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1 files changed, 169 insertions, 122 deletions
diff --git a/guides/source/getting_started.textile b/guides/source/getting_started.textile
index 1e9bd1f144..19bd106ff0 100644
--- a/guides/source/getting_started.textile
+++ b/guides/source/getting_started.textile
@@ -183,9 +183,9 @@ Rails will create several files for you. Most important of these are of course t
Open the +app/views/welcome/index.html.erb+ file in your text editor and edit it to contain a single line of code:
-<code class="html">
+<html>
<h1>Hello, Rails!</h1>
-</code>
+</html>
h4. Setting the Application Home Page
@@ -193,7 +193,7 @@ Now that we have made the controller and view, we need to tell Rails when we wan
To fix this, delete the +index.html+ file located inside the +public+ directory of the application.
-You need to do this because Rails will serve any static file in the +public+ directory that matches a route in preference to any dynamic content you generate from the controllers.
+You need to do this because Rails will serve any static file in the +public+ directory that matches a route in preference to any dynamic content you generate from the controllers. The +index.html+ file is special: it will be served if a request comes in at the root route, e.g. http://localhost:3000. If another request such as http://localhost:3000/welcome happened, a static file at <tt>public/welcome.html</tt> would be served first, but only if it existed.
Next, you have to tell Rails where your actual home page is located.
@@ -210,7 +210,7 @@ Blog::Application.routes.draw do
The +root :to => "welcome#index"+ tells Rails to map requests to the root of the application to the welcome controller's index action. This was created earlier when you ran the controller generator (+rails generate controller welcome index+).
-If you navigate to "http://localhost:3000":http://localhost:3000 in your browser, you'll see +Hello, Rails!+.
+If you navigate to "http://localhost:3000":http://localhost:3000 in your browser, you'll see the +Hello, Rails!+ message you put into +app/views/welcome/index.html.erb+, indicating that this new route is indeed going to +WelcomeController+'s +index+ action and is rendering the view correctly.
NOTE. For more information about routing, refer to "Rails Routing from the Outside In":routing.html.
@@ -220,7 +220,7 @@ Now that you've seen how to create a controller, an action and a view, let's cre
In the Blog application, you will now create a new _resource_. A resource is the term used for a collection of similar objects, such as posts, people or animals. You can create, read, update and destroy items for a resource and these operations are referred to as _CRUD_ operations.
-In the next section, you will add the ability to create new posts in your application and be able to view them. This is the "CR" from CRUD. The form for doing this will look like this:
+In the next section, you will add the ability to create new posts in your application and be able to view them. This is the "C" and the "R" from CRUD: creation and reading. The form for doing this will look like this:
!images/getting_started/new_post.png(The new post form)!
@@ -232,7 +232,7 @@ The first thing that you are going to need to create a new post within the appli
!images/getting_started/routing_error_no_route_matches.png(A routing error, no route matches /posts/new)!
-This is because there is nowhere inside the routes for the application -- defined inside +config/routes.rb+ -- that defines this route. By default, Rails has no routes configured at all, and so you must define your routes as you need them.
+This is because there is nowhere inside the routes for the application -- defined inside +config/routes.rb+ -- that defines this route. By default, Rails has no routes configured at all, besides the root route you defined earlier, and so you must define your routes as you need them.
To do this, you're going to need to create a route inside +config/routes.rb+ file, on a new line between the +do+ and the +end+ for the +draw+ method:
@@ -282,9 +282,9 @@ You're getting this error now because Rails expects plain actions like this one
In the above image, the bottom line has been truncated. Let's see what the full thing looks like:
-<text>
+<blockquote>
Missing template posts/new, application/new with {:locale=>[:en], :formats=>[:html], :handlers=>[:erb, :builder, :coffee]}. Searched in: * "/path/to/blog/app/views"
-</text>
+</blockquote>
That's quite a lot of text! Let's quickly go through and understand what each part of it does.
