Using Proxies with Authentication for HTTP Requests in Go

When working with HTTP requests, it's common to encounter situations where you need to use a proxy with authentication. This can be due to network restrictions or to improve performance. However, setting up proxies with authentication can be a bit tricky in Go.

The documentation for the net/http package (the standard library package for handling HTTP requests in Go) provides examples of how to use proxies, but they do not explicitly address the case of authenticated proxies. To handle this, you'll need to set up the HEADER in the transport to correctly authorize your proxy requests.

Here's how you can use proxies with authentication in your HTTP requests using the net/http package in Go:

1. Declare the authentication credentials: Start by declaring the username and password for the proxy authentication.

   auth := "username:password"

2. Encode the credentials: Encode the credentials using the base64 encoding.

   basicAuth := "Basic "   base64.StdEncoding.EncodeToString([]byte(auth))

3. Set the ProxyConnectHeader: Create a http.Header to hold the proxy authorization header and add the encoded credentials.

   transport.ProxyConnectHeader = http.Header{}
   transport.ProxyConnectHeader.Add("Proxy-Authorization", basicAuth)

4. Use the transport: Use the modified transport for your HTTP requests.

   client := &http.Client{
       Transport: transport,
   }

By following these steps, you can successfully use proxies with authentication in your HTTP requests in Go.