http:http_connection_over_proxy(+Proxy, +URLParts, +Endpoint, -StreamPair, +Options, -NewOptions)[multifile, library(http/http_hook)]
Try to connect to the host Endpoint via Proxy for the purposes of retrieving the resource identified by URLParts. Different options can be returned in NewOptions, which may be required if you have defined a non-standard proxy method in proxy_for_url/3 (such as one requiring authentication)
 http:http_connection_over_proxy(+Proxy, +Parts, +HostPort, -StreamPair, +OptionsIn, -OptionsOut)[multifile, library(http/http_ssl_plugin)]
Facilitate an HTTPS connection via a proxy using HTTP CONNECT. Note that most proxies will only support this for connecting on port 443