config {   virtual_hosts {     name: " "     domains: "*"     routes {       match {         path: ""       }       route {         cluster_header: " "       }     }   }   request_headers_to_add {     header {       key: " "       value: "%UPSTREAM_HEADER_BYTES_SENT%"     }   } } headers {   headers {     key: "x-forwarded-proto"     value: " "   }   headers {     key: ":path"   } } 