Filtering in WSO2 - esb

Question

I want to build one proxy that:
1. Call Service that do Authorize and give result OK or Fail (1st Service)
2. If Result ‘OK’ then call a Service
The Problem is, when The 1st Service give back the Message :
<?xml version='1.0' encoding='utf-8'?>
<soapenv:Envelope xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/">
<soapenv:Body>
<result>
<status>OK</status>
<message></message>
</result>
</soapenv:Body>
</soapenv:Envelope>
And I give “filtering” at Out Sequence. Here is the XML :
<proxy xmlns="http://ws.apache.org/ns/synapse" name="TestProxy" transports="https,http" statistics="disable" trace="enable" startOnLoad="true">
<target endpoint="AuthorizationService">
<outSequence>
<log level="full" />
<filter xpath="/result/status='OK'">
<then>
<send>
<endpoint>
<address uri="http://192.168.1.140:8080/axis2/services/TaskService.TaskServiceHttpEndpoint/getTask" />
</endpoint>
</send>
</then>
<else>
<makefault version="soap11">
<code xmlns:soap11Env="http://schemas.xmlsoap.org/soap/envelope/" value="soap11Env:VersionMismatch" />
<reason value="1" />
<role>2</role>
<detail>3</detail>
</makefault>
</else>
</filter>
<log level="full" />
</outSequence>
</target>
</proxy>
When I run my Application, the ESB always give the message :
16:08:59,358 [-] [HttpClientWorker-4] INFO Start : Log mediator
16:08:59,361 [-] [HttpClientWorker-4] INFO To: http://www.w3.org/2005/08/addressing/anonymous, WSAction: , SOAPAction: , MessageID: urn:uuid:0bc33821-c4f1-448e-a7dc-be4194be8e99, Direction: response, Envelope: <?xml version='1.0' encoding='utf-8'?><soapenv:Envelope xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/"><soapenv:Body><result><status>OK</status><message></message></result></soapenv:Body></soapenv:Envelope>
16:08:59,361 [-] [HttpClientWorker-4] INFO End : Log mediator
16:08:59,361 [-] [HttpClientWorker-4] INFO Start : Filter mediator
16:08:59,361 [-] [HttpClientWorker-4] INFO XPath expression : /result/status='OK' evaluates to false - executing the else path child mediators
Seems like the condition of the filtering is always false.What is the correct statement for the XPath in the filter?

Answer 1

Your proxy configuration should be look as follows
<proxy xmlns="http://ws.apache.org/ns/synapse" name="TestProxy" transports="https,http" statistics="disable" trace="enable" startOnLoad="true">
<target endpoint="AuthorizationService">
<outSequence>
<log level="full"/>
<filter source="/result/status" regex="ok">
<then>
<send>
<endpoint>
<address uri="http://192.168.1.140:8080/axis2/services/TaskService.TaskServiceHttpEndpoint/getTask"/>
</endpoint>
</send>
</then>
<else>
<makefault version="soap11">
<code xmlns:soap11Env="http://schemas.xmlsoap.org/soap/envelope/" value="soap11Env:VersionMismatch"/>
<reason value="1"/>
<role>2</role>
<detail>3</detail>
</makefault>
<send/>
</else>
</filter>
</outSequence>
</target>
<description></description>
</proxy>

Answer 2

It seems that you may have given a wrong xpath expression. You can't give an xpath and a boolean expression both for the xpath value, i.e. it can't be "/result/status='OK'", but has to be "/result/status". Then, according to your sequence, it would fire the section after then, if this element is present. Since, you need to evaluate a boolean condition as well based on the xpath, I'll present an alternative based on the switch mediator (Same can be done for the filter by setting a property):
<proxy xmlns="http://ws.apache.org/ns/synapse" name="TestProxy" transports="https,http" statistics="disable" trace="enable" startOnLoad="true">
<target endpoint="AuthorizationService">
<outSequence>
<log level="full" />
<switch source="//result/status">
<case regex="OK">
<send>
<endpoint>
<address uri="http://192.168.1.140:8080/axis2/services/TaskService.TaskServiceHttpEndpoint/getTask" />
</endpoint>
</send>
</case>
<default>
<makefault version="soap11">
<code xmlns:soap11Env="http://schemas.xmlsoap.org/soap/envelope/" value="soap11Env:VersionMismatch" />
<reason value="1" />
<role>2</role>
<detail>3</detail>
</makefault>
</default>
</switch>
<log level="full" />
</outSequence>
</target>
</proxy>