Pacecar adds scope methods and other common functionality to ActiveRecord classes via database column introspection.
Pacecar automatically includes the Pacecar::Helpers module into all ActiveRecord::Base classes.
To get all Pacecar functionality, you need to "include Pacecar" in your class.
class User < ActiveRecord::Base
include Pacecar
end
To get some subset (for example, only the state functionality), you can do something like "include Pacecar::State" to get only the module(s) you want.
class Post < ActiveRecord::Base
include Pacecar::State
end
Pacecar supports mysql, postgres and sqlite database drivers, and is compatible with Rails 3.0.x and 3.1.x versions.
For rails 3, just include in your Gemfile
gem 'pacecar'
For prior rails versions, there is a rails2 branch to use:
gem 'pacecar', :git => 'git://github.com/thoughtbot/pacecar.git', :branch => 'rails2'
Assuming a database schema:
class CreateSchema < ActiveRecord::Migration
def self.up
create_table :users, :force => true do |t|
t.boolean :admin, :default => false, :null => false
t.datetime :approved_at
t.datetime :rejected_at
t.string :first_name
t.string :last_name
t.text :description
t.timestamps
end
create_table :posts, :force => true do |t|
t.string :owner_type
t.integer :owner_id
t.string :publication_state
t.string :post_type
t.timestamps
end
create_table :comments, :force => true do |t|
t.integer :user_id
t.text :description
t.integer :rating
t.timestamps
end
end
end
And some basic model declarations:
class User < ActiveRecord::Base
include Pacecar
has_many :posts, :as => :owner
has_many :comments
has_many :articles
has_ranking :comments
has_recent_records :comments
has_recent_records :articles, :comments
has_calculated_records :comments, :on => :rating
end
class Post < ActiveRecord::Base
include Pacecar
PUBLICATION_STATES = %w(Draft Submitted Rejected Accepted)
TYPES = %w(Free Open Private Anonymous PostModern)
belongs_to :owner, :polymorphic => true
has_state :publication_state
has_state :post_type, :with => TYPES
has_polymorph :owner
end
class Comment < ActiveRecord::Base
include Pacecar
belongs_to :user
end
class Article < ActiveRecord::Base
belongs_to :user
end
Records where approved_at is not null, or where it is null:
User.approved_at_present
User.approved_at_missing
Records where first_name is not null, or where it is null:
User.first_name_present
User.first_name_missing
Records ordered by first_name (default to 'asc', can specify to override):
User.by_first_name
User.by_first_name(:asc)
User.by_first_name(:desc)
Records where an attribute matches a search term (column LIKE "%term%"):
User.first_name_matches('John')
Records where an attribute starts or ends with a search term:
User.first_name_starts_with('A')
User.first_name_ends_with('a')
Records where an attribute matches exactly a term:
User.first_name_equals('John')
Records where any non-state text or string column matches term:
User.search_for('test')
Records where any of a list of columns match the term:
User.search_for 'test', :on => [:first_name, :last_name]
Records where all of a list of columns match the term:
User.search_for 'test', :on => [:first_name, :last_name], :require => :all
Records that are all admins or non-admins:
User.admin
User.not_admin
The "balance" (count of true minus false for column in question):
User.admin_balance
Records approved before or after certain times:
User.approved_at_before(5.days.ago)
User.approved_at_after(4.weeks.ago)
Records with approved_at in the past or future:
User.approved_at_in_past
User.approved_at_in_future
Records with approved_at inside or outside of two times:
User.approved_at_inside(10.days.ago, 1.day.ago)
User.approved_at_outside(2.days.ago, 1.day.ago)
Records with certain year, month or day:
User.approved_at_in_year(2000)
User.approved_at_in_month(01)
User.approved_at_in_day(01)
Records with a duration (time delta between two columns) of, over or under a certain number of days:
User.with_duration_of(14, :approved_at, :rejected_at)
User.with_duration_over(14, :approved_at, :rejected_at)
User.with_duration_under(14, :approved_at, :rejected_at)
Records which have an owner_type of User:
Post.for_owner_type(User)
Records with the most and least associated records:
User.maximum_comments
User.minimum_comments
Records with associated records since a certain time:
User.recent_comments_since(2.days.ago)
User.recent_comments_and_posts_since(3.days.ago)
User.recent_comments_or_posts_since(4.days.ago)
Records with highest and lowest association column average:
User.by_comments_highest_rating_average
User.by_comments_lowest_rating_average
Records with highest and lowest association column total:
User.by_comments_highest_rating_total
User.by_comments_lowest_rating_total
Records which are in a particular state, or not in a state:
Post.publication_state_draft
Post.post_type_not_open
Query methods on instances to check state:
Post.first.publication_state_draft?
Post.last.post_type_not_open?
Records which are greater than or less than a certain value:
User.age_greater_than(21)
User.age_greater_than_or_equal_to(21)
User.age_less_than(21)
User.age_less_than_or_equal_to(21)
First x records:
User.limited(10)
Because these are all scope, you can combine them.
To get all users that have a first_name set, who are admins and approved more than 2 weeks ago, ordered by their first name:
User.first_name_present.admin.approved_at_before(2.weeks.ago).by_first_name
To get the top 10 commenters:
User.maximum_comments.limited(10)
- MySQL
- SQLite
- Postgres
Pacecar is maintained and funded by thoughtbot, inc
Thank you to all the contributors!
The names and logos for thoughtbot are trademarks of thoughtbot, inc.
Pacecar is Copyright © 2008-2011 thoughtbot. It is free software, and may be redistributed under the terms specified in the MIT-LICENSE file.