* Add a **JSON Schema** for the response, in the OpenAPI *path operation*.
    * This will be used by the **automatic docs**.
    * It will also be used by automatic client code generation tools.

But most importantly:

* It will **limit and filter** the output data to what is defined in the return type.
    * This is particularly important for **security**, we'll see more of that below.

## `response_model` Parameter

def test_body_float(client: TestClient):
    response = client.post("/items/", json={"name": "Foo", "price": 50.5})
    assert response.status_code == 200
    assert response.json() == {
        "name": "Foo",
        "price": 50.5,
        "description": None,
        "tax": None,
    }


@needs_py310
def test_post_with_str_float(client: TestClient):
    response = client.post("/items/", json={"name": "Foo", "price": "50.5"})

def test_body_float(client: TestClient):
    response = client.post("/items/", json={"name": "Foo", "price": 50.5})
    assert response.status_code == 200
    assert response.json() == {
        "name": "Foo",
        "price": 50.5,
        "description": None,
        "tax": None,
    }


def test_post_with_str_float(client: TestClient):
    response = client.post("/items/", json={"name": "Foo", "price": "50.5"})

    client = TestClient(app)
    return client


def test_post_body_form(client: TestClient):
    response = client.post("/login/", data={"username": "Foo", "password": "secret"})
    assert response.status_code == 200
    assert response.json() == {"username": "Foo"}


def test_post_body_form_no_password(client: TestClient):
    response = client.post("/login/", data={"username": "Foo"})
    assert response.status_code == 422

from dirty_equals import IsDict
from fastapi.testclient import TestClient

from docs_src.handling_errors.tutorial005 import app

client = TestClient(app)


def test_post_validation_error():
    response = client.post("/items/", json={"title": "towel", "size": "XL"})
    assert response.status_code == 422, response.text
    assert response.json() == IsDict(
        {
            "detail": [
                {

<font color="#4E9A06">INFO</font>:     Application startup complete.
<font color="#4E9A06">INFO</font>:     Uvicorn running on <b>http://0.0.0.0:8000</b> (Press CTRL+C to quit)
```

</div>

That would work for most of the cases. 😎

You could use that command for example to start your **FastAPI** app in a container, in a server, etc.

## ASGI Servers

Let's go a little deeper into the details.

    data = {"username": username, "password": password}
    if scope:
        data["scope"] = scope
    response = client.post("/token", data=data)
    content = response.json()
    access_token = content.get("access_token")
    return access_token


def test_login():
    response = client.post("/token", data={"username": "johndoe", "password": "secret"})
    assert response.status_code == 200, response.text

def test_create_item_bad_token():
    response = client.post(
        "/items/",
        headers={"X-Token": "hailhydra"},
        json={"id": "bazz", "title": "Bazz", "description": "Drop the bazz"},
    )
    assert response.status_code == 400
    assert response.json() == {"detail": "Invalid X-Token header"}


def test_create_existing_item():
    response = client.post(
        "/items/",

따라서 섹션

```Python
    uvicorn.run(app, host="0.0.0.0", port=8000)
```

이 실행됩니다.

---

해당 모듈(파일)을 가져오면 이런 일이 발생하지 않습니다

그래서 다음과 같은 다른 파일 `importer.py`가 있는 경우:

```Python
from myapp import app

# Some more code
```

이 경우 `myapp.py` 내부의 자동 변수에는 값이 `"__main__"`인 변수 `__name__`이 없습니다.

따라서 다음 행

```Python
    uvicorn.run(app, host="0.0.0.0", port=8000)
```

은 실행되지 않습니다.

При создании API, "путь" является основным способом разделения "задач" и "ресурсов".

#### Операция (operation)

"Операция" это один из "методов" HTTP.

Таких, как:

* `POST`
* `GET`
* `PUT`
* `DELETE`

...и более экзотических:

* `OPTIONS`
* `HEAD`
* `PATCH`
* `TRACE`