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Declarative XML Parsing - Adapter Data Readers/Writers

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Are you using adapter data reader / writer derived classes?

WCF LOB Adapter SDK team had introduced adapter XML data readers/writers in Beta 2.  Since an adapter developer, who is using WCF LOB Adapter SDK to build an adapter, is working with XML messages in inbound / outbound handlers, the parsing/constructing XML messages for various operations can consume a lot of time.  

Adapter Developer needs to transform WCF request message (XML) to the corresponding LOB request and similarly a response from the LOB needs to be transformed to the corresponding WCF response message (XML). The Adapter Data Writer / Reader is an opt-in metadata-driven component in Adapter SDK that can be used by the Adapter Developer to perform this transformation using an event model. The Adapter Data Writer provides an ability to parse incoming WCF (XML) requests via an event model where for a given state of the XML parser a corresponding metadata event will be raised. The Adapter Data Reader provides a way to walk through the tree of metadata for a given response and raise events at each significant point to the Adapter Developer for the LOB data to be made part of the generating WCF response. The Adapter Developer has the flexibility to use this feature or provide own implementation for request parsing and response generation.

 

We had a sample adapter that used XmlDictionaryReader/XmlDictionaryWriter to do all the required message parsing and construction. In one of our experiments, we converted it to use adapter data readers/writers. The results were very impressive! The reader size code shrunk by 50% and the writer code yielded savings of about 70%. The simple SQL adapter sample shows how these adapter data reader / writers are used.

Unfortunately, the team has changed their plan to deliver this feature in RTW (V1) timeframe. This is because we were not able to get sufficient customer validation and coverage on this feature for the RTW timeframe.

If you are using WCF LOB Adapter SDK RC, and have or planning to use these adapter data readers / writers for your solution, I would like to hear from you . If we can get enough feedback from you, there is a high possiblity of putting this feature in the next service pack post-RTW.

Thanks!