added err checking

src/routes/authentication.js

@@ -138,6 +138,9 @@
 				app.post('/login', function(req, res, next) {
 					if (req.body.username && utils.isEmailValid(req.body.username)) {
 						user.getUsernameByEmail(req.body.username, function(err, username) {
+							if (err) {
+								return next(err);
+							}
 							req.body.username = username ? username : req.body.username;
 							login(req, res, next);
 						});

src/user.js

@@ -414,6 +414,9 @@ var bcrypt = require('bcryptjs'),
 
 	User.getUsernameByEmail = function(email, callback) {
 		db.getObjectField('email:uid', email, function(err, uid) {
+			if (err) {
+				return callback(err);
+			}
 			User.getUserField(uid, 'username', callback);
 		});
 	};