dkubb-resource_controller

= Resource Controller

resource_controller makes RESTful controllers easier, more maintainable, and super readable. With the RESTful controller pattern hidden away, you can focus on what makes your controller special.

== Get It

Install it as a plugin:

script/plugin install git://github.com/giraffesoft/resource_controller.git

Or grab the source

git clone git://github.com/giraffesoft/resource_controller.git

= Usage

Creating a basic RESTful controller is as easy as...

class PostsController < ResourceController::Base end

...or if you prefer, you can use the method-call syntax. If you need to inherit from some other class, this syntax is definitely for you:

class PostsController < ApplicationController resource_controller end

Both syntaxes are identical in their behavior. Just make sure you call resource_controller before you use any other r_c functionality in your controller.

Nobody just uses the default RESTful controller, though. resource_controller provides a simple API for customizations.

== Action Lifecycle

It's really easy to make changes to the lifecycle of your actions.

Note: We had to call the new accessor "new_action", since new is somewhat reserved in ruby.

=== Before and After

class ProjectsController < ResourceController::Base

new_action.before do
  3.times { object.tasks.build }
end

create.after do
  object.creator = current_user
end

end

=== Flash

class ProjectsController < ResourceController::Base create.flash "Can you believe how easy it is to use resource_controller? Neither could I!" end

=== respond_to

You can add to what's already there...

class ProjectsController < ResourceController::Base
create.wants.js { render :template => "show.rjs" } end

Or you can create a whole new block. This syntax destroys everything that's there, and starts again...

class ProjectsController < ResourceController::Base
create.response do |wants| wants.html wants.js { render :template => "show.rjs" } end end

If you have a nested resource and want to redirect to the parent after create/update and destroy you can do this in the object controller

class CommentsController < ResourceController::Base belongs_to :post

create.wants.html { redirect_to smart_url(parent_url_options) } 
update.wants.html { redirect_to smart_url(parent_url_options) } 
destroy.wants.html { redirect_to smart_url(parent_url_options) }

end

=== Scoping

Because sometimes you want to make a bunch of customizations at once, most of the helpers accept blocks that make grouping calls really easy. Is it a DSL? Maybe; maybe not. But, it's definitely awesome.

With actions that can fail, the scoping defaults to success. That means that create.flash == create.success.flash.

class ProjectsController < ResourceController::Base

create do
  flash "Object successfully created!"
  wants.js { render :template => "show.rjs" }
  
  failure.wants.js { render :template => "display_errors.rjs" }
end

destroy do
  flash "You destroyed your project.  Good work."
  
  failure do
    flash "You cannot destroy that project.  Stop trying!"
    wants.js { render :template => "display_errors.rjs" }
  end
end

end

== Singleton Resource

If you want to create a singleton RESTful controller inherit from ResourceController::Singleton.

class AccountsController < ResourceController::Singleton end

...or if need to inherit from some other class:

class AccountsController < ApplicationController resource_controller :singleton end

Note: This type of controllers handle a single resource only so the index action and all the collection helpers (collection_url, collection_path...) are not available for them.

Loading objects in singletons is similar to plural controllers with one exception. For non-nested singleton controllers you should override the object method as it defaults to nil for them.

class AccountsController < ResourceController::Singleton private def object @object ||= Account.find(session[:account_id]) end end

In other cases you can use the default logic and override it only if you use permalinks or anything special.

Singleton nesting with both :has_many and :has_one associations is provided...

map.resource :account, :has_many => :options # /account/options, account is a singleton parent map.resources :users, :has_one => :image # /users/1/image, image is a singleton child

If you have the :has_many association with a singleton parent remember to override parent_object for your :has_many controller as it returns nil by default in this case.

class OptionsController < ResourceController::Base belongs_to :account

protected
def parent_object
  Account.find(session[:account_id])
end

end

== Helpers (ResourceController::Helpers)

=== Loading objects

You want to add something like pagination to your controller...

class PostsController < ResourceController::Base private def collection @collection ||= end_of_association_chain.find(:all, :page => {:size => 10, :current => params[:page]}) end end

Or maybe you used a permalink...

class PostsController < ResourceController::Base private def object @object ||= end_of_association_chain.find_by_permalink(param) end end

=== Building objects

Maybe you have some alternative way of building objects...

class PostsController < ResourceController::Base private def build_object @object ||= end_of_association_chain.build_my_object_some_funky_way object_params end end

...and there are tons more helpers in the ResourceController::Helpers

== Nested Resources

Nested controllers can be a pain, especially if routing is such that you may or may not have a parent. Not so with Resource Controller.

class CommentsController < ResourceController::Base belongs_to :post end

All of the finding, and creation, and everything will be done at the scope of the post automatically.

