Flask is a tool for storing the contents of the TcpStream and creating an http Request/Response
use flask::httpx::read_http_request;
fn proxy_tcp_stream(stream: TcpStream, proxy_addr: SocketAddr) {
let _proxy_add_str = format!("{}", proxy_addr);
let proxy_addr_hdr = HeaderValue::from_str(&_proxy_add_str).unwrap();
let mut req = read_http_request(stream.try_clone().unwrap()).unwrap();
// In a real system you should implement remove_hop_by_hop_headers. It's commented out here for simplicity.
// *req.headers_mut() = remove_hop_by_hop_headers(req.headers());
let req_headers = req.headers_mut();
req_headers.remove(http::header::HOST);
req_headers.insert(http::header::HOST, proxy_addr_hdr);
handle_request(stream, req);
}