async_waterfall_in_parallel

async_waterfall_in_parallel.js

var async = require('async');

var products = ['a', 'b', 'c', 'd', 'e'];

var funcs = [];

products.forEach(function(item){
    funcs.push(
        function(callback){
            async.waterfall([
                function(callback){
                    setTimeout(function(){
                        console.log(item);
                        callback(null, item)
                    },500);
                },
                function(arg, callback){
                    console.log(arg);

                    callback(null)
                },
                function(callback){
                    console.log(item);
                    callback(null);
                }
            ], function(err, result){
                callback(null);
            });
        }
    )
});


async.waterfall(funcs,
    function(err, results) {
    console.log(arguments);
});