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Diffstat (limited to 'railties/guides/source/getting_started.textile')
| -rw-r--r-- | railties/guides/source/getting_started.textile | 45 |
1 files changed, 19 insertions, 26 deletions
diff --git a/railties/guides/source/getting_started.textile b/railties/guides/source/getting_started.textile index 3f9bd2b6da..a826a33120 100644 --- a/railties/guides/source/getting_started.textile +++ b/railties/guides/source/getting_started.textile @@ -22,7 +22,7 @@ TIP: Note that Ruby 1.8.7 p248 and p249 have marshaling bugs that crash Rails 3. * The "RubyGems":http://rubyforge.org/frs/?group_id=126 packaging system * A working installation of the "SQLite3 Database":http://www.sqlite.org -Rails is a web application framework running on the Ruby programming language. If you have no prior experience with Ruby, you will find a very steep learning curve diving straight into Rails. There are some good free resources on the internet for learning Ruby, including: +Rails is a web application framework running on the Ruby programming language. If you have no prior experience with Ruby, you will find a very steep learning curve diving straight into Rails. There are some good free resources on the internet for learning Ruby, including: * "Mr. Neighborly's Humble Little Ruby Book":http://www.humblelittlerubybook.com * "Programming Ruby":http://www.ruby-doc.org/docs/ProgrammingRuby/ @@ -78,7 +78,7 @@ Rails ships as many individual components. h5. Action Pack -Action Pack is a single gem that contains Action Controller, Action View and Action Dispatch. The "VC" part of "MVC". +Action Pack is a single gem that contains Action Controller, Action View and Action Dispatch. The "VC" part of "MVC". h5. Action Controller @@ -98,7 +98,7 @@ Action Mailer is a framework for building e-mail services. You can use Action Ma h5. Active Model -Active Model provides a defined interface between the Action Pack gem services and Object Relationship Mapping gems such as Active Record. Active Model allows Rails to utilize other ORM frameworks in place of Active Record if your application needs this. +Active Model provides a defined interface between the Action Pack gem services and Object Relationship Mapping gems such as Active Record. Active Model allows Rails to utilize other ORM frameworks in place of Active Record if your application needs this. h5. Active Record @@ -153,7 +153,7 @@ TIP. If you're working on Windows, you can quickly install Ruby and Rails with " h4. Creating the Blog Application -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. If you need to see the completed code, you can download it from "Getting Started Code":https://github.com/mikel/getting-started-code. +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. If you need to see the completed code, you can download it from "Getting Started Code":https://github.com/mikel/getting-started-code. To begin, open a terminal, navigate to a folder where you have rights to create files, and type: @@ -184,7 +184,7 @@ In any case, Rails will create a folder in your working directory called <tt>blo |doc/|In-depth documentation for your application.| |lib/|Extended modules for your application (not covered in this guide).| |log/|Application log files.| -|public/|The only folder seen to the world as-is. This is where your images, JavaScript files, stylesheets (CSS), and other static files go.| +|public/|The only folder seen to the world as-is. This is where your images, JavaScript files, stylesheets (CSS), and other static files go.| |script/|Contains the rails script that starts your app and can contain other scripts you use to deploy or run your application.| |test/|Unit tests, fixtures, and other test apparatus. These are covered in "Testing Rails Applications":testing.html| |tmp/|Temporary files| @@ -290,7 +290,7 @@ This will fire up an instance of the WEBrick web server by default (Rails can al TIP: To stop the web server, hit Ctrl+C in the terminal window where it's running. In development mode, Rails does not generally require you to stop the server; changes you make in files will be automatically picked up by the server. -The "Welcome Aboard" page is the _smoke test_ for a new Rails application: it makes sure that you have your software configured correctly enough to serve a page. You can also click on the _About your application’s environment_ link to see a summary of your Application's environment. +The "Welcome Aboard" page is the _smoke test_ for a new Rails application: it makes sure that you have your software configured correctly enough to serve a page. You can also click on the _About your application’s environment_ link to see a summary of your Application's environment. h4. Say "Hello", Rails @@ -310,7 +310,7 @@ Rails will create several files for you, including +app/views/home/index.html.er h4. Setting the Application Home Page -Now that we have made the controller and view, we need to tell Rails when we want "Hello Rails" to show up. In