Dmitriy Ivliev moofkit

Setup

Replace IRB with Pry (in your Gemfile) and Byebug with pry-byebug.

gem 'pry-rails', group: [:development, :test]
gem 'pry-byebug', group: [:development, :test]

Using PRY

Studying for a Tech Interview Sucks, so Here's a Cheat Sheet to Help

This list is meant to be a both a quick guide and reference for further research into these topics. It's basically a summary of that comp sci course you never took or forgot about, so there's no way it can cover everything in depth. It also will be available as a gist on Github for everyone to edit and add to.

Data Structure Basics

###Array ####Definition:

Stores data elements based on an sequential, most commonly 0 based, index.
Based on tuples from set theory.

When should you use DateTime and when should you use Time?

It's a common misconception that [William Shakespeare][1] and [Miguel de Cervantes][2] died on the same day in history - so much so that UNESCO named April 23 as [World Book Day because of this fact][3]. However because England hadn't yet adopted [Gregorian Calendar Reform][4] (and wouldn't until [1752][5]) their deaths are actually 10 days apart. Since Ruby's Time class implements a [proleptic Gregorian calendar][6] and has no concept of calendar reform then there's no way to express this. This is where DateTime steps in:

>> shakespeare = DateTime.iso8601('1616-04-23', Date::ENGLAND)
=> Tue, 23 Apr 1616 00:00:00 +0000
>> cervantes = DateTime.iso8601('1616-04-23', Date::ITALY)
=> Sat, 23 Apr 1616 00:00:00 +0000

	=Navigating=
	visit('/projects')
	visit(post_comments_path(post))

	=Clicking links and buttons=
	click_link('id-of-link')
	click_link('Link Text')
	click_button('Save')
	click('Link Text') # Click either a link or a button
	click('Button Value')

	#Model

	@user.should have(1).error_on(:username) # Checks whether there is an error in username
	@user.errors[:username].should include("can't be blank") # check for the error message

	#Rendering
	response.should render_template(:index)

	#Redirecting
	response.should redirect_to(movies_path)

	### Nginx ###
	check process nginx with pidfile /run/nginx.pid
	start program = "/etc/init.d/nginx start"
	stop program = "/etc/init.d/nginx stop"
	if cpu > 60% for 2 cycles then alert
	if cpu > 80% for 5 cycles then restart
	if memory usage > 80% for 5 cycles then restart
	if failed host 127.0.0.1 port 80 protocol http
	then restart
	if 3 restarts within 5 cycles then timeout