@@ -330,11 +330,17 @@ method called +form_for+. To use this method, add this code into +app/views/post
If you refresh the page now, you'll see the exact same form as in the example. Building forms in Rails is really just that easy!
-When you call +form_for+, you pass it an identifying object for this form. In this case, it's the symbol +:post+. This tells the +form_for+ helper what this form is for. Inside the block for this method, the FormBuilder object -- represented by +f+ -- is used to build two labels and two text fields, one each for the title and text of a post. Finally, a call to +submit+ on the +f+ object will create a submit button for the form.
+When you call +form_for+, you pass it an identifying object for this
+form. In this case, it's the symbol +:post+. This tells the +form_for+
+helper what this form is for. Inside the block for this method, the
++FormBuilder+ object -- represented by +f+ -- is used to build two labels and two text fields, one each for the title and text of a post. Finally, a call to +submit+ on the +f+ object will create a submit button for the form.
There's one problem with this form though. If you inspect the HTML that is generated, by viewing the source of the page, you will see that the +action+ attribute for the form is pointing at +/posts/new+. This is a problem because this route goes to the very page that you're on right at the moment, and that route should only be used to display the form for a new post.
-So the form needs to use a different URL in order to go somewhere else. This can be done quite simply with the +:url+ option of +form_for+. Typically in Rails, the action that is used for new form submissions like this is called "create", and so the form should be pointed to this action.
+The form needs to use a different URL in order to go somewhere else.
+This can be done quite simply with the +:url+ option of +form_for+.
+Typically in Rails, the action that is used for new form submissions
+like this is called "create", and so the form should be pointed to that action.
Edit the +form_for+ line inside +app/views/posts/new.html.erb+ to look like this:
@@ -350,11 +356,11 @@ post "posts/create"
By using the +post+ method rather than the +get+ method, Rails will define a route that will only respond to POST methods. The POST method is the typical method used by forms all over the web.
-With the form and the route for it defined now, you will be able to fill in the form and then click the submit button to begin the process of creating a new post, so go ahead and do that. When you submit the form, you should see a familiar error:
+With the form and its associated route defined, you will be able to fill in the form and then click the submit button to begin the process of creating a new post, so go ahead and do that. When you submit the form, you should see a familiar error:
!images/getting_started/unknown_action_create_for_posts.png(Unknown action create for PostsController)!
-You will now need to create the +create+ action within the +PostsController+ for this to work.
+You now need to create the +create+ action within the +PostsController+ for this to work.
h4. Creating posts
@@ -381,7 +387,7 @@ def create
end
</ruby>
-The +render+ method here is taking a very simple hash with the key of +text+ and the value of +params[:post].inspect+. The +params+ method here is the object which represents the parameters (or fields) coming in from the form. The +params+ method returns a +HashWithIndifferentAccess+ object, which allows you to access the keys of the hash using either strings or symbols. In this situation, the only parameters that matter are the ones from the form.
+The +render+ method here is taking a very simple hash with a key of +text+ and value of +params[:post].inspect+. The +params+ method is the object which represents the parameters (or fields) coming in from the form. The +params+ method returns a +HashWithIndifferentAccess+ object, which allows you to access the keys of the hash using either strings or symbols. In this situation, the only parameters that matter are the ones from the form.
If you re-submit the form one more time you'll now no longer get the missing template error. Instead, you'll see something that looks like the following:
@@ -402,16 +408,22 @@ To create the new model, run this command in your terminal:
$ rails generate model Post title:string text:text
</shell>
-With that command we told Rails that we want a +Post+ model, which in
-turn should have a title attribute of type string, and a text attribute
+With that command we told Rails that we want a +Post+ model, together
+with a _title_ attribute of type string, and a _text_ attribute
of type text. Those attributes are automatically added to the +posts+
table in the database and mapped to the +Post+ model.
