Add a 'private' attribute to tags to allow for admin / mod specific tags

Private tags would allow admins to create tags that only admins could
use, and that regular users could not filter. The best example use case
for this is an 'announements' tag for site announements that all users
should see.

app/models/tag.rb

@@ -1,10 +1,19 @@
 class Tag < ActiveRecord::Base
   attr_accessor :filtered_count
 
-  def self.all_with_filtered_counts
+  # Scope to determine what tags a user can see
+  scope :accessible_to, ->(user) do
+    if user.is_admin?
+      all
+    else
+      where(:private => false)
+    end
+  end
+
+  def self.all_with_filtered_counts(user)
     counts = TagFilter.count(:group => "tag_id")
 
-    Tag.order(:tag).all.map{|t|
+    Tag.order(:tag).accessible_to(user).map{|t|
       t.filtered_count = counts[t.id].to_i
       t
     }

app/views/filters/index.html.erb

@@ -15,7 +15,7 @@
       <th width="15%">Tag</th>
       <th width="78%">Description</th>
     </tr>
-    <% Tag.all(:order => :tag).each do |tag| %>
+    <% Tag.order(:tag).accessible_to(@user).each do |tag| %>
       <tr>
         <td><input type="checkbox" name="tag_<%= tag.tag %>" value=1
           <%= @filtered_tags.map{|ft| ft.tag_id }.include?(tag.id) ?

app/views/stories/_form.html.erb

@@ -24,7 +24,7 @@
 	<%= f.label :tags_a, "Tags:", :class => "required",
     :style => "line-height: 2.3em;" %>
   <%= f.select "tags_a", options_for_select(
-    Tag.all_with_filtered_counts.map{|t|
+    Tag.all_with_filtered_counts(@user).map{|t|
     [ "#{t.tag} - #{t.description}", t.tag, { "data-html" => raw("<strong>") +
       t.tag + raw("</strong> - ") + t.description.to_s +
       (t.filtered_count == 0 ? "" :

db/migrate/20120919195401_private_tags.rb

@@ -0,0 +1,15 @@
+class PrivateTags < ActiveRecord::Migration
+  def up
+    add_column :tags, :private, :boolean, :default => false
+
+    # All existing tags should be public by default
+    Tag.all.each do |t|
+      t.private = false
+      t.save
+    end
+  end
+
+  def down
+    remove_column :tags, :private
+  end
+end

db/schema.rb

@@ -11,7 +11,7 @@
 #
 # It's strongly recommended to check this file into your version control system.
 
-ActiveRecord::Schema.define(:version => 20120918152116) do
+ActiveRecord::Schema.define(:version => 20120919195401) do
 
   create_table "comments", :force => true do |t|
     t.datetime "created_at",                                                                          :null => false
@@ -115,6 +115,7 @@ ActiveRecord::Schema.define(:version => 20120918152116) do
     t.string  "tag",                 :limit => 25,  :default => "",    :null => false
     t.string  "description",         :limit => 100
     t.boolean "filtered_by_default",                :default => false
+    t.boolean "private",                            :default => false
   end
 
   add_index "tags", ["tag"], :name => "tag", :unique => true