assistant-storefront/app/policies/category_policy.rb

class CategoryPolicy < ApplicationPolicy
  def index?
    @account.users.include?(@user)
  end

  def update?
    @account_user.administrator?
  end

  def show?
    @account_user.administrator?
  end

  def edit?
    @account_user.administrator?
  end

  def create?
    @account_user.administrator?
  end

  def destroy?
    @account_user.administrator?
  end
end

CategoryPolicy.prepend_mod_with('CategoryPolicy')