Dear WG Members,
I've had an opportunity to evaluate the Apache Axis project
(http://xml.apache.org/axis/index.html) recently. Axis is a Web services
toolkit built on SOAP, and appears to be a good fit for our phase 2
application interface. There are numerous advantages to building on this
type of toolkit:
- It is flexible, providing support for SOAP 1.1, parts of 1.2 (will
eventually support all of 1.2) and SOAP with attachments
- It greatly simplifies implementing Web services
- It would enable us to expose much of the already written phase 1 code as
Web services
- It understands WSDL and simplifies exposing it for all implemented
services (simply append "?wsdl" to the end of the service name). WSDL, for
those not familiar with it, is an XML language for describing Web services.
It is important because it can be used to generate client stubs, and is what
makes the implemented service protocol neutral (by removing the need for
clients to understand SOAP).
Some issues that need considered:
- The long-standing issue of how to send RDF using SOAP in a way that is
meaningful to the client. This problem is well documented in
http://www-106.ibm.com/developerworks/webservices/library/ws-soaprdf/. The
options boil down to sending the data as XML, or sending it as raw RDF (in
the form of a big text literal). Sending it as XML seems the more useful
approach since it would be useful in that form to XML applications. RDF
applications could still create statements from it, with some effort on
their part.
- How to document the services. Businesses do this using well-known UDDI
registries. Do we do the same? Do we create our own?
Your comments and suggestions are welcome. I would especially like to hear
from anyone who has experience with Axis.
Best Regards,
Harry Wagner
OCLC / DCMI
Dublin, OH 43017
(614) 761-5178
mailto:[log in to unmask]
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