Your First Admin Resource: AdminUser

This guide assumes you’ve used the default AdminUser model, with Devise.

Start by logging into your admin section at http://localhost:3000/admin. The migration created a user with the credentials [email protected] / password.

Your first step is to generate the section to manage your admin users:

rails generate active_admin:resource AdminUser

This will create an empty file:

#app/admin/admin_users.rb
ActiveAdmin.register AdminUser do
end

Index

Loading http://localhost:3000/admin/admin_users/ will show a pretty noisy default index page. So our first step will be to clean it up:

#app/admin/admin_users.rb
ActiveAdmin.register AdminUser do
  index do
    column :email
    column :current_sign_in_at
    column :last_sign_in_at
    column :sign_in_count
    default_actions
  end
end

Check out the documentation for index pages to tweak it some more: http://activeadmin.info/documentation.html#Customizing%20the%20Index%20Page

Form

Now comes the time to create your first real administrator. The “New Admin User” button also leads to a page with too many fields. Let’s simplify it as well:

#app/admin/admin_users.rb
ActiveAdmin.register AdminUser do
  #...
  form do |f|
    f.inputs "Admin Details" do
      f.input :email
    end
    f.buttons
  end
end

The current form doesn’t let you create a valid admin user instance because it doesn’t let you specify a password. Instead of forcing administrators to set a dummy password on new admin accounts, and then send an email to the person, we’ll let Devise do it’s thing.

This approach requires that your admin model is devise ... :recoverable (this is the case by default). We’ll make the password for new admin users optional for when creating a new user and we’ll send the password recovery email to let the new user set his own password:

#app/models/admin_user.rb
  after_create { |admin| admin.send_reset_password_instructions }
  def password_required?
    new_record? ? false : super
  end

So when you create a new admin, an email is automatically sent to your new admin. Until the person clicks the link to set his password, it’s impossible to log into the account.

Customizing the show form is left to your discretion :-)

You should add this to your AdminUser Model too if you don’t want to take the risk of deleting the last admin:

#app/models/admin_user.rb
before_destroy :raise_if_last
def raise_if_last
  if AdminUser.count < 2
    raise "Can't delete last admin user"
  end
end