How to make nodemailer reusable in multiple module? - node.js

Question

I have implemented nodemailer after the user registration, in the following way:
let transporter = nodemailer.createTransport({
service: 'gmail',
auth: {
user: process.env.EMAIL_USERNAME,
pass: process.env.EMAIL_PASSWORD
}
});
let mailOptions = {
from: process.env.EMAIL_USERNAME,
to: user.email,
subject: 'Verify your account',
text: 'Click here for verify your account'
};
transporter.sendMail(mailOptions, (error, info) => {
if (error) {
return console.log(error);
}
});
I don't like much this code because if I need to send an email in another module, I need to rewrite all the stuff above.
Since I'm new to NodeJS, I would like to know if I can remove this code redundancy make something like a utility or maybe an helper class. The goal is import the wrapper class and call a simple function to send the email.
Which is the best way to handle that?

Answer 1

I refactored your code to look like below and then save it as mail.js
let transporter = nodemailer.createTransport({
service: 'gmail',
auth: {
user: process.env.EMAIL_USERNAME,
pass: process.env.EMAIL_PASSWORD
}
});
let sendMail = (mailOptions)=>{
transporter.sendMail(mailOptions, (error, info) => {
if (error) {
return console.log(error);
}
});
};
module.exports = sendMail;
in Your other modules, say activation.js
var mailer = require('./mail.js');
mailer({
from: process.env.EMAIL_USERNAME,
to: user.email,
subject: 'Verify your account',
text: 'Click here for verify your account'
};);

Answer 2

you can use module.exports as follow :
create common service mail.js and write your mail sent code here
mails.js
module.exports = function (){
// mail sent code
}
require mail.js where you write mail sent code in other service and call mail sent function
otherService.js
var mail = require('mail.js') // require mail sent in other service where you want to send mail
mail.sent() // call function of mail.js

Answer 3

I have created a class for this:
import NodeMailer from 'nodemailer'
import emailConfig from '../../config/mail' // read email credentials from your config
class EmailSender {
transport
constructor() {
this.transport = NodeMailer.createTransport({
host: emailConfig.MAIL_HOST,
port: emailConfig.MAIL_PORT,
auth: {
user: emailConfig.MAIL_USERNAME,
pass: emailConfig.MAIL_PASSWORD,
},
})
}
async sendMessage(to, subject, text, html) {
let mailOptions = {
from: emailConfig.MAIL_FROM_ADDRESS,
to,
subject,
text,
html,
}
await this.transport.sendMail(mailOptions)
}
}
export default new EmailSender()
Now you can implement it in your any routes:
router.get('/email', async (req, res) => {
try {
await EmailSender.sendMessage(
'bijaya#bijaya.com',
'Hello world',
'test',
'<h1>Test</h1>'
)
return res.status(200).send('Successfully sent email.')
} catch (exception) {
return res.status(500).send(exception.message)
}
})