support null type in queries

Author: gridnevvvit

CHANGELOG.md

@@ -1,6 +1,7 @@
 ## 2.2.0 ##
 
 * allow to refer endpoints by node id
+* support null type in queries
 
 ## 2.1.0 ##
 

ydb/convert.py

@@ -256,10 +256,15 @@ def _primitive_type_to_native(type_pb):
     return _primitive_type_by_id.get(type_pb.type_id)
 
 
+def _null_type_factory(type_pb):
+    return types.NullType()
+
+
 _type_to_native_map = {
     "optional_type": _optional_type_to_native,
     "type_id": _primitive_type_to_native,
     "decimal_type": _decimal_type_to_native,
+    "null_type": _null_type_factory,
 }
 
 

ydb/types.py

@@ -7,6 +7,7 @@
 from datetime import date, datetime
 import uuid
 import struct
+from google.protobuf import struct_pb2
 
 
 if six.PY3:
@@ -214,6 +215,20 @@ def __str__(self):
         return "Decimal(%d,%d)" % (self._precision, self._scale)
 
 
+class NullType(AbstractTypeBuilder):
+    __slots__ = ("_repr", "_proto")
+
+    def __init__(self):
+        self._proto = _apis.ydb_value.Type(null_type=struct_pb2.NULL_VALUE)
+
+    @property
+    def proto(self):
+        return self._proto
+
+    def __str__(self):
+        return "NullType"
+
+
 class OptionalType(AbstractTypeBuilder):
     __slots__ = ("_repr", "_proto", "_item")