This is a sample project using kafka and drools
for installation you must installing kafka and creating two topics with these names "quickstart-events" and "payment-result" then you can build project with mvn package and run it.
You can call rest service on the address : ${your server address}/sendMessage with POST method and inputs: cardNo, amount, monthlyAmount the application will be validate this data againts drools rule and put the result on "payment-result" topic on kafka