ClientImpl and SSLClient let callers set origin credentials with
set_basic_auth()/set_bearer_token_auth(), but WebSocketClient could only
take a fixed Authorization header through its constructor. Add both
setters: each connect() adds the Authorization header to the upgrade
request from the current credentials (Basic over Bearer), unless the
constructor headers already carry one, and never to the proxy's CONNECT
request.
Through a CONNECT proxy it is the proxy that connects to the origin, and the CONNECT target was always the original hostname, so there was no way to send the tunnel to another address. set_tunnel_hostname_addr_map() sets that target on SSLClient, Client and WebSocketClient. The CONNECT request's Host follows it, including the Digest retry, while the Host header, the SNI and the certificate check inside the tunnel keep the original hostname. The map is also copied to a redirect client.
set_hostname_addr_map() is deprecated in favor of set_direct_hostname_addr_map(), which behaves the same and names the connection it applies to. The two maps are independent and correspond to curl's --resolve and --connect-to; neither applies to the proxy's own address.
WebSocketClient gets the proxy setters Client has: set_proxy(),
set_proxy_basic_auth(), set_proxy_bearer_token_auth(), set_no_proxy()
and, in SSL builds, set_proxy_digest_auth(). connect() opens a CONNECT
tunnel for ws:// as well as wss:// (RFC 6455 4.1) and sends the proxy
credentials on the CONNECT request only. A proxy that does not answer
200 is reported as Error::ProxyConnection, with its status and headers
in Result.
addr_map_ only accepted IP literals as mapped values; a non-IP value was
passed as the `ip` argument and rejected by getaddrinfo's AI_NUMERICHOST
path. The lookup in ClientImpl::create_client_socket and
WebSocketClient::connect now checks the mapped value with
detail::is_ip_address: IP literals keep the existing AI_NUMERICHOST path,
while hostnames are passed as the connect host so they get resolved.
host_ is never touched, so it keeps supplying the Host header and SNI in
both cases.
is_ip_address() moved into the non-SSL detail block so that both client
code paths can use it without CPPHTTPLIB_SSL_ENABLED.
This also fixes the documented Unix domain socket client example, where
the mapped value is a socket path: it previously took the AI_NUMERICHOST
path and never reached the AF_UNIX branch in create_socket.
Replace the hand-built upgrade request string in
perform_websocket_handshake with the same Request,
write_request_line, and check_and_write_headers path used by
ClientImpl::open_stream. Add WebSocketClient::prepare_default_headers
to inject Host and User-Agent defaults; protocol-mandatory headers
(Upgrade, Connection, Sec-WebSocket-Key/Version) are always
overwritten.
Kim, Hyuk