Duplicate CORS response headers

[frudder]

1. I use gin-contrib/cors pkg to handle cross-origin requests
2. I used ReverseProxy to proxy downstream services in the project. The CORS response headers from the downstream service are duplicated with the headers from gin-contrib/cors, such as Access-Control-Allow-Origin. My downstream service is a Java project.

[hubeoo]

this is a ReverseProxy issue

[frudder]

this is a ReverseProxy issue

I'm sorry, I didn't make myself clear. I am using the implementation of ReverseProxy in the reverseproxy.go file of the Go standard library net/http/httputil