from fastapi.exceptions import RequestValidationError
from fastapi.responses import PlainTextResponse
from starlette.exceptions import HTTPException as StarletteHTTPException

app = FastAPI()


@app.exception_handler(StarletteHTTPException)
async def http_exception_handler(request, exc):
    return PlainTextResponse(str(exc.detail), status_code=exc.status_code)


@app.exception_handler(RequestValidationError)

    http_exception_handler,
    request_validation_exception_handler,
)
from fastapi.exceptions import RequestValidationError
from starlette.exceptions import HTTPException as StarletteHTTPException

app = FastAPI()


@app.exception_handler(StarletteHTTPException)
async def custom_http_exception_handler(request, exc):
    print(f"OMG! An HTTP error!: {repr(exc)}")
    return await http_exception_handler(request, exc)

from pydantic import BaseModel, create_model
from starlette.exceptions import HTTPException as StarletteHTTPException
from starlette.exceptions import WebSocketException as StarletteWebSocketException
from typing_extensions import Annotated, Doc


class HTTPException(StarletteHTTPException):
    """
    An HTTP exception you can raise in your own code to show errors to the client.

from fastapi import FastAPI, HTTPException
from fastapi.testclient import TestClient
from starlette.exceptions import HTTPException as StarletteHTTPException

app = FastAPI()

items = {"foo": "The Foo Wrestlers"}


@app.get("/items/{item_id}")
async def read_item(item_id: str):
    if item_id not in items:
        raise HTTPException(
            status_code=404,
            detail="Item not found",

👉 🌌, 🚥 🙆 🍕 💃 🔗 📟, ⚖️ 💃 ↔ ⚖️ 🔌 -, 🤚 💃 `HTTPException`, 👆 🐕‍🦺 🔜 💪 ✊ & 🍵 ⚫️.

👉 🖼, 💪 ✔️ 👯‍♂️ `HTTPException`Ⓜ 🎏 📟, 💃 ⚠ 📁 `StarletteHTTPException`:

```Python
from starlette.exceptions import HTTPException as StarletteHTTPException
```

### 🏤-⚙️ **FastAPI**'Ⓜ ⚠ 🐕‍🦺

🚥 👆 💚 ⚙️ ⚠ ⤴️ ⏮️ 🎏 🔢 ⚠ 🐕‍🦺 ⚪️➡️ **FastAPI**, 👆 💪 🗄 & 🏤-⚙️ 🔢 ⚠ 🐕‍🦺 ⚪️➡️ `fastapi.exception_handlers`:

In this example, to be able to have both `HTTPException`s in the same code, Starlette's exceptions is renamed to `StarletteHTTPException`:

```Python
from starlette.exceptions import HTTPException as StarletteHTTPException
```

### Reuse **FastAPI**'s exception handlers

这样做是为了，当 Starlette 的内部代码、扩展或插件触发 Starlette `HTTPException` 时，处理程序能够捕获、并处理此异常。

注意，本例代码中同时使用了这两个 `HTTPException`，此时，要把 Starlette 的 `HTTPException` 命名为 `StarletteHTTPException`：

```Python
from starlette.exceptions import HTTPException as StarletteHTTPException

```

### 复用 **FastAPI** 异常处理器

FastAPI 支持先对异常进行某些处理，然后再使用 **FastAPI** 中处理该异常的默认异常处理器。

从 `fastapi.exception_handlers` 中导入要复用的默认异常处理器：