In Rails, how can I share a private method to nested controllers?

Question

I have a resource of Player that has various nested resources, such as: Measurable and Workout.

I have a variable that is used int he Player's header on their pages and it has a variable I need to be set whether I'm accessing an action from the Player_Controller or from one of the other nested resources controllers. How can I dry up my code to add that variable somewhere so that I don't have to include the same like of code in every controller... as shown below:

PlayerController

class PlayersController < ApplicationController
   before_action :set_measurable_summary

   #...

   private
     def set_measurable_summary
       @measurable_summary = @player.measurable_summary
     end
end

WorkoutController

class Players::WorkoutsController < ApplicationController
   before_action :set_measurable_summary

   #...

   private
     def set_measurable_summary
       @measurable_summary = @player.measurable_summary
     end
end

Answer 1

This can be easily done with a concern:

# app/controllers/concerns/measurable_summary.rb

module MeasurableSummary
  extend ActiveSupport::Concern

  included do
    before_action :set_measurable_summary
  end

  private

  def set_measurable_summary
    @measurable_summary = @player.measurable_summary
  end
end

Then include it into your controllers:

class PlayersController < ApplicationController
  include MeasurableSummary
  ...
end

class Players::WorkoutsController < ApplicationController
  include MeasurableSummary
  ...
end

Answer 2

You can move that method to ApplicationController

class ApplicationController < ActionController::Base

  private

  def set_measurable_summary
    @measurable_summary = @player.measurable_summary
  end
end

Answer 3

You can use extend controller to get parent private method. Please do this:

class Players::WorkoutsController < PlayersController
end