How to call function after completion of async functions inside loop?

Question

I have a forEach loop in NodeJS, iterating over a series of keys, the values of which are then retrieved asynchronously from Redis. Once the loop and retrieval has complete,

Answer 1

No lib is needed. Easy as pie, it's just an async loop. Error handling is omitted. If you need to do a parallel async loop use a counter.

exports.awesomeThings = function(req, res) {
    client.lrange("awesomeThings", 0, -1, function(err, awesomeThings) {
        var len = awesomeThings.length;
        var things = [];
        (function again (i){
            if (i === len){
                //End
                res.send(JSON.stringify(things));
            }else{
                client.hgetall("awesomething:"+awesomeThings[i], function(err, thing) {
                    things.push(thing);

                    //Next item
                    again (i + 1);
                })
            }
        })(0);
});