unitwise-rails

unitwise-rails is a gem that provides rails extension to the the refined unitwise gem.

Installation

Add this line to your application's Gemfile:

gem 'unitwise-rails', github: 'maximebedard/unitwise-rails'

Migrations

# Add the fields :protein_value and :protein_unit when the
# migration is executed.
class AddUnitToIngredients < ActiveRecord::Migration
  def self.up
    add_unit :ingredients, :protein
  end

  def self.down
    remove_unit :ingredients, :protein
  end
end

class CreateIngredients < ActiveRecord::Migration
  def change
    create_table :ingredients do |t|
      t.string :name
      t.unit :protein
      t.timestamps
    end
  end
end

Models

# Add a method #protein to the model that will always be converted to grams
class Ingredient < ActiveRecord::Base
  # Add unit with automatic conversion to grams before save
  unit_for :protein, convert_to: :gram

  # Add unit with compatibility validation
  unit_for :carbohydrate
  validates_unit_compatibility_of :carbohydrate, with: :gram
  validates_unit_presence_of :carbohydrate

  # or
  validates_unit :carbohydrate, presence: true, compatibility: :gram
end

TODOs

• Add unit_for extension to ActiveRecord::Base
• Add unit generation to migrations
• Add validates_unit validator
• Add validates_unit_compatibility_of validator
• Add validates_unit_presence_of validator
• Add Unitwise::Rails::Migration tests