从 nodemailer 和 sendgrid 获取空错误

Question

我正在尝试使用 nodemailer 和 SendGrid 实现密码重置。代码一直运行到它捕获空错误而不是发送电子邮件的最后一部分。我不知道该怎么办。

这是我的代码

//posting the account email reset
router.post('/password_reset', function(req, res, next) {
  async.waterfall([
    function(done) {
      crypto.randomBytes(20, function(err, buf) {
        var token = buf.toString('hex');
        done(err, token);
      });
    },
    function(token, done) {
      User.findOne({ email: req.body.email }, function(err, user) {
        if (!user) {
          req.flash('error', 'No account with that email address exists.');
          return res.redirect('/password_reset');
        }

        user.resetPasswordToken = token;
        user.resetPasswordExpires = Date.now() + 3600000; // 1 hour

        user.save(function(err) {
          done(err, token, user);
        });
      });
    },
    function(token, user, done) {
      var smtpTransport = nodemailer.createTransport({
        service: 'SendGrid',
        auth: {
          user: 'apikey',
          pass: 'xxx'
        }
      });
      var mailOptions = {
        to: user.email,
        from: 'xxx@gmail.com',
        subject: 'Node.js Password Reset',
        text: 'You are receiving this because you (or someone else) have requested the reset of the password for your account.\n\n' +
          'Please click on the following link, or paste this into your browser to complete the process:\n\n' +
          'http://' + req.headers.host + '/reset/' + token + '\n\n' +
          'If you did not request this, please ignore this email and your password will remain unchanged.\n'
      };
      smtpTransport.sendMail(mailOptions, function(err) {
        req.flash('info', 'An e-mail has been sent to ' + user.email + ' with further instructions.');
        done(err, 'done');
      });
    }
  ], function(err) {
    if (err) return next(err);
    res.redirect('/password_reset');
      console.log(err)
      
  });
});