API: Action Link

Action Links are used to tie pieces of ActiveScaffold together, and can be used to integrate your own functionality. They can be attached and configured in a variety of places. Native actions like Create, Update, and Delete have configurable links within their own config sections (e.g. config.create.link), and column objects may themselves have an action link (e.g. config.columns[:username].link). The main config.action_links collection is meant for your custom links.

action

The :action value of the URL

confirm

The confirmation message for the link, if any.

controller v1.1

Lets you specify a different controller for the action link. In version 1.0 you had to sneak this in through the :parameters option.

crud_type

Specifies that the (eventual) CRUD action initiated by this link will be one of the core CRUD types. This is used to check authorization and disable the link.

Values: :create, :read, :update, :destroy

dhtml_confirm

Set to a class instance implementing the dhtml confirmation. It must be a subclass of DHTMLConfirm class, overriding onclick_handler method with javascript code which triggers the DHTML confirmation logic.

config.delete.link.dhtml_confirm = ModalboxConfirm.new

html_options

Html attributes to render this action link

inline

When true, the link will open with an AJAX call, using the :position option.

Values: true, false

label

The visible text for the link.

method

Specifies a method for RESTful links. Default is :get.

Values: :get, :post, :put, :delete

page

When true, the link will open with standard HTML behavior.

Values: true, false

parameters

Miscellaneous parameters for the URL. In version 1.0, if you want to link to another controller you need to specify a :controller parameter here.

popup

When true, the link will open in a new window. Currently there is no configuration option to set the size of the new window.

Values: true, false

position

For inline links, determines where the result goes. When set to false, then ActiveScaffold will not try to automatically place the result (good for RJS responses, or e.g. in cases, where the action involved is not expected to return a view).

Values:

• for :type => :collection: :top, false.
• for :type => :member: :replace, :after, :before, and false.

security_method

Specifies a method on the controller that determines whether to show this link or not. Note that this does NOT prevent someone from URL hacking.

Values: a symbol naming the method (e.g. :logged_in?)

type

Determines whether the link appears on each record, or just once for the entire scaffold.

Values: :collection, :member

Before v2.3, values: :table, :record

Examples:

config.show.link = false     #This removes the show link from the list view, but still allows the show function to be used.
config.update.link.inline = false     #This sets the update link to open in its own page.

To enable or disable action links on a per record basis:

Create an authorized_for_#{action}? (e.g. authorized_for_destroy?) in your model and return false for disabling the action link based on your conditions. You can create two methods for column level security checks for every CRUD action, such as #{column}_authorized_for? or #{column}_authorized_for_#{action}?.

class MyModel < ActiveRecord::Base
  def authorized_for_delete?
     false
  end
  def authorized_for_update?
     false
  end
end

You can override the authorized_for? method in your model and return false for disabling action_links based on your conditions, but then you can’t use #{column}_authorized_for?, authorized_for_#{action}? or #{column}_authorized_for_#{action}?. For action_links do something like this:

class MyModel < ActiveRecord::Base
  def authorized_for?(*args)
     not [:destroy, :update].include?(args[0][:action]) 
  end
end

Example: Adding “To PDF” Action Link

To the routes.rb file add the following:

resources :orders do 
  member do
    get 'to_pdf'
  end
  as_routes 
end

This will add an /orders/:id/to_pdf(.:format) route.

To the controller add the following:

active_scaffold :order do |conf|
  conf.action_links.add 'to_pdf', :label => 'To PDF', :page => true, :type => :member, :parameters => {:format => 'pdf'}
end

def to_pdf
  @order = Order.find(params[:id])
end

Then use something like prawn_rails and create a to_pdf.pdf.prawn view to render your PDF output.