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###Let's install Vagrant###

Install VirtualBox: https://www.virtualbox.org/
Install Vagrant: http://vagrantup.com/

###Select a Vagrant Box from https://vagrantcloud.com###

#add it to your list of boxes
vagrant box add hashicorp/precise32
#create a new folder for your project &amp; init vagrant

###SSH into a remote machine###

ssh [email protected]
#or by ip address
ssh [email protected]

exit: exit ###Install Something###

#If it's a new server, update apt-get first thing

##what are generators##

They're pausable functions, pausable iterable functions, to be more precise
They're defined with the *
every time you yield a value, the function pauses until .next(modifiedYieldValue) is called

var myGen = function*() {
  var one = yield 1;
  var two = yield 2;
  var three = yield 3;
 console.log(one, two, three);

###Doing Express.js Async With Generators###

Using Co library, run generators as responses by wrapping Co and adding an extra function to handle errors

Because Co always runs the last argument as a callback...so it would always runs next() by default
This function only runs next if there's an error

//assign this to the Co module somewhere in application bootstrapping, 
//so you can do var ce = require('co').coExpress in each router file
co.coExpress = (generator) => {
  return (...args) => {

##The Good, The Bad, & The Ugly Ways of handling Async Operations With Javascript## #####Callbacks < Promises < Generators#####

###An Example: 5 in-sequence Async Operations### (also see parallel-sequence example: https://gist.github.com/willrstern/af3a3308fc5864cf48f8)

###The Ugly Way: Callbacks### After each function takes place, handle any errors & do the next thing - It's easy to walk through the code and understand what's going on...but it's ugly as sin

##Example Task: Make 2 parallel (simultaneous) async calls, then one async call when they've resolved##

##The Good Way: Promises##

//with bluebird library
var parallelCalls = [
  getUrl('/api/profile'),
  getUrl('/api/accounts')
];
//spread is like .then(), except it apply()s the array of responses as individual arguments

Here's all you have to do to add clustering to your node.js application.

save this code as cluster.js, and run cluster.js instead of server.js (or /bin/www, or whatever it's called for your project)
the only line you'll need to change is the last line - it needs to point to the location of your server.js file

var cluster = require('cluster');

if (cluster.isMaster) {
  // Count the machine's CPUs
 var cpuCount = require('os').cpus().length;

(wherever it says url.com, use your server's domain or IP)

Login to new server as root, then add a deploy user

sudo useradd --create-home -s /bin/bash deploy
sudo adduser deploy sudo
sudo passwd deploy

And Update the new password

##Setup your server (this would ideally be done with automated provisioning)

add a deploy user with password-less ssh see this gist
install forever npm install -g forever

##Install flightplan

npm install -g flightplan
in your project folder npm install flightplan --save-dev
create a flightplan.js file

	upstream project {
	server 22.22.22.2:3000;
	server 22.22.22.3:3000;
	server 22.22.22.5:3000;
	}

	server {
	listen 80;

	location / {