helps with passing the request forgery protection token back to rails when using ajax with jQuery

application.html.erb

In all layout files (ex. views/layouts/application.html.erb)

<%= javascript_tag "var AUTH_TOKEN = #{form_authenticity_token.inspect};" if protect_against_forgery? -%>

application.js

jQuery(document).ready(function(){

	// Add the authenticity_token with the parameters submitted via ajax
	$(document).ajaxSend(function(event, request, settings) {
	    if ( settings.type == 'post' ) {
	        settings.data = (settings.data ? settings.data + "&" : "")
	            + "authenticity_token=" + encodeURIComponent( AUTH_TOKEN );
			request.setRequestHeader("Content-Type", "application/x-www-form-urlencoded");

	    }
	});
});