Fixed course status update error and changed poll interval to 15 mins

js/background.js

@@ -196,12 +196,14 @@ function updateTabs() {
 	});
 }
 
-setInterval(updateStatus, 2000);
+const UPDATE_INTERVAL = 1000 * 60 * 15 // 15 mins
+setInterval(updateStatus, UPDATE_INTERVAL);
 
 function updateStatus() {
 	chrome.storage.sync.get('savedCourses', function (data) {
 		var courses = data.savedCourses;
 		for (let i = 0; i < courses.length; i++) {
+			try {
 				let c = courses[i];
 				var xhr = new XMLHttpRequest();
 				xhr.open("GET", c.link, false);
@@ -216,10 +218,13 @@ function updateStatus() {
 				}
 				c.registerlink = registerlink;
 				c.status = newstatus;
+			} catch (e) {
+				console.log('Not logged into UT Coursebook. Could not update class statuses.');
+			}
 		}
 		chrome.storage.sync.set({
 			savedCourses: courses
 		});
-		console.log("updated status' and registerlinks");
+		// console.log("updated status' and registerlinks");
 	});
 }