How to use Random Variables in JMS Selector with JMeter JMS Subscriber

Question

Has any one succeeded in using JMeter Random variable in JMS Selector with JMeter JMS Subscriber for ActiveMQ.

So far I tried to use like below for Random variables but no luck.

JMSCorrelationID ='${msgCorrelation_ID}'

Above selector is working if msgCorrelation_ID is defined as UDV but I need to use Random values per threads.

Answer 1

How do you set your msgCorrelation_ID? What value does Debug Sampler report?

As a solution I can suggest straightforward way of explicit generation of msgCorrelation_ID variable.

Add a Beanshell Pre Processor to your request configured as follows:

Parameters: ${__RandomString(10,abcdefghijklmnopqrstuvwxyz0123456789,)}

Script: vars.put("msgCorrelation_ID", Parameters);

This will populate msgCorrelation_ID variable with random alphanumeric string of 10 characters. You will be able to refer to it where required as ${msgCorrelation_ID} or ${__V(msgCorrelation_ID)}

References:

• __randomString() function documentation
• How to use BeanShell: JMeter's favorite built-in component guide on Beanshell scripting for Apache JMeter

Answer 2

This is because UDV are initialized at test plan startup. Since you have created your variable in Processor, you need to check Setup: Each sample on JMS Subscriber screen, so connection is initialized after ${msgCorrelation_ID} initialization.