def iter_data():
        yield json.dumps({"is_open": session.open})

    return StreamingResponse(iter_data())


@app.get("/request-scope")
def request_scope(session: SessionRequestDep) -> Any:
    def iter_data():
        yield json.dumps({"is_open": session.open})

    return StreamingResponse(iter_data())


@app.get("/two-scopes")
def get_stream_session(

from starlette.responses import RedirectResponse as RedirectResponse  # noqa
from starlette.responses import Response as Response  # noqa
from starlette.responses import StreamingResponse as StreamingResponse  # noqa

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


try:
    import orjson
except ImportError:  # pragma: nocover

```python
from fastapi.responses import (
    FileResponse,
    HTMLResponse,
    JSONResponse,
    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:

from fastapi import FastAPI
from fastapi.responses import StreamingResponse

some_file_path = "large-video-file.mp4"
app = FastAPI()


@app.get("/")
def main():
    def iterfile():  # (1)
        with open(some_file_path, mode="rb") as file_like:  # (2)
            yield from file_like  # (3)

def get_stream_simple(session: SessionDep) -> Any:
    def iter_data():
        yield from ["x", "y", "z"]

    return StreamingResponse(iter_data())


@app.get("/stream-session")
def get_stream_session(session: SessionDep) -> Any:
    def iter_data():
        yield from session

    return StreamingResponse(iter_data())


@app.get("/broken-session-data")
def get_broken_session_data(session: BrokenSessionDep) -> Any:

from fastapi import FastAPI
from fastapi.responses import StreamingResponse

app = FastAPI()


async def fake_video_streamer():
    for i in range(10):
        yield b"some fake video bytes"


@app.get("/")
async def main():

import time
from typing import Annotated

from fastapi import Depends, FastAPI, HTTPException
from fastapi.responses import StreamingResponse
from sqlmodel import Field, Session, SQLModel, create_engine

engine = create_engine("postgresql+psycopg://postgres:postgres@localhost/db")


class User(SQLModel, table=True):
    id: int | None = Field(default=None, primary_key=True)
    name: str


app = FastAPI()


def get_session():

Подробнее читайте в документации: [Зависимости с `yield` — раннее завершение и `scope`](../tutorial/dependencies/dependencies-with-yield.md#early-exit-and-scope).

### Зависимости с `yield` и `StreamingResponse`, технические детали { #dependencies-with-yield-and-streamingresponse-technical-details }

До FastAPI 0.118.0, если вы использовали зависимость с `yield`, код после `yield` выполнялся после возврата из *функции-обработчика пути*, но прямо перед отправкой ответа.

import time
from typing import Annotated

from fastapi import Depends, FastAPI, HTTPException
from fastapi.responses import StreamingResponse
from sqlmodel import Field, Session, SQLModel, create_engine

engine = create_engine("postgresql+psycopg://postgres:postgres@localhost/db")


class User(SQLModel, table=True):
    id: int | None = Field(default=None, primary_key=True)
    name: str


app = FastAPI()


def get_session():

{* ../../docs_src/custom_response/tutorial006c_py39.py hl[2,7,9] *}

### `StreamingResponse` { #streamingresponse }

Toma un generador `async` o un generador/iterador normal y transmite el cuerpo del response.

{* ../../docs_src/custom_response/tutorial007_py39.py hl[2,14] *}

#### Usando `StreamingResponse` con objetos similares a archivos { #using-streamingresponse-with-file-like-objects }