== Namespaced Resources

...are handled automatically, and any namespaces are always available, symbolized, in array form @ ResourceController::Helpers#namespaces

== Polymorphic Resources

Everything, including url generation is handled completely automatically. Take this example...

comment.rb

class Comment belongs_to :commentable, :polymorphic => true end

comments_controller.rb

class CommentsController < ResourceController::Base belongs_to :post, :product, :user end Note: Your model doesn't have to be polymorphic in the ActiveRecord sense. It can be associated in whichever way you want.

routes.rb

map.resources :posts, :has_many => :comments map.resources :products, :has_many => :comments map.resources :users, :has_many => :comments

All you have to do is that, and r_c will infer whichever relationship is present, and perform all the actions at the scope of the parent object.

=== Parent Helpers

You also get some helpers for reflecting on your parent.

parent? # => true/false is there a parent present? parent_type # => :post parent_model # => Post parent_object # => @post

=== Non-standard resource names

resource_controller supports overrides for every non-standard configuration of resources.

The most common example is where the resource has a different name than the associated model. Simply overriding the model_name helper will get resource_controller working with your model.

map.resources :tags ... class PhotoTag < ActiveRecord::Base ... class TagsController < ResourceController::Base private def model_name 'photo_tag' end end

In the above example, the variable, and params will be set to @tag, @tags, and params[:tag]. If you'd like to change that, override object_name.

def object_name 'photo_tag' end

If you're using a non-standard controller name, but everything else is standard, overriding resource_name will propagate through all of the other helpers.

map.resources :tags, :controller => "somethings" ... class Tag < ActiveRecord::Base ... class SomethingsController < ResourceController::Base private def resource_name 'tag' end end

Finally, the route_name helper is used by Urligence to determine which url helper to call, so if you have non-standard route names, override it.

map.resources :tags, :controller => "taggings" ... class Taggings < ActiveRecord::Base ... class TaggingsController < ResourceController::Base private def route_name 'tag' end end

== Url Helpers

Thanks to Urligence, you also get some free url helpers.

No matter what your controller looks like...

[edit_|new_]object_url # is the equivalent of saying [edit_|new_]post_url(@post) [edit_|new_]object_url(some_other_object) # allows you to specify an object, but still maintain any paths or namespaces that are present

collection_url # is like saying posts_url

Url helpers are especially useful when working with polymorphic controllers.

/posts/1/comments

object_url # => /posts/1/comments/#{@comment.to_param} object_url(comment) # => /posts/1/comments/#{comment.to_param} edit_object_url # => /posts/1/comments/#{@comment.to_param}/edit collection_url # => /posts/1/comments

/products/1/comments

object_url # => /products/1/comments/#{@comment.to_param} object_url(comment) # => /products/1/comments/#{comment.to_param} edit_object_url # => /products/1/comments/#{@comment.to_param}/edit collection_url # => /products/1/comments

/comments

object_url # => /comments/#{@comment.to_param} object_url(comment) # => /comments/#{comment.to_param} edit_object_url # => /comments/#{@comment.to_param}/edit collection_url # => /comments

Or with namespaced, nested controllers...

/admin/products/1/options

object_url # => /admin/products/1/options/#{@option.to_param} object_url(option) # => /admin/products/1/options/#{option.to_param} edit_object_url # => /admin/products/1/options/#{@option.to_param}/edit collection_url # => /admin/products/1/options

You get the idea. Everything is automagical! All parameters are inferred.

== Credits

resource_controller was created, and is maintained by {James Golick}[http://jamesgolick.com].

== License

resource_controller is available under the {MIT License}[http://en.wikipedia.org/wiki/MIT_License]