README.md

Session 1 - Getting Started with Rails

The first sesssion is all about getting started with Rails.

Session 1 - Getting Started with Rails (Slides)

We will create a website with two pages - a Home Page and an About Me page.

The home page just contains a heading with text "Hello, World!" whereas About Me page is more detailed, with the following elements:

• An heading with your name.
• An paragraph with your bio.
• An ordered list with four of your favorite hobbies.

For example, @abhishekkumar2718's website looks like the following:

The aim of session 1 is to become familiar with Rails and collaborating with others through Git. We will be building more impressive websites by the end of Bootcamp.

Steps

• Install Ruby and Rails

• Set Up Local Workplace

Create a Rails Project

• Create a new Rails project hello_world in the directory session_1:

cd session_1
rails new hello_world --skip-git
cd hello_world

The command rails new initialises a Rails project. We have passed the flag --skip-git to avoid initializing Git again as we are already within a Git repository.

• Create a database and run the migrations using:

rails db:create
rails db:migrate

A database is a software to store and organize data. With databases, you don't have to worry how data is stored and can focus on the rails application instead. A database migration modifies the database schema i.e. tables, columns and entries in the database.

• Run the rails server using below command and go to http://localhost:3000/.

rails server

You should see Yay! You're on Rails!:

Customize Your Website

• Generate a new controller PageController with actions root and about_me:

rails generate controller Page root about_me

A controller is responsible for making sense of request and producing the appropriate output. It acts as a middleman between the Data (Model) and Presentation (View). Controllers are stored in app/controllers directory.

A generator creates and fills out files with default code, making your job easier. For example, the above command creates a controller PagesController, creates view files root.html.erb and about_me.html.erb and modifies the routes file - with a single simple instruction.

• Edit the routes file (config/routes.rb) as follow:

Rails.application.routes.draw do
  get '/', to: 'page#root'
  get 'about_me', to: 'page#about_me'
end

The routes file specifies the URLs that are recognized by the application. In the above example, we can visit https://localhost:3000/about_me but not https://localhost:3000/contact as it is not specified in the routes file.

• Edit the view files (app/views/page/root.html.erb, app/views/page/about_me.html.erb).

A View displays data in a desired format. As we are building web pages, the desired format is HTML. The view files are stored in app/views directory.

• Reload the pages http://localhost:3000 and http://localhost:3000/about_me (on your web browser) to inspect your changes.

• Copy the test file from session_1 directory to hello_world/test/controllers:

cp page_controller_test.rb hello_world/test/controllers

Since we are creating a new application, the test file cannot exist yet and must be copied into the application. In the later exercises, we will no longer need to copy tests.

• Execute the test suite to ensure the page works as expected.

rails test

• If the test fails, check the view files and debug the application.

• Once the test works locally, submit your changes.