René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"[Bug]: encoding not supported for individual requestBody properties","articleBody":"### Actual Behavior\n\nOpenAPI allows specifying an `application/x-www-form-urlencoded` request body that contains individual `application/json` encoded properties, by using the [`contentType` field](https://spec.openapis.org/oas/v3.0.3#encodingContentType) of the [encoding object](https://spec.openapis.org/oas/v3.0.3#mediaTypeEncoding). The Swagger specification shows an [example](https://swagger.io/docs/specification/describing-request-body/) of this (under “Complex Serialization in Form Data”, and reproduced below). However, openapi-core ignores the `contentType` field and fails to validate a valid request against such a spec.\r\n\r\n```pytb\r\nTraceback (most recent call last):\r\n  File \"/home/anders/python/openapi-core/openapi_core/validation/decorators.py\", line 31, in wrapper\r\n    return f(*args, **kwds)\r\n  File \"/home/anders/python/openapi-core/openapi_core/validation/request/validators.py\", line 253, in _get_body\r\n    return self._get_content_value(raw_body, mimetype, content)\r\n  File \"/home/anders/python/openapi-core/openapi_core/validation/validators.py\", line 126, in _get_content_value\r\n    self._validate_schema(schema, casted)\r\n  File \"/home/anders/python/openapi-core/openapi_core/validation/validators.py\", line 102, in _validate_schema\r\n    validator.validate(value)\r\n  File \"/home/anders/python/openapi-core/openapi_core/validation/schemas/validators.py\", line 36, in validate\r\n    raise InvalidSchemaValue(value, schema_type, schema_errors=errors)\r\nopenapi_core.validation.schemas.exceptions.InvalidSchemaValue: Value {'payload': '{\"text\":\"Swagger is awesome\"}'} not valid for schema of type object: (\u003cValidationError: '\\'{\"text\":\"Swagger is awesome\"}\\' is not of type \\'object\\''\u003e,)\r\n\r\nThe above exception was the direct cause of the following exception:\r\n\r\nTraceback (most recent call last):\r\n  File \"/home/anders/python/openapi-core/post_encoding_test.py\", line 65, in \u003cmodule\u003e\r\n    validate_request(request, spec=spec)\r\n  File \"/home/anders/python/openapi-core/openapi_core/shortcuts.py\", line 305, in validate_request\r\n    validate_apicall_request(\r\n  File \"/home/anders/python/openapi-core/openapi_core/shortcuts.py\", line 379, in validate_apicall_request\r\n    return v.validate(request)\r\n  File \"/home/anders/python/openapi-core/openapi_core/validation/request/validators.py\", line 269, in validate\r\n    raise err\r\n  File \"/home/anders/python/openapi-core/openapi_core/validation/request/validators.py\", line 110, in _iter_errors\r\n    self._get_body(request.body, request.mimetype, operation)\r\n  File \"/home/anders/python/openapi-core/openapi_core/validation/decorators.py\", line 33, in wrapper\r\n    self._raise_error(exc, self.err_validate_cls, f, *args, **kwds)\r\n  File \"/home/anders/python/openapi-core/openapi_core/validation/decorators.py\", line 58, in _raise_error\r\n    raise init(**kw) from exc\r\nopenapi_core.validation.request.exceptions.InvalidRequestBody: Request body validation error\r\n```\n\n### Expected Behavior\n\nThis request should successfully validate.\n\n### Steps to Reproduce\n\n```python\r\nimport yaml\r\nfrom urllib.parse import urlencode\r\n\r\nfrom openapi_core import Spec\r\nfrom openapi_core import validate_request\r\nfrom openapi_core.testing import MockRequest\r\n\r\nSPEC = r\"\"\"\r\nopenapi: 3.0.0\r\ninfo:\r\n  version: 1.0.0\r\n  title: Slack Incoming Webhook\r\nexternalDocs:\r\n  url: https://api.slack.com/incoming-webhooks\r\n\r\nservers:\r\n  - url: https://hooks.slack.com\r\n\r\npaths:\r\n  /services/T00000000/B00000000/XXXXXXXXXXXXXXXXXXXXXXXX:\r\n    post:\r\n      summary: Post a message to Slack\r\n      requestBody:\r\n        content:\r\n\r\n          application/json:\r\n            schema:\r\n              $ref: '#/components/schemas/Message'\r\n\r\n          application/x-www-form-urlencoded:\r\n            schema:\r\n              type: object\r\n              properties:\r\n                payload:     # \u003c--- form field that contains the JSON message\r\n                  $ref: '#/components/schemas/Message'\r\n            encoding:\r\n              payload:\r\n                contentType: application/json\r\n\r\n      responses:\r\n        '200':\r\n          description: OK\r\n\r\ncomponents:\r\n  schemas:\r\n    Message:\r\n      title: A Slack message\r\n      type: object\r\n      properties:\r\n        text:\r\n          type: string\r\n          description: Message text\r\n      required:\r\n        - text\r\n\"\"\"\r\n\r\nspec = Spec.from_dict(yaml.safe_load(SPEC))\r\nrequest = MockRequest(\r\n    \"https://hooks.slack.com/\",\r\n    \"post\",\r\n    \"/services/T00000000/B00000000/XXXXXXXXXXXXXXXXXXXXXXXX\",\r\n    data=urlencode({\"payload\": '{\"text\":\"Swagger is awesome\"}'}),\r\n    mimetype=\"application/x-www-form-urlencoded\",\r\n)\r\nvalidate_request(request, spec=spec)\r\n```\n\n### OpenAPI Core Version\n\n0.18.0\n\n### OpenAPI Core Integration\n\nnone\n\n### Affected Area(s)\n\n_No response_\n\n### References\n\n_No response_\n\n### Anything else we need to know?\n\n_No response_\n\n### Would you like to implement a fix?\n\nNone","author":{"url":"https://github.com/andersk","@type":"Person","name":"andersk"},"datePublished":"2023-08-10T00:38:34.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":1},"url":"https://github.com/642/openapi-core/issues/642"}