How to put app into maintenance mode but still allow admins/moderatos to login and use the site?

I'd like to put my app into maintenance mode but still have admins / moderator开发者_如何学Pythons be able to log in and use the site.

Two reasons:

1. I'm making some changes within the app that are best applied using the in-app interface rather than the console.

2. Moderators don't have access to the console, but can definitely help with the maintenance tasks we have ahead of us.

How would you recommend this be done? I have been experimenting with setting an environment variable ADMIN_MODE and changing all the permissions when it is true, but that seems pretty cludgy and slow.

I'm using CanCan and Devise, for what it's worth, but I'm definitely open to any suggestions.

This would probably be a fairly simple solution:

class ApplicationController < ActionController::Base
  before_filter :check_admin_mode

  protected

  def check_admin_mode
    if ENV['ADMIN_MODE'] && controller_name != 'sessions' && !current_user.admin?
      redirect_to '/maintenance.html'
    end
  end
end

I think aNoble's solution is fine, another way might be to get your webserver to do this, I use Capistrano's cap deploy:web:disable task and then mod_rewrite to conditionally redirect either to the maintenance page or allow specific users through by IP address, but you may be able to write your own conditions.

# Redirect to system maintenance if exists - used by cap deploy:web:disable
RewriteCond %{REQUEST_URI} !\.(css|jpg|png|gif)$
RewriteCond %{DOCUMENT_ROOT}/system/maintenance.php -f 
# Allow me through
RewriteCond %{REMOTE_ADDR} "!^XXX\.XXX\.XXX\.XXX"
RewriteCond %{SCRIPT_FILENAME} !maintenance.php [NC]
RewriteRule ^.*$ /system/maintenance.php [L]

I did something similar which might be useful to people who are still interested

class ApplicationController < ActionController::Base
  before_filter :check_maintenance_mode

  protected

  def check_maintenance_mode

    temp_var = self.class.to_s.split("::").first

    return if temp_var.casecmp("admin") == 0 || temp_var.casecmp("activeadmin") == 0

    if site_setting.maintenance_mode
      redirect_to maintenance_path unless request.fullpath.include?(maintenance_path)
    else
      redirect_to root_path if request.fullpath.include?(maintenance_path)
    end

  end

end

First, what I did is to split the class name to get the module name or controller name that I am accessing which I will exit from the method if I am entering the admin zone. You do not want the maintenance page to affect the admin module

Second, I check for maintenance mode and if its true, I will redirect the users to maintenance page UNLESS they are already on the page itself. If maintenance mode is not on, users will be redirected back to root_path

Fyi, I am using activeadmin as my admin page. Hope this helps someone in 2015.