发布JSON发送电子邮件与Nodemailer要么发送邮件，但挂起或抛出一个错误

Question

我的工作MERN应用程序与一个基本的联系形式，使用Nodemailer发送电子邮件。我想从服务器的某种响应，可以显示在前端，如邮件发送或邮件未发送等...

这是我的第一次尝试（来自server.js的代码），基于以下示例：

myRoutes.route('/send-mail').post(async function(req, res) {
  let testAccount = await nodemailer.createTestAccount();

  // create reusable transporter object using the default SMTP transport
  let transporter = nodemailer.createTransport({
      host: 'smtp.ethereal.email',
      port: 587,
      secure: false, // true for 465, false for other ports
      auth: {
          user: testAccount.user, // generated ethereal user
          pass: testAccount.pass // generated ethereal password
      }
  });

  let senderName = req.body.senderName;
  let senderEmail = req.body.senderEmail;
  let subject = req.body.subject;
  let message = req.body.message;
  let toEmail = req.body.toEmail;

  // send mail with defined transport object
  let info = await transporter.sendMail({
      from: `"${senderName}" <${senderEmail}>`, // sender address
      to: toEmail, // receiver address
      subject: subject, // Subject line
      text: message, // plain text body
      html: message
  });

  console.log('Message sent: %s', info.messageId);
  // Message sent: <[e-mail]>

  // Preview only available when sending through an Ethereal account
  console.log('Preview URL: %s', nodemailer.getTestMessageUrl(info));
  // Preview URL: https://ethereal.email/message/WaQKMgKddxQDoou...
});

这是可行的（邮件被发送，预览URL被记录到控制台），但是对服务器的发布请求只是挂起，直到它最终超时。所以，因为我无论如何都需要这样做，从服务器获取响应，这将通知前端的用户，我想我应该在sendMail函数之后添加一个回调。

带回调的代码：

myRoutes.route('/send-mail').post(async function(req, res) {
  let testAccount = await nodemailer.createTestAccount();

  // create reusable transporter object using the default SMTP transport
  let transporter = nodemailer.createTransport({
      host: 'smtp.ethereal.email',
      port: 587,
      secure: false, // true for 465, false for other ports
      auth: {
          user: testAccount.user, // generated ethereal user
          pass: testAccount.pass // generated ethereal password
      }
  });

  let senderName = req.body.senderName;
  let senderEmail = req.body.senderEmail;
  let subject = req.body.subject;
  let message = req.body.message;
  let toEmail = req.body.toEmail;

  // send mail with defined transport object
  let info = await transporter.sendMail({
      from: `"${senderName}" <${senderEmail}>`, // sender address
      to: toEmail, // receiver address
      subject: subject, // Subject line
      text: message, // plain text body
      html: message
  },function(){
    res.json('Mail sent!');
  }).catch(err => {
    res.json("Couldn't send the mail for some reason");
  });

  console.log('Message sent: %s', info.messageId);
  // Message sent: <[e-mail]>

  // Preview only available when sending through an Ethereal account
  console.log('Preview URL: %s', nodemailer.getTestMessageUrl(info));
  // Preview URL: https://ethereal.email/message/WaQKMgKddxQDoou...
});

这会收到一封“已发送邮件！”来自服务器的响应，但服务器抛出此错误：unhandledPromisejectionWarning:TypeError:无法读取未定义的的属性“catch”，并且它不会记录messageID或预览url，因此我不确定它是否真的发送了邮件。

我试图在捕获之前将err作为参数传递给函数，但没有帮助。

我还尝试过完全移除捕获物（见下文）：

myRoutes.route('/send-mail').post(async function(req, res) {
  let testAccount = await nodemailer.createTestAccount();

  // create reusable transporter object using the default SMTP transport
  let transporter = nodemailer.createTransport({
      host: 'smtp.ethereal.email',
      port: 587,
      secure: false, // true for 465, false for other ports
      auth: {
          user: testAccount.user, // generated ethereal user
          pass: testAccount.pass // generated ethereal password
      }
  });

  let senderName = req.body.senderName;
  let senderEmail = req.body.senderEmail;
  let subject = req.body.subject;
  let message = req.body.message;
  let toEmail = req.body.toEmail;

  // send mail with defined transport object
  let info = await transporter.sendMail({
      from: `"${senderName}" <${senderEmail}>`, // sender address
      to: toEmail, // receiver address
      subject: subject, // Subject line
      text: message, // plain text body
      html: message
  },function(){
    res.json('Mail sent!');
  });

  console.log('Message sent: %s', info.messageId);
  // Message sent: <[e-mail]>

  // Preview only available when sending through an Ethereal account
  console.log('Preview URL: %s', nodemailer.getTestMessageUrl(info));
  // Preview URL: https://ethereal.email/message/WaQKMgKddxQDoou...
});

这会得到邮件发送！再次响应，但服务器现在抛出此错误：UnhandledPromiseRejtionWarning： TypeError：无法读取未定义的属性'MessageId'

你知道我该怎么做吗？我只需要一个简单的联系表单，当它提交时，会从服务器返回一个状态的响应，告诉我们邮件是否已发送。

Answer 1

您忘记添加退货，请尝试以下方法：

let info = await transporter.sendMail({
      from: `"${senderName}" <${senderEmail}>`, // sender address
      to: toEmail, // receiver address
      subject: subject, // Subject line
      text: message, // plain text body
      html: message
  }).then((data)=>{return data}).catch((error)=> {return error});

if(info.messageId){
   console.log('Message sent: %s', info.messageId);
   res.json({message:'Mail sent!'});
}else{
   console.log('Message Not sent');
   res.json({message:'Mail not sent!'});
}