Data Sources as Web Services

WSO2 ('WS OH 2') is growing in popularity and the team continues to
produce quality products. The WSO2 (a.k.a. Web Services Oxygen Tank)
team that has pulled together a platform around Apache SOA projects,
producing an application server, ESB, Web 2.0 mashup engine, and more.
Most recently, they have released Version 2.1 of the Web Services
Application Server (WSAS). The release includes a lot of compelling
features, but this article focuses upon WSO2 Data Services -- a new
feature available in WSO2's WSAS 2.0 platform. The author introduces
Data Services, examining their architecture and utilization, and
exploring pros and cons of this convenient feature. Data services are
standard web services that have been configured within WSAS to map
to data source calls to one or more backend data sources. Configuration
is captured in XML and can either be performed by hand and uploaded as
a complete deployment module, or deployed via the web-based Data
Service configuration wizard. Once deployed, these services can either
be consumed by other WSAS services or be made available to external
clients. Data Services are essentially the SOA-equivalent of the Data
Access Object pattern. Granted, Data Services are at a much higher
level of abstraction, but they serve a similar role in a layered
architecture. They enable higher level services or even client
applications to access underlying datasets without regard for the
implementation details involved... The heart of any enterprise
application is data. Applications provide the ability to view, sort,
filter, edit, create, and delete data. In a SOA, access to data is
also paramount. Typically this involves wrapping an existing business
object (EJB or POJO) with a web service. Another option is to bypass
this additional layer and directly expose data capabilities via WSO2
Data Services. Data services are convenient, configurable, and great
for service oriented data for a demo or even as a part of a SOA. More Information