RabbitMQ Nodejs.js

var amqpConnectionOptions = {
    host: process.env['RABBITMQ_PORT_5672_TCP_ADDR'], 
    port: 5672, 
    login: 'guest', 
    password: 'guest'
};
var amqpQueueOptions = {
    durable: true,
    autoDelete: false
};
var amqpExchangeName      = 'video';
var amqpQueueName         = 'video-resample';
var serviceName           = 'Video Resample';

var async = require('async');
var amqp = require('amqp');
var fs = require('fs');
var os = require('os');
var exec = require('child_process').exec;
var scales = [240];

async.waterfall([
    /**
     * Creates AMQP Connection
     */
    function(callback) {
        var connection = amqp.createConnection(amqpConnectionOptions, {
            reconnect: true
        });
        connection.on('ready', function(){
            callback(null, {
                connection: connection
            });
        });
    },
    /**
     * Creates Exchanges
     */
    function(context, callback) {
        context.connection.exchange(amqpExchangeName, {
            durable: true,
            type: 'fanout',
            autoDelete: false
        }, function (queue) {
            callback(null, context);
        });
    },
    /**
     * Creates Queues
     */
    function(context, callback) {
        context.connection.queue(amqpQueueName, amqpQueueOptions, function (queue) {
            queue.bind(amqpExchangeName, 'all', function(){
                context.queue = queue;
                callback(null, context);
            });
        });
    }
], function(err, context){
    console.info(serviceName + ' Ready');

    var queue = context.queue;

    queue.subscribe(function(payload){
        var path = JSON.parse((new Buffer(payload.data)).toString());
        console.info(path + ' queued');
        async.eachSeries(scales, function(scale, cb) {
            var outfile = path + '.' + scale + '.mp4';
            var command = 'avconv -i ' + path + ' -strict experimental -acodec aac -b:a 128k -vcodec h264 -flags +aic+mv4 -y -filter:v scale=-1:' + scale + ' ' + outfile;
  	    console.log(command);
            var child = exec(command, [], { 
                env: process.env,
                silent: false
            });
            child.on('error', function(){
                cb(arguments);
            });
            child.stdout.on('data', function(data) {
                 console.log(data.trim());
            });
            child.on('exit', function(){
                console.log('video transcode ' + scale + 'p done');
                cb(null, null);
            });
        }, function(){
            console.info(path + ' processed');
        });
    });

    process.on('exit', function() {
      context.connection.close();
    });
});