Add NullUnmarshaller

The value 'null' is allowed in OpenAPI 3.1.

Signed-off-by: Stephen Finucane <stephen@that.guru>

Author: stephenfin

openapi_core/unmarshalling/schemas/factories.py

@@ -30,6 +30,7 @@
 from openapi_core.unmarshalling.schemas.unmarshallers import (
     IntegerUnmarshaller,
 )
+from openapi_core.unmarshalling.schemas.unmarshallers import NullUnmarshaller
 from openapi_core.unmarshalling.schemas.unmarshallers import NumberUnmarshaller
 from openapi_core.unmarshalling.schemas.unmarshallers import ObjectUnmarshaller
 from openapi_core.unmarshalling.schemas.unmarshallers import StringUnmarshaller
@@ -45,6 +46,7 @@ class SchemaUnmarshallersFactory:
         "boolean": BooleanUnmarshaller,
         "array": ArrayUnmarshaller,
         "object": ObjectUnmarshaller,
+        "null": NullUnmarshaller,
         "any": AnyUnmarshaller,
     }
 

openapi_core/unmarshalling/schemas/unmarshallers.py

@@ -2,7 +2,6 @@
 from functools import partial
 from typing import TYPE_CHECKING
 from typing import Any
-from typing import Dict
 from typing import Iterable
 from typing import List
 from typing import Optional
@@ -12,6 +11,7 @@
 from jsonschema._types import is_array
 from jsonschema._types import is_bool
 from jsonschema._types import is_integer
+from jsonschema._types import is_null
 from jsonschema._types import is_number
 from jsonschema._types import is_object
 from jsonschema.protocols import Validator
@@ -159,6 +159,13 @@ class BooleanUnmarshaller(BaseSchemaUnmarshaller):
     }
 
 
+class NullUnmarshaller(BaseSchemaUnmarshaller):
+
+    FORMATTERS: FormattersDict = {
+        None: Formatter.from_callables(partial(is_null, None), None),
+    }
+
+
 class ComplexUnmarshaller(BaseSchemaUnmarshaller):
     def __init__(
         self,