Ideas for Datable v0.3

gistfile1.rb

# ./config/initializers/datatable.rb
Datatable::Base.configure do |config|
  config.jquery_ui = true
  config.table_tools = true
  config.sDom = '<"H"lrf>t<"F"ip>'
  config.iDisplayLength = 25
  config.oLanguage =  { 'sProcessing' => "<img alt='Spinner' src='/images/loader.gif'/>", 'sInfoFiltered' => '' }
end



# ./app/datatables/orders_index.rb
class OrdersIndex < DataTable::Base

  relation Order.join(:customer).where("orders.status like 'open'")

  column "orders.order_number" do                         # the first parameter is the 'table.column' name.  Behind the scenes  datatable will
    link_to "{{1}}", order_path("{{3}}")                  # use that parameter to automatically add a select to the relation. This eliminates 
  end                                                     # having to specificy the 'where' or the 'count' separately.  Also notice that the
  column "customers.name"                                 # column method takes a block or option hash.
  column "orders.id", :bVisible => false                   

  option :aaSorting, [[1, 'ASC'], [2,'ASC']]              # per datatable options (default sorting shown)
end



# ./app/datatables/orders_index.rb
class OrdersIndex < DataTable::Base
  # A more complex example using Arel directly.
  
  orders = Order.arel_table
  items = Items.arel_table
  customers = Customer.arel_table

  relation orders.
             join(items).on(items[:order_id].eq(orders[:id])).
             join(customers).on(orders[:customer_id].eq(customers[:id])).
             where(orders[:status].matches('open')).
             group(items[:order_id])

  column orders[:order_number], :link_to => link_to("{{1}}","{{4}}")              # still trying to come up with better ways to do the 
  column customers[:name]                                                         # variable substituion.  No good ideas yet.  I don't like
  column items[:amount].sum                                                       # that you have to know the column indexes
  column orders[:id], :bVisible => false
end



# Simple controller example.  
class OrdersController < ApplicationController
  respond_to :json, :html
  def index
    @data = OrderIndex.query(params)                     # @data is still just an array of rows like it is today
    respond_to do |format|                               
      format.html 
      format.json {render :json => @data}
    end
  end
end



# Example of per request modifications to the query.  Use the 'relation' method you get the relation
# and then you can use any ActiveRelation calls; where, group, having, etc..
class OrdersController < ApplicationController
  respond_to :json, :html
  def index
    orders = Orders.arel_table
    @data = OrderIndex.relation.where("orders.customer_id = #{current_user.id}").query(params)
    authorize! :read, @orders
    respond_to do |format|
      format.html 
      format.json {render :json => @data}
    end
  end
end



# You can also use Arel directly with the relation like you'd expect
class OrdersController < ApplicationController
  respond_to :json, :html
  def index
    orders_table = Orders.arel_table
    @data = OrderIndex.where(orders_table[:user_id].eq(current_user.id)).query(params)
    respond_to do |format|
      format.html 
      format.json {render :json => @data}
    end
  end
end



# In the view we pass the class and the query result to the helper method
<%= datatable OrdersIndex, @orders %>