But remember that when you import `Query`, `Path`, `Header`, and others from `fastapi`, those are actually functions that return special classes.

///

/// info

To declare headers, you need to use `Header`, because otherwise the parameters would be interpreted as query parameters.

///

## Automatic conversion { #automatic-conversion }

 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */
package jcifs.internal.smb2.ioctl;

import jcifs.Encodable;
import jcifs.internal.util.SMBUtil;

/**
 * SMB2 Validate Negotiate Info request data structure. This structure is used to validate
 * that the negotiated SMB2 dialect matches what was originally negotiated.
 *
 * @author mbechler
 *
 */

接著在建立 `FastAPI` 應用時使用它。

然後你可以將環境變數 `OPENAPI_URL` 設為空字串，以停用 OpenAPI（包含文件 UI），如下：

<div class="termy">

```console
$ OPENAPI_URL= uvicorn main:app

<span style="color: green;">INFO</span>:     Uvicorn running on http://127.0.0.1:8000 (Press CTRL+C to quit)
```

</div>

之後若你造訪 `/openapi.json`、`/docs` 或 `/redoc`，會看到如下的 `404 Not Found` 錯誤：

```JSON
{
    "detail": "Not Found"
}

	s.IsValid(w, r)
}

// DiskInfoHandler - returns disk info.
func (s *storageRESTServer) DiskInfoHandler(opts *DiskInfoOptions) (*DiskInfo, *grid.RemoteErr) {
	if !s.checkID(opts.DiskID) {
		return nil, grid.NewRemoteErr(errDiskNotFound)
	}
	info, err := s.getStorage().DiskInfo(context.Background(), *opts)
	if err != nil {
		info.Error = err.Error()
	}
	return &info, nil
}

### 查看自动 API 文档 { #check-the-automatic-api-docs }

现在，运行 `fastapi` 命令：

<div class="termy">

```console
$ fastapi dev

<span style="color: green;">INFO</span>:     Uvicorn running on http://127.0.0.1:8000 (Press CTRL+C to quit)
```

</div>

然后在 [http://127.0.0.1:8000/docs](http://127.0.0.1:8000/docs) 打开文档。

下图显示的是主应用 API 文档，只包括其自有的*路径操作*。

/// note | 技术细节

`Header` 是 `Path`、`Query`、`Cookie` 的**兄弟类**，都继承自共用的 `Param` 类。

注意，从 `fastapi` 导入的 `Query`、`Path`、`Header` 等对象，实际上是返回特殊类的函数。

///

/// info | 信息

必须使用 `Header` 声明 header 参数，否则该参数会被解释为查询参数。

///

## 自动转换 { #automatic-conversion }

`Header` 比 `Path`、`Query` 和 `Cookie` 提供了更多功能。

大部分标准请求头用**连字符**分隔，即**减号**（`-`）。

import java.util.List;
import java.util.Map;

import org.codelibs.fess.opensearch.user.exentity.User;
import org.dbflute.Entity;
import org.dbflute.dbmeta.AbstractDBMeta;
import org.dbflute.dbmeta.info.ColumnInfo;
import org.dbflute.dbmeta.info.UniqueInfo;
import org.dbflute.dbmeta.name.TableSqlName;
import org.dbflute.dbmeta.property.PropertyGateway;
import org.dbflute.dbway.DBDef;
import org.dbflute.util.DfTypeUtil;

/**

    client = get_client()
    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": {
                "/items/": {
                    "post": {
                        "summary": "Read Items",

# 表单模型 { #form-models }

你可以在 FastAPI 中使用 **Pydantic 模型**声明**表单字段**。

/// info | 信息

要使用表单，首先安装 [`python-multipart`](https://github.com/Kludex/python-multipart)。

确保你创建一个[虚拟环境](../virtual-environments.md)，激活它，然后再安装，例如：

```console
$ pip install python-multipart
```

///

/// note | 注意

自 FastAPI 版本 `0.113.0` 起支持此功能。🤓

///

## 表单的 Pydantic 模型 { #pydantic-models-for-forms }

needed by API systems is data "<dfn title="also called marshalling, conversion">serialization</dfn>" which is taking data from the code (Python) and converting it into something that can be sent through the network. For example, converting an object containing data from a database into a JSON object. Converting `datetime` objects into strings, etc.

Another big feature needed by APIs is data validation, making sure that the data is valid, given certain parameters. For example, that some...