Ruby on rails

coding w/ CORE + ADI

getting started

  1. Download the Rails Installer package
  2. Download Sublime Text 2 or RadRails RoR editor
  3. Set up a heroku account to deploy your web app

Why learn Ruby on rails?

  1. Incredibly popular in startup community - Github, Twitter, Hulu, Codecademy were all built with it
  2. Huge number of gems (solutions to common web app problems) for you to use in your web app
  3. Makes a lot of conventional decisions for you so that you don't have to. You can concentrate on building your app

What is ruby?

Ruby is a dynamic, object-oriented programming language made by Yukihiro "Matz" Matsumoto.

"Ruby is designed to make programmers happy" - Matz

what is rails?

Rails is an open-source web framework built for Ruby by David Heinemeier Hansson, aka DHH.


Used to make web applications that follow the MVC (Model View Controller) convention.

ruby basics

  1. "puts" is how you print stuff
  2. > puts "Hello

Ruby


variables
students = ["Don", "Kevin", "Batman"]
students
nil = False (and only nil is false)
"" = true
0 = true
[] = true

strings

 name = "Don Yu"

Building Strings 

 puts "Hello #{name}"

hashes

Series of key-value pairs
 dorm = { name: "Broadway", room: "1004"} puts dorm[:name] puts dorm.name puts dorm[:room] puts dorm.room

functions

 def greet   puts "Greetings!" end

classes

class Greeter  def initialize(name)    @name = name  end
  def greet()    puts "Hello #{@name}"  endend

rails

Create a new barebones rails project 

 $ rails new myappname

Run your rails app

 $ rails server

View the example app

Rails app structure

1. app/ - folder with all of your ruby code for models, views, controllers
2. app/assets - folders where you'll find your HTML, CSS, JavaScript
3. README.rdoc - terse description of Rails
4. Gemfile - all the ruby gems (libraries of code you can just import into your app) that your Rails app uses

Model, View, controller


Lets create models

We will use the scaffolding feature of rails to generate a template model for Users

 $ rails generate scaffold User name:string email:string

Let's also create a model for Dormrooms

 $ rails generate scaffold Dormrooms dorm:string room:string

Now tell our database that we created these new models

 $ bundle exec rake db:migrate

what happened?

  • "rails generate" helps you create template files
  • "rails generate scaffold" creates a model, controller, and view for you!
  • "db:migrate" creates a table for you in your database

rails console

A place to debug your app
 $ rails console > User.create(name: "Jon", email: "jon@jon.com") > jon = User.where(name: "Jon")[0] > jon.name = "Kevin" > jon.save

rails views

You'll notice that rails created a bunch of views for you. Let's concentrate on just
  1. views/layouts/application.html.erb - this is the html that all of your views will have by default
  2. views/dormrooms/index.html.erb - the main page for the "/dormrooms" path

rails configurations

You must edit config/routes.rb to specify what pages open when i.e. to make our Dormrooms page the home page, we can add
 root :to => 'dormrooms#index'

deployment w/ heroku

 $ git init $ git add ./ $ git commit -m "sending all my web app to heroku" $ heroku create $ git push heroku master $ heroku open

Learn more

Ruby
  1. Codecademy
  2. Try Ruby

Examples - RailsApps
Screencasts - Railscast
Books - Ruby on Rails
Heroku - Deploy Rails App

thanks for coming!

Made with Slides.com