-Rails in turn responded by creating a bunch of files. For
+Rails responded by creating a bunch of files. For
now, we're only interested in +app/models/post.rb+ and
-+db/migrate/20120419084633_create_posts.rb+. The latter is responsible
++db/migrate/20120419084633_create_posts.rb+ (your name could be a bit
+different). The latter is responsible
for creating the database structure, which is what we'll look at next.
+TIP: Active Record is smart enough to automatically map column names to
+model attributes, which means you don't have to declare attributes
+inside Rails models, as that will be done automatically by Active
+Record.
+
h4. Running a Migration
As we've just seen, +rails generate model+ created a _database
@@ -472,8 +484,8 @@ invoking the command: +rake db:migrate RAILS_ENV=production+.
h4. Saving data in the controller
Back in +posts_controller+, we need to change the +create+ action
-to use the new +Post+ model to save data in the database. Open that file
-and change the +create+ action to look like the following:
+to use the new +Post+ model to save the data in the database. Open that file
+and change the +create+ action to look like this:
<ruby>
def create
@@ -485,22 +497,21 @@ end
</ruby>
Here's what's going on: every Rails model can be initialized with its
-respective attributes, which are automatically mapped to its
+respective attributes, which are automatically mapped to the respective
database columns. In the first line we do just that (remember that
+params[:post]+ contains the attributes we're interested in). Then,
+@post.save+ is responsible for saving the model in the database.
-Finally, on the last line we redirect the user to the +show+ action,
-wich we have not defined yet.
+Finally, we redirect the user to the +show+ action,
+wich we'll define later.
TIP: As we'll see later, +@post.save+ returns a boolean indicating
-wherever the model was saved or not, and you can (and usually do) take
-different actions depending on the result of calling +@post.save+.
+wherever the model was saved or not.
-h4. Showing posts
+h4. Showing Posts
-Before trying to create a new post, let's add the +show+ action, which
-will be responsible for showing our posts. Open +config/routes.rb+
-and add the following route:
+If you submit the form again now, Rails will complain about not finding
+the +show+ action. That's not very useful though, so let's add the
++show+ action before proceeding. Open +config/routes.rb+ and add the following route:
<ruby>
get "posts/:id" => "posts#show"
@@ -549,19 +560,21 @@ be able to create a post. Try it!
h4. Listing all posts
We still need a way to list all our posts, so let's do that. As usual,
-we'll need a route, a controller action, and a view:
+we'll need a route placed into +config/routes.rb+:
<ruby>
-# Add to config/routes.rb
get "posts" => "posts#index"
+</ruby>
+
+And an action for that route inside the +PostsController+ in the +app/controllers/posts_controller.rb+ file:
-# Add to app/controllers/posts_controller.rb
+<ruby>
def index
@posts = Post.all
end
</ruby>
-+app/view/posts/index.html.erb+:
+And then finally a view for this action, located at +app/views/posts/index.html.erb+:
<erb>
<h1>Listing posts</h1>
@@ -572,15 +585,17 @@ end
<th>Text</th>
</tr>
-<% @posts.each do |post| %>
- <tr>
- <td><%= post.title %></td>
- <td><%= post.text %></td>
- </tr>
-<% end %>
+ <% @posts.each do |post| %>
+ <tr>
+ <td><%= post.title %></td>
+ <td><%= post.text %></td>
+ </tr>
+ <% end %>
</table>
</erb>
+Now if you go to +http://localhost:3000/posts+ you will see a list of all the posts that you have created.
+
h4. Adding links
You can now create, show, and list posts. Now let's add some links to
@@ -597,41 +612,25 @@ The +link_to+ method is one of Rails' built-in view helpers. It creates a
hyperlink based on text to display and where to go - in this case, to the path
for posts.
-Let's add links to the other views as well.
