Re: Fw: invoke/receive/reply

[Michael B Mccarthy <mbmccarthy@us.ibm.com>]

 I believe you're asking about WMQ with the Request-Reply question.  The
short answer is that they DO form a pair.  The slightly less short answer
is this.  WMQ has a 364 byte control area before the data message.  Two of
its fields are a 24-byte "Message ID" and a 24-byte "Correllation ID".
When a message is sent the system generates a unique Message-ID.  The
sender should also code a "Message Type" in the MSGTYPE (vs. a "Datagram",
etc.)  The standard convention is for the receiver of the message to move
the Message-ID field to the Correllation ID as before sending the reply
back.  The original sender then does an MQGET with the Correllation ID
coded and will only pick up the reply to the original request.  I don't
know exactly how the pieces work in the other environments but this is
probably the WMQ counterpart.

Sincerely,


Michael B. McCarthy
IBM Software Group
Business Integration Specialist SSR
Office (781)334-3578
mbmccarthy@us.ibm.com


                                                                           
             "Antony Miguel"                                               
             <antony.miguel@sc                                             
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             07/07/2004 12:16          g>                                  
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                                       Fw: invoke/receive/reply            
                                                                           
                                                                           
                                                                           
                                                                           
                                                                           
                                                                           




Is receive-reply equivalent to the WSDL "Notification" type of operation?
If so, then does it mean the same thing to execute an invoke with no
inputVariable and an outputVariable?

e.g. is

            <receive partnerLink="plink" portType="ptype" operation="op"
variable="myvar" />

equivalent to

            <invoke partnerLink="plink" portType="ptype" operation="op"
outputVariable="myvar" />

thanks

Antony

----- Original Message -----
From: Antony Miguel
To: wsbpel-comment@lists.oasis-open.org
Sent: Tuesday, July 06, 2004 2:14 PM
Subject: Re: invoke/receive/reply

I should add to this question that an alternative I might expect would be a
<pick> - <reply> pair.

Antony Miguel
Scapa Technologies
antony.miguel@scapatech.com
+44 131 550 1766
 ----- Original Message -----
 From: Antony.Miguel@scapatech.com
 To: wsbpel-comment@lists.oasis-open.org
 Sent: Tuesday, July 06, 2004 12:32 PM
 Subject: invoke/receive/reply

 Hi,

 Hopefully this is the right place to be asking this question.  If the
 question is not appropriate or anyone knows of a better place to ask then
 please let me know.

 I recently saw an example BPEL program where there were two activities in
 a <flow>, one doing a <receive>, and the other sending a message to it
 using a <reply>.  I can't find the example again and I may have just
 misinterpreted it but am I correct in thinking that in BPEL, a <receive>
 always receives from an invoke (or from some externally bound incoming
 message), and never from a <reply>?

 My understanding is an invoke should always mean a receive-reply pair
 somewhere.  Is this correct?

 thanks

 Antony Miguel
 Scapa Technologies
 antony.miguel@scapatech.com
 +44 131 550 1766