[Quickfix-developers] Recovering from client side sequence number amnesia

[Dale W. <wil...@oc...>]

Due to some network problems, I may (or may not) have managed to send this message yesterday.   Please forgive it if it's a duplicate.

Dale

Hi QuickFIX developers,

I think I've run into a "you-can't-get-there-from-here" problem, but I'd like to be sure I'm not missing something.

The situation I'm trying to handle happens when the client (initiator) is recovering from a significant failure and has lost track of the sequence number expected by the server (acceptor).  The client sends logon message a sequence number that is less than the one expected by the server.  The server responds, correctly, with a logout message.  If the server is based on QuickFIX this logout message will contain a Text field giving the expected sequence number. 

   i.e.: 58=MsgSeqNum too low, expecting 7 but received 1

What I would like to do is detect this Logout message; inform the user of the situation; and allow them to verity that the sequence number should be reset.

Unfortunately as far as I have been able to determine, the Logout message containig the expected sequence number never reaches the application code.  QuickFIX determines that this is not a valid sequence of messages:

  [Session::verify calls Session::validLogonState and throws an exception when it returns false. ] 

and calls Application::onLogout()  (twice, actually, but who's counting.) The body of the message containing the expected sequence number isn't available vis the onLogout call -- so I can't find a way to determine what sequence number is expected.

My work around for this will be to read the log, identify the logout message, and parse it to find the expected sequence number -- unless, of course, someone tells me that there's a better way.

Any suggestions would be appreciated,

Dale


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Dale Wilson, Senior Software Engineer
Object Computing, Inc. (OCI)
http://www.ociweb.com/ http://www.theaceorb.com/
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