+Let's add links to the other views as well, starting with adding this "New Post" link to +app/views/posts/index.html.erb+, placing it above the +<table>+ tag:
<erb>
-# app/views/posts/index.html.erb
-
-<h1>Listing posts</h1>
-
<%= link_to 'New post', :action => :new %>
+</erb>
-<table>
- <tr>
- <th>Title</th>
- <th>Text</th>
- <th></th>
- </tr>
-
-<% @posts.each do |post| %>
- <tr>
- <td><%= post.title %></td>
- <td><%= post.text %></td>
- <td><%= link_to 'Show', :action => :show, :id => post.id %></td>
- </tr>
-<% end %>
-</table>
-
-# app/views/posts/new.html.erb
+This link will allow you to bring up the form that lets you create a new post. You should also add a link to this template -- +app/views/posts/new.html.erb+ -- to go back to the +index+ action. Do this by adding this underneath the form in this template:
+<erb>
<%= form_for :post do |f| %>
...
<% end %>
<%= link_to 'Back', :action => :index %>
+</erb>
-# app/views/posts/show.html.erb
+Finally, add another link to the +app/views/posts/show.html.erb+ template to go back to the +index+ action as well, so that people who are viewing a single post can go back and view the whole list again:
+<erb>
<p>
<strong>Title:</strong>
<%= @post.title %>
@@ -653,7 +652,7 @@ TIP: In development mode (which is what you're working in by default), Rails
reloads your application with every browser request, so there's no need to stop
and restart the web server when a change is made.
-h4. Adding Some Validation
+h4. Allowing the update of fields
The model file, +app/models/post.rb+ is about as simple as it can get:
@@ -668,11 +667,28 @@ 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 secure some of your model fields.
+Open the +app/models/post.rb+ file and edit it:
+
+<ruby>
+class Post < ActiveRecord::Base
+ attr_accessible :text, :title
+end
+</ruby>
+
+This change will ensure that all changes made through HTML forms can edit the content of the text and title fields.
+It will not be possible to define any other field value through forms. You can still define them by calling the `field=` method of course.
+Accessible attributes and the mass assignment probem is covered in details in the "Security guide":security.html#mass-assignment
+
+h4. Adding Some Validation
+
Rails includes methods to help you validate the data that you send to models.
Open the +app/models/post.rb+ file and edit it:
<ruby>
class Post < ActiveRecord::Base
+ attr_accessible :text, :title
+
validates :title, :presence => true,
:length => { :minimum => 5 }
end
@@ -684,9 +700,12 @@ format, and the existence of associated objects. Validations are covered in deta
in "Active Record Validations and
Callbacks":active_record_validations_callbacks.html#validations-overview
-If you open +posts_controller+ again, you'll notice that we don't check
-the result of calling +@post.save+. We need to change its behavior to
-show the form back to the user if any error occur:
+With the validation now in place, when you call +@post.save+ on an invalid
+post, it will return +false+. If you open +app/controllers/posts_controller.rb+
+again, you'll notice that we don't check the result of calling +@post.save+
+inside the +create+ action. If +@post.save+ fails in this situation, we need to
+show the form back to the user. To do this, change the +new+ and +create+
+actions inside +app/controllers/posts_controller.rb+ to these:
<ruby>
def new
@@ -704,13 +723,11 @@ def create
end
</ruby>
-Notice that I've also added +@post = Post.new+ to the +new+ action. I'll
-explain why I did that in the next section, for now add that to your
-controller as well.
+The +new+ action is now creating a new instance variable called +@post+, and
+you'll see why that is in just a few moments.
-Also notice that we use +render+ instead of +redirect_to+ when +save+
-returns false. We can use +render+ so that the +@post+ object is passed
-back to the view.
+Notice that inside the +create+ action we use +render+ instead of +redirect_to+ when +save+
+returns +false+. The +render+ method is used so that the +@post+ object is passed back to the +new+ template when it is rendered. This rendering is done within the same request as the form submission, whereas the +redirect_to+ will tell the browser to issue another request.
If you reload
"http://localhost:3000/posts/new":http://localhost:3000/posts/new and
@@ -754,9 +771,8 @@ A few things are going on. We check if there are any errors with
+@post.errors.any?+, and in that case we show a list of all
errors with +@post.errors.full_messages+.
