Searchtastic makes it possible to filter any collection of ActiveRecord models automatically based on any field, including associated fields not even on the model itself. It's kind of awesome.

In Rails 3, add this to your Gemfile and run the bundle command.

gem 'searchtastic'

Make a model searchable by providing an array of attributes to search on:

class User < ActiveRecord::Base
    attr_accessible :name, :bio
    has_one :club, class_name: Organization
    searchable_by :name, :bio, :'club.name'
end

Searching works anywhere, but normally you'll search from within a controller action:

...
def index
    #@filter == "test"
    @users = User.search(@filter)
    ...
end
...

Note that this works for any ActiveRelation so this will work as well:

...
def index
    #@filter == "pete"
    @users = @foo.users.search(@filter)
    ...
end
...

• Search on combined fields, e.g. first_name + last_name
• Search on all accessible attributes shorthand
• Search on Date Ranges
• Search against has_many :through associations
• Search against HABTM associations

searchtastic is solely Pete Michaud's (me@petermichaud.com) fault, so blame him for everything.

(The MIT License)

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.

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