Ruby on Rails
Switch branches/tags
Clone or download
y-yagi Merge pull request #34243 from deivid-rodriguez/fix_generated_gemfile…

Fix generated Gemfile missing gems on jruby
Latest commit 885ab06 Oct 18, 2018
Failed to load latest commit information.
.github Remove some autolabeling globs Oct 5, 2018
actioncable fix broken link in Action Cable guides and readme [ci skip] Oct 8, 2018
actionmailer Fix tests on Mail 2.7.1 Oct 14, 2018
actionpack Fix `ActionController::Parameters#each_value` and add changelog entry… Oct 15, 2018
actionview Add allocations to template renderer subscription Oct 10, 2018
activejob Clarify docs of `ActiveJob::TestHelper` [ci skip] Oct 15, 2018
activemodel Improve model attribute accessor method names for backtraces Oct 12, 2018
activerecord Don't expose internal `get_value`/`set_value` methods Oct 17, 2018
activestorage Point to requiring the ASt engine in the installation instructions [c… Oct 8, 2018
activesupport Refactor Chars#reverse and Chars#grapheme_length Oct 16, 2018
ci Use the same option for create database statements between Raketask a… Sep 26, 2018
guides Remove and flip `index: true` for `references` in the doc [ci skip] Oct 17, 2018
railties Fix generated Gemfile missing gems on jruby Oct 17, 2018
tasks Fix rubocop offenses Aug 15, 2018
tools Use frozen string literal in tools/ Aug 13, 2017
.codeclimate.yml Bump RuboCop to 0.58.2 Jul 26, 2018
.gitattributes adds .gitattributes to enable Ruby-awareness Mar 16, 2016
.gitignore Make Webpacker the default JavaScript compiler for Rails 6 (#33079) Oct 1, 2018
.rubocop.yml Skip node_modules dir in the rubocop check Oct 5, 2018
.travis.yml Include test gems in CI Oct 11, 2018
.yardopts Let YARD document the railties gem Sep 10, 2010
.yarnrc Make Webpacker the default JavaScript compiler for Rails 6 (#33079) Oct 1, 2018
Brewfile [ci skip] Add ImageMagick to Brewfile Aug 22, 2018 Update CoC to change a history of updates URL [ci skip] Apr 19, 2018 Remove html tag making markdown misrender [ci skip] Jun 6, 2017
Gemfile Add test retries for railties Oct 11, 2018
Gemfile.lock Bump mail to `2.7.1` Oct 13, 2018
MIT-LICENSE Bump license years for 2018 Dec 31, 2017
RAILS_VERSION Start Rails 6.0 development!!! Jan 30, 2018 All links from now served over https Jul 31, 2018 Use https with weblog URI May 2, 2018
Rakefile Use frozen string literal in root files Aug 13, 2017
package.json Make Webpacker the default JavaScript compiler for Rails 6 (#33079) Oct 1, 2018
rails.gemspec Rails 6 requires Ruby 2.4.1+ Feb 17, 2018
version.rb Start Rails 6.0 development!!! Jan 30, 2018

Welcome to Rails

What's Rails

Rails is a web-application framework that includes everything needed to create database-backed web applications according to the Model-View-Controller (MVC) pattern.

Understanding the MVC pattern is key to understanding Rails. MVC divides your application into three layers: Model, View, and Controller, each with a specific responsibility.

Model layer

The Model layer represents the domain model (such as Account, Product, Person, Post, etc.) and encapsulates the business logic specific to your application. In Rails, database-backed model classes are derived from ActiveRecord::Base. Active Record allows you to present the data from database rows as objects and embellish these data objects with business logic methods. Although most Rails models are backed by a database, models can also be ordinary Ruby classes, or Ruby classes that implement a set of interfaces as provided by the Active Model module.

Controller layer

The Controller layer is responsible for handling incoming HTTP requests and providing a suitable response. Usually this means returning HTML, but Rails controllers can also generate XML, JSON, PDFs, mobile-specific views, and more. Controllers load and manipulate models, and render view templates in order to generate the appropriate HTTP response. In Rails, incoming requests are routed by Action Dispatch to an appropriate controller, and controller classes are derived from ActionController::Base. Action Dispatch and Action Controller are bundled together in Action Pack.

View layer

The View layer is composed of "templates" that are responsible for providing appropriate representations of your application's resources. Templates can come in a variety of formats, but most view templates are HTML with embedded Ruby code (ERB files). Views are typically rendered to generate a controller response, or to generate the body of an email. In Rails, View generation is handled by Action View.

Frameworks and libraries

Active Record, Active Model, Action Pack, and Action View can each be used independently outside Rails. In addition to that, Rails also comes with Action Mailer, a library to generate and send emails; Active Job, a framework for declaring jobs and making them run on a variety of queueing backends; Action Cable, a framework to integrate WebSockets with a Rails application; Active Storage, a library to attach cloud and local files to Rails applications; and Active Support, a collection of utility classes and standard library extensions that are useful for Rails, and may also be used independently outside Rails.

Getting Started

  1. Install Rails at the command prompt if you haven't yet:

     $ gem install rails
  2. At the command prompt, create a new Rails application:

     $ rails new myapp

    where "myapp" is the application name.

  3. Change directory to myapp and start the web server:

     $ cd myapp
     $ rails server

    Run with --help or -h for options.

  4. Go to http://localhost:3000 and you'll see: "Yay! You’re on Rails!"

  5. Follow the guidelines to start developing your application. You may find the following resources handy:


Code Triage Badge

We encourage you to contribute to Ruby on Rails! Please check out the Contributing to Ruby on Rails guide for guidelines about how to proceed. Join us!

Trying to report a possible security vulnerability in Rails? Please check out our security policy for guidelines about how to proceed.

Everyone interacting in Rails and its sub-projects' codebases, issue trackers, chat rooms, and mailing lists is expected to follow the Rails code of conduct.

Code Status

Build Status


Ruby on Rails is released under the MIT License.