/// note | Заметка

Этот функционал доступен начиная с версии FastAPI `0.113.0`. 🤓

///

## Pydantic-модели для форм { #pydantic-models-for-forms }

Вам просто нужно объявить **Pydantic-модель** с полями, которые вы хотите получить как **поля формы**, а затем объявить параметр как `Form`:

{* ../../docs_src/request_form_models/tutorial001_an_py39.py hl[9:11,15] *}

# 子应用 - 挂载

如果需要两个独立的 FastAPI 应用，拥有各自独立的 OpenAPI 与文档，则需设置一个主应用，并**挂载**一个（或多个）子应用。

## 挂载 **FastAPI** 应用

**挂载**是指在特定路径中添加完全**独立**的应用，然后在该路径下使用*路径操作*声明的子应用处理所有事务。

### 顶层应用

首先，创建主（顶层）**FastAPI** 应用及其*路径操作*：

{* ../../docs_src/sub_applications/tutorial001.py hl[3,6:8] *}

### 子应用

接下来，创建子应用及其*路径操作*。

子应用只是另一个标准 FastAPI 应用，但这个应用是被**挂载**的应用：

{* ../../docs_src/sub_applications/tutorial001.py hl[11,14:16] *}

from fastapi import FastAPI, Request, WebSocket
from fastapi.exceptions import (
    RequestValidationError,
    ResponseValidationError,
    WebSocketRequestValidationError,
)
from fastapi.testclient import TestClient
from pydantic import BaseModel


class Item(BaseModel):
    id: int
    name: str


class ExceptionCapture:
    def __init__(self):
        self.exception = None

    def capture(self, exc):

You have already seen how to test your **FastAPI** applications using the provided `TestClient`. Up to now, you have only seen how to write synchronous tests, without using `async` functions.

{* ../../docs_src/path_operation_configuration/tutorial001.py hl[3,17] *}

状态码在响应中使用，并会被添加到 OpenAPI 概图。

/// note | 技术细节

也可以使用 `from starlette import status` 导入状态码。

**FastAPI** 的`fastapi.status` 和 `starlette.status` 一样，只是快捷方式。实际上，`fastapi.status` 直接继承自 Starlette。

///

## `tags` 参数

`tags` 参数的值是由 `str` 组成的 `list` （一般只有一个 `str` ），`tags` 用于为*路径操作*添加标签：

    needed for non-async code.

    Read more about it in the
    [FastAPI docs for Request Files](https://fastapi.tiangolo.com/tutorial/request-files/).

    ## Example

    ```python
    from typing import Annotated

    from fastapi import FastAPI, File, UploadFile

    app = FastAPI()


    @app.post("/files/")
    async def create_file(file: Annotated[bytes, File()]):

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

    Read more about it in the
    [FastAPI docs for Custom Response - HTML, Stream, File, others](https://fastapi.tiangolo.com/advanced/custom-response/).
    """

    def render(self, content: Any) -> bytes:
        assert ujson is not None, "ujson must be installed to use UJSONResponse"

from typing import Annotated, Any

import pytest
from fastapi import Depends, FastAPI, HTTPException
from fastapi.testclient import TestClient


class CustomError(Exception):
    pass


def catching_dep() -> Any:
    try:
        yield "s"
    except CustomError as err:
        raise HTTPException(status_code=418, detail="Session error") from err


def broken_dep() -> Any:
    yield "s"

import pytest
from fastapi import Body, Depends, FastAPI, HTTPException
from fastapi.testclient import TestClient

initial_fake_database = {"rick": "Rick Sanchez"}

fake_database = initial_fake_database.copy()

initial_state = {"except": False, "finally": False}

state = initial_state.copy()

app = FastAPI()


async def get_database():
    temp_database = fake_database.copy()
    try:
        yield temp_database

from fastapi import FastAPI
from pydantic import BaseModel, Field

app = FastAPI()


class Item(BaseModel):
    name: str = Field(examples=["Foo"])
    description: str | None = Field(default=None, examples=["A very nice Item"])
    price: float = Field(examples=[35.4])
    tax: float | None = Field(default=None, examples=[3.2])


@app.put("/items/{item_id}")
async def update_item(item_id: int, item: Item):