GroupedScope: Has Many Associations IN (GROUPS)
GroupedScope aims to make two things easier in your ActiveRecord models. First, provide a easy way to group objects, second, to allow the group to share associated object via existing has_many relationships. See installation and usage for more details.
By the way, this plugin has been tested with rails 1.2.6, 2.0.4, and 2.1.1.
Installation & Usage
From your project's RAILS_ROOT, run:
./script/plugin install git://github.com/metaskills/grouped_scope.git
To use GroupedScope on a model it must have a :group_id column.
class AddGroupId < ActiveRecord::Migration def self.up add_column :employees, :group_id, :integer end def self.down remove_column :employees, :group_id end end
Assume the following model.
class Employee < ActiveRecord::Base has_many :reports grouped_scope :reports end
By calling grouped_scope on any association you create a new group accessor for each instance. The object returned will act just like an array and at least include the current object that called it.
@employee_one.group # => [#<Employee id: 1, group_id: nil>]
To group resources, just assign the same :group_id in the schema. Note that in future versions I will be extending the GroupedScope::Grouping that each object belongs to. If you do not just want to assign some random integers, then take a look at that model and the belongs_to :grouping code, schema needed ofcourse
@employee_one.update_attribute :group_id, 1 @employee_two.update_attribute :group_id, 1 @employee_one.group # => [#<Employee id: 1, group_id: 1>, #<Employee id: 2, group_id: 1>]
Calling grouped_scope on the :reports association leaves the existing association intact.
@employee_one.reports # => [#<Report id: 2, employee_id: 1>] @employee_two.reports # => [#<Report id: 18, employee_id: 2>, #<Report id: 36, employee_id: 2>]
Now the good part, all associations passed to the grouped_scope method can be called on the group proxy. The collection will return resources shared by the group.
@employee_one.group.reports # => [#<Report id: 2, employee_id: 1>, #<Report id: 18, employee_id: 2>, #<Report id: 36, employee_id: 2>]
You can even call named scopes defined on the objects in the collection and association extensions defined on the original has_many. For instance:
Go back and start adding some rdocs.
Add more GroupedScope::Grouping code.
Add polymorphic support.
Raise errors and/or support :finder_sql/:counter_sql.
Add a user definable group_id schema.
Helping Our & Running Tests
Running the test suite is easy to do. Just make sure you have the following gems installed.
If you want to run the tests for a specific version of rails in gems (other than the latest), then you can set the RAILS_VERSION environment variable. For example `env RAILS_VERSION=1.2.6 autotest`. When doing this you also need to make sure that you download version 4.1 of shoulda (not the gem) and place its lib contents into `test/lib/shoulda` and `test/lib/shoulda.rb`. The reason is that the latest should gem require ActiveSupport greater than 2.0.
Copyright © 2008 Ken Collins, Decisiv Inc. Released under the MIT license.