How to apply subprotocol parameter

[abitcyanine]

Our old server applies the subprotocol parameter on websocket. Now we need to use oatpp in the server. How to apply the subprotocol parameter?

[Leonid Stryzhevskyi]

Hello @abitcyanine ,

oatpp doesn't check for subprotocol and at the moment just ignores it.
So you have to manually add a subprotocol check in the handshake.
Should be something like that:

ENDPOINT("GET", "ws", ws, 
         HEADER(String, subprotocol, "Sec-WebSocket-Protocol"), //< protocol header
         REQUEST(std::shared_ptr<IncomingRequest>, request)) 
{
  /* check subprotocol value */
  OATPP_ASSERT_HTTP(subprotocol == "my-subprotocol", Status::CODE_400, "unknown subprotocol")
  
  /* do the handshake */
  auto response = oatpp::websocket::Handshaker::serversideHandshake(request->getHeaders(), websocketConnectionHandler);

  /* agree on subprotocol */
  response->putHeader("Sec-WebSocket-Protocol", "my-subprotocol");
  
  return response;
};

Regards,
Leonid

[abitcyanine]

OK, I'll try the method you provided. Thank you for your reply