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);

    validations:
      required: false
  - type: textarea
    id: logs
    attributes:
      label: "Logs"
      description: "If possible please include gopls logs. Instructions for capturing them can be found here: https://github.com/golang/tools/blob/master/gopls/doc/troubleshooting.md#capture-logs"
    validations:

## 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。

### 4. (optional) RNN conversion support
If converting TF RNN to TFLite fused RNN ops, please prefix [RNN] in the title.

### 5. (optional) Any other info / logs

Also, please include a link to a GraphDef or the model if possible.

**Any other info / logs**

Include any logs or source code that would be helpful to diagnose the problem.
If including tracebacks, please include the full traceback. Large logs and files

!!! note "Technische Details"

!!! note "Technical Details"

1. Return prevResult

## Troubleshooting

### Collecting Logs

#### Using `istioctl`/helm

- Set: `values.global.logging.level="cni:debug,ambient:debug"`
- Inspect the pod logs of a `istio-cni` Daemonset pod on a specific node.

#### From a specific node syslog

The CNI plugins are executed by threads in the `kubelet` process.  The CNI plugins logs end up the syslog

    但是如果你想让浏览器中的客户端看到你的自定义请求头, 你需要把它们加到 CORS 配置 ([CORS (Cross-Origin Resource Sharing)](cors.md){.internal-link target=_blank}) 的 `expose_headers` 参数中,在 <a href="https://www.starlette.io/middleware/#corsmiddleware" class="external-link" target="_blank">Starlette's CORS docs</a>文档中.

!!! note "技术细节"
    你也可以使用 `from starlette.requests import Request`.