|Apache | Portals | WSRP4J|
The OASIS WSRP standard defines pluggable, user-facing, interactive web services with a common, well-defined interface and protocol for processing user interactions and providing presentation fragments suitably for aggregation by portals. WSRP standardizes web services at the presentation layer on top of the existing web services stack, builds on the existing web services standards and will leverage additional web services standards efforts, such as security efforts now underway, as they become available. The WSRP interfaces are defined in the Web Services Description Language (WSDL). In addition, WSRP defines metadata for self-description for publishing and finding WSRP services in registries. All WSRP services are required to implement a SOAP binding and optionally may support additional bindings.
In the definition of the WSRP standard and the JSR 168, the OASIS Technical Committee and the JSR 168 Expert group have closely collaborated to make sure that that both fit together well in portal architectures. JSR 168 compliant portlets can be exposed as WSRP compliant web services and conversely, WSRP services can be integrated through generic portlet proxies written to the Portlet API (see Figure below).
The WSRP4J project provides the WSRP4J Producer, which allows implementing such WSRP compliant services based on a free, open source software stack consisting of Tomcat, Axis and WSRP4J which in turn includes Pluto, the JSR 168 reference implementation. In addition, the WSRP4J project provides a generic proxy portlet written to the Portlet API, the WSRP4J Consumer (see Figure below).