# CORS（跨域资源共享）

<a href="https://developer.mozilla.org/en-US/docs/Web/HTTP/CORS" class="external-link" target="_blank">CORS 或者「跨域资源共享」</a> 指浏览器中运行的前端拥有与后端通信的 JavaScript 代码，而后端处于与前端不同的「源」的情况。

## 源

源是协议（`http`，`https`）、域（`myapp.com`，`localhost`，`localhost.tiangolo.com`）以及端口（`80`、`443`、`8080`）的组合。

因此，这些都是不同的源：

* `http://localhost`
* `https://localhost`
* `http://localhost:8080`

即使它们都在 `localhost` 中，但是它们使用不同的协议或者端口，所以它们都是不同的「源」。

## 步骤

import org.codelibs.curl.Curl;
import org.codelibs.curl.CurlResponse;
import org.codelibs.fess.app.web.base.login.ActionResponseCredential;
import org.codelibs.fess.app.web.base.login.EntraIdCredential;
import org.codelibs.fess.app.web.base.login.EntraIdCredential.EntraIdUser;
import org.codelibs.fess.app.web.base.login.FessLoginAssist.LoginCredentialResolver;
import org.codelibs.fess.crawler.Constants;

 * either express or implied. See the License for the specific language
 * governing permissions and limitations under the License.
 */
package org.codelibs.fess.helper;

import org.lastaflute.web.util.LaRequestUtil;

/**
 * Helper class for detecting and categorizing user agent types from HTTP requests.
 * This class analyzes the User-Agent header to determine which browser type is being used

    * `404`，用于**未找到**响应
    * 对于来自客户端的一般错误，可以只使用 `400`
* `500` 及以上的状态码用于表示服务器端错误。几乎永远不会直接使用这些状态码。应用代码或服务器出现问题时，会自动返回这些状态代码

/// tip | 提示

状态码及适用场景的详情，请参阅 <a href="https://developer.mozilla.org/en-US/docs/Web/HTTP/Status" class="external-link" target="_blank"><abbr title="Mozilla Developer Network">MDN 的 HTTP 状态码</abbr>文档</a>。

///

## 状态码名称快捷方式

再看下之前的例子：

{* ../../docs_src/response_status_code/tutorial001.py hl[6] *}

Wenn Sie mehr über Formularfelder und ihre Kodierungen lesen möchten, besuchen Sie die <a href="https://developer.mozilla.org/en-US/docs/Web/HTTP/Methods/POST" class="external-link" target="_blank"><abbr title="Mozilla Developer Network – Mozilla-Entwicklernetzwerk">MDN</abbr>-Webdokumentation für <code>POST</code></a>.

///

/// warning | Achtung

{* ../../docs_src/middleware/tutorial001.py hl[8:9,11,14] *}

/// tip | Порада

Не забувайте, що власні заголовки можна додавати, використовуючи <a href="https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers" class="external-link" target="_blank">префікс 'X-'</a>.

### Concurrency + Parallelism: Web + Machine Learning { #concurrency-parallelism-web-machine-learning }

With **FastAPI** you can take advantage of concurrency that is very common for web development (the same main attraction of NodeJS).

///

## Headers Personalizados { #custom-headers }

Ten en cuenta que los headers propietarios personalizados se pueden agregar <a href="https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers" class="external-link" target="_blank">usando el prefijo `X-`</a>.

 * into a ResultData object, and for retrieving the binary data from an AccessResultData object.
 * It extends the AbstractTransformer class.
 *
 * <p>
 * This transformer extracts the binary content from the response body of a web resource,
 * stores it as a byte array in the ResultData, and provides a method to retrieve this data
 * as a ByteArrayInputStream.
 * </p>
 *
 * <p>

    /**
     * The name of the request header.
     */
    public String name;

    /**
     * The value of the request header.
     */
    public String value;

    /**
     * The web configuration ID associated with this request header.
     */
    public String webConfigId;

    /**
     * The user who created this request header.
     */
    public String createdBy;

    /**