duration from the extension start time to reaching a valid stop url sent from background to content

extension/js/background.js

 var debug = 1;
-
+var start_time = Date.now();
+var stop_time;
+var duration;
 var urls_to_compare = readTextFile("../data/urls.txt");
 
 /* this code base courtesty of https://stackoverflow.com/questions/14446447/javascript-read-local-text-file#14446538*/
@@ -15,6 +17,13 @@ function readTextFile(file){
 	rawFile.send(null);
 	return(lines);}
 
+// abstracted in case we want to modify how we parse the duration
+function get_duration(){
+	stop_time = Date.now();
+	var local_duration = stop_time - start_time;
+	return local_duration;
+}
+
 function is_a_stop(possible_stop_urls, current_url){
 	if (debug){
 		console.log("URLs to compare");
@@ -37,6 +46,7 @@ chrome.tabs.onUpdated.addListener(function (tabID, changeInfo, tab) {
 		if (debug){ console.log(url);}
 		if (changeInfo.status=='complete'){
 			if (is_a_stop(urls_to_compare, url)){
-				chrome.tabs.sendMessage(tab.id, { action: 'match' });
+				duration = get_duration();
+				chrome.tabs.sendMessage(tab.id, { action: duration });
 				if (debug) {console.log("background found match");}} } 
 });});

extension/js/content.js

 chrome.runtime.onMessage.addListener(function (msg) {
     /* We received a message, let's do as instructed */
-    if (msg.action == 'match') {
-        window.alert('Google!');
-    }
+//    if (msg.action == 'match') {
+        console.log(msg.action);
+//    }
 });