-+pluralize+ is a rails helper
-that takes a number and a string as its arguments. If the number is
-greater than one, the string will be automatically pluralized.
++pluralize+ is a rails helper that takes a number and a string as its
+arguments. If the number is greater than one, the string will be automatically pluralized.
The reason why we added +@post = Post.new+ in +posts_controller+ is that
otherwise +@post+ would be +nil+ in our view, and calling
@@ -766,7 +782,8 @@ TIP: Rails automatically wraps fields that contain an error with a div
with class +field_with_errors+. You can define a css rule to make them
standout.
-Now you'll get a nice error message when saving a post without title:
+Now you'll get a nice error message when saving a post without title when you
+attempt to do just that on the "new post form(http://localhost:3000/posts/new)":http://localhost:3000/posts/new.
!images/getting_started/form_with_errors.png(Form With Errors)!
@@ -830,21 +847,23 @@ it look as follows:
<%= link_to 'Back', :action => :index %>
</erb>
-This time we point the form to the +update+ action (not defined yet).
+This time we point the form to the +update+ action, which is not defined yet
+but will be very soon.
+
The +:method => :put+ option tells Rails that we want this form to be
-submitted via +put+, which is the http method you're expected to use to
+submitted via the +PUT+, HTTP method which is the HTTP method you're expected to use to
*update* resources according to the REST protocol.
TIP: By default forms built with the +form_for_ helper are sent via +POST+.
-Moving on, we need to add the +update+ action. The file
+Next, we need to add the +update+ action. The file
+config/routes.rb+ will need just one more line:
<ruby>
put "posts/:id" => "posts#update"
</ruby>
-And the +update+ action in +posts_controller+ itself should not look too complicated by now:
+And then create the +update+ action in +app/controllers/posts_controller.rb+:
<ruby>
def update
@@ -858,7 +877,7 @@ def update
end
</ruby>
-The new method +update_attributes+ is used when you want to update a record
+The new method, +update_attributes+, is used when you want to update a record
that already exists, and it accepts an hash containing the attributes
that you want to update. As before, if there was an error updating the
post we want to show the form back to the user.
@@ -868,11 +887,11 @@ example, if you'd call +@post.update_attributes(:title => 'A new title')+
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 +index+ and
-+show+ views:
+Finally, we want to show a link to the +edit+ action in the list of all the
+posts, so let's add that now to +app/views/posts/index.html.erb+ to make it
+appear next to the "Show" link:
<erb>
-# app/view/posts/index.html.erb
<table>
<tr>
@@ -891,11 +910,16 @@ Finally, we want to show a link to the +edit+ action in the +index+ and
</tr>
<% end %>
</table>
+</erb>
-# app/view/posts/show.html.erb
+And we'll also add one to the +app/views/posts/show.html.erb+ template as well,
+so that there's also an "Edit" link on a post's page. Add this at the bottom of
+the template:
+<erb>
...
+
<%= link_to 'Back', :action => :index %>
| <%= link_to 'Edit', :action => :edit, :id => @post.id %>
</erb>
@@ -924,8 +948,8 @@ simple example:
<%= @user.about_me %>
</erb>
-The +show+ view will automatically include the content of the
-+_user_details+ view. Note that partials are prefixed by an underscore,
+The +users/show+ template will automatically include the content of the
++users/_user_details+ template. Note that partials are prefixed by an underscore,
as to not be confused with regular views. However, you don't include the
underscore when including them with the +helper+ method.
@@ -934,7 +958,7 @@ Rails":layouts_and_rendering.html guide.
Our +edit+ action looks very similar to the +new+ action, in fact they
both share the same code for displaying the form. Lets clean them up by
-using a +_form+ partial.
+using a partial.
