React + NodeJS - nodemailer google cloud functions

Question

I am trying to make a reactJS app, and would like to when people ended up filling the form to send some emails.

for that, I have firstly created a sendGrid function but did not like so much the delay and the email templates (and the fact that is more than 100 mails per day.

then I read that I could use Nodemailer + (or without) express + firebase and google cloud functions. I wrote this function:

exports.mailSun = functions.https.onRequest((req, res) => {
  const { name, dest } = req.query;

  var transporter = nodemailer.createTransport({
    service: 'Gmail',
    host: 'smtp.gmail.com',
    port: 465,
    secure: true,
    auth: {
        user: 'xxx@gmail.com',
        pass: 'xxx'
  }
  });
  const mailOptions = {
    from: 'hello@sunny.com', // sender address
    to: 'pedrospecter@gmail.com', // list of receivers
    subject: 'Elavtal', // Subject line
    html: '<p>Grattis för ditt nya avtal. Elbolag kommer att kontakta dig inom kort.</p>'// plain text body
  };

return transporter.sendMail(mailOptions, function (err, info) {
  if(err)
    console.log(err)
  else
    console.log(info);
});
}); 

then I tried

exports.sendMail= functions.https.onRequest((req, res) => {

  cors(req, res, () => {

      // getting dest email by query string
      const { name, dest } = req.query;
      var transporter = nodemailer.createTransport({
        service: 'Gmail',
          host: "smtp.gmail.com",
          port: 465,
          secure: true,
          auth: {
              user: 'xxx@gmail.com',
              pass: 'xxx'
        }
        });
      const mailOptions = {
          from: 'Sunny <xxxb@gmail.com>', // Something like: Jane Doe <janedoe@gmail.com>
          to: 'xxx@mail.com',
          subject: 'nytt Avtal', // email subject
          text: `<p Ni har fått ett nytt avtal. Logga in på Sunny för att se kunddetaljer.</p> ` // email content in HTML
      };

      // returning result
      return transporter.sendMail(mailOptions, (erro, info) => {
          if(erro){
              return res.send(erro.toString());
          }
          return res.send('Sent');
      });
  });    
});

can someone help me with what is wrong?

Answer 1

Instead of using the callback version of the sendMail() method, use the Promise version, as follows:

exports.mailSun = functions.https.onRequest((req, res) => {
    const { name, dest } = req.query;

    var transporter = nodemailer.createTransport({
        service: 'Gmail',
        host: 'smtp.gmail.com',
        port: 465,
        secure: true,
        auth: {
            user: 'xxx@gmail.com',
            pass: 'xxx'
        }
    });
    const mailOptions = {
        from: 'hello@sunny.com', // sender address
        to: 'pedrospecter@gmail.com', // list of receivers
        subject: 'Elavtal', // Subject line
        html: '<p>Grattis för ditt nya avtal. Elbolag kommer att kontakta dig inom kort.</p>'// plain text body
    };

    return transporter.sendMail(mailOptions)
        .then(info => {
            res.send("email sent");
        })
        .catch(err => {
            console.log(err);
            res.status(500).send("Error sending mail")
        })
});

See the doc

If callback argument is not set then the method returns a Promise object. Nodemailer itself does not use Promises internally but it wraps the return into a Promise for convenience. If callback is not defined for sendMail then the method returns a native Promise object instead

Answer 2

I'm guessing you are trying to login with login / password but you are creating your transport with oauth2 settings moreover you should remove the from key in the options as gmail will override it with your email (I don't know if it create an error tho). I also noticed that you use the text key for your mail options but sending html while there is an html key available (maybe it is causing some issue).

const gmailEmail = functions.config().gmail.email;
const gmailPassword = functions.config().gmail.password;


// create transport 
const mailTransport = nodemailer.createTransport({
  service: "gmail",
  auth: {
    user: gmailEmail,
    pass: gmailPassword
  }
});

exports.sendMail= functions.https.onRequest((req, res) => {

  cors(req, res, () => {


      const mailOptions = {
          to: 'xxx@mail.com',
          subject: 'nytt Avtal', // email subject
          text: `<p Ni har fått ett nytt avtal. Logga in på Sunny för att se kunddetaljer.</p> ` // email content in HTML
      };

      // returning result
      return transporter.sendMail(mailOptions, (erro, info) => {
          if(erro){
              return res.send(erro.toString());
          }
          return res.send('Sent');
      });
  });    
});

There is also some config to do with your google account

• accept less secure apps google security

• turn off capatcha unlock captcha

You can test your function and see errors inside google cloud functions console gcp / functions it helped me debug the same issue.