lora-project/server-api/libs/sendmail.js

const nodemailer = require('nodemailer')
const config = require('../config.json')
const util = require('util')

module.exports = async(toMail, template = {}, data = []) => {
  let transporter = nodemailer.createTransport({
    host: config.smtp.host,
    port: config.smtp.port,
    secure: config.smtp.secure, // secure:true for port 465, secure:false for port 587
    auth: {
      user: config.smtp.user,
      pass: config.smtp.pass
    }
  })

    // setup email data with unicode symbols
  let mailOptions = {
    from: config.smtp.sys_mail, // sender address
    to: toMail, // list of receivers
    subject: template.title || '', // Subject line
    text: template.text ? util.format(template.text, ...data) : '', // plain text body
    html: template.html ? util.format(template.html, ...data) : '' // html body
  }

  return new Promise((resolve, reject) => {
        // send mail with defined transport object
    transporter.sendMail(mailOptions, (error, info) => {
      if (error) {
        return reject(error)
      }
            // console.log('Mepassage %s sent: %s', info.messageId, info.response);
      return resolve(info)
    })
  })
}