My netflow module for Node.JS has been updated. Now it support more NetFlow versions – like NetFlow ver 1, ver 5, ver 7 and ver 9. Also it has been modified to be able to be used as Event Generator (instead of doing callbacks). Now you can do as well (the old model is still supported):

Collector({port: 3000}).on('data',function(flow) {
    console.log(flow);
});

Additionally, the module now supports and decode option templates and option data flows for NetFlow v9.