}

// KV contains a key and value pair parsed from a decoded object
type KV struct {
	Key   string      `json:"key"`
	Value interface{} `json:"value"`
}

// KVS - represents key values in an JSON object
type KVS []KV

// MarshalJSON - implements converting a KVS datastructure into a JSON
// object with multiple keys and values.
func (kvs KVS) MarshalJSON() ([]byte, error) {
	b := new(bytes.Buffer)

#### 数据「模式」

「模式」这个术语也可能指的是某些数据比如 JSON 的结构。

在这种情况下，它可以表示 JSON 的属性及其具有的数据类型，等等。

#### OpenAPI 和 JSON Schema

OpenAPI 为你的 API 定义 API 模式。该模式中包含了你的 API 发送和接收的数据的定义（或称为「模式」），这些定义通过 JSON 数据模式标准 **JSON Schema** 所生成。

#### 查看 `openapi.json`

如果你对原始的 OpenAPI 模式长什么样子感到好奇，其实它只是一个自动生成的包含了所有 API 描述的 JSON。

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

Mas se o cliente faz uma requisição para `http://example.com/items/bar` (ou seja, um não existente `item_id "bar"`), esse cliente receberá um HTTP status code 404 (o erro "não encontrado" — *not found error*), e uma resposta JSON:

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

/// tip | "Dica"

    assert len(response.content)
    os.remove("./image.png")


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

	return ARN{TargetID: tid, region: region}
}

// MarshalJSON - encodes to JSON data.
func (tid TargetID) MarshalJSON() ([]byte, error) {
	return json.Marshal(tid.String())
}

// UnmarshalJSON - decodes JSON data.
func (tid *TargetID) UnmarshalJSON(data []byte) error {
	var s string
	if err := json.Unmarshal(data, &s); err != nil {
		return err
	}

	targetID, err := parseTargetID(s)

@app.get("/a/{id}")
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() == {
        "openapi": "3.1.0",
        "info": {"title": "FastAPI", "version": "0.1.0"},
        "paths": {
            "/a/{id}": {
                "get": {

def test_get_api_route():
    response = client.get("/")
    assert response.status_code == 200, response.text
    assert response.json() == {"c": {}, "d": {"a": {}}}


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

    assert response.status_code == 200, response.text
    assert response.json() == "a"


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


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


def test_d():
    response = client.get("/d")

    response = client.get(path)
    assert response.status_code == expected_status
    assert response.json() == expected_response


@needs_py310
def test_openapi_schema(client: TestClient):
    response = client.get("/openapi.json")
    assert response.status_code == 200, response.text
    assert response.json() == {
        "openapi": "3.1.0",
        "info": {"title": "FastAPI", "version": "0.1.0"},
        "paths": {

Функция не возвращает большой `str`, содержащий данные в формате JSON (в виде строки). Она возвращает стандартную структуру данных Python (например, `dict`) со значениями и подзначениями, которые совместимы с JSON.

/// note | "Технические детали"