how to reject a connection in server side ?
XDinEuro opened this issue · comments
Hi, I am using oatpp-websocket example from https://github.com/oatpp/example-websocket/blob/master/.
I have one use case, the server need to decline new connection when there exists two client.
I tried to change the code here from
void WSInstanceListener::onAfterCreate(const oatpp::websocket::WebSocket& socket, const std::shared_ptr<const ParameterMap>& params) {
SOCKETS ++;
OATPP_LOGD(TAG, "New Incoming Connection. Connection count=%d", SOCKETS.load());
/* In this particular case we create one WSListener per each connection */
/* Which may be redundant in many cases */
socket.setListener(std::make_shared<WSListener>());
}
to
void WSInstanceListener::onAfterCreate(const oatpp::websocket::WebSocket& socket, const std::shared_ptr<const ParameterMap>& params) {
SOCKETS++;
OATPP_LOGD(TAG, "New Incoming Connection. Connection count=%d", SOCKETS.load());
if (SOCKETS >= 3) {
SOCKETS = 2;
OATPP_LOGD(TAG, "More than two socket connected, will not listen to new ones");
socket.sendClose();
}
else {
socket.setListener(std::make_shared<WSListener>());
}
}
It works properly at first few attemps, but after few times the server stop responding to any connections even though I disconnect the previous two clients.
Another issue is, after I call socket.sendClose()
,
WSInstanceListener::onBeforeDestroy()
is not triggered. Thus I need to manually do SOCKETS = 2
.
Is there is better way to gracefully cut down the connections, or more straghtforward,
Is there a way to reject coming connections ?
+1
probably you need to accept the connection and close it from listener
Hello guys,
TLDR:
socket.getConnection().invalidate();
sendClose
just sends a close frame to peer. Then peer has to respond with close frame too.
And only after that both sides actually close the connection. - this is the "graceful way".
But the point is that it isn't always possible to follow graceful way due to multiple reasons:
- client may not follow the protocol
- connection issue (client changed carrier and connection just hanged)
- client application hanged
- any other reason
Your server has to account for all this (using pings/pongs) and drop bad clients.
How to drop connection:
socket.getConnection().invalidate();