Authenticate Active Admin + Sidekiq w/ OmniAuth (Google)

oauth_controller.rb

class Admin::OauthController < ApplicationController
  def self.authenticated?(request)
    session = request.session
    session[:email].present? && session[:authenticated_at].present? && (Time.at(session[:authenticated_at]) + 24.hours).future?
  end

  def self.current_user(request)
    session = request.session
    OpenStruct.new(email: session[:email],
                   name: session[:name],
                   first_name: session[:first_name],
                   last_name: session[:last_name],
                   image: session[:image])
  end

  def authenticate
    session[:return_path] = request.fullpath
    redirect_to '/auth/google_oauth2'
  end

  def google
    auth = request.env['omniauth.auth']
    if auth.dig('extra', 'id_info', 'hd') == 'maven-labs.com' && auth.dig('extra', 'id_info', 'email_verified')
      session[:uid] = auth.dig('uid')
      session.merge!(auth.dig('info'))
      session[:authenticated_at] = auth.dig('extra', 'id_info', 'iat')

      redirect_to session.delete(:return_path) || admin_root_path
    else
      logout
    end
  end

  def logout
    session.clear
    redirect_to 'https://sellwithami.com'
  end
end

omniauth.rb

Rails.application.config.middleware.use OmniAuth::Builder do
  provider :google_oauth2, ENV.fetch('GOOGLE_KEY'), ENV.fetch('GOOGLE_SECRET'),
           scope: 'email, profile', hd: REQUIRED_GOOGLE_DOMAIN
end

routes.rb

require 'sidekiq/web'

Rails.application.routes.draw do
  get 'auth/google_oauth2/callback', to: 'admin/oauth#google'
  get 'auth/logout',                 to: 'admin/oauth#logout'

  constraints(Admin::OauthController.method(:authenticated?)) do
    ActiveAdmin.routes(self)
    mount Sidekiq::Web => '/admin/sidekiq', as: 'sidekiq'
  end

  get '/admin',         to: 'admin/oauth#authenticate'
  get '/admin/*path',   to: 'admin/oauth#authenticate'
end