Discussion on Issues Rel 108 and 115

[Tom Rutt <tom@coastin.com>]

These issues deal with the semantics of poll response for messages which 
were not delivered due to a fault

Current semantics of returning fault are as follows:

For resposne reply pattern a single message fault is returned in the 
response to the reliable request.

For callback reply pattern, a single message fault is returned in the 
callback containing the Fault element.

It is not clearly stated, but the receving RMP could batch a bunch of 
acks in a single callback message, but there is not way to do this
for faults.

Currently there is not way to indicate in a response to a poll that a 
message was not delivered due to  a fault.  The response to the
poll merely lists all message IDs in the poll range which were 
delivered.  Messages not in that list may be held, or may have been not
delivered due to a fault condition.

A fault element in a response to a poll, only indicates a problem wiht 
the poll request itself.  It cannot be used to indicate a fault on a prior
reliable messasge request.

The current Response syntax is as follows:

<!--

 Response Header Type and it's elements 

  -->
- <#> <xsd:complexType name="*ResponseType*">
- <#> <xsd:complexContent>
- <#> <xsd:extension base="*wsrm:RmBaseType*">
- <#>       <xsd:sequence>
              <xsd:element name="*RefToGroupId*" 
type="*wsrm:ResponseElementType*" maxOccurs="*unbounded*" />
     </xsd:sequence>
  </xsd:extension>
 </xsd:complexContent>
</xsd:complexType>


We could add a new element to the responst type as follows

<xsd:complexType name="*ResponseType*">
- <#> <xsd:complexContent>
- <#> <xsd:extension base="*wsrm:RmBaseType*">
- <#>       <xsd:sequence>
              <xsd:element name="*RefToGroupId*" 
type="*wsrm:ResponseElementType*" maxOccurs="*unbounded*" />
           <xsd:element name="*RefToFaults*" type="*wsrm:FaultsRefType*" 
maxOccurs="*unbounded*" />

     </xsd:sequence>
  </xsd:extension>
 </xsd:complexContent>
</xsd:complexType>

<xsd:complexType name="*FaultsRefType*">
- <#> <xsd:complexContent>
- <#>       <xsd:sequence>       
               <xsd:element name="*FaultCode*" type="xsd:string" 
maxOccurs="*1*" />
              <xsd:element name="*RefToGroupId*" 
type="*wsrm:ResponseElementType*" maxOccurs="*unbounded*" />
    </xsd:sequence>
</xsd:complexContent>
</xsd:complexType>            

An example of the structure of the RefToFaults element (repeated here 
twice) would be as follows


   <RefToFaults>

         <FaultCode>  processingError </FaultCode>

          <RefToGroupID> ... list of message ids in group a which had processing error fault ... </RefToGroupID>
           <RefToGroupID> ... list of message ids , in group b which had processing error fault ... </RefToGroupID>
    </RefToFaults>

   <RefToFaults>

         <FaultCode>  BadHeader </FaultCode>

          <RefToGroupID ... list of message ids  in group a which had Bad header fault ... </RefToGroupID>

    </RefToFaults>

The major problem with this is the requirmenet for the receiver to remember which fault codes arose for each non-delivered message.

However, it would give full functionality to the poll response.

Tom Rutt







-- 

----------------------------------------------------
Tom Rutt		email: tom@coastin.com; trutt@fsw.fujitsu.com
Tel: +1 732 801 5744          Fax: +1 732 774 5133