Rocket Tag

Clean, modern and maintainable, context aware tagging library for rails 3.1 +

Installation

In your gemfile

gem "rocket_tag"

Then at the command line

bundle install

Create the migration at the command line

rails generate rocket_tag:migration
rake db:migrate
rake db:test:prepare

Usage

class TaggableModel < ActiveRecord::Base
	attr_taggable :skills, :habits
end	

item = TaggableModel.create

item.skills = ["kiting", "surfing", "coding"]
item.habits = ["forking", "talking"]

Match any tag across any contexts

TaggableModel.tagged_with ["forking", "kiting"]  

Match all tags across any contexts

TaggableModel.tagged_with ["forking", "kiting"], :all => true

Match any tag on a specific context

TaggableModel.tagged_with ["math", "kiting"], :on => "skills"

Match all tags on a specific context

TaggableModel.tagged_with ["math", "kiting"], :all => true, :on => "skills"

Match a miniumum number of tags

TaggableModel.tagged_with ["math", "kiting", "coding", "sleeping"], :min => 2, :on => "skills"

Take advantage of the tags_count synthetic column returned with every query

TaggableModel.tagged_with(["math", "kiting", "coding", "sleeping"], :on => "skills").where{tags_count>=2}	

Mix with active relation

TaggableModel.tagged_with(["forking", "kiting"]).where( ["created_at > ?", Time.zone.now.ago(5.hours)])  

Find similar models based on tags on a specific context and return in decending order of 'tags_count'

model.tagged_similar :on => "skills"
model.tagged_similar :on => "habits"

Find similar models based on tags on every context and return in decending order of 'tags_count'. Note that each tag is still scoped according to it's context

model.tagged_similar  

For reference the SQL generated for model.tagged_similar when there are context [:skills, :languages] available is

  SELECT "taggable_models".* FROM   
        (
          SELECT COUNT("taggable_models"."id") AS tags_count, 
                 taggable_models.* 
          FROM   "taggable_models" 
                 INNER JOIN "taggings" 
                   ON "taggings"."taggable_id" = "taggable_models"."id" 
                      AND "taggings"."taggable_type" = 'TaggableModel' 
                 INNER JOIN "tags" 
                   ON "tags"."id" = "taggings"."tag_id" 
          WHERE  "taggable_models"."id" != 2 
                 AND ((   ( "tags"."name" IN ( 'german', 'french' ) AND "taggings"."context" = 'languages' ) 
                       OR ( "tags"."name" IN ( 'a', 'b', 'x' )      AND "taggings"."context" = 'skills' ) 
                     )) 
          GROUP  BY "taggable_models"."id" 
          ORDER  BY tags_count DESC
        ) taggable_models 

Note the aliasing of the inner select to shield the GROUP BY from downstream active relation queries

== Contributing to rocket_tag

• Check out the latest master to make sure the feature hasn't been implemented or the bug hasn't been fixed yet
• Check out the issue tracker to make sure someone already hasn't requested it and/or contributed it
• Fork the project
• Start a feature/bugfix branch
• Commit and push until you are happy with your contribution
• Make sure to add tests for it. This is important so I don't break it in a future version unintentionally.
• Please try not to mess with the Rakefile, version, or history. If you want to have your own version, or is otherwise necessary, that is fine, but please isolate to its own commit so I can cherry-pick around it.

== Copyright

Copyright (c) 2011 Brad Phelan. See LICENSE.txt for further details.

Available for hire for your next ROR project at XTargets: Ruby On Rails Solutions