WDI Darth Vader

Ruby on Rails

Getting Started

Workflow Earth, by Tim Rourke

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1. Create & open a new Rails project

Note: If you do not have Rails installed, you must install the gem: gem install rails!

This is a step-by-step guide to creating a new Rails application. Let's get started! To create a new rails app, you use the following syntax:

  • rails new app_name -d postgresql -T

Where app_name is the name of your application. For example, to create an app called Coffee_Shop, I would enter the following into my terminal: rails new Coffee_Shop

The -d postgresql tells rails to configure the application to use postgres

The -T tells rails to ommit including the default rails testing framework

This will create a new Ruby on Rails application in a new desdecent folder named after my app's name in the rails new command. Enter ls to see the folder and then cd your_app_name to move into your new app. To open your new Rails project, in atom, enter the following command: atom .

2. Updating your Gemfile

Locate your application's Gemfile. Inside of it, you will comment out the following gem(s):

  • gem 'coffee-rails', '~> 4.1.0'

You will also add the following gem(s):

  • gem 'rspec-rails'

Once you've edited your Gemfile, it is time to feel the ground shake and bundle!

3. Working with your project locally

  • To view your project in the browser you will need to run a server (similar to rack).
  • In your terminal, enter rails server
  • Unlike rack, your project will be served at: http://localhost:3000/

  • Note the difference in ports: 9292 vs 3000

  • To view your project in the console you will run rails console

  • From this console, you can test out your models, for example.

4. Generating Models

To generate a model for your project, you can run the following command:

  • rails generate model Name product_name:string description:text

Note: because we strive for efficiency, we'r going to start calling our rake commands in the bin/ directory inside of our project!!!

5. Database Setup/Creation

To automatically generate SQL database tables based on your models, you can run the following command:

  • bin/rake db:create

To run any changes in your migration scripts, you must run:

  • bin/rake db:migrate

Finally, to create test entries for RSpec tests, you must run the following command:

  • bin/rake db:test:prepare

6. Creating Routes/Controllers

Create a controller to go along with our model.

  • bin/rails generate controller roasts index show edit new

Where rails generate controller specifies that we're creating a new controller. roasts is the name. index show edit new are the actions to be generated in our controller.

We can also delete actions:

  • bin/rails d controller roasts index show edit new

  • bin/rake routes returns a list of routes in your Rails project.

7. Install RSpec in your Project

Once you have included rspec in your project, you may generate unit test specs using the following command(s) in your termnial:

rails generate rspec:install

To run your tests in the command line:

  • bin/rake spec

8. Example RSpec Unit Test

require 'rails_helper'

RSpec.describe Object, type: :model do

    describe 'given an object' do
        before do
            @object = Object.new()
        end

        describe '#to_s' do
            it 'returns an object is an "Object"' do
                expectation = @object.to_s # should return 'Object'
                actual = 'Object'
                expect(expectation).to eq(actual)
            end
        end

    end

end

Misc

  • In RSpec, . is a class method and # is an instance method

Further Reading