使用CanCan时如何启用管理员销毁记录？

Question

My current code is just like this.
Only the user who posted can destroy his own records.
But I want to enable admin(user.id=1) to delete all the records.

How can I change this? also view? any smart way?

/models/ability.rb

def initialize(user)
    if user
        can :read, :all 
        can [:create, :destroy], Comment, {:user_id => user.id}
        can [:destroy], Comment, {:commentable_id => user.id, :commentable_type => user.class.name}
        can [:create, :update], Community, {:user_id => user.id}
    else
        can :read, :all 
    end
end

View

<%= link_to 'x', polymorphic_path([@user, comment]),
    :data => { :confirm => 'Do you want to delete?' },  
    :method => :delete, :disable_with => 'Deleting', 
    :remote => true, 
    :class => 'close'
if current_user && current_user.id == comment.user_id || current_user && current_user.id == comment.commentable_id %>

Answer 1

Here is what you need. BTW it is bad idea to use user.id == 1 to check for admin rights, probably better solution is to add boolean admin field to User model. If you don't want to do it, you can replace if user.admin? with if user.id == 1 .

def initialize(user)
  guest_ability
  user_ability(user) if user
  admin_ability if user.admin? # or `if user.id == 1` if you don't want to add `admin` field
end

private

def admin_ability(admin)
  can [:destroy], Comment
end

def user_ability(user)
  can :read, :all 
  can [:create, :destroy], Comment, { :user_id => user.id }
  can [:destroy], Comment, { :commentable_id => user.id, :commentable_type => user.class.name }
  can [:create, :update], Community, { :user_id => user.id }
end

def guest_ability
  can :read, :all
end

In your view:

<% if can? :destroy, comment %>
  <%= link_to 'x', polymorphic_path([@user, comment]),
        :data => { :confirm => 'Do you want to delete?' },  
        :method => :delete, :disable_with => 'Deleting', 
        :remote => true, 
        :class => 'close' %>
<% end %>

Answer 2

In your ability file, you should make a distinction betyween the various roles a user can have, so you should add something like

if user.has_role? :admin
  can :destroy, Comment
end

In your view, instead of "doing al the work yourself", as you're doing now, you should use the can? method, as follows

if can? :destroy, comment

Using can? will use the directions you've described in your ability file. As simple as that!