import ujson
except ImportError:  # pragma: nocover
    ujson = None  # type: ignore


try:
    import orjson
except ImportError:  # pragma: nocover
    orjson = None  # type: ignore


class UJSONResponse(JSONResponse):
    """
    JSON response using the high-performance ujson library to serialize data to JSON.

    Read more about it in the

    ORJSONResponse,
    PlainTextResponse,
    RedirectResponse,
    Response,
    StreamingResponse,
    UJSONResponse,
)
```

## FastAPI Responses

There are a couple of custom FastAPI response classes, you can use them to optimize JSON performance.

::: fastapi.responses.UJSONResponse
    options:
        members:
            - charset
            - status_code
            - media_type

from fastapi import FastAPI
from fastapi.responses import UJSONResponse

app = FastAPI()


@app.get("/items/", response_class=UJSONResponse)
async def read_items():

如上文所述，这是 **FastAPI** 中使用的默认响应。

### `ORJSONResponse`

如上文所述，`ORJSONResponse` 是一个使用 <a href="https://github.com/ijl/orjson" class="external-link" target="_blank">`orjson`</a> 的快速的可选 JSON 响应。


### `UJSONResponse`

`UJSONResponse` 是一个使用 <a href="https://github.com/ultrajson/ultrajson" class="external-link" target="_blank">`ujson`</a> 的可选 JSON 响应。

/// warning | "警告"

在处理某些边缘情况时，`ujson` 不如 Python 的内置实现那么谨慎。

///

しかし、*path operationデコレータ* に、使いたい `Response` を宣言することもできます。

*path operation関数* から返されるコンテンツは、その `Response` に含まれます。

そしてもし、`Response` が、`JSONResponse` や `UJSONResponse` の場合のようにJSONメディアタイプ (`application/json`) ならば、データは *path operationデコレータ* に宣言したPydantic `response_model` により自動的に変換 (もしくはフィルタ) されます。

/// note | "備考"

Der Inhalt, den Sie von Ihrer *Pfadoperation-Funktion* zurückgeben, wird in diese `Response` eingefügt.

Und wenn diese `Response` einen JSON-Medientyp (`application/json`) hat, wie es bei `JSONResponse` und `UJSONResponse` der Fall ist, werden die von Ihnen zurückgegebenen Daten automatisch mit jedem Pydantic `response_model` konvertiert (und gefiltert), das Sie im *Pfadoperation-Dekorator* deklariert haben.

/// note | "Hinweis"

The contents that you return from your *path operation function* will be put inside of that `Response`.

And if that `Response` has a JSON media type (`application/json`), like is the case with the `JSONResponse` and `UJSONResponse`, the data you return will be automatically converted (and filtered) with any Pydantic `response_model` that you declared in the *path operation decorator*.

/// note

Os conteúdos que você retorna em sua *função de operador de rota* serão colocados dentro dessa `Response`.

E se a `Response` tiver um media type JSON (`application/json`), como é o caso com `JSONResponse` e `UJSONResponse`, os dados que você retornar serão automaticamente convertidos (e filtrados) com qualquer `response_model` do Pydantic que for declarado em sua *função de operador de rota*.

/// note | Nota

✋️ 👆 💪 📣 `Response` 👈 👆 💚 ⚙️, *➡ 🛠️ 👨‍🎨*.

🎚 👈 👆 📨 ⚪️➡️ 👆 *➡ 🛠️ 🔢* 🔜 🚮 🔘 👈 `Response`.

& 🚥 👈 `Response` ✔️ 🎻 📻 🆎 (`application/json`), 💖 💼 ⏮️ `JSONResponse` & `UJSONResponse`, 💽 👆 📨 🔜 🔁 🗜 (& ⛽) ⏮️ 🙆 Pydantic `response_model` 👈 👆 📣 *➡ 🛠️ 👨‍🎨*.

/// note

🚥 👆 ⚙️ 📨 🎓 ⏮️ 🙅‍♂ 📻 🆎, FastAPI 🔜 ⌛ 👆 📨 ✔️ 🙅‍♂ 🎚, ⚫️ 🔜 🚫 📄 📨 📁 🚮 🏗 🗄 🩺.

///

    # For Starlette's SessionMiddleware, not commonly used with FastAPI
    "itsdangerous >=1.1.0",
    # For Starlette's schema generation, would not be used with FastAPI
    "pyyaml >=5.3.1",
    # For UJSONResponse
    "ujson >=4.0.1,!=4.0.2,!=4.1.0,!=4.2.0,!=4.3.0,!=5.0.0,!=5.1.0",
    # For ORJSONResponse
    "orjson >=3.2.1",
    # To validate email fields
    "email-validator >=2.0.0",
    # Uvicorn with uvloop