Nodemailer with Gmail service not working on heroku - node.js

Question

I've got a basic email setup done for sending an email using Nodemailer with AngularJS and NodeJS and I've got the project deployed on heroku.
The emailing seems to be working just fine when I am running the app on heroku, but when I get it deployed to Heroku no emails are sent.
For authentication, I am using a Gmail address and I also have a bcc to another Gmail address. So from and bcc addresses are two different Gmail addresses. The from address is the same as the address used for authentication.
Could somebody help me with resolving this issue?
Edit: Adding code
var nodemailer = require('nodemailer');
var transporter = nodemailer.createTransport({
service: 'Gmail',
auth: {
user: 'foobar#gmail.com',
pass: 'foobar'
}
});
router.post('/send',function(req,res){
var mailOptions = {
from: 'Foo Bar ✔ <foobar#gmail.com>',
to: req.body.email,
subject: "Hello " + req.body.email,
text: 'Hello ' + req.body.email + '✔',
html: "<p>Hello " + req.body.email + " </p>",
bcc: "fred#gmail.com"
};
transporter.sendMail(mailOptions, function(error, info){
if(error){
console.log(error);
}else{
console.log('Message sent: ' + info.response);
res.send(200);
}
});
});

Answer 1

I believe this is an issue with google account security.
Google blocked your sign-in to use the mailing features due to an unknown device (location).
A few step to verify this:
Start your server locally and sends the email.
Check your account alerts for unknown sign-in.
This can be temporally resolved by:
https://accounts.google.com/DisplayUnlockCaptcha
A more permanent resolution would be to change your password to a stronger level:
upper case letter + lower case letter + special symbols + numbers

Answer 2

Instead of using direct gmail credentials like this
auth: {
user: 'foobar#gmail.com',
pass: 'foobar'
}
Use OAuth2
auth: {
type: 'OAuth2',
user: 'user#example.com',
accessToken: 'ya29.Xx_XX0xxxxx-xX0X0XxXXxXxXXXxX0x'
}
Google blocks the heroku IPs (unsafe), if we are using direct credentials like you mentioned above. You can refer this Medium article here

Answer 3

5 years later, I still struggled this problem (all answers found on SO failed in my case). Here is what I did, for now everything works smoothly:
Install SendGrid addon to your Heroku app (Free plan gives you 12k messages a month)
Go to SendGrid panel
Go to Marketing -> Senders to add your sender bot, configure it like this:
From = any_address#heroku.com
Reply = your_gmail#gmail.com
Generate API KEY here
Configure NodeMailer like so:
const nodemailer = require('nodemailer'),
sgTransport = require('nodemailer-sendgrid-transport');
const mailTransporter = nodemailer.createTransport(sgTransport({
auth: {
api_key: process.env.ADMIN_EMAIL_API_KEY // your api key here, better hide it in env vars
}
}))
To send an email now, you have to add your gmail in 'Reply To' field, like so:
mailTransporter.sendMail({
from: `"Admin" <any_address#heroku.com>`,
to: 'receiver#hotmail.com',
replyTo: 'your_gmail#gmail.com',
subject: 'Something',
html: `Boom !`
});
I think that's all, in case I forgot something, please add a comment below

Answer 4

Try updating nodemailer package (using "npm update nodemailer" command)
var transporter = nodemailer.createTransport({
host: 'smtp.gmail.com',
port: 465,
secure: true,
auth: {
user: 'youremai#gmail.com', // Your email id
pass: 'pwd123' // Your password
},
tls: {
// do not fail on invalid certs
rejectUnauthorized: false
}
});
router.post('/send',function(req,res){
var mailOptions = {
from: 'Foo Bar ✔ <foobar#gmail.com>',
to: req.body.email,
subject: "Hello " + req.body.email,
text: 'Hello ' + req.body.email + '✔',
html: "<p>Hello " + req.body.email + " </p>",
bcc: "fred#gmail.com"
};
transporter.sendMail(mailOptions, function(error, info){
if(error){
console.log(error);
}else{
console.log('Message sent: ' + info.response);
res.send(200);
}
});
});

Answer 5

I know I'm too late but hopefully someone will find it helpful.
At the time of writing, Less Secure Apps is no longer supported by google.
And you can't use your google account password.
You're gonna have to generate a new app password.
Follow this link
In the "Select App" dropdown, select Other and give the app a name (could be anything)
Copy the password and replace it with your original password
It works on Local machine and Heroku.
const client = nodemailer.createTransport({
service: "Gmail",
auth: {
user: "username#gmail.com",
pass: "Google-App-Password-Without-Spaces"
}
});
client.sendMail(
{
from: "sender",
to: "recipient",
subject: "Sending it from Heroku",
text: "Hey, I'm being sent from the cloud"
}
)
App passwords only work if 2-step verification is turned on. You can do so here

Answer 6

Also if your app password is in your .env file you have to add it to the config vars in the settings tab of your app at heroku.