have custom headers that you want a client in a browser to be able to see, you need to add them to your CORS configurations (read more in [CORS (Cross-Origin Resource Sharing)](../tutorial/cors.md){.internal-link target=_blank}), using the parameter `expose_headers` documented in <a href="https://www.starlette.io/middleware/#corsmiddleware" class="external-link" target="_blank">Starlette's CORS docs</a>....

import javax.servlet.http.HttpServletResponse;

import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;
import org.codelibs.core.lang.StringUtil;
import org.codelibs.fess.cors.CorsHandler;
import org.codelibs.fess.cors.CorsHandlerFactory;
import org.codelibs.fess.util.ComponentUtil;

public class CorsFilter implements Filter {

    private static final Logger logger = LogManager.getLogger(CorsFilter.class);

## 自定义头部

请注意，可以使用'X-'前缀添加自定义专有头部。

# 高级中间件

用户指南介绍了如何为应用添加[自定义中间件](../tutorial/middleware.md){.internal-link target=_blank} 。

以及如何[使用 `CORSMiddleware` 处理 CORS](../tutorial/cors.md){.internal-link target=_blank}。

本章学习如何使用其它中间件。

## 添加 ASGI 中间件

因为 **FastAPI** 基于 Starlette，且执行 <abbr title="Asynchronous Server Gateway Interface，异步服务器网关界面">ASGI</abbr> 规范，所以可以使用任意 ASGI 中间件。

中间件不必是专为 FastAPI 或 Starlette 定制的，只要遵循 ASGI 规范即可。

总之，ASGI 中间件是类，并把 ASGI 应用作为第一个参数。

# Advanced Middleware

In the main tutorial you read how to add [Custom Middleware](../tutorial/middleware.md){.internal-link target=_blank} to your application.

And then you also read how to handle [CORS with the `CORSMiddleware`](../tutorial/cors.md){.internal-link target=_blank}.

In this section we'll see how to use other middlewares.

## Adding ASGI middlewares

Lesen Sie mehr darüber in der [FastAPI-Dokumentation über Middleware](../advanced/middleware.md).

::: fastapi.middleware.cors.CORSMiddleware

Kann von `fastapi` importiert werden:

```python
from fastapi.middleware.cors import CORSMiddleware
```

::: fastapi.middleware.gzip.GZipMiddleware

Kann von `fastapi` importiert werden:

```python

	if corsList == "" {
		corsAllowOrigin = []string{"*"} // defaults to '*'
	} else {
		corsAllowOrigin = strings.Split(corsList, ",")
		for _, cors := range corsAllowOrigin {
			if cors == "" {
				return cfg, errors.New("invalid cors value")
			}
		}
	}
	cfg.CorsAllowOrigin = corsAllowOrigin

	if err = config.CheckValidKeys(config.APISubSys, kvs, DefaultKVS, deprecatedKeys...); err != nil {

!!! توجه "جزئیات فنی"
    شما همچنین می‌توانید از `from starlette.requests import Request` استفاده کنید.

- BucketACL (Use [bucket policies](https://min.io/docs/minio/linux/administration/identity-access-management/policy-based-access-control.html) instead)
- BucketCORS (CORS enabled by default on all buckets for all HTTP verbs, you can optionally restrict the CORS domains)
- BucketWebsite (Use [`caddy`](https://github.com/caddyserver/caddy) or [`nginx`](https://www.nginx.com/resources/wiki/))

die ein Client in einem Browser sehen können soll, müssen Sie diese zu Ihren CORS-Konfigurationen hinzufügen (weitere Informationen finden Sie unter [CORS (Cross-Origin Resource Sharing)](../tutorial/cors.md){.internal-link target=_blank}), unter Verwendung des Parameters `expose_headers`, dokumentiert in <a href="https://www.starlette.io/middleware/#corsmiddleware" class="external-link" target="_blank">Starlettes CORS-Dokumentation</a>....