodb/tests/test_model.py

@@ -3619,3 +3619,40 @@ def test_subclassed_map_attribute_with_map_attribute_member_with_initialized_ins
         self.assertEquals(actual.left.left.value, left_instance.left.value)
         self.assertEquals(actual.right.right.left.value, right_instance.right.left.value)
         self.assertEquals(actual.right.right.value, right_instance.right.value)
+
+
+class JSONUnicodeSetTestCase(TestCase):
+
+    def test_needs_unidode_set_fix_false(self):
+        test_item = {
+            'string_set_attr': {
+                'SS': ['a', 'b']
+            },
+            'map_attr': {'M': {
+                'foo': {'S': 'bar'},
+                'num': {'N': '1'},
+                'bool_type': {'BOOL': True},
+                'other_b_type': {'BOOL': False},
+                'floaty': {'N': '1.2'},
+                'listy': {'L': [{'N': '1'}, {'N': '2'}, {'N': '12345678909876543211234234324234'}]},
+                'mapy': {'M': {'baz': {'S': 'bongo'}}}
+            }}
+        }
+        assert Model._has_json_unicode_set_value(test_item) == False
+
+    def test_needs_unidode_set_fix_true(self):
+        test_item = {
+            'string_set_attr': {
+                'SS': ['a', 'b']
+            },
+            'map_attr': {'M': {
+                'foo': {'S': 'bar'},
+                'num': {'N': '1'},
+                'bool_type': {'BOOL': True},
+                'other_b_type': {'BOOL': False},
+                'floaty': {'N': '1.2'},
+                'listy': {'L': [{'N': '1'}, {'N': '2'}, {'SS': ['"a"', '"b"']}]},
+                'mapy': {'M': {'baz': {'S': 'bongo'}}}
+            }}
+        }
+        assert Model._has_json_unicode_set_value(test_item) == True