our case, we want it to show up when we navigate to the root URL of our site, "http://localhost:3000":http://localhost:3000, instead of the "Welcome Aboard" smoke test. +Now that we have made the controller and view, we need to tell Rails when we want "Hello Rails" to show up. In our case, we want it to show up when we navigate to the root URL of our site, "http://localhost:3000":http://localhost:3000, instead of the "Welcome Aboard" smoke test. The first step to doing this is to delete the default page from your application: @@ -378,7 +378,7 @@ If you look in the +db/migrate/20100207214725_create_posts.rb+ file (remember, y <ruby> class CreatePosts < ActiveRecord::Migration - def self.up + def change create_table :posts do |t| t.string :name t.string :title @@ -387,14 +387,10 @@ class CreatePosts < ActiveRecord::Migration t.timestamps end end - - def self.down - drop_table :posts - end end </ruby> -The above migration creates two methods, +up+, called when you run this migration into the database, and +down+ in case you need to reverse the changes made by this migration at a later date. The +up+ command in this case creates a +posts+ table with two string columns and a text column. It also creates two timestamp fields to track record creation and updating. More information about Rails migrations can be found in the "Rails Database Migrations":migrations.html guide. +The above migration creates a method name +change+ which will be called when you run this migration. The action defined in that method is also reversible, which means Rails knows how to reverse the change made by this migration, in case you want to reverse it at later date. By default, when you run this migration it will creates a +posts+ table with two string columns and a text column. It also creates two timestamp fields to track record creation and updating. More information about Rails migrations can be found in the "Rails Database Migrations":migrations.html guide. At this point, you can use a rake command to run the migration: @@ -548,7 +544,7 @@ This view iterates over the contents of the +@posts+ array to display content an * +link_to+ builds a hyperlink to a particular destination * +edit_post_path+ and +new_post_path+ are helpers that Rails provides as part of RESTful routing. You'll see a variety of these helpers for the different actions that the controller includes. -NOTE. In previous versions of Rails, you had to use +<%=h post.name %>+ so that any HTML would be escaped before being inserted into the page. In Rails 3.0, this is now the default. To get unescaped HTML, you now use +<%= raw post.name %>+. +NOTE. In previous versions of Rails, you had to use +<%=h post.name %>+ so that any HTML would be escaped before being inserted into the page. In Rails 3.0, this is now the default. To get unescaped HTML, you now use +<%= raw post.name %>+. TIP: For more details on the rendering process, see "Layouts and Rendering in Rails":layouts_and_rendering.html. @@ -600,7 +596,7 @@ The +new.html.erb+ view displays this empty Post to the user: <%= link_to 'Back', posts_path %> </erb> -The +<%= render 'form' %>+ line is our first introduction to _partials_ in Rails. A partial is a snippet of HTML and Ruby code that can be reused in multiple locations. In this case, the form used to make a new post, is basically identical to a form used to edit a post, both have text fields for the name and title and a text area for the content with a button to make a new post or update the existing post. +The +<%= render 'form' %>+ line is our first introduction to _partials_ in Rails. A partial is a snippet of HTML and Ruby code that can be reused in multiple locations. In this case, the form used to make a new post, is basically identical to a form used to edit a post, both have text fields for the name and title and a text area for the content with a button to make a new post or update the existing post. If you take a look at +views/posts/_form.html.erb+ file, you will see the following: @@ -807,7 +803,7 @@ In addition to the model, Rails has also made a migration to create the correspo <ruby> class CreateComments < ActiveRecord::Migration - def self.up + def change create_table :comments do |t| t.string :commenter t.text :body @@ -818,10 +814,6 @@ class CreateComments < ActiveRecord::Migration add_index :comments, :post_id end - - def self.down - drop_table :comments - end end </ruby> @@ -873,7 +865,7 @@ TIP: For more information on Active Record associations, see the "Active Record h4. Adding a Route for Comments -As with the +home+ controller, we will need to add a route so that Rails knows where we would like to navigate to see +comments+. Open up the +config/routes.rb+ file again, you will see an entry that was added automatically for +posts+ near the top by the scaffold generator, +resources :posts+, edit it as follows: +As with the +home+ controller, we will need to add a route so that Rails knows where we would like to navigate to see +comments+. Open up the +config/routes.rb+ file again, you will see an entry that was added automatically for +posts+ near the top by the scaffold generator, +resources :posts+, edit it as follows: <ruby> resources :posts do @@ -901,7 +893,7 @@ This creates four files and one empty directory: * +test/unit/helpers/comments_helper_test.rb+ - The unit tests for the helper * +app/views/comments/+ - Views of the controller are stored here -Like with any blog, our readers will create their comments directly after reading the post, and once they have added their comment, will be sent back to the post show page to see their comment now listed. Due to this, our +CommentsController+ is there to provide a method to create comments and delete SPAM comments when they arrive. +Like with any blog, our readers will create their comments directly after reading the post, and once they have added their comment, will be sent back to the post show page to see their comment now listed. Due to this, our +CommentsController+ is there to provide a method to create comments and delete SPAM comments when they arrive. So first, we'll wire up the Post show template (+/app/views/posts/show.html.erb+) to let us make a new comment: @@ -1078,7 +1070,7 @@ Then in the +app/views/posts/show.html.erb+ you can change it to look like the f <%= link_to 'Back to Posts', posts_path %> | </erb> -This will now render the partial in +app/views/comments/_comment.html.erb+ once for each comment that is in the +@post.comments+ collection. As the +render+ method iterates over the <tt>@post.comments</tt> collection, it assigns each comment to a local variable named the same as the partial, in this case +comment+ which is then available in the partial for us to show. +This will now render the partial in +app/views/comments/_comment.html.erb+ once for each comment that is in the +@post.comments+ collection. As the +render+ method iterates over the <tt>@post.comments</tt> collection, it assigns each comment to a local variable named the same as the partial, in this case +comment+ which is then available in the partial for us to show. h4. Rendering a Partial Form @@ -1138,7 +1130,7 @@ The +@post+ object is available to any partials rendered in the view because we h3. Deleting Comments -Another important feature on a blog is being able to delete SPAM comments. To do this, we need to implement a link of some sort in the view and a +DELETE+ action in the +CommentsController+. +Another important feature on a blog is being able to delete SPAM comments. To do this, we need to implement a link of some sort in the view and a +DELETE+ action in the +CommentsController+. So first, let's add the delete link in the +app/views/comments/_comment.html.erb+ partial: @@ -1312,7 +1304,7 @@ Note that we have changed the +f+ in +form_for(@post) do |f|+ to +post_form+ to This example shows another option of the render helper, being able to pass in local variables, in this case, we want the local variable +form+ in the partial to refer to the +post_form+ object. -We also add a <tt>@post.tags.build</tt> at the top of this form, this is to make sure there is a new tag ready to have it's name filled in by the user. If you do not build the new tag, then the form will not appear as there is no new Tag object ready to create. +We also add a <tt>@post.tags.build</tt> at the top of this form, this is to make sure there is a new tag ready to have it's name filled in by the user. If you do not build the new tag, then the form will not appear as there is no new Tag object ready to create. Now create the folder <tt>app/views/tags</tt> and make a file in there called <tt>_form.html.erb</tt> which contains the form for the tag: @@ -1373,7 +1365,7 @@ However, that method call <tt>@post.tags.map { |t| t.name }.join(", ")</tt> is a h3. View Helpers -View Helpers live in <tt>app/helpers</tt> and provide small snippets of reusable code for views. In our case, we want a method that strings a bunch of objects together using their name attribute and joining them with a comma. As this is for the Post show template, we put it in the PostsHelper. +View Helpers live in <tt>app/helpers</tt> and provide small snippets of reusable code for views. In our case, we want a method that strings a bunch of objects together using their name attribute and joining them with a comma. As this is for the Post show template, we put it in the PostsHelper. Open up <tt>app/helpers/posts_helper.rb</tt> and add the following: @@ -1458,6 +1450,7 @@ Two very common sources of data that are not UTF-8: h3. Changelog +* April 26, 2011: Changed migration code from +up+, +down+ pair to +change+ method "Prem Sichanugrist":"http://sikachu.com" * April 11, 2011: Changed scaffold_controller generator to create format block for JSON instead of XML "Sebastian Martinez":http://www.wyeworks.com * August 30, 2010: Minor editing after Rails 3 release by "Joost Baaij":http://www.spacebabies.nl * July 12, 2010: Fixes, editing and updating of code samples by "Jaime Iniesta":http://jaimeiniesta.com |