SimplestStatus

SimplestStatus is a gem built to provide simple, convenient status functionality for Rails models. It's designed to work with practically every version of Rails (tested as far back as 2.0.5) and will work with Ruby 1.9.3 and up.

SimplestStatus is similar to the recently introduced enum (debuted in Rails 4.1), but is different in that it doesn't rely on a particular version of Rails, it's geared specifically toward status columns, and it provides additional functionality like constant-based status lookup, label helpers, and validations.

Installation

Add this line to your application's Gemfile:

gem 'simplest_status'

And then execute:

$ bundle

Or install it yourself as:

$ gem install simplest_status

Usage

Add an integer-type status field to a model with :null => false and :default => 0:

class AddStatusToPostsMigration < ActiveRecord::Migration
  def change
    add_column :posts, :status, :integer, :null => false, :default => 0
  end
end

Then in your model, extend SimplestStatus and list out your statuses:

class Post < ActiveRecord::Base
  extend SimplestStatus

  statuses :draft, :preview, :published, :archived
end

This will generate a number of constants, methods, and model validations.

Status List

Post.statuses # => { :draft => 0, :preview => 1, :published => 2, :archived => 3 }

The returned hash is a StatusCollection that, when iterated over, yields Status objects:

Post.statuses.first.tap do |status|
  status.name          # => :draft
  status.value         # => 0
  status.string        # => 'draft'
  status.to_hash       # => { :draft => 0 }
  status.constant_name # => 'DRAFT'
  status.label         # => 'Draft'
  status.for_select    # => ['Draft', 0]
end

It also provides a helper method for usage in a form select:

Post.statuses.for_select # => [['Draft', 0], ['Preview', 1], ['Published', 2], ['Archived', 3]]

Constants

Instead of referring to status values by the underlying integer, SimplestStatus generates constants for this purpose:

Post::DRAFT     # => 0
Post::PREVIEW   # => 1
Post::PUBLISHED # => 2
Post::ARCHIVED  # => 3

Scopes

Post.draft
Post.preview
Post.published
Post.archived

Predicate Methods

Post.new(:status => Post::DRAFT) do |post|
  post.draft?     # => true
  post.preview?   # => false
  post.published? # => false
  post.archived?  # => false
end

Status Mutation Methods

Post.new(:status => Post::ARCHIVED) do
  post.draft      # status from Post::ARCHIVED to Post::DRAFT
  post.preview    # status from Post::DRAFT to Post::PREVIEW
  post.published  # status from Post::PREVIEW to Post::PUBLISHED
  post.archived   # status from Post::PUBLISHED to Post::ARCHIVED
end

Status Label Method

Post.new(:status => Post::DRAFT).status_label     # => 'Draft'
Post.new(:status => Post::PREVIEW).status_label   # => 'Preview'
Post.new(:status => Post::PUBLISHED).status_label # => 'Published'
Post.new(:status => Post::ARCHIVED).status_label  # => 'Archived'

Status Validations

SimplestStatus will automatically add the following validations:

validates :status, :presence => true, :inclusion => { :in => proc { statuses.values } }