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

app = FastAPI()


@app.exception_handler(RequestValidationError)
async def validation_exception_handler(request: Request, exc: RequestValidationError):
    return JSONResponse(
        status_code=422,

If you want to catch exceptions and create a custom response based on that, create a [Custom Exception Handler](../handling-errors.md#install-custom-exception-handlers){.internal-link target=_blank}.

## Dependencies with `yield` and `except` { #dependencies-with-yield-and-except }

         * @param request the request data
         * @param exceptionList the list of exceptions that occurred during retries
         */
        void onRequestEnd(FaultTolerantClient client, RequestData request, List<Exception> exceptionList);

        /**
         * Called when an exception occurs during a request attempt.
         *
         * @param client the fault-tolerant client

                            assertNotNull(name);
                            assertTrue(name.startsWith("thread"));
                        }
                    } catch (Exception e) {
                        synchronized (exceptions) {
                            exceptions.add(e);
                        }
                    } finally {
                        endLatch.countDown();
                    }
                }

from collections.abc import Callable
from typing import Annotated

from fastapi import Body, FastAPI, HTTPException, Request, Response
from fastapi.exceptions import RequestValidationError
from fastapi.routing import APIRoute


class ValidationErrorLoggingRoute(APIRoute):
    def get_route_handler(self) -> Callable:
        original_route_handler = super().get_route_handler()

        async def custom_route_handler(request: Request) -> Response:

import pytest
from fastapi import FastAPI
from fastapi.exceptions import FastAPIError


class NonPydanticModel:
    pass


def test_invalid_response_model_raises():
    with pytest.raises(FastAPIError):
        app = FastAPI()

        @app.get("/", response_model=NonPydanticModel)
        def read_root():
            pass  # pragma: nocover


def test_invalid_response_model_sub_type_raises():

{* ../../docs_src/handling_errors/tutorial002_py39.py hl[14] *}

## Установка пользовательских обработчиков исключений { #install-custom-exception-handlers }

Вы можете добавить пользовательские обработчики исключений с помощью <a href="https://www.starlette.dev/exceptions/" class="external-link" target="_blank">тех же утилит обработки исключений из Starlette</a>.

import importlib
from types import ModuleType

import pytest
from fastapi.exceptions import FastAPIError
from fastapi.testclient import TestClient


@pytest.fixture(
    name="mod",
    params=[
        pytest.param("tutorial008c_py39"),
        pytest.param("tutorial008c_an_py39"),
    ],
)
def get_mod(request: pytest.FixtureRequest):
    mod = importlib.import_module(f"docs_src.dependencies.{request.param}")

    return mod

from fastapi import Depends, FastAPI, HTTPException
from fastapi.exceptions import RequestValidationError
from fastapi.testclient import TestClient
from starlette.responses import JSONResponse


def http_exception_handler(request, exception):
    return JSONResponse({"exception": "http-exception"})


def request_validation_exception_handler(request, exception):
    return JSONResponse({"exception": "request-validation"})

 * either express or implied. See the License for the specific language
 * governing permissions and limitations under the License.
 */
package org.codelibs.fess.exception;

/**
 * This exception is thrown when a storage-related error occurs.
 * It can be used to wrap underlying storage exceptions, providing a
 * consistent error handling mechanism for storage operations.
 */
public class StorageException extends FessSystemException {