Jmeter | Groovy functions aren't working

Question

I am currently following the 'Blazemeter Jmeter Pro' certification training and while working on an exercise, I noticed that for some reason, the groovy functions aren't working for me. Let me show you:

I wrote a couple of functions in a dummy sampler like this:

Then when I ran, I got the username, password and time as expected

but the token response is just empty.

I got no clue and am just dumbstruck with this issue. This happened to me with the other lecture videos as well. I am guessing that this is a configuration issue. Any help is appreciated.

P.S. This is the function mentioned in the picture:

{"token": ${__groovy(new StringBuilder().append(${counter_variable}).append(${password_variable}).append(${time_variable}),)}}

Answer 1

Don't ever inline JMeter Functions or Variables into Groovy scripts, if you want to access the variable value use vars shorthand instead, it stands for JMeterVariables class instance and provides read/write access to all the JMeter Variables in the current thread scope.

You need to change this:

{"token": ${__groovy(new StringBuilder().append(${counter_variable}).append(${password_variable}).append(${time_variable}),)}}

to this:

{ "token" : ${__groovy(new StringBuilder().append(vars.get('counter_variable')).append(vars.get('password_variable')).append(vars.get('time_variable')).toString(),)} }

More information: Top 8 JMeter Java Classes You Should Be Using with Groovy

Answer 2

Okay! So I have figured it out the reason by just writing it over here Damn!

Just posting it here so that someone might find it useful -

Apparently I had added a couple of randomized alphabets along with numbers in the password variable which gets appended to the token variable.

Whenever an alphabet comes into the string, it doesn't work and returns a blank line.

I changed it to just numbers like this - and voila!