fix(pydantic): fix pydantic JSON schema generation for FastAPI/OpenAPI#84
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akhundMurad merged 1 commit intoakhundMurad:mainfrom Jan 28, 2026
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This resolves #83
When using
TypeIDFieldin Pydantic models with FastAPI, accessing the/openapi.jsonendpoint or Swagger UI (/docs) would fail with:At first this appeared to be caused by a bug when calling
model_json_schema()on models. The first fix involved adding a missingjson_schema_input_schemaparameter to theno_info_plain_validator_functioncall in__get_pydantic_core_schema__. This resolved the error when callingmodel_json_schema()directly, but the swagger docs still wouldn't generate when using in FastAPI.The second issue was that the
__get_pydantic_json_schema__method passed the entire validator function schema to the handler instead of just thejson_schema_input_schema. Adding this fix resolved the FastAPI OpenAPI spec generation.I also added two tests, one for each of these fixes.
As a side note, I just noticed when opening the PR that my auto-formatting config resorted your imports in the test file. Sorry for not noticing that before committing. I can revert if needed.