How to pass a request object as optional to a function in fastAPI?

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Example Code

from fastapi import FastAPI,Query
from starlette.requests import Request
from typing import Optional,
app = FastAPI()
@app.api_route("/endpoint/v1/{my_id}", methods=["GET", "POST", "DELETE"])
async def myFunction(request: Request, my_id: Optional[str] = None, request_type: Optional[str] = None):
#function body
                                                             ):

Description

In the above code, I could able to handle the routing and could able to access the function - myFunction as

import requests
requests.get('http://localhost:7008/endpoint/v1/'),

Then I tried to call the function directly(without routing) as

myFunction()

But it shows the error like

TypeError: myFunction() missing 1 required positional argument: 'request'

Now I have to doubts 1 - How to call a fastAPI function directly (without routing) 2 - How to put the request object parameter as optional in fastAPI function

Operating System

Linux

Operating System Details

No response

FastAPI Version

fastapi==0.75.0

Python Version

3.6.9

Additional Context

No response

[accelleon]

@pradeepdev-1995 It seems as though the issue with Optional[Request] is that Request isn’t a viable type for pydantic. Pydantic is pretty baked into FastAPI.

This is the actual exception that is being masked by FastAPI’s

  File "pydantic/main.py", line 204, in pydantic.main.ModelMetaclass.__new__
  File "pydantic/fields.py", line 488, in pydantic.fields.ModelField.infer
  File "pydantic/fields.py", line 419, in pydantic.fields.ModelField.__init__
  File "pydantic/fields.py", line 539, in pydantic.fields.ModelField.prepare
  File "pydantic/fields.py", line 801, in pydantic.fields.ModelField.populate_validators
  File "pydantic/validators.py", line 723, in find_validators
RuntimeError: no validator found for <class 'starlette.requests.Request'>, see `arbitrary_types_allowed` in Config

FastAPI is bypassing that function call for dependencies and default parameters such as the type Request. You’re gonna have to not declare the field as Optional[] and instead just pass it None. If you’re using mypy or type checking in your IDE and want to rid yourself of the error you can use type: ignore:

import starlette
@app.api_route("/endpoint/v1/{my_id}", methods=["GET", "POST", "DELETE"])
async def myFunction(request : starlette.requests.Request = None, my_id: Optional[str] = None, request_type: Optional[str] = None):  # type: ignore

[pradeepdev-1995]

@accelleon Thank you. The above solution solved my issue.