request method
A function called when a request reaches this Link
Implementation
@override
Stream<Response> request(Request request, [NextLink? forward]) {
final link = _link;
if (link is HttpLink)
return _handleHttpRequest(link, request, forward);
else if (link is WebSocketLink)
return _handleWebSocketRequest(link, request, forward);
else
return link.request(request, forward);
}