npm install nodemailer --save

var nodemailer = require("nodemailer");

// 開啟一個 SMTP 連接池
var smtpTransport = nodemailer.createTransport("SMTP",{
  host: "smtp.qq.com", // 主機
  secureConnection: true, // 使用 SSL
  port: 465, // SMTP 端口
  auth: {
    user: "xxxxxxxx@qq.com", // 賬號
    pass: "xxxxxxxx" // 密碼
  }
});

// 設置郵件內容
var mailOptions = {
  from: "Fred Foo <xxxxxxxx@qq.com>", // 發件地址
  to: "2838890xx@qq.com, minimixx@126.com", // 收件列表
  subject: "Hello world", // 標題
  html: "<b>thanks a for visiting!</b> 世界，你好！" // html 內容
}

// 發送郵件
smtpTransport.sendMail(mailOptions, function(error, response){
  if(error){
    console.log(error);
  }else{
    console.log("Message sent: " + response.message);
  }
  smtpTransport.close(); // 如果沒用，關閉連接池
});

{ [AuthError: Invalid login - 454 Authentication failed, please open smtp flag first!]
  name: 'AuthError',
  data: '454 Authentication failed, please open smtp flag first!',
  stage: 'auth' }

{ [SenderError: Mail from command failed - 501 mail from address must be same as authorization user]
  name: 'SenderError',
  data: '501 mail from address must be same as authorization user',
  stage: 'mail' }