JMeter : Debug Sampler , JSR223 Sampler , Reading a text file content

Create a text file and save in JMeter/bin folder

Select Groovy in drop down, we have other scripting languages support also

import org.apache.jmeter.util.JMeterUtils;
String fileContents = new File('./nameOfFileToRead.txt').getText('UTF-8');
vars.put("your_fileContentsVariableName",fileContents);
log.info("Message:" + vars.get("your_fileContentsVariableName"));

Add a Debug Sampler, to get all the JMeter variables used in the test plan. Set all dropdowns as true.

 In the Debug Sanpler, Response Data , we can see the text file content.

Also open the JMeter console. The same is displayed here also. Because we have used the following line.

log.info("Message:" + vars.get("your_fileContentsVariableName"));