Ruby on Rails Global Activerecord::Enum

Ruby on Rails Global ActiveRecord::Enum

Use ActiveSupport::Concern this feature created for drying up model codes:

#app/models/concerns/my_enums.rb
module MyEnums
  extend ActiveSupport::Concern

  included do
    enum status: [:active, :inactive, :deleted]
  end
end

# app/models/my_model.rb
class MyModel < ActiveRecord::Base
  include MyEnums
end

# app/models/other_model.rb
class OtherModel
  include MyEnums
end

Read more

Rails global enums?

It may be less likely that I need to
access it in my model, but definitely
within the controller and view.

Are you sure? When you talk about database and schema, you are talking about the Model part of your application.
I think the best place to store these variables would be the model that uses them.

If these variables belongs to a single model you can store them directly in the model itself:

class Item < ActiveRecord::Base
  STATUS_UNKNOWN = 0
  STATUS_MEDICAL = 3
end

Then you can reference the values inside and outside the model scope

class Item
  def my_method
    STATUS_UNKNOWN
  end
end

Item::STATUS_UNKNOWN # => 0
Item.new.my_method # => 0

When there is an enumeration of values, Rubyists often use hashes or arrays.

class Item
  AVAILABLE_STATUSES = { :unkwnown => 0, :medical => 3 }

  def self.statuses
    self.AVAILABLE_STATUSES.keys.sort
  end

  def self.status_value(key)
    self.AVAILABLE_STATUSES[:key]
  end

end

Item::AVAILABLE_STATUS # => { :unkwnown => 0, :medical => 3 }
Item.statuses # => [:medical, :unkwnown]
Item.status_value(:medical) # => 3

If more than one model share the same logic, you can put it in a Module and mix the module in all Models that requires it.

Proper storage of enumeration models in Rails

Check out the ruby gem I've been working on called classy_enum. I'm pretty sure it does exactly what you're looking for. The README has some example usage, but the premise is that it lets you define multiple enum members as classes that can have different properties.

How to build dynamic enums in Rails 6 model concerns?

There are cleaner ways to do what I'm about to present, but it will accomplish what you're trying to do. Mind the brevity (I removed your associations to do a quick spot-check on my machine):

module Bookable
  extend ActiveSupport::Concern
  included do 
    STAGES = {
      confirmed: 0,
      completed: 1,
      cancelled: 2,
      issue_raised: 3
    }.freeze
  end 
end

class ApplicationRecord < ActiveRecord::Base 
  self.abstract_class = true 

  def self.acts_as_bookable_with(extra_stages = {})
    include Bookable

    enum stage: self::STAGES.merge(extra_stages)
  end
end 

class Mission < ApplicationRecord
  acts_as_bookable_with({
      awaiting_estimate: 4,
      awaiting_payment: 5,
      awaiting_report: 6,
      report_sent: 7
    })
end

If you want to define these on the class, it would look like this:

module Bookable
  extend ActiveSupport::Concern
  included do 
    STAGES = {
      confirmed: 0,
      completed: 1,
      cancelled: 2,
      issue_raised: 3
    }.freeze
  end 
end

class ApplicationRecord < ActiveRecord::Base 
  self.abstract_class = true 

  def self.acts_as_bookable_with(extra_stages)
    include Bookable
    if extra_stages.is_a?(Symbol)
      extra_stages = self.send(extra_stages)
    elsif extra_stages.is_a?(Hash)
      # do nothing
    else
      raise TypeError, "can't find extra_stages from #{extra_stages.inspect}"
    end
    stages = self::STAGES.merge(extra_stages)
    enum stage: stages
  end
end 

class Comment < ApplicationRecord
  def self.extra_stages
    {
      awaiting_estimate: 4,
      awaiting_payment: 5,
      awaiting_report: 6,
      report_sent: 7
    }
  end

  acts_as_bookable_with(:extra_stages)

end

Note that we're calling acts_as_bookable_with after we define our class method. Otherwise, we'll get undefined method error.

There isn't a whole lot of "bad" in having this in ApplicationRecord. It's not the most ideal way of doing it, but most of these acts_as_* modules follow this exact pattern anyway and inject into ActiveRecord::Base.

Rails: How do I validate uniqueness of certain types in an enum

validates :account_type, uniqueness: true, if: 'account_type == "user"'

The answer was based on @neydroid's answer, although that per se was incorrect, and he didn't respond to my request to fix it.

Ruby on Rails: get variable from include do

You cannot include this module into your controller. You could however try:

module MyEnums
  extend ActiveSupport::Concern
  Statuses = [:active, :inactive, :deleted]

  included do
    enum status: Statuses
  end

end

And then in the controller:

MyEnums::Statuses

---

Related Topics