Gmail blocks Nodemailer from sending mail

Question

I am working on deploying my Node.js app. However I am having issues with having the registration email getting sent out.

const transporter = nodemailer.createTransport({
    service: 'Gmail',
    auth: {
        user: GMAIL_USER,
        pass: GMAIL_PASS,
    },
});
......
......
transporter.sendMail({
                        to: newUser.email,
                        subject: 'Confirm Email',
                        html: `Please click this email to confirm your email: <a href="${url}">${url}</a>`
                    });

This works perfectly when I try running it on local host, but as soon as I upload the files to my server and try it, google blocks the sign in attempt, and I get an email saying

Someone just used your password to try to sign in to your account. Google blocked them, but you should check what happened.

Every time, I click the button "this was me", but any future attempts still get blocked.

I have "less secure apps" enabled. Is there a way to whitelist an IP to send from my gmail? or a way to get this working in general?

Answer 1

You have two options.Either you set the access to less secure apps setting to Enabled or you obtain an accessToken and a refreshToken from Google OAuth2.0 and use them in your nodemailer config

• For option one go to https://www.google.com/settings/security/lesssecureapps
• For option two go to https://console.developers.google.com/apis/credentials

if you choose option two your config for the transport will look something like this:

auth: {
    type: 'OAuth2',
    user: '[email protected]',
    accessToken: 'ya29.Xx_XX0xxxxx-xX0X0XxXXxXxXXXxX0x'
}