searching using active_record scope

[jana4u]

Added ability to use active record scope for search. It enables using complex queries (use OR, JOIN other tables etc.) in search.

Example usage:

In model just add scope with lamba and one parameter. In this example it is called :autocomplete_by_names:

class User < ActiveRecord::Base
  scope :autocomplete_by_names, lambda { |query|
    select("users.contact_name, users.business_name").where("(users.contact_name LIKE :query OR users.business_name LIKE :query)", :query => query)
  }

  def name_with_id
    "#{business_name.blank? ? contact_name : business_name} (#{id})"
  end
end

In controller in autocomplete call use just :id (if you don't want any other column to be selected from database or if you use select in your scope) and add new option :search_scope and specify the name of your scope :autocomplete_by_names:

class UsersController < ApplicationController
  autocomplete :user, :id, :full => true, :display_value => :name_with_id, :search_scope => :autocomplete_by_names
end

All other autocomplete options work with this.

[marzapower]

Thumbs up for this pull request!

[manusajith]

@jana4u I think there is already an option to pass scopes, Details here

[jana4u]

@manusajith Yes, but you can use only scopes without parameters - for example:

scope :admin, where(:admin => true)

There is no way to pass search query to those scopes. You can restrict or reorder results using current :scopes option, but you can't change the way how results are found.

[manusajith]

@jana4u got it. There are a few other PR too addressing the issue to pass parameters to the scope.
Will check all and will merge the best one.
Thanks for your PR.