Rails Reference

Table of Contents

• Startup Rails App
• Gems
• RSpec
• Factory Girl
• User Authentication
• Show All Routes
• Make a Model
• Make a Controller
• Add & Remove Columns from Migrations
• Resource Routing
• Callbacks & Filters
• Heroku Deployment

Startup Rails App

Do this after forking from master, make sure you're on your own branch.

1. cd into your 'project-forks' folder
2. echo 'ProjectName' > PROJECTFOLDER/.ruby-gemset
   • ex) echo 'TaskListRails' > C3Projects--TaskListRails/.ruby-gemset
3. echo '2.2.2' > PROJECTFOLDER/.ruby-version
   • ex) echo '2.2.2' > C3Projects--TaskListRails/.ruby-version
4. cd in to project folder (wrappers happen...)
5. rvm gemset list (yes it's on the gemset we just created)
6. gem install bundler
7. gem install rails --no-ri --no-rdoc
8. git add .
9. git commit -m "Created gemset."
10. rails new . -T
11. git add .
12. git commit -m "fresh Rails install"
13. open and edit Gemfile with gems, save!
14. bundle install --without production

Gems

• better errors (in group :development):

# Better Errors for debugging
gem 'better_errors'
gem 'binding_of_caller'

• Pry Rails (in group :development): gem 'pry-rails'
• RSpec (in test section): gem 'rspec-rails'
  • rails generate rspec:install
  • Add --format doc to .rspec file to see words
• Factory Girl (in group :test): gem 'factory_girl_rails', '~> 4.0'
  • Add to config block in spec_helper.rb config.include FactoryGirl::Syntax::Methods and require 'factory_girl' to top of file
  • Create file to define factories: touch spec/factories.rb
• SimpleCov (in group :test): gem 'simplecov', require: false
  • add to spec/spec_helper.rb

  require 'simplecov'
  SimpleCov.start 'rails'

  • add coverage to .gitignore
• Bootstrap: gem 'bootstrap-sass'
  • create custom.css.scss file for your own custom CSS
  • add to custom.css.scss

  @import "bootstrap-sprockets";
  @import "bootstrap";

  • add to app/assets/javascripts/application.js

  //= require jquery
  //= require bootstrap-sprockets
  

  • restart rails server if already open
• bcrypt (click link for more info): gem 'bcrypt'
  • add has_secure_password to User model associations
• CarrierWave: add gem 'mini_magick' BEFORE gem 'carrierwave'
  • If imagemagick is not installed: brew install imagemagick
  • rails g uploader image, image can be called anything: avatar, cover_art, etc.
  • rails g migration adds_image_to_albums, to add a reference column (for the image) to database
  • Add add_column :albums, :image, :string to new migration file.
  • rake db:migrate
  • Open Album Model and add # Mounted Objects -----------------------
  • Add mount_uploader :image, ImageUploader under "Mounted Objects"
  • Go to uploaders/image_uploader.rb, uncomment line 7 include CarrierWave::MiniMagick
    • line 35 block allows you to resize image as it's uploaded, uncomment to resize images to thumbnails (50px by 50px)
    • add another block to create another version of image transformation (if desired)
    • uncomment file extensions on line 41 to allow only certain file ext. (jpg, png, gif)
  • Add :image to albums_params in AlbumsController
  • Able to use these methods .image_url and .image_url(:thumb)
  • Add public/uploads/ to .gitignore
• HTTParty: gem 'httparty'
  • require 'HTTParty' wherever you're using it
  • Example:
    • weather_url = "http://api.openweathermap.org/data/2.5/weather?q=Seattle&units=imperial"
    • r = HTTParty.get(weather_url)
• OmniAuth
  • Note different providers have their own gems they maintain and one can use:

  # OmniAuth Gems
  gem 'omniauth'
  gem 'omniauth-github'

  • Go to GitHub to register new application (in profile settings --> applications --> Developer Applications -- Register New Application)
  • Authorization callback URL: http://localhost:3000/auth/github/callback
  • Follow remaining steps here: OmniAuth
• VCR (in group :test): gem 'vcr'
  • VCR github
  • Used to test API calls in RSpec
• if deploying to heroku: move sqlite3 gem to development, then add

group :production do
    gem 'pg'
end

Show All Routes

rake routes

Make a Model

rails generate model modelname columnname1:type columnname2:type columname3:type

• Example: rails generate model student name:string cohort:string birthday:datetime

