{* ../../docs_src/events/tutorial002.py hl[6] *}

Here, the `shutdown` event handler function will write a text line `"Application shutdown"` to a file `log.txt`.

/// info

In the `open()` function, the `mode="a"` means "append", so, the line will be added after whatever is on that file, without overwriting the previous contents.

///

/// tip

The `name="static"` gives it a name that can be used internally by **FastAPI**.

All these parameters can be different than "`static`", adjust them with the needs and specific details of your own application.

## More info

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": {
            "/": {
                "post": {
                    "summary": "Main Route",
                    "operationId": "main_route__post",

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": {
                    "responses": {
                        "200": {

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

使いたい `Response` クラス (サブクラス) をインポートし、 *path operationデコレータ* に宣言します。

```Python hl_lines="2  7"
{!../../docs_src/custom_response/tutorial001b.py!}
```

/// info | "情報"

パラメータ `response_class` は、レスポンスの「メディアタイプ」を定義するために利用することもできます。

この場合、HTTPヘッダー `Content-Type` には `application/json` がセットされます。

そして、OpenAPIにはそのようにドキュメントされます。

///

/// tip | "豆知識"

        return indexFromQueryLog(new QueryLog[] { queryLog });
    }

    public SuggestIndexResponse indexFromQueryLog(final QueryLog[] queryLogs) {
        if (logger.isInfoEnabled()) {
            logger.info("Index from querylog. num: {}", queryLogs.length);
        }
        try {
            final long start = System.currentTimeMillis();
            final Stream<QueryLog> stream = Stream.of(queryLogs);

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": "ChimichangApp",
            "summary": "Deadpool's favorite app. Nuff said.",

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": {
            "/users/me": {
                "get": {
                    "responses": {
                        "200": {

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": {
            "/users/me": {
                "get": {
                    "responses": {
                        "200": {