updated_concurrency.js

// if logic to prevent experiment from running on itself in the editor.
if (window.location.search.match(/\d/g).join("") !== 5450482367) {
	(function() {
		'use strict';
		var experiment_id = window.location.search.match(/\d/g).join("");
		var current_timestamp;
		var next_timestamp;
		var _$;

		// Wait for jQuery to be enabled on the page.
		window.jQueryEnabledInterval = setInterval(function() {
		  if (_$.fn.jquery === "1.7.2") {
				_$ = window.$;
		  	findInitialTimeStamps();
		  	checkForInternalSave();
		    clearInterval(window.jQueryEnabledInterval);
		  }
		}, 50);

		// Retrieve initial timestamps.
		function findInitialTimeStamps() {
			_$.get("https://app.optimizely.com/api/v1/experiments/" + experiment_id, function(response) {
				current_timestamp = new Date(response.last_modified);
				next_timestamp = new Date(response.last_modified);
			});
			recursiveCheck($);
		}

		// Use ajaxComplete to check for internal saves and update timestamp accordingly.
		function checkForInternalSave() {
			_$(document).ajaxComplete(function(event, response, settings) {
				// if any of these endpoints are pinged, then we need to update the timestamp since it's an internal save.
				if (settings.url === "/experiment/save") {
					current_timestamp = JSON.parse(response.responseText).last_modified;
					next_timestamp = JSON.parse(response.responseText).last_modified;
					// Events captured: Start, Pause, Goals and Audiences are loaded asynchronously and are much less prone to concurrency issues.
				} else if (settings.url === "/tool/experiment/pause" || settings.url === "/tool/experiment/start") {
					_$.get("https://app.optimizely.com/api/v1/experiments/" + experiment_id, function(response) {
						current_timestamp = new Date(response.last_modified);
						next_timestamp = new Date(response.last_modified);
					});
				}
			});
		}

		function recursiveCheck() {
			window.checkTimestampInterval = setInterval(function() {
				_$.get("https://app.optimizely.com/api/v1/experiments/" + experiment_id, function(response) {
					next_timestamp = new Date(response.last_modified);
					if (current_timestamp < next_timestamp) {
						$('#last-saved-container').html("WARNING! Saving might overwrite someone else's work since this experiment was saved recently!<br>Copy your work and refresh the page.");
						$('#last-saved-container').removeClass('muted');
						$('#last-saved-container').attr("style", "color: #de5959; !important");
						$('#last-saved-container').css({"position":"relative", "top":-2});
						$('.lego-button-group:eq(1)').css({"position":"relative", "top":-4});
						clearInterval(window.checkTimestampInterval);
					}
				});
			}, 3000);
		}

	})();
}