Request change to ActiveMessaging::AbortMessageException

[GoogleCodeExporter]

Raising ActiveMessaging::AbortMessageException is a great way to indicate
that a message needs to be re-queued, however there are some conditions in
which after the message is re-queued, we want to exit the entire poller
process (for example, if a message processing method detecs that the
database server has a problem and can't reconnect).  If the poller were
stopped and restarted (in some of these instances), the error condition is
remedied.  

I'd like to suggest that ActiveMessaging::AbortMessageException be extended
to optionally take an options hash on the constructor, so that parameters
can be passed with the exception. I would also propose that the first
parameter to be handled is the must_exit parameter, which indicates to the
higher-level processor to exit the processor after the message has been
requeued. 

in activemessaging.rb, the exception class becomes:
class AbortMessageException < Exception #:nodoc:
    attr_reader :exit_process
    def initialize(options={})
      @exit_process = options[:exit_process]
    end
  end

In gateway.rb, the handling clause for the exception becomes:
              rescue ActiveMessaging::AbortMessageException =>exception_detail
                abort_message subscription, message
                abort = true
                Process.exit if exception_detail.exit_process
                return
              ensure
                acknowledge_message subscription, message unless abort
              end
And the processor code that detects the situation that requires a complete
restart signals that by: 
raise ActiveMessaging::AbortMessageException.new({:exit_process=>true})

(monit or some other type of method could be used to see that poller has
exited, and have it restart)

Original issue reported on code.google.com by brian.mo...@gmail.com on 8 Sep 2008 at 4:42

[GoogleCodeExporter]

Oops, please change must_exit to exit_process in the above message.

Original comment by brian.mo...@gmail.com on 8 Sep 2008 at 4:43

[GoogleCodeExporter]

It looks like an unsubscribe will have to occur before the Process.exit, 
otherwise
the recently requeued message will be lost on exit, since it's been read 
already.

Original comment by brian.mo...@gmail.com on 8 Sep 2008 at 5:38