Add some real messages to ASN.1 and handle pings on server

server/src/session_server.erl

@@ -23,13 +23,14 @@ handle_cast(_Msg, State) ->
 
 handle_info({ssl, Socket, Data}, State) ->
 	case 'StudySystemProtocol':decode('Request', Data) of
-		{ok, {foo, _}} ->
-			{ok, Encoded}
-				= 'StudySystemProtocol':encode('Response', {msg, "Foo"}),
+		{ok, {ping, _}} ->
+			{ok, Encoded} = 'StudySystemProtocol':encode(
+							  'Response', {ack, 'NULL'}),
 			ok = ssl:send(Socket, Encoded);
-		Result ->
-			io:format("Invalid message: ~p~n", [Result]),
-			ok
+		{error, {asn1, _Reason}} ->
+			{ok, Encoded} = 'StudySystemProtocol':encode(
+							  'Response', {error, invalidRequest}),
+			ok = ssl:send(Socket, Encoded)
 	end,
 	{noreply, State};
 handle_info({ssl_closed, _Socket}, State) ->