zammad/app/controllers/application_controller/handles_devices.rb

module ApplicationController::HandlesDevices
  extend ActiveSupport::Concern

  included do
    before_action :user_device_check
  end

  def user_device_check
    return false if !user_device_log(current_user, 'session')
    true
  end

  def user_device_log(user, type)
    switched_from_user_id = ENV['SWITCHED_FROM_USER_ID'] || session[:switched_from_user_id]
    return true if params[:controller] == 'init' # do no device logging on static inital page
    return true if switched_from_user_id
    return true if !user
    return true if !user.permissions?('user_preferences.device')

    time_to_check = true
    user_device_updated_at = session[:user_device_updated_at]
    if ENV['USER_DEVICE_UPDATED_AT']
      user_device_updated_at = Time.zone.parse(ENV['USER_DEVICE_UPDATED_AT'])
    end

    if user_device_updated_at
      # check if entry exists / only if write action
      diff = Time.zone.now - 10.minutes
      method = request.method
      if method == 'GET' || method == 'OPTIONS' || method == 'HEAD'
        diff = Time.zone.now - 30.minutes
      end

      # only update if needed
      if user_device_updated_at > diff
        time_to_check = false
      end
    end

    # if ip has not changed and ttl in still valid
    remote_ip = ENV['TEST_REMOTE_IP'] || request.remote_ip
    return true if time_to_check == false && session[:user_device_remote_ip] == remote_ip
    session[:user_device_remote_ip] = remote_ip

    # for sessions we need the fingperprint
    if type == 'session'
      if !session[:user_device_updated_at] && !params[:fingerprint] && !session[:user_device_fingerprint]
        raise Exceptions::UnprocessableEntity, 'Need fingerprint param!'
      end
      if params[:fingerprint]
        session[:user_device_fingerprint] = params[:fingerprint]
      end
    end

    session[:user_device_updated_at] = Time.zone.now

    # add device if needed
    http_user_agent = ENV['HTTP_USER_AGENT'] || request.env['HTTP_USER_AGENT']
    Delayed::Job.enqueue(
      Observer::UserDeviceLogJob.new(
        http_user_agent,
        remote_ip,
        user.id,
        session[:user_device_fingerprint],
        type,
      )
    )
  end
end