router.post("/", (req, res, next) => {
  User.findOne({ email: req.body.email })
    .exec()
    .then(user => {
      if (user) {
        res.json({ message: "This email is already registered." });
        next();
      } else {
        return bcrypt
          .genSalt(10)
          .then(salt => bcrypt.hash(req.body.password, salt))
          .then(hash => {
            var admin = req.body.isAdmin === "true" ? true : false;
            var user = new User({
              name: req.body.first_name + " " + req.body.last_name,
              email: req.body.email,
              password: hash,
              isAdmin: admin
            });
            return user.save();
          })
          .then(user => {
            res.json(user);
            next();
          });
      }
    })
    .catch(err => console.error("ERROR", err.message));
});