NOTE: THIS GEM IS RAILS 2.X COMPATIBLE ONLY.

I have no intention to port it to 3.x, since this kind of thing is much easier in the newest ActiveRecord, anyway.

Ismael Celis

http://github.com/ismasan/sluggable_finder

This gem is originally based on http://github.com/smtlaissezfaire/acts_as_sluggable/tree/master/lib%2Facts_as_slugable.rb

This is a variation of acts_as_sluggable, permalink_fu and acts_as_permalink. This plugin allows models to generate a unique "slug" (url-enabled name) from any regular attribute. Sluggable models can have a scope parameter so slugs are unique relative to a parent model.

The plugin intercepts ActiveRecord::Base.find to look into the slug field if passed a single string as an argument. It works as normal if you pass an integer or more finder parameters.

The plugin modifies to_param so it's transparent to link_to and url_for view helpers

Slugs are created when a model is created. Subsequent changes to the source field will not modify the slug unless you specifically change the value of the slug field. This is because permalinks should never change.

Complete specs. To test, make sure you create an empty SQLite database.

Run the following to load the test schema:

rake db:create

Now you can run the tests

rake spec

class Category < ActiveRecord::Base
	has_many :posts
	sluggable_finder :title #slugifies the :title field into the :slug field
end

class Post < ActiveRecord::Base
	belongs_to :category
	has_many :comments
	sluggable_finder :title, :scope => :category_id #Post slugs are unique to the parent category
end

class Comment < ActiveRecord::Base
	belongs_to :post
	sluggable_finder :get_slug, :to => :permalink #creates slug from custom attribute and stores it in "permalink" field

	def get_slug #we define the custom attribute
		"#{post.id}-#{Time.now}"
	end
end

# Provide a list or reserved slugs you don't want available as permalinks
#
sluggable_finder :title, :reserved_slugs => %w(admin settings users)

By default, Integer-like permalinks will fallback to normal ActiveRecord IDs, so

Comment.find '1234'

... Will look in the ID column instead of the slug column. If you're using Integer-like strings in your slug column, you can ignore integer ID lookup completely with:

class Comment < ActiveRecord::Base
  sluggable_finder :title, :allow_integer_ids => false
end

Slug uniqueness will be checked accross all classes in STI models. If you want to scope by sub-class, use :ignore_sti

class Comment < SomeParentClass
  sluggable_finder :title, :ignore_sti => true
end

You can pass an optional block to pre-process the slug before saving

class Comment < SomeParentClass
  sluggable_finder :title do |slug_candidate|
    "comment-#{slug_candidate}"
  end
end

You can do Model.find(slug) just how you would with a single numerical ID. It will also raise a RecordNotFound exception so you can handle that in your application controller. The idea is that you keep your controller actions clean and handle Not Found errors elsewhere. You can still use Model.find the regular way.

class PostsController < ApplicationController
    # params[:id] is a string, URL-encoded slug
	def show
		@post = Post.find( params[:id] ) #raises ActiveRecord::RecordNotFound if not found
	end  
end

In merb it would be nice to raise a NotFound exception instead of ActiveRecord's RecordNotFoundm so we don't need to clutter our controller with exception-handling code and we let the framework handle them.

SluggableFinder.not_found_exception = Merb::ControllerExceptions::NotFound

You can configure this to raise any exception you want.

class CustomException < StandardError; end

SluggableFinder.not_found_exception = CustomException

Link generation remains the same, because the plugin overwrites your model's to_param method

<%= link_to h(@post.title), @post %> # => <a href="/posts/hello-world">Hello world</a>

ActiveRecord, ActiveSupport

You can install or clone the repo from Github, but the recommended way for normal usage is to install the latest stable version from Gemcutter.org:

If you haven't yet, add gemcutter.org to your gem sources (you only need to do that once):

gem sources -a http://gemcutter.org

Now you can install the normal way:

sudo gem install sluggable_finder

Then, in your Rails app's environment:

config.gem "sluggable_finder"

If you wan to unpack the gem to you app's "vendor" directory:

rake gems:unpack

*Refactor. It works but I hate the code. Find a way to override ActiveRecord.find more cleanly. Maybe Rails 3?

(The MIT License)

Copyright (c) 2008 Ismael Celis

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the 'Software'), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED 'AS IS', WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.