Globals don't need to be just variables

• Wrap global variables in Current class

  class Current < ActiveSurpport::CurrentAttributes
    attribute :account, :person
    attribute :request_id, :user_agent, :ip_address
  
    delegate :user, :integration, to: :person, allow_nil: true
    delegate :identity, to: :user, allow_nil: true
  
    resets { Time.zone = nil }
  
    def person=(person)
      super
  
      self.account = person.try(:account)
      Time.zone = person.try(:time_zone)
    end
  end
  

  • module SetCurrentRequestDetails

    module SetCurrentRequestDetails
      extend ActiveSupport::Concern
    
      included do
        before_action do
          Current.request_id = request.uuid
          Current.user_agent = request.user_agent
          Current.ip_address = request.ip
        end
      end
    end
    

-- from On Writing Software Well: Using globals when the price is right - YouTube

I was watching DHH's On Writing Software Well screencasts series¹, where he explained the trade offs they've made in the Basecamp codebase.

And this idea of using a class Current to wrap all the global variables really hit me and made me realize that globals don't need to be just variables like redis_client or something like that.

Wrapping these variables in a cohesive class is really a great idea and I really like it. If you are also interested, you can check out the CurrentAttributes class² which supports this style of programming in Rails.