通过 nodemailer 向多个收件人发送电子邮件

Question

我正在尝试向多个收件人发送电子邮件。为此，我创建了一个收件人数组，但使用我的代码，我只能将邮件发送到数组的最后一个电子邮件 ID 三次。我的代码有什么问题？

var nodemailer = require("nodemailer");

var smtpTransport = nodemailer.createTransport(
"SMTP",{
  host: '',
  //  secureConnection: true,         // use SSL
  port: 25
});

var maillist = [
  '****.sharma3@****.com',
  '****.bussa@****.com',
  '****.gawri@****.com',
];

var msg = {
    from: "******", // sender address
    subject: "Hello ✔", // Subject line
    text: "Hello This is an auto generated Email for testing  from node please ignore it  ✔", // plaintext body
    cc: "*******"    
    //  html: "<b>Hello world ✔</b>" // html body
}


maillist.forEach(function (to, i , array) {
  msg.to = to;

  smtpTransport.sendMail(msg, function (err) {
    if (err) { 
      console.log('Sending to ' + to + ' failed: ' + err);
      return;
    } else { 
      console.log('Sent to ' + to);
    }

    if (i === maillist.length - 1) { msg.transport.close(); }
  });
});

Answer 1

nodemailer (v2.4.2) docs 说：

to - 将出现在“收件人：”字段中的逗号分隔列表或收件人电子邮件地址数组

所以你可以这样做：

var maillist = [
  '****.sharma3@****.com',
  '****.bussa@****.com',
  '****.gawri@****.com',
];

var msg = {
    from: "******", // sender address
    subject: "Hello ✔", // Subject line
    text: "Hello This is an auto generated Email for testing  from node please ignore it  ✔", // plaintext body
    cc: "*******",
    to: maillist
}

Answer 2

据我所知，您将能够收到多个这样的收件人

"mail1@mail.com,mail2@mail.com,mail3@mail.com,mail4@mail.com"

那你为什么不做类似的事情

var maillist = '****.sharma3@****.com, ****.bussa@****.com, ****.gawri@****.com';

var msg = {
    from: "******", // sender address
    to: maillist,
    subject: "Hello ✔", // Subject line
    text: "Hello This is an auto generated Email for ...  ✔", // plaintext body
    cc: "*******"    
    //  html: "<b>Hello world ✔</b>" // html body
}

我已经尝试过了，它正在工作。此外，从我的角度来看，如果您有发送能力，为什么还要担心“异步”或发送电子邮件 1K 次 所有这些都只需一次，没有任何复杂性？

无论如何希望这会有所帮助，回答您的问题，或者它可能对其他人有所帮助

当然，我的答案可以改进..

Answer 3

您的问题是从异步代码中引用相同的 msg 对象。 foreach 在 sendMail 发送电子邮件之前完成。

所以 msg.to 将是 maiilist 对象的最后一项。

尝试在邮件列表 foreach 中克隆/复制 msg，或者只是将 msg 定义移动到那里：

maillist.forEach(function (to, i , array) {


  var msg = {
        from: "******", // sender address
        subject: "Hello ✔", // Subject line
        text: "Hello This is an auto generated Email for testing  from node please ignore it  ✔", // plaintext body
        cc: "*******"    
        //  html: "<b>Hello world ✔</b>" // html body
    }
  msg.to = to;

  smtpTransport.sendMail(msg, function (err) {

Answer 4

var maillist = [
  '****.sharma3@****.com',
  '****.bussa@****.com',
  '****.gawri@****.com',
];

maillist.toString();

var msg = {
    from: "******", // sender address
    to: maillist,
    subject: "Hello ✔", // Subject line
    text: "Hello This is an auto generated Email for testing  from node please ignore it  ✔", // plaintext body
    cc: "*******"    
    //  html: "<b>Hello world ✔</b>" // html body
}

