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Diffstat (limited to 'guides/source/getting_started.md')
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1 files changed, 39 insertions, 38 deletions
diff --git a/guides/source/getting_started.md b/guides/source/getting_started.md index 5ef376531d..9f38de6247 100644 --- a/guides/source/getting_started.md +++ b/guides/source/getting_started.md @@ -24,8 +24,11 @@ with Rails. However, to get the most out of it, you need to have some prerequisites installed: * The [Ruby](https://www.ruby-lang.org/en/downloads) language version 2.2.2 or newer. -* The [RubyGems](https://rubygems.org) packaging system, which is installed with Ruby - versions 1.9 and later. To learn more about RubyGems, please read the [RubyGems Guides](http://guides.rubygems.org). +* Right version of [Development Kit](http://rubyinstaller.org/downloads/), if you + are using Windows. +* The [RubyGems](https://rubygems.org) packaging system, which is installed with + Ruby by default. To learn more about RubyGems, please read the + [RubyGems Guides](http://guides.rubygems.org). * A working installation of the [SQLite3 Database](https://www.sqlite.org). Rails is a web application framework running on the Ruby programming language. @@ -34,7 +37,7 @@ curve diving straight into Rails. There are several curated lists of online reso for learning Ruby: * [Official Ruby Programming Language website](https://www.ruby-lang.org/en/documentation/) -* [reSRC's List of Free Programming Books](http://resrc.io/list/10/list-of-free-programming-books/#ruby) +* [List of Free Programming Books](https://github.com/vhf/free-programming-books/blob/master/free-programming-books.md#ruby) Be aware that some resources, while still excellent, cover versions of Ruby as old as 1.6, and commonly 1.8, and will not include some syntax that you will see in day-to-day @@ -69,10 +72,9 @@ The Rails philosophy includes two major guiding principles: Creating a New Rails Project ---------------------------- - -The best way to use this guide is to follow each step as it happens, no code or -step needed to make this example application has been left out, so you can -literally follow along step by step. +The best way to read this guide is to follow it step by step. All steps are +essential to run this example application and no additional code or steps are +needed. By following along with this guide, you'll create a Rails project called `blog`, a (very) simple weblog. Before you can start building the application, @@ -89,17 +91,17 @@ Open up a command line prompt. On Mac OS X open Terminal.app, on Windows choose dollar sign `$` should be run in the command line. Verify that you have a current version of Ruby installed: +```bash +$ ruby -v +ruby 2.2.2p95 +``` + TIP: A number of tools exist to help you quickly install Ruby and Ruby on Rails on your system. Windows users can use [Rails Installer](http://railsinstaller.org), while Mac OS X users can use [Tokaido](https://github.com/tokaido/tokaidoapp). For more installation methods for most Operating Systems take a look at [ruby-lang.org](https://www.ruby-lang.org/en/documentation/installation/). -```bash -$ ruby -v -ruby 2.2.2p95 -``` - Many popular UNIX-like OSes ship with an acceptable version of SQLite3. On Windows, if you installed Rails through Rails Installer, you already have SQLite installed. Others can find installation instructions @@ -163,7 +165,7 @@ of the files and folders that Rails created by default: | File/Folder | Purpose | | ----------- | ------- | |app/|Contains the controllers, models, views, helpers, mailers and assets for your application. You'll focus on this folder for the remainder of this guide.| -|bin/|Contains the rails script that starts your app and can contain other scripts you use to setup, deploy or run your application.| +|bin/|Contains the rails script that starts your app and can contain other scripts you use to setup, update, deploy or run your application.| |config/|Configure your application's routes, database, and more. This is covered in more detail in [Configuring Rails Applications](configuring.html).| |config.ru|Rack configuration for Rack based servers used to start the application.| |db/|Contains your current database schema, as well as the database migrations.| @@ -172,7 +174,7 @@ of the files and folders that Rails created by default: |log/|Application log files.| |public/|The only folder seen by the world as-is. Contains static files and compiled assets.| |Rakefile|This file locates and loads tasks that can be run from the command line. The task definitions are defined throughout the components of Rails. Rather than changing Rakefile, you should add your own tasks by adding files to the lib/tasks directory of your application.| -|README.rdoc|This is a brief instruction manual for your application. You should edit this file to tell others what your application does, how to set it up, and so on.| +|README.md|This is a brief instruction manual for your application. You should edit this file to tell others what your application does, how to set it up, and so on.| |test/|Unit tests, fixtures, and other test apparatus. These are covered in [Testing Rails Applications](testing.html).| |tmp/|Temporary files (like cache and pid files).| |vendor/|A place for all third-party code. In a typical Rails application this includes vendored gems.