Another way of thinking about EPRs

• From: Martin Gudgin <mgudgin@microsoft.com>
• Date: Thu, 9 Dec 2004 15:46:51 -0800
• To: <public-ws-addressing@w3.org>
• Message-ID: <DD35CC66F54D8248B6E04232892B633804361866@RED-MSG-43.redmond.corp.microsoft.com>

I've noticed that whenever we talk about issues i001 and i008, that
there is an implicit assumption that we start with an EPR and go from
that to the message. I think that in many cases, the reverse is actually
true, that is, people start with SOAP messages with headers in and then
decide how to communicate to a potential sender what those messages
should look like ( WRT the headers ).

For example, I want to have people send me messages that look like the
three below. 

<soap:Envelope>
 <soap:Header>
   <wsa:To>http://example.org/weather</wsa:To>
   <m:ServiceLevel>Gold</m:ServiceLevel>
   <m:TxId>1234</m:TxId>
 </soap:Header>
 <soap:Body>
 . . .
 </soap:Body>
</soap:Envelope>

<soap:Envelope>
 <soap:Header>
   <wsa:To>http://example.org/weather</wsa:To>
   <m:ServiceLevel>Silver</m:ServiceLevel>
   <m:TxId>1234</m:TxId>
 </soap:Header>
 <soap:Body>
 . . .
 </soap:Body>
</soap:Envelope>

<soap:Envelope>
 <soap:Header>
   <wsa:To>http://example.org/weather</wsa:To>
   <m:ServiceLevel>Gold</m:ServiceLevel>
   <m:TxId>4567</m:TxId>
 </soap:Header>
 <soap:Body>
 . . .
 </soap:Body>
</soap:Envelope>

How can I communicate to my users that I want the messages to look like
this? Ah, I know, I'll send them an EPR. Here are the three EPRs for the
messages above ( my seperation between Props/Params is arbitrary ).

<wsa:EndpointReference>
 <wsa:Address>http://example.org/weather</wsa:Address>
 <wsa:ReferenceProperties>
  <m:ServiceLevel>Gold</m:ServiceLevel>
 </wsa:ReferenceProperties>
 <wsa:ReferenceParameters>
  <m:ServiceLevel>1234</m:ServiceLevel>
 </wsa:ReferenceParameters>
</wsa:EndpointReference>

<wsa:EndpointReference>
 <wsa:Address>http://example.org/weather</wsa:Address>
 <wsa:ReferenceProperties>
  <m:ServiceLevel>Silver</m:ServiceLevel>
 </wsa:ReferenceProperties>
 <wsa:ReferenceParameters>
  <m:ServiceLevel>1234</m:ServiceLevel>
 </wsa:ReferenceParameters>
</wsa:EndpointReference>

<wsa:EndpointReference>
 <wsa:Address>http://example.org/weather</wsa:Address>
 <wsa:ReferenceProperties>
  <m:ServiceLevel>Gold</m:ServiceLevel>
 </wsa:ReferenceProperties>
 <wsa:ReferenceParameters>
  <m:ServiceLevel>4567</m:ServiceLevel>
 </wsa:ReferenceParameters>
</wsa:EndpointReference>

Does this make any sense?

Gudge

Received on Thursday, 9 December 2004 23:46:56 UTC