Make a Controller

rails generate controller controller_name

• Example: rails generate controller tasks
• convention says controller name is plural
  • i.e. ClientsController preferred over ClientController

Add Column

rails generate migration add_columnname_to_tablename column:type

• Example: rails generate migration add_personid_to_tasks personid:integer

Remove Column

rails generate migration remove_columnname_from_tablename column:type

• Example: rails generate migration remove_personalid_from_tasks personid:integer

Resource Routing

All routes

resources :labels

Only certain routes

resources :labels, only: [:index, :show]

All routes EXCEPT

resources :labels, except: [:index, :show]

Taking a Block

resources :labels do
  # 8 more routes generated
  resources :albums
end

Nesting Routes

Shouldn't nest more than one deep

  resources :labels do
    resources :albums
    resources :artists do
      resources :albums, only: [:index, :show]
    end
  end

Collection Routes

resources :albums, only: [:index, :show] do
  collection do
    get 'released/:year', action: 'by_year', as: 'by_year'
  end
end

• get 'released/:year' => 'albums#by_year'
• as: 'bye_year' allows for by_year_albums_path for linking
• also have by_year_albums_url for linking offsite

RSpec

1. Add gem to development section gem 'rspec-rails', '~> 3.0'
2. bundle
3. rails generate rspec:install
4. Add --format doc to .rspec file to see words

Model Specs (example)

1. To generate tests for Album model rails generate rspec:model Album
2. Go to spec -> model -> album_spec to edit specs
3. Edit specs
4. To run, use rspec command in terminal

For Controller (example)

1. To generate tests for Albums controllerrails generate rspec:controller albums
2. Go to spec -> controllers -> album_controller_spec to edit specs
3. Edit specs
4. To run, use rspec command in terminal

To run a spec for a specific folder rspec folder/path For example, rspec spec/controllers

Heroku Deployment

Make sure your sqlite3 gem is under development group and add gem 'pg' is in production group

1. Make sure current project is committed, git commit -m "Your message here"
2. heroku create NAMEOFSITE
   • ex: heroku create myapp will create myapp.herokuapp.com
3. git push heroku branch:master
4. heroku run rake db:migrate
5. heroku run rake db:seed

If db:drop doesn't work

1. heroku pg:reset DATABASE
2. heroku run rake db:migrate
3. heroku run rake db:seed
4. heroku restart

User Authentication

1. add gem 'bcrypt'
2. bundle
3. rails g model User name:string email:string password_digest:string
4. Add has_secure_password to User model (-> app/model/user.rb)
   • Methods available for models w/ 'password_digest defined': user.password and user.password_confirmation
   • will not save password if these two values don't match
   • user.authenticate allows one to check if password matches existing stored password_digest
   • User.find_by(name: 'david').try(:authenticate, 'newd00les')
5. Add home_controller.rb and root 'home#index' to show a home page
6. rails g controller sessions
7. Add new, create, and destroy methods to SessionsController.

Routes

root 'home#index'
resources :users
resources :sessions, :only => [:new, :create, :destroy]

Callbacks

Callbacks allow you to trigger logic before or after an alteration of an object's state.

• Example: before_validation :ensure_login_has_a_value
• Example: after_validation :set_location, on: [ :create, :update ]

Filters

Filters are methods that are run before, after or "around" a controller action.

• Example: before_action :require_login
• Example: skip_before_action :require_login, only: [:new, :create]
• Example: around_action :wrap_in_transaction, only: :show

FactoryGirl

• Defining a factory within Book model:

FactoryGirl.define do
  factory :book do
    name "House of Leaves"
    author "Mark Z. Danielewski"
    description "House of Leaves is the debut novel by the American author Mark Z. Danielewski, published by Pantheon Books. The novel quickly became a bestseller following its release on March 7, 2000. It was followed by a companion piece, The Whalestoe Letters"
  end
end

• Using in testing:

describe Book do

  describe "validations" do
    it "is valid" do
      expect(create(:book)).to be_valid
    end

    it "is invalid without a name" do
      expect(build(:book, name: nil)).to be_invalid
    end

  end
end

• old way:
  • @book = Book.create(name: "", author: "", description: "")
• factory way:
  • @book = create(:book)
  • 10.times { create(:book) }
  • @unsaved_book = build(:book)