[Issue]: NullPointerException when starting a test with a Key Schema File Serializer Config

[pablorodriguez-sngular]

What happened?

I created a Key Schema File Serializer Config, loaded the avro-example.avsc included with the project, and tried to send a Java Request. This same config worked when using a Value Schema File Serializer Config instead.

JMX test plan

KloadGen Version

5.6.7

Relevant log output

java.lang.NullPointerException: Cannot invoke "String.isEmpty()" because the return value of "org.apache.jmeter.threads.JMeterVariables.get(String)" is null
	at com.sngular.kloadgen.sampler.SamplerUtil.configureValueGenerator(SamplerUtil.java:393) ~[kloadgen-5.6.9.jar:?]
	at com.sngular.kloadgen.sampler.KafkaProducerSampler.setupTest(KafkaProducerSampler.java:75) ~[kloadgen-5.6.9.jar:?]
	at org.apache.jmeter.protocol.java.sampler.JavaSampler.sample(JavaSampler.java:194) ~[ApacheJMeter_java.jar:5.6.2]
	at org.apache.jmeter.threads.JMeterThread.doSampling(JMeterThread.java:651) ~[ApacheJMeter_core.jar:5.6.2]
	at org.apache.jmeter.threads.JMeterThread.executeSamplePackage(JMeterThread.java:570) ~[ApacheJMeter_core.jar:5.6.2]
	at org.apache.jmeter.threads.JMeterThread.processSampler(JMeterThread.java:501) [ApacheJMeter_core.jar:5.6.2]
	at org.apache.jmeter.threads.JMeterThread.run(JMeterThread.java:268) [ApacheJMeter_core.jar:5.6.2]
	at java.lang.Thread.run(Thread.java:833) [?:?]

Have you added your JMX Testplan or a replica?

• I have added a JMX testplan

Have you added your Schema or a replica?

• I have added the Schema

[github-actions]

Thank you for collaborating with the project by giving us feedback! In case it applies, it would be helpful if you could attach an example AVRO and an example test plan for us to reproduce the error. Cheers!