Custom 404 Not Found Page with FastAPI

To create a custom 404 Not Found page, FastAPI offers several approaches. The appropriate method depends on your specific requirements.

Redirect on 404 Status Code

response = await call_next(request)
if response.status_code == 404:
    return RedirectResponse("https://fastapi.tiangolo.com")
else:
    return response

This middleware checks the response status code and redirects to a custom page if the code is 404.

Custom Exception Handler for 404

return RedirectResponse('https://fastapi.tiangolo.com')

A custom exception handler can be created specifically for the 404 status code. This allows for a more specific and targeted response.

Custom Error Pages Using Templates

FastAPI supports the use of templates to render custom error pages. This example creates two error pages:

404: not_found_error,
500: internal_error

}

app = FastAPI(exception_handlers=exception_handlers)

Templates are located in the 'templates' directory and can be customized to your needs.

By selecting the method that best suits your application, you can create a custom 404 Not Found page in FastAPI.