Create a new file +app/views/posts/_form.html.erb+ with the following
content:
@@ -944,7 +968,7 @@ content:
<% if @post.errors.any? %>
<div id="errorExplanation">
<h2><%= pluralize(@post.errors.count, "error") %> prohibited
- this post from being saved:</h2>
+ this post from being saved:</h2>
<ul>
<% @post.errors.full_messages.each do |msg| %>
<li><%= msg %></li>
@@ -968,23 +992,23 @@ content:
<% end %>
</erb>
-Everything except for the +form_for+ declaration remained the same. I'll
-explain later how +form_for+ can figure out the right +action+ and
-+method+ attributes when building the form, for now let's update the
-+new+ and +edit+ views:
+Everything except for the +form_for+ declaration remained the same.
+How +form_for+ can figure out the right +action+ and +method+ attributes
+when building the form will be explained in just a moment. For now, let's update the
++app/views/posts/new.html.erb+ view to use this new partial, rewriting it
+completely:
<erb>
-# app/views/posts/new.html.erb
-
<h1>New post</h1>
<%= render 'form' %>
<%= link_to 'Back', :action => :index %>
+</erb>
+Then do the same for the +app/views/posts/edit.html.erb+ view:
-# app/views/posts/edit.html.erb
-
+<erb>
<h1>Edit post</h1>
<%= render 'form' %>
@@ -992,8 +1016,7 @@ explain later how +form_for+ can figure out the right +action+ and
<%= link_to 'Back', :action => :index %>
</erb>
-Point your browser to
-"http://localhost:3000/posts/new":http://localhost:3000/posts/new and
+Point your browser to "http://localhost:3000/posts/new":http://localhost:3000/posts/new and
try creating a new post. Everything still works. Now try editing the
post and you'll receive the following error:
@@ -1011,7 +1034,8 @@ knows that it should create new objects via POST and update them via
PUT.
If you run +rake routes+ from the console you'll see that we already
-have a +posts_path+ route, which was created automatically by Rails.
+have a +posts_path+ route, which was created automatically by Rails when we
+defined the route for the index action.
However, we don't have a +post_path+ yet, which is the reason why we
received an error before.
@@ -1034,26 +1058,37 @@ line like this:
get "posts/:id" => "posts#show", :as => :post
</ruby>
-Now you'll be able to update posts again.
+The +:as+ option tells the +get+ method that we want to make routing helpers
+called +post_url+ and +post_path+ available to our application. These are
+precisely the methods that the +form_for+ needs when editing a post, and so now
+you'll be able to update posts again.
+
+NOTE: The +:as+ option is available on the +post+, +put+, +delete+ and +match+
+routing methods also.
h4. Deleting Posts
We're now ready to cover the "D" part of CRUD, deleting posts from the
database. Following the REST convention, we're going to add a route for
-deleting posts:
+deleting posts to +config/routes.rb+:
<ruby>
-# config/routes.rb
-
delete "posts/:id" => "posts#destroy"
</ruby>
-We use the +delete+ method for destroying resources, which is mapped to
-the +destroy+ action, which is provided below:
+The +delete+ routing method should be used for routes that destroy
+resources. If this was left as a typical +get+ route, it could be possible for
+people to craft malicious URLs like this:
-<ruby>
-# app/controllers/posts_controller.rb
+<html>
+<a href='http://yoursite.com/posts/1/destroy'>look at this cat!</a>
+</html>
+We use the +delete+ method for destroying resources, and this route is mapped to
+the +destroy+ action inside +app/controllers/posts_controller.rb+, which doesn't exist yet, but is
+provided below:
+
+<ruby>
def destroy
@post = Post.find(params[:id])
@post.destroy
@@ -1063,13 +1098,15 @@ end
</ruby>
You can call +destroy+ on Active Record objects when you want to delete
-them from the dabase. Note that we don't need to add a view for this
+them from the database. Note that we don't need to add a view for this
action since we're redirecting to the +index+ action.