Answer 5

异步执行此操作的一个好方法是使用 async 模块中的 each 函数：https://caolan.github.io/async/docs.html#each

var async = require("async");

async.each(maillist, function(to, callback){

    msg.to = to;

    smtpTransport.sendMail(msg, function (err) {
        if (err) { 
            console.log('Sending to ' + to + ' failed: ' + err);
            callback(err);
        } else { 
            console.log('Sent to ' + to);
            callback();
        }
    });
}, function(err){
    if(err){
        console.log("Sending to all emails failed:" + err);
    }

    //Do other stuff or return appropriate value here
});

Answer 6

let info = await transporter.sendMail({
  from: [{ name: "sender Name", address: "sender@example.com" }], // sender address
  to: [
    { name: "Receiver Name 1", address: "receiver1@example.com" },
    { name: "Receiver Name 2", address: "receiver2@example.com" },
  ],
  subject: "Hey you, awesome!",
  html: "<b>This is bold text</b>",
  text: "This is text version!",
});

• 您可以将电子邮件发送给多个收件人，方法是将名称保留在对象数组中，其中名称是收件人姓名，地址是收件人电子邮件地址。
• 通过上述方式，我可以向多个收件人发送电子邮件。

Answer 7

sendMail 方法实际上是在 forEach 循环结束后得到解决，但问题是 sendMail 方法没有返回类型的 promise，所以如果你尝试等待它，它仍然无法工作。

所以你需要做的是为 sendmail 创建一个单独的函数，从而使它成为这样的承诺

    const send = (transporter: any, mailOptions: any) => {
    return new Promise((resolve, reject) => {
        transporter.sendMail(mailOptions, (error: any, info: any) => {
          if (error) {
            return reject(error);
          } else {
            return resolve();
          }
        });
    });
    };

所以这可以等待这个，因此迭代器将在进入下一个循环之前等待进程完成。

完整的代码应该是这样的

    let transporter = nodemailer.createTransport({
      host: "mail.smtp.com", // your server host address
      port: 587, // port
      secure: false, // use TLS // true for 465, false for other ports
      auth: {
        user: EMAIL_USER, // your email address
        pass: EMAIL_PSW, // your password
      },
      tls: {
        rejectUnauthorized: false
      }
    });

    // store an array of errors if any
    let successful: any[] = [];
    let failed: any[] = [];
    await recipients.forEach(async (to, i) => {
      let mailOptions = {
        from, // sender address
        to, // list of receivers
        subject, // Subject line
        text // plain text body
      };

      if (html) {
        (mailOptions as any).html = html;
      }

      // send mail with defined transport object
      // here we use the fuction we created which is now a promise
      await send(transporter, mailOptions)
        .then(() => {
          successful.push({ success: true, to });
        })
        .catch(reason => {
          failed.push({ success: false, to, message: reason });
        });
      if (i === recipients.length - 1) {
        if (failed.length === recipients.length) {
          return reject({ failed });
        } else {
          return resolve({ successful, failed });
        }
      }
    });
  });


const send = (transporter: any, mailOptions: any) => {
return new Promise((resolve, reject) => {
    transporter.sendMail(mailOptions, (error: any, info: any) => {
      if (error) {
        return reject(error);
      } else {
        return resolve();
      }
    });
});
};

Answer 8

您正在异步发送电子邮件，因此您需要一个等待功能来等待所有邮件，直到它们被发送，因为如果没有，您的程序将退出并且某些请求没有得到满足。因此，您必须执行某种超时功能来检查电子邮件是否已发送。

Answer 9

maillist.forEach(function (to, i , array) {
  (function(i,to){
     msg.to = to;
  smtpTransport.sendMail(msg, function (err) {
    if (err) { 
      console.log('Sending to ' + to + ' failed: ' + err);
      return;
    } else { 
      console.log('Sent to ' + to);
    }

    if (i === maillist.length - 1) { msg.transport.close(); }
  });
})(i,to)
});