* Automatic data model documentation with <a href="https://json-schema.org/" class="external-link" target="_blank"><strong>JSON Schema</strong></a> (as OpenAPI itself is based on JSON Schema).

# `APIRouter` class

Here's the reference information for the `APIRouter` class, with all its parameters, attributes and methods.

You can import the `APIRouter` class directly from `fastapi`:

```python
from fastapi import APIRouter
```

::: fastapi.APIRouter
    options:
        members:
            - websocket
            - include_router
            - get
            - put
            - post
            - delete

* 올바른 매개변수를 가진 의존성("디펜더블") 함수를 호출합니다.
* 함수에서 결과를 받아옵니다.
* *경로 작동 함수*에 있는 매개변수에 그 결과를 할당합니다

```mermaid
graph TB

common_parameters(["common_parameters"])
read_items["/items/"]
read_users["/users/"]

common_parameters --> read_items
common_parameters --> read_users
```

이렇게 하면 공용 코드를 한번만 적어도 되며, **FastAPI**는 *경로 작동*을 위해 이에 대한 호출을 처리합니다.

!!! check "확인"

# `FastAPI` class

Here's the reference information for the `FastAPI` class, with all its parameters, attributes and methods.

You can import the `FastAPI` class directly from `fastapi`:

```python
from fastapi import FastAPI
```

::: fastapi.FastAPI
    options:
        members:
            - openapi_version
            - webhooks
            - state
            - dependency_overrides
            - openapi

!!! info
    `Form` is a class that inherits directly from `Body`.

!!! tip
    To declare form bodies, you need to use `Form` explicitly, because without it the parameters would be interpreted as query parameters or body (JSON) parameters.

## About "Form Fields"

The way HTML forms (`<form></form>`) sends the data to the server normally uses a "special" encoding for that data, it's different from JSON.

            "/users/": {
                "get": {
                    "tags": ["users"],
                    "summary": "Read Users",
                    "operationId": "read_users_users__get",
                    "parameters": [
                        {
                            "required": True,
                            "schema": {"title": "Token", "type": "string"},
                            "name": "token",

    summary: Optional[str] = None
    description: Optional[str] = None
    externalDocs: Optional[ExternalDocumentation] = None
    operationId: Optional[str] = None
    parameters: Optional[List[Union[Parameter, Reference]]] = None
    requestBody: Optional[Union[RequestBody, Reference]] = None
    # Using Any for Specification Extensions
    responses: Optional[Dict[str, Union[Response, Any]]] = None

{!> ../../../docs_src/body_nested_models/tutorial002.py!}
```

### Declare a `list` with a type parameter

To declare types that have type parameters (internal types), like `list`, `dict`, `tuple`:

* If you are in a Python version lower than 3.9, import their equivalent version from the `typing` module
* Pass the internal type(s) as "type parameters" using square brackets: `[` and `]`

In Python 3.9 it would be:

```Python

Wenn Sie **FastAPI** ein „Callable“ als Abhängigkeit übergeben, analysiert es die Parameter dieses „Callables“ und verarbeitet sie auf die gleiche Weise wie die Parameter einer *Pfadoperation-Funktion*. Einschließlich Unterabhängigkeiten.

Das gilt auch für Callables ohne Parameter. So wie es auch für *Pfadoperation-Funktionen* ohne Parameter gilt.

# Response-Header

## Verwenden Sie einen `Response`-Parameter

Sie können einen Parameter vom Typ `Response` in Ihrer *Pfadoperation-Funktion* deklarieren (wie Sie es auch für Cookies tun können).

Und dann können Sie Header in diesem *vorübergehenden* Response-Objekt festlegen.

```Python hl_lines="1  7-8"
{!../../../docs_src/response_headers/tutorial002.py!}
```