Introduction

Web Services for Remote Portlets (WSRP) is a mechanism used to generate markup fragments on a remote system for display in a local portal application.This chapter describes how Oracle Service Bus provides Service Level Agreement (SLA) monitoring in applications that use WSRP.

WSRP Producers and Consumers

WSRP producer - (referred to as producer in this document) is a remote application, implements standards-based Web Services using the SOAP specification over HTTP. You can create a producer using WebLogic Portal or third-party implementations of WSRP.
WSRP consumer (referred to as a consumer in this document) is a portal application. Typically, the consumer application references WSDL of the producer when the portal is designed, and the consumer directly accesses the producer.

WSRP Architecture

This section describes the architecture of WSRP and shows how to enhance the architecture by adding Oracle Service Bus.

Figure 1-1 shows the WSRP SOAP request and response flow between a producer application and a consumer application.

Enhanced Architecture with Oracle Service Bus

Figure 1-2 shows how to use Oracle Service Bus as an intermediary between the producer and the consumer to provide Service Level Agreement (SLA) monitoring. You can use Oracle Service Bus in this.

Inbound Request: The consumer calls the proxy service in Oracle Service Bus.
Outbound Request: The proxy service routes the request, which is a message containing the SOAP body and transport headers, to the producer
Outbound Response: The producer sends a response to Oracle Service Bus.
Inbound Response: The proxy service sends a response to the consumer. The response is a message that contains the SOAP body and transport headers.

The remainder of this section describes how to configure Oracle Service Bus to send requests for WSRP services through proxy services. It describes services that a producer provides, along with other attributes of WSRP that must be used to configure Oracle Service Bus. This section also discusses how to monitor producers with increasing degrees of detail. Finally, it discusses load balancing and failover with WSRP.

WSRP Design Concepts

WSRP WSDLs

Table 1-1 describes various kinds of services offered by WSDLs. And WSDLs are referred to as ‘Producers’.

Table 1-1 Producer Services
Service	Description
Service Description	Required service. Describes the producer and the portlets that the producer makes available to consumers.
Markup	Required service. Manages user interaction with a remote portlet and returns the HTML markup used to render the portlet.
Registration	Optional service. Required for complex producers. Allows consumers to register themselves with the producer.
Management	Optional service. Provided by complex producers for managing portlet customization and portlet preferences.
Markup Extension	Provided by BEA Portal producers and replaces the Markup service. Markup Extension allows more efficient message handling by using multipart MIME messages for transmitting HTML markup content.

Each producer implements a minimum of two services, such as Service Description and Markup A simple producer offers just these two services. A complex producer, however, provides two additional services, such as Registration and Management. In addition, WebLogic Portal producers implement an extension service, such as Markup Extension that replaces the standard Markup service.

These services are described using a standard WSDL format. The producer supplies a single URL for retrieving its WSDL, which describes all the services that are provided by that producer. The end points for each service indicate whether the consumer should use transport-level security (HTTPs) or abstain from communication with the producer.

WSRP Messages

WSRP uses SOAP over HTTP for all messages exchanged between producers and consumers. In addition to using the standard message formats in the SOAP body, WSRP requires that consumers set at least a SOAPAction header, the cookie headers, and the usual HTTP headers, such as Content-Type. Producers return a session cookie, and any application-specific cookies, in the HTTP transport header of the response. The consumer must return the session cookie in subsequent request messages.

Interoperability Solutions for WSRP