[LoKeR]

var router = require('express').Router();

router.post('/singin', function (req, res, next) {
    var phone      = req.body.phone;
    var password   = req.body.password;

    User.singin(phone, password, function (err, user) {
        if(err) {
            return next(err);

            console.log(err);
        }

        console.log(user);

        req.session.user = user._id;
        res.send({});
    });
});

module.exports = router;

seaman, так понятнее?