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Merge pull request #19592 from adimitri/activerecord-find-ambiguity

Combine complementary AR #find doc lines
latest commit a408957613
@rafaelfranca rafaelfranca authored
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actionmailer [skip ci] Fix typo in actionmailer documentation
actionpack Merge pull request #19544 from shuhei/fix-parameters-const-missing
actionview Merge pull request #19535 from JuanitoFatas/doc/av-comment
activejob Merge pull request #19034 from jvanbaarsen/explicit-job-base-class
activemodel Merge pull request #19021 from morgoth/activemodel-errors-refactoring
activerecord [ci skip] Combine complementary AR #find doc lines
activesupport Require the extensions to tests pass in isolation
ci Pass symbol as an argument instead of a block
guides Merge pull request #19034 from jvanbaarsen/explicit-job-base-class
railties Merge pull request #19034 from jvanbaarsen/explicit-job-base-class
tasks activejob needs to be built before actionmailer
tools Doc fix [ci skip]
.gitignore Track Gemfile.lock at the repository
.travis.yml Revert "Allow failures with Active Job"
.yardopts Let YARD document the railties gem Changed "in GitHub" to "on GitHub" [ci skip]
Gemfile Test using sprockets 3
Gemfile.lock Test using sprockets 3
RAILS_VERSION Start Rails 5 development :tada: Remove bullet
RELEASING_RAILS.rdoc Remove note about supported plugins from the releasing docs
Rakefile Remove activejob integration tests
install.rb Added activejob to install.rb
load_paths.rb require "rubygems" is obsolete in Ruby 1.9.3
rails.gemspec Target Ruby 2.2.1 in gemspecs
version.rb Start Rails 5 development :tada:

Welcome to 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, each with a specific responsibility.

The Model layer represents your domain model (such as Account, Product, Person, Post, etc.) and encapsulates the business logic that is 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. You can read more about Active Record in its README. 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. You can read more about Active Model in its README.

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. You can read more about Action Pack in its README.

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. You can read more about Action View in its README.

Active Record, Action Pack, and Action View can each be used independently outside Rails. In addition to them, Rails also comes with Action Mailer (README), a library to generate and send emails; Active Job (README), a framework for declaring jobs and making them run on a variety of queueing backends; and Active Support (README), 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. Using a browser, go to http://localhost:3000 and you'll see: "Welcome aboard: You're riding Ruby on Rails!"

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


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!

Code Status

Build Status


Ruby on Rails is released under the MIT License.

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