diff --git a/src/controllers/authentication.js b/src/controllers/authentication.js
index 21b067f58e..dcd9aa371f 100644
--- a/src/controllers/authentication.js
+++ b/src/controllers/authentication.js
@@ -379,7 +379,7 @@ authenticationController.onSuccessfulLogin = async function (req, uid) {
 			}),
 			user.auth.addSession(uid, req.sessionID),
 			user.updateLastOnlineTime(uid),
-			user.updateOnlineUsers(uid),
+			user.onUserOnline(uid, Date.now()),
 			analytics.increment('logins'),
 			db.incrObjectFieldBy('global', 'loginCount', 1),
 		]);
diff --git a/src/socket.io/index.js b/src/socket.io/index.js
index a4a4327005..67a1e4bda0 100644
--- a/src/socket.io/index.js
+++ b/src/socket.io/index.js
@@ -112,48 +112,49 @@ async function onMessage(socket, payload) {
 		return winston.warn('[socket.io] Empty payload');
 	}
 
-	const eventName = payload.data[0];
+	let eventName = payload.data[0];
 	const params = typeof payload.data[1] === 'function' ? {} : payload.data[1];
 	const callback = typeof payload.data[payload.data.length - 1] === 'function' ? payload.data[payload.data.length - 1] : function () {};
 
-	if (!eventName) {
-		return winston.warn('[socket.io] Empty method name');
-	}
-
-	if (typeof eventName !== 'string') {
-		const escapedName = validator.escape(String(eventName));
-		return callback({ message: `[[error:invalid-event, ${escapedName}]]` });
-	}
+	try {
+		if (!eventName) {
+			return winston.warn('[socket.io] Empty method name');
+		}
 
-	const parts = eventName.split('.');
-	const namespace = parts[0];
-	const methodToCall = parts.reduce((prev, cur) => {
-		if (prev !== null && prev[cur] && (!prev.hasOwnProperty || prev.hasOwnProperty(cur))) {
-			return prev[cur];
+		if (typeof eventName !== 'string') {
+			eventName = typeof eventName;
+			const escapedName = validator.escape(eventName);
+			return callback({ message: `[[error:invalid-event, ${escapedName}]]` });
 		}
-		return null;
-	}, Namespaces);
 
-	if (!methodToCall || typeof methodToCall !== 'function') {
-		if (process.env.NODE_ENV === 'development') {
-			winston.warn(`[socket.io] Unrecognized message: ${eventName}`);
+		const parts = eventName.split('.');
+		const namespace = parts[0];
+		const methodToCall = parts.reduce((prev, cur) => {
+			if (prev !== null && prev[cur] && (!prev.hasOwnProperty || prev.hasOwnProperty(cur))) {
+				return prev[cur];
+			}
+			return null;
+		}, Namespaces);
+
+		if (!methodToCall || typeof methodToCall !== 'function') {
+			if (process.env.NODE_ENV === 'development') {
+				winston.warn(`[socket.io] Unrecognized message: ${eventName}`);
+			}
+			const escapedName = validator.escape(String(eventName));
+			return callback({ message: `[[error:invalid-event, ${escapedName}]]` });
 		}
-		const escapedName = validator.escape(String(eventName));
-		return callback({ message: `[[error:invalid-event, ${escapedName}]]` });
-	}
 
-	socket.previousEvents = socket.previousEvents || [];
-	socket.previousEvents.push(eventName);
-	if (socket.previousEvents.length > 20) {
-		socket.previousEvents.shift();
-	}
+		socket.previousEvents = socket.previousEvents || [];
+		socket.previousEvents.push(eventName);
+		if (socket.previousEvents.length > 20) {
+			socket.previousEvents.shift();
+		}
 
-	if (!eventName.startsWith('admin.') && ratelimit.isFlooding(socket)) {
-		winston.warn(`[socket.io] Too many emits! Disconnecting uid : ${socket.uid}. Events : ${socket.previousEvents}`);
-		return socket.disconnect();
-	}
+		if (!eventName.startsWith('admin.') && ratelimit.isFlooding(socket)) {
+			winston.warn(`[socket.io] Too many emits! Disconnecting uid : ${socket.uid}. Events : ${socket.previousEvents}`);
+			return socket.disconnect();
+		}
 
-	try {
 		await checkMaintenance(socket);
 		await validateSession(socket, '[[error:revalidate-failure]]');
 
diff --git a/src/user/online.js b/src/user/online.js
index ffba4c9a94..b7c6b9d45a 100644
--- a/src/user/online.js
+++ b/src/user/online.js
@@ -27,9 +27,13 @@ module.exports = function (User) {
 		if (now - parseInt(userOnlineTime, 10) < 300000) {
 			return;
 		}
-		await db.sortedSetAdd('users:online', now, uid);
+		await User.onUserOnline(uid, now);
 		topics.pushUnreadCount(uid);
-		plugins.hooks.fire('action:user.online', { uid: uid, timestamp: now });
+	};
+
+	User.onUserOnline = async (uid, timestamp) => {
+		await db.sortedSetAdd('users:online', timestamp, uid);
+		plugins.hooks.fire('action:user.online', { uid, timestamp });
 	};
 
 	User.isOnline = async function (uid) {
diff --git a/test/socket.io.js b/test/socket.io.js
index e95eb6527e..726f6f71ad 100644
--- a/test/socket.io.js
+++ b/test/socket.io.js
@@ -110,8 +110,7 @@ describe('socket.io', () => {
 	it('should return error for invalid eventName type', (done) => {
 		const eventName = ['topics.loadMoreTags'];
 		io.emit(eventName, (err) => {
-			const eventAsString = String(eventName);
-			assert.strictEqual(err.message, `[[error:invalid-event, ${eventAsString}]]`);
+			assert.strictEqual(err.message, `[[error:invalid-event, object]]`);
 			done();
 		});
 	});