Nate Delage ndelage

Getting Your Rails App Ready for the Major League

Note: This doc is aimed towards hosting on Heroku. Many of these tips apply to any Rails host, but the details won't be the same.

Heroku is incredibly convenient but the defaults aren't entirely appropriate as web apps grow. This doc provides some tips for improving your app's performance, acting responsible with your data and handling the kind of issues you only experience in production.

Postgres Backups

A poorly written DB migration or slip up in console can be all it takes to loose data in production. Heroku offers a free backup add-on for Postgres databases. As part of the free plan Heroku offers either weekly or monthly backups. Weekly backups are the default.

Web App Performance

Back End

N+1

  @users = User.all.includes(:profile) # SELECT * from users

Excessive joins/subselects or exta queries

DBC Book Recommendations 2/21/14

Nate "Dirty Lobster"

Abi "Knee Thrust" Noda

Easy Bake Artisanal Bread

This recipe uses volumetric measurements, which are the pits. We should really be measuring our ingredients by weight. Try this recipe for now, but you should go buy a scale

Ingredients

4 cups bread flour (500g)
1 tsp instant yeast (7.5g)
2 tsp salt (10g)
1 1/2 cups water (350g)

	##
	## RESTful routes for 2 resources:
	# 1) Sessions
	# 2) Bands
	#
	# Note: In order to use the 'other' HTTP verbs (put & delete) you need to enable the
	# method_override feature of Sinatra.
	#
	# (in config/environment.rb)
	# config do

	var elems = $('a');


	// WITHOUT THE IIFE
	//
	// In the following example, the alert text "I am i", will always
	// print '3' because that's the last value for i (after the loop
	// finishes). If we want to retain the value of i when we bind
	// the click handler, we can use an IIFE to save the value of i
	// in the IIFE's execution context

	// How many globals?
	function Person(name) {
	this.name = name;
	}

	function greeting(person) {
	console.log("Hello " + person.name);
	}

	var roger = new Person("Roger");

	$(document).ready(function() {
	$("#quote_body").on('keyup', function() {
	var currentCount = $(this).val().length;
	$("#count").html(currentCount);

	if(currentCount > 20) {
	$("#body-length-status").addClass("over-limit");
	} else {
	$("#body-length-status").removeClass("over-limit");
	}

	<html>
	<head>
	<script src="http://cdnjs.cloudflare.com/ajax/libs/jquery/2.1.0/jquery.min.js"></script>
	<script src="http://cdnjs.cloudflare.com/ajax/libs/underscore.js/1.6.0/underscore-min.js"></script>
	<script src="http://cdnjs.cloudflare.com/ajax/libs/backbone.js/1.1.2/backbone-min.js"></script>

	<style>
	.album {
	float: left;
	margin: 20px;

	require 'active_record'

	def setup
	ActiveRecord::Base.establish_connection adapter: "sqlite3", database: ":memory:"
	end

	def generate_migrations
	ActiveRecord::Migration.create_table :hotels do \|t\|
	t.string :name
	t.integer :room_count