Mailboxer with two user models

I use Devise for user authentication and create to models, student and teacher. Now, I want to use mailboxer. With mailboxer, we just need to add the acts_as_messageable to both models. However, I'm not quite sure how to setup the controller. Here is my current controller:

class ConversationsController < ApplicationController
  before_action :authenticate_student!
  before_action :authenticate_teacher!
  before_action :get_mailbox

  def index
    @conversations = @mailbox.inbox.paginate(page: params[:page], per_page: 10)
  end

  private

  def get_mailbox
    @mailbox = current_student.mailbox || current_teacher.mailbox
  end
end

Is there any way to make devise groupped both student and teacher models into one scope, like tie them up so we can just call "user" to get both models? Any other solution is welcome.

If you have two Devise models, it would be handy to define a custom current_user method:

# in application_controller.rb
def current_user
  if current_student
     current_student
   else
    current_teacher
  end   
end
helper_method :current_user

As a side note, I would advise you to have a single User model and roles with Rolify + Pundit for authorization. It's better to let Devise at its authentication job, and you can create other models for user-type specific information (i.e a student_profile.rb). That would make your code DRYer and save you a lot of headache.