```JSON
{
  "item": "The Foo Wrestlers"
}
```

Mais si le client demande `http://example.com/items/bar` (un `item_id` inexistant « bar »), il recevra un code d'état HTTP 404 (l'erreur « not found ») et une réponse JSON :

```JSON
{
  "detail": "Item not found"
}
```

/// tip | Astuce

///

## About "Form Fields" { #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.

**FastAPI** will make sure to read that data from the right place instead of JSON.

/// note | Technical Details

    assert response.json() == {"username": "secret"}


def test_security_api_key_no_key():
    response = client.get("/users/me")
    assert response.status_code == 401, response.text
    assert response.json() == {"detail": "Not authenticated"}
    assert response.headers["WWW-Authenticate"] == "APIKey"


def test_openapi_schema():
    response = client.get("/openapi.json")

    assert response.status_code == 200, response.text
    assert response.json() == {"scheme": "Other", "credentials": "foobar"}


def test_security_http_base_no_credentials():
    response = client.get("/users/me")
    assert response.status_code == 401, response.text
    assert response.json() == {"detail": "Not authenticated"}
    assert response.headers["WWW-Authenticate"] == "Other"

///

## Sobre "Campos de formulario" { #about-form-fields }

La manera en que los formularios HTML (`<form></form>`) envían los datos al servidor normalmente usa una codificación "especial" para esos datos, es diferente de JSON.

**FastAPI** se encargará de leer esos datos del lugar correcto en lugar de JSON.

/// note | Detalles técnicos

And you could do this even if the data type in the request is not JSON.

For example, in this application we don't use FastAPI's integrated functionality to extract the JSON Schema from Pydantic models nor the automatic validation for JSON. In fact, we are declaring the request content type as YAML, not JSON:

{* ../../docs_src/path_operation_advanced_configuration/tutorial007_py310.py hl[15:20, 22] *}

		AES256GCM        = "AES-256-GCM-HMAC-SHA-256"
		CHACHA20POLY1305 = "ChaCha20Poly1305"
	)

	type JSON struct {
		Algorithm string `json:"aead"`
		ID        string `json:"id"`
		IV        []byte `json:"iv"`
		Nonce     []byte `json:"nonce"`
		Bytes     []byte `json:"bytes"`
	}
	var value JSON
	if err := json.Unmarshal(text, &value); err != nil {
		return ErrDecrypt
	}

```JSON
{
  "item": "The Foo Wrestlers"
}
```

但如果客户端请求 `http://example.com/items/bar`（不存在的 `item_id` `"bar"`），则会接收到 HTTP 状态码 404（“未找到”错误）及如下 JSON 响应结果：

```JSON
{
  "detail": "Item not found"
}
```

/// tip | 提示

触发 `HTTPException` 时，可以用参数 `detail` 传递任何能转换为 JSON 的值，不仅限于 `str`。

还支持传递 `dict`、`list` 等数据结构。

)
async def a(id):
    pass  # pragma: no cover


client = TestClient(app)


def test_openapi_schema():
    response = client.get("/openapi.json")
    assert response.status_code == 200, response.text
    assert response.json() == snapshot(
        {
            "openapi": "3.1.0",
            "info": {"title": "FastAPI", "version": "0.1.0"},
            "paths": {
                "/a/{id}": {

    assert response.status_code == 200, response.text
    assert response.json() == {"username": "secret"}


def test_security_api_key_no_key():
    response = client.get("/users/me")
    assert response.status_code == 200, response.text
    assert response.json() == {"msg": "Create an account first"}


def test_openapi_schema():
    response = client.get("/openapi.json")
    assert response.status_code == 200, response.text