| @@ -298,6 +300,7 @@ Rails.application.routes.draw do # The priority is based upon order of creation: # first created -> highest priority. + # See how all your routes lay out with "rake routes". # # You can have the root of your site routed with "root" # root 'welcome#index' @@ -400,7 +403,7 @@ a controller called `ArticlesController`. You can do this by running this command: ```bash -$ bin/rails g controller articles +$ bin/rails generate controller articles ``` If you open up the newly generated `app/controllers/articles_controller.rb` @@ -619,7 +622,7 @@ def create end ``` -The `render` method here is taking a very simple hash with a key of `plain` and +The `render` method here is taking a very simple hash with a key of `:plain` and value of `params[:article].inspect`. The `params` method is the object which represents the parameters (or fields) coming in from the form. The `params` method returns an `ActiveSupport::HashWithIndifferentAccess` object, which @@ -677,7 +680,7 @@ If you look in the `db/migrate/YYYYMMDDHHMMSS_create_articles.rb` file (remember, yours will have a slightly different name), here's what you'll find: ```ruby -class CreateArticles < ActiveRecord::Migration +class CreateArticles < ActiveRecord::Migration[5.0] def change create_table :articles do |t| t.string :title @@ -988,21 +991,22 @@ and restart the web server when a change is made. The model file, `app/models/article.rb` is about as simple as it can get: ```ruby -class Article < ActiveRecord::Base +class Article < ApplicationRecord end ``` There isn't much to this file - but note that the `Article` class inherits from -`ActiveRecord::Base`. Active Record supplies a great deal of functionality to -your Rails models for free, including basic database CRUD (Create, Read, Update, -Destroy) operations, data validation, as well as sophisticated search support -and the ability to relate multiple models to one another. +`ApplicationRecord`. `ApplicationRecord` inherits from `ActiveRecord::Base` +which supplies a great deal of functionality to your Rails models for free, +including basic database CRUD (Create, Read, Update, Destroy) operations, data +validation, as well as sophisticated search support and the ability to relate +multiple models to one another. Rails includes methods to help you validate the data that you send to models. Open the `app/models/article.rb` file and edit it: ```ruby -class Article < ActiveRecord::Base +class Article < ApplicationRecord validates :title, presence: true, length: { minimum: 5 } end @@ -1240,7 +1244,9 @@ article we want to show the form back to the user. We reuse the `article_params` method that we defined earlier for the create action. -TIP: It is not necessary to pass all the attributes to `update`. For example, if `@article.update(title: 'A new title')` were called, Rails would only update the `title` attribute, leaving all other attributes untouched. +TIP: It is not necessary to pass all the attributes to `update`. For example, +if `@article.update(title: 'A new title')` was called, Rails would only update +the `title` attribute, leaving all other attributes untouched. Finally, we want to show a link to the `edit` action in the list of all the articles, so let's add that now to `app/views/articles/index.html.erb` to make @@ -1525,7 +1531,7 @@ This command will generate four files: First, take a look at `app/models/comment.rb`: ```ruby -class Comment < ActiveRecord::Base +class Comment < ApplicationRecord belongs_to :article end ``` @@ -1538,25 +1544,22 @@ In addition to the model, Rails has also made a migration to create the corresponding database table: ```ruby -class CreateComments < ActiveRecord::Migration +class CreateComments < ActiveRecord::Migration[5.0] def change create_table :comments do |t| t.string :commenter t.text :body - - # this line adds an integer column called `article_id`. - t.references :article, index: true + t.references :article, index: true, foreign_key: true t.timestamps null: false end - add_foreign_key :comments, :articles end end ``` -The `t.references` line sets up a foreign key column for the association between -the two models. An index for this association is also created on this column. -Go ahead and run the migration: +The `t.references` line creates an integer column called `article_id`, an index +for it, and a foreign key constraint that points to the `id` column of the `articles` +table. Go ahead and run the migration: ```bash $ bin/rake db:migrate @@ -1569,8 +1572,6 @@ run against the current database, so in this case you will just see: == CreateComments: migrating ================================================= -- create_table(:comments) -> 0.0115s --- add_foreign_key(:comments, :articles) - -> 0.0000s == CreateComments: migrated (0.0119s) ======================================== ``` @@ -1588,7 +1589,7 @@ association. You've already seen the line of code inside the `Comment` model (app/models/comment.rb) that makes each comment belong to an Article: ```ruby -class Comment < ActiveRecord::Base +class Comment < ApplicationRecord belongs_to :article end ``` @@ -1597,7 +1598,7 @@ You'll need to edit `app/models/article.rb` to add the other side of the association: ```ruby -class Article < ActiveRecord::Base +class Article < ApplicationRecord has_many :comments validates :title, presence: true, length: { minimum: 5 } @@ -1963,7 +1964,7 @@ you to use the `dependent` option of an association to achieve this. Modify the Article model, `app/models/article.rb`, as follows: ```ruby -class Article < ActiveRecord::Base +class Article < ApplicationRecord has_many :comments, dependent: :destroy validates :title, presence: true, length: { minimum: 5 } |