ruby script/plugin install http://svn.viney.net.nz/things/rails/plugins/acts_as_taggable_on_steroids/

=== Prepare database
Generate and apply the migration:

ruby script/generate acts_as_taggable_migration
rake db:migrate

=== Basic tagging
Using the examples from the tests, let's suppose we have users that have many posts and we want those posts to be able to be tagged by the user.

As usual, we add +acts_as_taggable+ to the Post class:

class Post < ActiveRecord::Base
  acts_as_taggable
  
  belongs_to :user
end

We can now use the tagging methods provided by acts_as_taggable, tag_list and tag_list=. Both these methods work like regular attribute accessors.

p = Post.find(:first)
p.tag_list.to_s # ""
p.tag_list = "Funny, Silly"
p.save
p.reload.tag_list.to_s # "Funny, Silly"

You can also add or remove arrays of tags.

p.tag_list.add("Great", "Awful")
p.tag_list.remove("Funny")

=== Finding tagged objects
To retrieve objects tagged with a certain tag, use find_tagged_with.

Post.find_tagged_with('Funny, Silly')

By default, find_tagged_with will find objects that have any of the given tags. To
find only objects that are tagged with all the given tags, use match_all.

Post.find_tagged_with('Funny, Silly', :match_all => true)

=== Tag cloud calculations
To construct tag clouds, the frequency of each tag needs to be calculated. Because we specified +acts_as_taggable+ on the Post class, we can get a calculation of all the tag counts by using Post.tag_counts. But what if we wanted a tag count for an single user's posts? To achieve this we call tag_counts on the association:

User.find(:first).posts.tag_counts

=== Caching

It is useful to cache the list of tags to reduce the number of queries executed. To do this, add a column named cached_tag_list to the model which is being tagged.

class CachePostTagList < ActiveRecord::Migration
  def self.up
    # You should make sure that the column is long enough to hold
    # the full tag list. In some situations the :text type may be more appropriate.
    add_column :posts, :cached_tag_list, :string
  end
end

class Post < ActiveRecord::Base
  acts_as_taggable
  
  # The caching column defaults to cached_tag_list, but can be changed:
  # 
  # set_cached_tag_list_column_name "my_caching_column_name"
end

The details of the caching are handled for you. Just continue to use the tag_list accessor as you normally would. Note that the cached tag list will not be updated if you directly create Tagging objects or manually append to the tags or taggings associations. To update the cached tag list you should call save_cached_tag_list manually.


=== Delimiter
If you want to change the delimiter used to parse and present tags, set TagList.delimiter. For example, to use spaces instead of commas, add the following to config/environment.rb:

TagList.delimiter = " "

There is currently no advanced documentation for this plugin.