-Finally, add a 'destroy' link to your +index+ action to wrap everything
+Finally, add a 'destroy' link to your +index+ action template
+(+app/views/posts/index.html.erb) to wrap everything
together.
<erb>
+<h1>Listing Posts</h1>
<table>
<tr>
<th>Title</th>
@@ -1092,11 +1129,14 @@ together.
</erb>
Here we're using +link_to+ in a different way. We wrap the
-+:action+ and +:id+ attributes in a hash so that we can pass other
-arguments to +link_to+. The +:method+ and +:confirm+
++:action+ and +:id+ attributes in a hash so that we can pass those two keys in
+first as one argument, and then the final two keys as another argument. The +:method+ and +:confirm+
options are used as html5 attributes so that when the click is linked,
Rails will first show a confirm dialog to the user, and then submit the
-link with method +delete+. This is done via javascript automatically.
+link with method +delete+. This is done via the JavaScript file +jquery_ujs+
+which is automatically included into your application's layout
+(+app/views/layouts/application.html.erb+) when you generated the application.
+Without this file, the confirmation dialog box wouldn't appear.
!images/getting_started/confirm_dialog.png(Confirm Dialog)!
@@ -1136,7 +1176,7 @@ end
</ruby>
If you run +rake routes+, you'll see that all the routes that we
-declared before are still available, and the app still works as before.
+declared before are still available:
<shell>
# rake routes
@@ -1150,18 +1190,22 @@ edit_post GET /posts/:id/edit(.:format) posts#edit
root / welcome#index
</shell>
+Also, if you go through the motions of creating, updating and deleting
+posts the app still works as before.
+
TIP: In general, Rails encourages the use of resources objects in place
-of declaring routes manually. For more information about routing, see
+of declaring routes manually. It was only done in this guide as a learning
+exercise. For more information about routing, see
"Rails Routing from the Outside In":routing.html.
h3. Adding a Second Model
It's time to add a second model to the application. The second model will handle comments on
-blog posts.
+posts.
h4. Generating a Model
-We're going to se the same generator that we used before when creating
+We're going to see the same generator that we used before when creating
the +Post+ model. This time we'll create a +Comment+ model to hold
reference of post comments. Run this command in your terminal:
@@ -1321,7 +1365,7 @@ So first, we'll wire up the Post show template
<p>
<strong>Text:</strong>
- <%= @post.texthttp://beginningruby.org/ %>
+ <%= @post.text %>
</p>
<h2>Add a comment:</h2>
@@ -1344,7 +1388,10 @@ So first, we'll wire up the Post show template
</erb>
This adds a form on the +Post+ show page that creates a new comment by
-calling the +CommentsController+ +create+ action. Let's wire that up:
+calling the +CommentsController+ +create+ action. The +form_for+ call here uses
+an array, which will build a nested route, such as +/posts/1/comments+.
+
+Let's wire up the +create+:
<ruby>
class CommentsController < ApplicationController
@@ -1380,7 +1427,7 @@ template. This is where we want the comment to show, so let's add that to the
<p>
<strong>Text:</strong>
- <%= @post.texthttp://beginningruby.org/ %>
+ <%= @post.text %>
</p>
<h2>Comments</h2>
@@ -1428,7 +1475,7 @@ use partials to clean it up.
h4. Rendering Partial Collections
-First we will make a comment partial to extract showing all the comments for the
+First, we will make a comment partial to extract showing all the comments for the
post. Create the file +app/views/comments/_comment.html.erb+ and put the
following into it:
@@ -1455,7 +1502,7 @@ following:
<p>
<strong>Text:</strong>
- <%= @post.texthttp://beginningruby.org/ %>
+ <%= @post.text %>
</p>
<h2>Comments</h2>
@@ -1517,7 +1564,7 @@ Then you make the +app/views/posts/show.html.erb+ look like the following:
<p>
<strong>Text:</strong>
- <%= @post.texthttp://beginningruby.org/ %>
+ <%= @post.text %>
</p>
<h2>Add a comment:</h2>