Re: [wsbpel] Assigning the Value of the Service-Ref Element

[Alex Yiu <alex.yiu@oracle.com>]

Hi, Andrew,

Basically your interpretation is in sync with my expectation.

Using the same example, the BPEL compiler will look at the value in the from-spec.
It looks at both reference-schema URI attribute value and the QName of the child element
(e.g. "wsaaddr:EndpointReference").

The compiler will decide whether it "understands" / "recognizes" the combination of these 2 values.
If so, the compiler will try to verify details of the child element
If compiler does not recognize the URI and QNAME, it should generate an error.

Thanks.


Regards,
Alex Yiu



andrew.francis@elf.mcgill.ca wrote:

Quoting Alex Yiu <alex.yiu@oracle.com>:

  

I saw two emails asking about how to make use of service-ref element in
BPEL.
    

I cross-posted to implementation.

  

          o from one XML element variable to a parterLink:
                + If the schema of the XML element variable references
                  to bpws:service-ref directly, then it seems to me that
                  we can do runtime checking. Compile-time checking is
                  not that feasible in that case.
    

[lines deleted]

  

I hope I have answered your questions. :-)  (And, not confusing u ...)
    

Thanks for answering. If I understand the gist of your response,
<service-ref> does not lend itself to compile time checking. I still
have questions. Using the example from 16.3.2:

<assign>
   <copy>
      <from>
          <!-- adding missing reference-schema attribute -->
          <service-ref reference-schema="wsaddr">
              <wsaaddr:EndpointReference>
               <wsaaddr:Address>xs:anyURI</wsaaddr:Address>

<wsaaddr:ServiceName>ars:RegistrationService</wsaaddr:ServiceName>
              </wsaaddr:EndpointReference>
          </service-ref>
       </from>
          <to partnerLink="auctionRegistrationService"/>
    </copy>
</assign>

A BPEL "compiler" encounters this fragment. How is the
<service-ref reference-schema="wsaaddr"> element interpreted
at compile time?

Does the compiler decide whether it (or its underlying BPEL runtime
component) "understands" the "wsaaddr" schema? Assuming the compiler
"understands" the schema, it does syntax/semantic checking. If the
compiler does not understand "wsaaddr," it generates a "Does not
understand schema" and gives up. Is this an acceptable interpretation?


Cheers,
Andrew