Por exemplo, vamos dizer que você deseja ter uma *operação de caminho* que permita atualizar itens, e retornar um código de status HTTP 200 "OK" quando for bem sucedido.

Mas você também deseja aceitar novos itens. E quando os itens não existiam, ele os cria, e retorna o código de status HTTP 201 "Created.

### レスポンス結果

クライアントが`http://example.com/items/foo`（`item_id` `"foo"`）をリクエストすると、HTTPステータスコードが200で、以下のJSONレスポンスが返されます:

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

しかし、クライアントが`http://example.com/items/bar`（存在しない`item_id` `"bar"`）をリクエストした場合、HTTPステータスコード404（"not found"エラー）と以下のJSONレスポンスが返されます:

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

/// tip | 豆知識

                    "message": {
                        "title": "Message",
                        "type": "string"
                    }
                }
            },
            "Item": {
                "title": "Item",
                "required": [
                    "id",
                    "value"
                ],
                "type": "object",
                "properties": {

```JSON hl_lines="22"
{
    "openapi": "3.1.0",
    "info": {
        "title": "FastAPI",
        "version": "0.1.0"
    },
    "paths": {
        "/items/": {
            "get": {
                "summary": "Read Items",
                "operationId": "read_items_items__get",
                "responses": {
                    "200": {
                        "description": "Successful Response",

                            <li class="breadcrumb-item active"><la:link href="/admin/elevateword">
                                <la:message key="labels.elevate_word_link_list"/>
                            </la:link></li>
                            <c:if test="${crudMode == 1}">
                                <li class="breadcrumb-item active"><la:message

To add a function that should be run before the application starts, declare it with the event `"startup"`:

{* ../../docs_src/events/tutorial001.py hl[8] *}

In this case, the `startup` event handler function will initialize the items "database" (just a `dict`) with some values.

You can add more than one event handler function.

And your application won't start receiving requests until all the `startup` event handlers have completed.

                                            <tbody>
                                            <c:forEach var="data" varStatus="s"
                                                       items="${webConfigItems}">
                                                <tr
                                                        data-href="${contextPath}/admin/webconfig/details/4/${f:u(data.id)}">

                            <li class="breadcrumb-item"><la:link href="/admin/crawlinginfo">
                                <la:message key="labels.crawling_info_link_top"/>
                            </la:link></li>
                            <c:if test="${crudMode == 4}">
                                <li class="breadcrumb-item active"><la:message

maven.user.conf         = ${user.home}/.m2
maven.project.conf      = ${session.rootDirectory}/.mvn

# Comma-separated list of files to include.
# Each item may be enclosed in quotes to gracefully include spaces. Items are trimmed before being loaded.
# If the first character of an item is a question mark, the load will silently fail if the file does not exist.
${includes} = ?"${maven.user.conf}/maven-system.properties", \

{* ../../docs_src/query_param_models/tutorial002_an_py310.py hl[10] *}

如果客戶端嘗試在**查詢參數**中發送一些**額外的**資料，他們將會收到一個**錯誤**回應。

例如，如果客戶端嘗試發送一個值為 `plumbus` 的 `tool` 查詢參數，如：

```http
https://example.com/items/?limit=10&tool=plumbus
```

他們將收到一個**錯誤**回應，告訴他們查詢參數 `tool` 是不允許的：

```json
{
    "detail": [
        {
            "type": "extra_forbidden",
            "loc": ["query", "tool"],