Acts As Scoped Rails Plugin

Posted by acts_as_flinn Thu, 19 Jul 2007 16:15:00 GMT

I’m pleased to announce the public availability of the acts_as_scoped plugin.

From the README:

This plugin wraps find in a scope based on a persistent variable. This enables you to use something like the userstamp plugin to ensure a model’s find method returns objects scoped within the current user.

Documentation

http://saas.rubyforge.org/acts_as_scoped

Rubyforge Project

http://rubyforge.org/projects/saas

Usage


# You'll need to add a user_id column to the sandwiches table

class Sandwich < ActiveRecord::Base
  acts_as_scoped :user # belongs_to is included
end


class User < ActiveRecord::Base
  cattr_accessor :current
  has_many :sandwiches
end


class ApplicationController < ActionController::Base 
...
  before_filter :current_user

  def current_user
    User.current = User.find(session[:user_id]) unless session[:user_id].blank?
  end
...

Installation

script/plugin install svn://rubyforge.org/var/svn/saas/acts_as_scoped/trunk/acts_as_scoped

Software as a Service

The plugin is part of the Software as a Service project on Rubyforge. You can use this plugin in conjunction with something similar to the userstamp plugin to automagically limit the scope of your find, calculate, save, delete methods. It is used with other plugins as a drop in that will allow you to turn just about any rails application into a software as a service.

acts_as_breadcrumbs

Posted by acts_as_flinn Wed, 02 May 2007 04:32:00 GMT

Breadcrumbs on Rails

In a few programs that I have worked on in recent months I have had a need to build models using acts_as_tree either for building a URL, Breadcrumbs, or a Location String for picking inventory. They all have something in common, in order to build the string properly they relied on acts_as_tree and used two recursive methods to traverse the tree to essentially create a breadcrumbs pattern in one for or another.

“You Are Here”

So I decided to extract the meaningful bits of code and create a small plugin that adds breadcrumbs methods to ActiveRecord. The result is acts_as_breadcrumbs.

It’s very easy to use, provide a “breadcrumbs” column to store the resulting breadcrumbs string (yes store, we’re not building it on the fly), and provide a basename column to build the string.

Docs

http://breadcrumbs.rubyforge.org

Installation

  • script/plugin install svn://rubyforge.org/var/svn/breadcrumbs/trunk/acts_as_breadcrumbs

Examples

class Location < ActiveRecord::Base
  acts_as_tree
  acts_as_breadcrumbs(:attr => :location_string)
end

some_location = Location.new(:name => "RM03", :parent => first_floor, :description => "Room 3 on the First Floor")
some_location.location_string #=> "HQ:FL01:RM03"

The above example creates an address for picking inventory.

class Soldier < ActiveRecord::Base
  acts_as_tree
  acts_as_breadcrumbs(:attr => :chain_o_command, :separator => " > ")
end

mueller = Soldier.new(:name => "LTC Mueller", :parent => stanley)
mueller.chain_o_command #=> "General Hailstone > Colonel Stanley > LTC Mueller"

This example creates a chain of command excluding the root object(The President).

class WebPage < ActiveRecord::Base
  include ActionView::Helpers::TagHelper

  acts_as_tree
  acts_as_breadcrumbs(:attr => :url, :basename => :slug, :separator => "/")
  acts_as_breadcrumbs(:basename => :link, :separator => "&nbsp;&gt;&nbsp;")

  # from urlnameable
  def slug
    t = self.title.to_s.downcase.strip.gsub(/[^-\s[:alnum:]]/, ’’).squeeze(’ ‘).tr(’ ‘, ‘‘)
    (t.blank?) ? ’_’ : t
  end

  def link
    content_tag ‘a’, self.title, :href => "#{self.url}"
  end
end

baz = WebPage.create(:title => "Baz", :parent => bar)
baz.url         #=> ‘foo/bar/baz’
baz.breadcrumbs #=> ’<a href="foo">Foo</a>&nbsp;&gt;&nbsp;<a href="foo/bar">Bar</a>&nbsp;&gt;&nbsp;<a href="foo/bar/baz">Baz</a>’

The last example uses two breadcrumbs attributes, one to generate a URL (yes it’s a hack but fun for example purposes) and another to create a breadcrumbs string.

Note: in my examples I use hypothetical existing objects

Bug Warning

This is the first release, so please let me know if you find bugs. Achtung! if you set the parent_id = id you get a cartesian product (ie. a never ending loop), I might add a validator to ensure parent_id != id.