Building an asynchronous web service with OSB:Java Network

A few weeks ago I made a blogpost over how you can build an asynchronous web service with JAX-WS. In this blogpost I will do the same in the Oracle Service Bus. What you probably already know is that OSB Proxy Service does not support asynchronous calls. This does not mean that it is impossible to do asynchronous calls in the OSB. To make this work I have the following setup.

A HTTP Proxy Service -> JMS Business Service -> Queue -> JMS Proxy Service -> HTTP Business Service.

I start with the WSDL which has two operations execute and callback.

<?xml version="1.0" encoding="UTF-8"?>
<wsdl:definitions xmlns:wsdl="http://schemas.xmlsoap.org/wsdl/" xmlns:inp1="http://xmlns.oracle.com/singleString" xmlns:tns="http://xmlns.oracle.com/AsyncEmployeeService" xmlns:emp="http://employee" xmlns:soap="http://schemas.xmlsoap.org/wsdl/soap/" name="AsyncEmployeeService" targetNamespace="http://xmlns.oracle.com/AsyncEmployeeService">
<wsdl:types>
<xsd:schema xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns="http://employee" xmlns:xs="http://www.w3.org/2001/XMLSchema" targetNamespace="http://employee" elementFormDefault="qualified" attributeFormDefault="qualified">
<xs:element name="Employee" type="Emp"/>
<xs:element name="EmployeeResponse" type="xs:string"/>
<xs:complexType name="Emp">
<xs:sequence>
<xs:element name="empno" type="xs:int"/>
<xs:element name="ename" type="xs:string"/>
<xs:element name="job" type="xs:string" minOccurs="0"/>
</xs:sequence>
</xs:complexType>
</xsd:schema>
</wsdl:types>
<wsdl:message name="callbackMessage">
<wsdl:part name="callback" element="emp:EmployeeResponse"/>
</wsdl:message>
<wsdl:message name="requestMessage">
<wsdl:part name="request" element="emp:Employee"/>
</wsdl:message>
<wsdl:portType name="callback_ptt">
<wsdl:operation name="callback">
<wsdl:input message="tns:callbackMessage"/>
</wsdl:operation>
</wsdl:portType>
<wsdl:portType name="execute_ptt">
<wsdl:operation name="execute">
<wsdl:input message="tns:requestMessage"/>
</wsdl:operation>
</wsdl:portType>
<wsdl:binding name="execute_pttBinding" type="tns:execute_ptt">
<soap:binding transport="http://schemas.xmlsoap.org/soap/http"/>
<wsdl:operation name="execute">
<soap:operation soapAction="execute" style="document"/>
<wsdl:input>
<soap:body use="literal" namespace="http://xmlns.oracle.com/AsyncEmployeeService"/>
</wsdl:input>
</wsdl:operation>
</wsdl:binding>
<wsdl:binding name="callback_pttBinding" type="tns:callback_ptt">
<soap:binding transport="http://schemas.xmlsoap.org/soap/http"/>
<wsdl:operation name="callback">
<soap:operation soapAction="callback" style="document"/>
<wsdl:input>
<soap:body use="literal" namespace="http://xmlns.oracle.com/AsyncEmployeeService"/>
</wsdl:input>
</wsdl:operation>
</wsdl:binding>
</wsdl:definitions>

The execute operation is used in the HTTP Proxy Service and the callback operation in the HTTP Business Service. The HTTP Proxy Service does the following:

retrieves the Addressing MessageID from the header, $header/wsa05:MessageID/text() , In this case you need to use the 2005 / 08 addressing.
retrieves the Addressing Reply URL from the header, $header/wsa05:ReplyTo/wsa05:Address/text(). This URL will be used in the callback HTTP Business Service
Make a new Body for the Queue which contains the WS Request and the Reply URL
Set the JMS CorrelationID with MessageID as value, use the Transport Header activity
Call the JMS Business Service.

The JMS Business Service put the Message on a Queue.

The JMS Queue has the following exception properties, these settings are very important else you can create a loop when something goes wrong, with these settings the message will be moved to the error queue when the dequeue proxy service fails twice.

The JMS Dequeue Proxy Service steps:

Dequeue the JMS Message
Retrieves the Addressing MessageID from the JMS header, $inbound/ctx:transport/ctx:request/tp:headers/jms:JMSCorrelationID/text()
Retrieves the ReplyURL from the body
Replace the header with this one <wsa05:RelatesTo>{$messageId}</wsa05:RelatesTo>
Set the URL with the ReplyURL value, set the URL in the Routing Options activity.
Call the HTTP Business Service.

The HTTP Business Service has a dummy url and uses the callback operation from the WSDL.

Deploy everything to the OSB Server and start SOAPUI so you can test this OSB project.

In SOAPUI you can import the WSDL of the HTTP Proxy Service. I will use the execute operation as test and make a mock service based on the callback operation.