price-point-api/app/controllers/application_controller.rb

class ApplicationController < ActionController::API
  include Renderable

  before_action :authenticate!

  rescue_from Unauthorized do
    render_error("Unauthorized", :unauthorized)
  end

  private
  def authenticate!
    token = request.headers["Authorization"]&.split(" ")&.last
    @current_session = Session.find_by(token: token)
    raise Unauthorized unless @current_session

    @current_user = @current_session.user
  end

  def current_user
    @current_user
  end

  def current_session
    @current_session
  end
end