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Yevhen Nakonechnyi xab3r

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# Simple JOIN
User.joins(:account) # User -> Account
# Will produce
# SELECT `users`.* FROM `users` INNER JOIN `accounts` ON `accounts`.`user_id` = `users`.`id`
# Complicated JOIN
Trait.joins(:user => :account) # Trait -> User -> Account
# Will produce
# SELECT `traits`.* FROM `traits` INNER JOIN `users` ON `users`.`id` = `traits`.`user_id` INNER JOIN `accounts` ON `accounts`.`user_id` = `users`.`id`

Setting up and installing rbenv, ruby-build, rubies, rbenv-gemset, and bundler

This guide enables you to install (ruby-build) and use (rbenv) multiple versions of ruby, isolate project gems (gemsets and/or bundler), and automatically use appropriate combinations of rubies and gems.

TL;DR Demo

# Ensure system is in ship-shape.

aptitude install git zsh libssl-dev zlib1g-dev libreadline-dev libyaml-dev




=Clicking links and buttons=
click_link('Link Text')
click('Link Text') # Click either a link or a button
click('Button Value')
# Permissions cheatsheet
`chmod [a]bcd`
* bit a — sticky:1/setgid:2/setuid:4 (optional, default: 0)
* bit b — owner | x:1/w:2/r:4 - xw:3/xr:5/wr:6/xwr:7
* bit c — group | x:1/w:2/r:4 - xw:3/xr:5/wr:6/xwr:7
* bit d — everyone | x:1/w:2/r:4 - xw:3/xr:5/wr:6/xwr:7
note: only file/dir owner can chmod it

In Rails 3

NOTE: This post now lives (and kept up to date) on my blog:

If you add a dir directly under app/

Do nothing. All files in this dir are eager loaded in production and lazy loaded in development by default.

If you add a dir under app/something/

@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
response.should render_template(:index)
response.should redirect_to(movies_path)

Render and Redirect

The normal controller/view flow is to display a view template corresponding to the current controller action, but sometimes we want to change that. We use render in a controller when we want to respond within the current request, and redirect_to when we want to spawn a new request.


The render method is very overloaded in Rails. Most developers encounter it within the view template, using render :partial => 'form' or render @post.comments, but here we'll focus on usage within the controller.


class PagesController < ApplicationController
before_filter :login_required, :except => [ :show ]
# GET /pages
# GET /pages.xml
def index
@pages = Page.find(:all)
respond_to do |format|
format.html # index.html.erb
module AuthHelper
def http_login
user = 'username'
pw = 'password'
request.env['HTTP_AUTHORIZATION'] = ActionController::HttpAuthentication::Basic.encode_credentials(user,pw)
module AuthRequestHelper