[WSO2 ESB] How to Use Property Mediator.

Prerequisites.

WSO2 ESB.

In this post I'm going to demonstrate how to use the ESB property mediator.

The property mediator can use as a variable in programming language. We can set a value in the property mediator and we can use it by property name in other operations of the code.

In the following example proxy , I added a property called “CompanyName” and used it inside the log mediator .

Steps to add a Property Mediator.

Go to design view of your created proxy service.

Then click on Add Child → Core → Property

  Then you will get a property mediator setting console as shown in below figure.

Name : A name for the property.

Action : Using this we can set or remove a property from the message context.

Set Action as : If you are setting a static value for the property then you need select the Value option . If you are setting a dynamic value for the property then you need to select Expression option.

Type: Data type of the property. (String, Boolean, Integer, float, long etc.)

Value : value of the property. If you are setting a dynamic value for the property then you need to use the Xpath expression here.

Ex: If you need to set the Id as a property from following XML response,

<project>

<id>10</id>

<name>WSO2 Governance Registry</name>

</project>

then you need to set the following Xpath as the value.

//project/id

Pattern: We can use regular expression here to evaluate value or expression of the property.

After adding the property then you can use it by property name in other operations.

You can retrieve the property value by using 'get-property('Name of the Property')'.

In the following example proxy I used the above property (CompanyName) inside the log mediator.

Then the output is as shown below.

 Proxy

       
<proxy name="Demo" startonload="true" statistics="disable" trace="disable" transports="https,http" xmlns="http://ws.apache.org/ns/synapse">
   <target>
      <insequence>
         <property name="CompanyName" scope="default" type="STRING" value="WSO2">
         <log>
            <property expression="get-property('CompanyName')" name="Value_Of_Property">
         </property></log>
      </property></insequence>
   </target>
   <description>
</description></proxy>

         
       
 

References [1].https://docs.wso2.com/display/ESB481/Property+Mediator