Strange exception, saying that error in response model's types, but referencing request model #5885
Description
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Example Code
# Request model
from typing import Optional
from pydantic import BaseModel
class EditProductRequestBody(BaseModel):
marketId: int
name: Optional[str]
price: Optional[str]
leftover: Optional[int]
class Config:
arbitrary_types_allowed = True# Endpoint, which throws the exception
@app.post("/editProduct")
async def edit_product(body: EditProductRequestBody) -> Response:
...
return JSONResponse(content={"message": "success"})# Endpoint, which lays earlier, but don't throws the exception
@app.post("/uploadImage")
async def upload_image(photo: UploadFile) -> Response:
...
return JSONResponse(content={"photo": "photoId"})Description
I have a simple endpoint, which should get a model with data from body and return a json with status. But on startup it throws the exception:
Unlike #5861, it triggers to request model, but tells about invalid response
Traceback (most recent call last):
File "pydantic/validators.py", line 751, in pydantic.validators.find_validators
TypeError: issubclass() arg 1 must be a class
During handling of the above exception, another exception occurred:
Traceback (most recent call last):
File "/code/.venv/lib/python3.10/site-packages/fastapi/utils.py", line 88, in create_response_field
return response_field(field_info=field_info)
File "pydantic/fields.py", line 436, in pydantic.fields.ModelField.__init__
File "pydantic/fields.py", line 557, in pydantic.fields.ModelField.prepare
File "pydantic/fields.py", line 831, in pydantic.fields.ModelField.populate_validators
File "pydantic/validators.py", line 760, in find_validators
RuntimeError: error checking inheritance of <module 'request_bodies.EditProductRequestBody' from '/app/./request_bodies/EditProductRequestBody.py'> (type: module)
During handling of the above exception, another exception occurred:
Traceback (most recent call last):
File "/code/.venv/bin/uvicorn", line 8, in <module>
sys.exit(main())
File "/code/.venv/lib/python3.10/site-packages/click/core.py", line 1130, in __call__
return self.main(*args, **kwargs)
File "/code/.venv/lib/python3.10/site-packages/click/core.py", line 1055, in main
rv = self.invoke(ctx)
File "/code/.venv/lib/python3.10/site-packages/click/core.py", line 1404, in invoke
return ctx.invoke(self.callback, **ctx.params)
File "/code/.venv/lib/python3.10/site-packages/click/core.py", line 760, in invoke
return __callback(*args, **kwargs)
File "/code/.venv/lib/python3.10/site-packages/uvicorn/main.py", line 404, in main
run(
File "/code/.venv/lib/python3.10/site-packages/uvicorn/main.py", line 569, in run
server.run()
File "/code/.venv/lib/python3.10/site-packages/uvicorn/server.py", line 60, in run
return asyncio.run(self.serve(sockets=sockets))
File "/usr/local/lib/python3.10/asyncio/runners.py", line 44, in run
return loop.run_until_complete(main)
File "/usr/local/lib/python3.10/asyncio/base_events.py", line 649, in run_until_complete
return future.result()
File "/code/.venv/lib/python3.10/site-packages/uvicorn/server.py", line 67, in serve
config.load()
File "/code/.venv/lib/python3.10/site-packages/uvicorn/config.py", line 477, in load
self.loaded_app = import_from_string(self.app)
File "/code/.venv/lib/python3.10/site-packages/uvicorn/importer.py", line 21, in import_from_string
module = importlib.import_module(module_str)
File "/usr/local/lib/python3.10/importlib/__init__.py", line 126, in import_module
return _bootstrap._gcd_import(name[level:], package, level)
File "<frozen importlib._bootstrap>", line 1050, in _gcd_import
File "<frozen importlib._bootstrap>", line 1027, in _find_and_load
File "<frozen importlib._bootstrap>", line 1006, in _find_and_load_unlocked
File "<frozen importlib._bootstrap>", line 688, in _load_unlocked
File "<frozen importlib._bootstrap_external>", line 883, in exec_module
File "<frozen importlib._bootstrap>", line 241, in _call_with_frames_removed
File "/app/./main.py", line 25, in <module>
async def edit_product(body: EditProductRequestBody) -> Response:
File "/code/.venv/lib/python3.10/site-packages/fastapi/routing.py", line 630, in decorator
self.add_api_route(
File "/code/.venv/lib/python3.10/site-packages/fastapi/routing.py", line 569, in add_api_route
route = route_class(
File "/code/.venv/lib/python3.10/site-packages/fastapi/routing.py", line 438, in __init__
self.dependant = get_dependant(path=self.path_format, call=self.endpoint)
File "/code/.venv/lib/python3.10/site-packages/fastapi/dependencies/utils.py", line 299, in get_dependant
param_field = get_param_field(
File "/code/.venv/lib/python3.10/site-packages/fastapi/dependencies/utils.py", line 393, in get_param_field
field = create_response_field(
File "/code/.venv/lib/python3.10/site-packages/fastapi/utils.py", line 90, in create_response_field
raise fastapi.exceptions.FastAPIError(
fastapi.exceptions.FastAPIError: Invalid args for response field! Hint: check that <module 'request_bodies.EditProductRequestBody' from '/app/./request_bodies/EditProductRequestBody.py'> is a valid pydantic field type
Operating System
Other
Operating System Details
Linux (in docker)
Windows 11 (natively)
FastAPI Version
0.85, 0.87, 0.88, 0.89.1
Python Version
3.10, 3.11
Additional Context
No response