Ruby and Js codes adapted from my apps

conversation.rb

class Conversation < ActiveRecord::Base
  belongs_to :sender, :foreign_key => :sender_id, class_name: 'User'
  belongs_to :recipient, :foreign_key => :recipient_id, class_name: 'User'
 
  has_many :messages, dependent: :destroy
 
  validates_uniqueness_of :sender_id, :scope => :recipient_id
 
  scope :involving, -> (user) do
    where("conversations.sender_id =? OR conversations.recipient_id =?",user.id,user.id)
  end
 
  scope :between, -> (sender_id,recipient_id) do
    where("(conversations.sender_id = ? AND conversations.recipient_id =?) OR (conversations.sender_id = ? AND conversations.recipient_id =?)", sender_id,recipient_id, recipient_id, sender_id)
  end
end

sort.js

var ready, set_positions;
 
set_positions = function(){
    // loop through and give each task a data-pos
    // attribute that holds its position in the DOM
    $('.panel.panel-default').each(function(i){
        $(this).attr("data-pos",i+1);
    });
}
 
ready = function(){
 
    // call set_positions function
    set_positions();
 
    $('.sortable').sortable();
 
    // after the order changes
    $('.sortable').sortable().bind('sortupdate', function(e, ui) {
        // array to store new order
        updated_order = []
        // set the updated positions
        set_positions();
 
        // populate the updated_order array with the new task positions
        $('.panel.panel-default').each(function(i){
            updated_order.push({ id: $(this).data("id"), position: i+1 });
        });
 
        // send the updated order via ajax
        $.ajax({
            type: "PUT",
            url: '/tasks/sort',
            data: { order: updated_order }
        });
    });
}
 
$(document).ready(ready);
/**
 * if using turbolinks
 */
$(document).on('page:load', ready);