send abstract method

Send request and resolve to a GatewayTransportResponse when the network call completes. Implementations should throw a TimeoutException or GatewayTransportError only for transport-level failures (DNS, TCP reset, TLS handshake, request timeout). HTTP errors (4xx / 5xx) are returned as a normal response with the appropriate statusCode.

Implementation

Future<GatewayTransportResponse> send(GatewayTransportRequest request);