Fix for query method in Dynamo (hedyorg#663)

* Fix for query method in Dynamo.

* Use serializer.

e2e_tests.py

@@ -449,6 +449,7 @@ def suite (username):
         ['unshare program', 'post', '/programs/share', {}, lambda state: {'id': state ['program'] ['id'], 'public': False}, 200],
         ['delete program', 'get', lambda state: '/programs/delete/' + state ['program'] ['id'], {}, {}, 302],
         ['retrieve programs after deleting saved program', 'get', '/programs_list', {}, {}, 200, retrieveProgramsBefore],
+        ['create program before destroying account', 'post', '/programs', {}, {'code': 'print Hello world', 'name': 'Program 1', 'level': 1}, 200],
         ['destroy account', 'post', '/auth/destroy', {}, {}, 200],
         ['get programs without being logged in', 'get', '/programs', {}, {}, 302],
         # Auth: profile (programming experience)

website/dynamo.py

@@ -172,9 +172,13 @@ def get_item(self, table_name, key):
         return self._decode(result.get('Item', None))
 
     def query(self, table_name, key, reverse=False):
+        assert len(key.keys ()) == 1
+        key_field = list (key.keys ()) [0]
+        key_value = key [key_field]
         result = self.db.query(
             TableName=self.db_prefix + '-' + table_name,
-            Key = self._encode(key),
+            KeyConditionExpression = key_field + ' = :value',
+            ExpressionAttributeValues = {':value': self.SERIALIZER.serialize (key_value)},
             ScanIndexForward = not reverse)
         return list(map(self._decode, result.get('Items', [])))
 
@@ -460,4 +464,4 @@ def decode_object(obj):
         """The decoding for the encoding above."""
         if obj.get('$type') == 'set':
             return set(obj['elements'])
-        return obj
+        return obj