How to share constants between controller and model Ruby on Rails

Question

Is it possible to share constants between controller and model?

e.g. in product.rb I have

PRODUCT_TYPES = %w[one two]

I want PRODUCT_TYPES constant to be available in the controllers as well.

Answer 1

As per my consideration your Product model looks like

 class Product < ActiveRecord::Base
      PRODUCT_TYPES = %w[one two]
 end

You can access the given constant in the controller as below

p.product_type == Product::PRODUCT_TYPES[:one]

Answer 2

I deeply explained the various possibility in this answer

You basically have 3 possibilities:

• global scope (initializer)
• application scope (using the application module created by Rails)
• class scope (defined them where you want, and call them with Class::CONSTANT)

Answer 3

We can access model constant in Controller as bellow...

class Invoice < ActiveRecord::Base
       STATUS_PAYABLE          = %w(APPROVED OPEN)
 end

Controller use like ..

 Invoice::STATUS_PAYABLE.include?('OPEN')