[ebxmlms-general] Challenge with wildcarded Application Contexts and acknowledgements

[Gait B. <gai...@ti...>]

Hi team,

we've discovered a challenge with the sending back of acknowledgements =
(and probably statuses as well) when using wildcards in our Application =
Contexts.

Basically, we want to use a single AC for all incoming data, and have =
all four fields in there marked as a wildcard. Since we need to specify =
a toMshUrl, we stuck that to http://localhost:8080/msh/. We don't intend =
to send any message out using the attached Request object, so in =
principle, it's a dummy value. However, we discovered that the MSH uses =
the same URL to reply to acknowledgement requests (and from the code, =
status requests). The net result is that we send an acknowledgement, but =
not to the MSH of the sender, and the ack gets lost. As long as there is =
one other MSH that we're communicating with, we can set the toMshUrl or =
our receive Request to it's URL, but that will fail as soon we start =
communicating wiht multiple parties.

I see two solutions to the challenge,
1) instead of using the Connection that is hooked with the AC receiving =
the message, extract the From Party URI that is in the message and build =
a Connection to that URI on the fly.
2) Add another table to the MSH where we can maintain reply connections =
with specific application contexts, without using them for the routing =
of incoming messages. The table could also be used to store alternate =
URI's when the main one is off line, or even URI's to report error =
messages.=20
When no entry is available, the default URI for acknowledgements should =
be taken from the message as in 1).

Come to think of it, such a design is a lot more inline with CPPA as =
well. The trick is to separate the configuration of allowed channels =
from the routing to registered listeners.

Yes, I am aware this is not an easy task, but I believe it is worth the =
effort.

-- Gait.

PS I'd love to help develop, but I'm seriously resource challenged at =
the moment.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Gait Boxman
Manager Advanced Technology & Standards
TIE Product Development BV
Amsterdam, The Netherlands
Tel: +31 20 658 9091  Fax: +31 20 658 9945
E-mail: gai...@ti...  WWW: www.TIEglobal.com
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~