Version Accept headers

api_constraints.rb

class ApiConstraints
  def initialize(options)
    @version = options[:version]
    @default = options[:default]
  end

  def matches?(req)
    @default || req.headers['Accept'].include?("application/vnd.betterbills.v#{@version}")
  end
end

routes.rb

ApiService::Application.routes.draw do
  namespace :person_service, defaults: {format: 'json'} do
    scope module: :v1, constraints: ApiConstraints.new(version: 1) do
      get '/people', to: 'people#index'
    end
  end
end