17 - adding taggability with a database mixin.rb

O Reilly Ruby Cookbook source code

require 'cookbook_dbconnect'
require 'og'
require 'glue/taggable'

class BlogPost
  is Taggable
  property :title, :content, String
end
og_connect

# Now we can play around with tags.
post = BlogPost.new
post.title = 'Some more facts about video games'
post.tag(['editorial', 'games'])

BlogPost.find_with_tags('games').each { |puts| puts post.title }
# Some more facts about video games

Tag.find_by_name('editorial').blog_posts.each { |post| puts post.title }
# Some more facts about video games
#---
DROP TABLE IF EXISTS tags;
CREATE TABLE tags (
  id INT(11) NOT NULL AUTO_INCREMENT,
  name VARCHAR(32),
  PRIMARY KEY (id)
) ENGINE=InnoDB;

DROP TABLE IF EXISTS tags_blog_posts;
CREATE TABLE tags_blog_posts (
   tag_id INT(11),
   blog_post_id INT(11)
) ENGINE=InnoDB;
#---
require 'cookbook_dbconnect'
require 'taggable'
activerecord_connect

class Tag < ActiveRecord::Base
end

class BlogPost < ActiveRecord::Base
  acts_as_taggable
end

# Now we can play around with tags.
post = BlogPost.create(:title => 'Some more facts about inflation.')
post.tag(['editorial', 'economics'])

BlogPost.find_tagged_with(:any=>'editorial').each { |post| puts post.title }
# Some more facts about inflation.
#---
DROP TABLE IF EXISTS tags_blog_posts;
CREATE TABLE tags_blog_posts (
   tag_id INT(11),
   blog_post_id INT(11),
   created_by_id INT(11)
) ENGINE=InnoDB;

#---
require 'cookbook_dbconnect'
require 'taggable'
activerecord_connect

class Tag < ActiveRecord::Base
end

class Person < ActiveRecord::Base
end
#---
# ActiveRecord will automatically define the TagBlogPost class when
# we reference it.
class BlogPost < ActiveRecord::Base
  acts_as_taggable :join_class_name => 'TagBlogPost'
end
#---
# Specify that a TagBlogPost is associated with a specific user.
class TagBlogPost
  belongs_to :created_by, :class_name => 'Person', 
             :foreign_key => 'created_by_id'
end
#---
post = BlogPost.create(:title => 'My visit to the steel mill.')
alice = Person.create(:name=>"Alice")
post.tag(['travelogue', 'metal', 'interesting'], 
         :attributes => { :created_by => alice })

alices_interests = BlogPost.find_tagged_with(:all => 'interesting', 
       :condition => "tags_people.created_by_id = #{alice.id}")
alices_interests.each { |article| puts article.title }
# My visit to the steel mill.
#---