SymbolicAttribute

Ruby on Rails ActiveRecord helper to deal with constants stored in database

Add a symoblic_attribute method to ActiveRecord::Base, which

• overrides the instance attribute getter to symbolize its value
• if a :values option key is passed with an array as value, it defines a class attribute attribute_name.pluralize which stores the available attribute values and validates the inclusion of any new instance attribute value within this same array

Installation

Add this line to your application's Gemfile:

gem 'symbolic_attribute'

And then execute:

$ bundle

Or install it yourself as:

$ gem install symbolic_attribute

Usage

symoblic_attribute(attr_name, options)

• attribute_name (String)
• options (String)
  • :values (Array): list the available attribute values, will be stored in a attribute_name.pluralize class attribute
  • other hash keys and values are passed to validates attribute_name method, usefull to set some conditional validation (refer to the example bellow)

class Participation < ActiveRecord::Base
  symbolic_attribute :role, 
    values: %i{buyer seller}, 
    allow_nil: true
end

#Outside ActiveRecord, we need to implement an attribute accessor and the read_attribute method used by ActiveModel::Validation 
class Participation 
  symbolic_attribute :role, 
    values: %i{buyer seller}, 
    allow_nil: true


  attr_accessor :role

  def read_attribute(attr)
    instance_variable_get :"@#{attr}"
  end

end


Participation.roles
> [:buyer, :seller]

participation = Participation.new

participation.save
> true

participation.role = "foo"

participation.save
> false

Contributing

Bug reports and pull requests are welcome on GitHub at https://github.com/[USERNAME]/symbolic_attribute. This project is intended to be a safe, welcoming space for collaboration, and contributors are expected to adhere to the Contributor Covenant code of conduct.

License

The gem is available as open source under the terms of the MIT License.