NodeJS : How to debug “EventEmitter memory leak detected. 11 listeners added”

Question

How can I debug my application which throw this error:

(node) warning: possible EventEmitter memory leak detected. 11 listeners added. Use emitter.setMaxList         


        

Answer 1

I tried to prototype the EventEmitter for adding log messages into addListener but i could not get it working

To hook addListener you can do something like this:

// on the first line of your main script
var events = require("events"),
    EventEmitter = events.EventEmitter;

var originalAddListener = EventEmitter.prototype.addListener;
EventEmitter.prototype.addListener = function (type, listener) {
    if (this.listenerCount(this, type) >= 10) {
        // TODO: PLACE YOUR CODE FOR DEBUGGING HERE
    }
    originalAddListener.apply(this, arguments);
}