SMTP 使用 Nodemailer 发送错误 email

Question

我正在构建一个 web 应用程序，我想向忘记密码的注册用户发送电子邮件。 但是我在通过节点邮件发送邮件时遇到问题。 我不断收到 421 响应错误，表明服务器正忙于连接太多，我不明白为什么。

下面是我的代码和我不断收到的错误。

require('dotenv').config()
const nodeMailer = require('nodemailer')


const sendMail = async (email, token) => {
    const transporter = nodeMailer.createTransport({
      host: process.env.EMAIL_HOST,
      port: 587,
      auth: {
        user: process.env.EMAIL_USER,
        pass: process.env.EMAIL_PASSWORD,
      },
    });
    console.log("passed transportrt ");
    await transporter.sendMail({
        from: process.env.EMAIL_USER,
        to: email,
        subject: "Password RESET",
        text: `Follow this link to reset your password. It expires in 15minutes. \n\n
         http://localhost:4000/reset/${token}`,
    });
    console.log('out') 
}

module.exports = sendMail

其他部分和工作流程运行良好，直到await transporter.sendMail({...这是我一直在下面遇到的错误

Error: Invalid greeting. response=421 Service not available: 421 Service not available
    at SMTPConnection._actionGreeting (.../node_modules/nodemailer/lib/smtp-connection/index.js:1205:27)
    at SMTPConnection._processResponse (.../node_modules/nodemailer/lib/smtp-connection/index.js:947:20)
    at SMTPConnection._onData (.../node_modules/nodemailer/lib/smtp-connection/index.js:749:14)
    at Socket.SMTPConnection._onSocketData (.../node_modules/nodemailer/lib/smtp-connection/index.js:189:44)
    at Socket.emit (node:events:526:28)
    at addChunk (node:internal/streams/readable:315:12)
    at readableAddChunk (node:internal/streams/readable:289:9)
    at Socket.Readable.push (node:internal/streams/readable:228:10)
    at TCP.onStreamRead (node:internal/stream_base_commons:190:23) {
  code: 'EPROTOCOL',
  response: '421 Service not available',
  responseCode: 421,
  command: 'CONN'
}

我可能做错了什么吗？ 另外我在 unbuntu 上运行这个（如果它与错误有任何联系）

Answer 1

带有 EPROTOCOL 错误的 421 错误通常意味着邮件客户端无法连接到邮件服务器。 检查两种简单的可能性：

• process.env.EMAIL_HOST未定义（未在.env文件或操作系统中设置）
• 您的服务器无法通过端口 587 连接到邮件主机（使用 te.net 很容易检查）。