customizer.py

from collections import defaultdict

from fastapi import FastAPI, Request
from fastapi.encoders import jsonable_encoder
from fastapi.exceptions import HTTPException, RequestValidationError
from fastapi.responses import JSONResponse


def validation_body_exception_handler(app: FastAPI) -> callable:
    @app.exception_handler(RequestValidationError)
    async def validation_exception_handler(
        request: Request, exc: RequestValidationError
    ) -> JSONResponse:
        try:
            raw_err = exc.raw_errors
            error_wrapper = raw_err[0]
            validation_error = error_wrapper.exc

            overwritten_errors = validation_error.errors()

            resp = {"code": 422, "msg": "Unprocessable Entity", "errors": {}}

            for e in overwritten_errors:
                resp["errors"][e["loc"][0]] = e["msg"]

            return JSONResponse(status_code=422, content=jsonable_encoder(resp))
        except AttributeError as e:
            rearranged_errors = defaultdict(list)
            for pydantic_error in exc.errors():
                loc, msg = pydantic_error["loc"], pydantic_error["msg"]
                filtered_loc = loc[1:] if loc[0] in ("body", "query", "path") else loc
                field_string = ".".join(filtered_loc)  # nested fields with dot-notation
                rearranged_errors[field_string].append(msg)

            resp = {"code": 422, "msg": "Unprocessable Entity", "errors": {}}

            for k, v in rearranged_errors.items():
                if k == "" or v == "":
                    resp = {
                        "code": 422,
                        "msg": "Please fill all the field",
                    }

                    return JSONResponse(status_code=422, content=jsonable_encoder(resp))

                resp["errors"][k] = v[0]

            return JSONResponse(status_code=422, content=jsonable_encoder(resp))
        except Exception as e:
            print(e)

            resp = {
                "code": 422,
                "msg": "Please fill all the field",
            }

            return JSONResponse(status_code=422, content=jsonable_encoder(resp))

    return validation_exception_handler


def http_customize_handler(app: FastAPI) -> callable:
    @app.exception_handler(HTTPException)
    async def http_exception_handler(
        request: Request, exc: HTTPException
    ) -> JSONResponse:
        resp = {"code": exc.status_code, "msg": exc.detail}

        return JSONResponse(status_code=exc.status_code, content=jsonable_encoder(resp))

    return http_exception_handler