Spec validation

By default, spec dict is validated on spec creation time. Disabling the validation can improve the performance.

from openapi_core import create_spec

spec = create_spec(spec_dict, validate_spec=False)


Pass custom defined media type deserializers dictionary with supported mimetypes as a key to RequestValidator or ResponseValidator constructor:

def protobuf_deserializer(message):
    feature = route_guide_pb2.Feature()
    return feature

custom_media_type_deserializers = {
    'application/protobuf': protobuf_deserializer,

validator = ResponseValidator(
    spec, custom_media_type_deserializers=custom_media_type_deserializers)

result = validator.validate(request, response)


OpenAPI defines a format keyword that hints at how a value should be interpreted, e.g. a string with the type date should conform to the RFC 3339 date format.

Openapi-core comes with a set of built-in formatters, but it’s also possible to add support for custom formatters for RequestValidator and ResponseValidator.

Here’s how you could add support for a usdate format that handles dates of the form MM/DD/YYYY:

 from datetime import datetime
 import re

 class USDateFormatter:
     def validate(self, value) -> bool:
         return bool(re.match(r"^\d{1,2}/\d{1,2}/\d{4}$", value))

     def unmarshal(self, value):
         return datetime.strptime(value, "%m/%d/%y").date

custom_formatters = {
    'usdate': USDateFormatter(),

validator = ResponseValidator(spec, custom_formatters=custom_formatters)

result = validator.validate(request, response)