does nodemailer prevent fs.writeFile from working - node.js

Question

I m trying to write form data to a json database file, while also using nodeMailer to either before or after the writeFile, problem is that with my code, only the writeFile appears to be executing while the nodeMailer doesn't execute, however, if i omit the file Write, then the nodeMailer executes and i m able to send email. can any one advice on how I can run both tasks?
const messageDB = {
messages: require('../models/messageDB.json'),
setMessage: function (data) {
this.messages = data
}
}
const { body, validationResult } = require('express-validator')
const fs = require('fs')
const path = require('path')
const nodemailer = require('nodemailer')
exports.message_controller_get = (req, res, next) => {
res.render('index')
}
exports.message_controller_post = [
body('name', 'Full names must be specified').isLength({ min: 2, max: 40 }).trim(),
body('email', 'Email address must be specified').isEmail().isLength({ min: 3, max: 40 }),
body('msg', 'Message must be specified').isLength({ min: 20, max: 1000 }),
(req, res, next) => {
const errors = validationResult(req)
if (!errors.isEmpty()) {
console.log('there are errors: ' + errors.array())
return
}
const message = {
name: req.body.name,
email: req.body.email,
msg: req.body.msg
}
const transporter = nodemailer.createTransport({
host: 'smtp.ethereal.email',
port: 587,
auth: {
user: 'lila.greenfelder71#ethereal.email',
pass: 'DQnhbPkHBRzPU1UkAt'
}
});
const mailOption = {
from: 'Fred Foo 👻" <fred#homexclusiv.com>',
to: 'payiyke#gmail.com',
subject: `Message from ${req.body.email}:`,
text: req.body.msg
}
messageDB.setMessage([...messageDB.messages, message])
fs.writeFile(
path.join(__dirname, '..', 'models', 'messageDB.json'),
JSON.stringify(messageDB.messages),
(err) => {
if (err){
return res.send(err)
} else {
transporter.sendMail(mailOption, (error, info) => {
if (error) {
console.log(error);
res.send('error')
} else {
console.log('Email sent :' + info.response)
res.send('success')
}
})
/* return res.send('success') */
}
}
)
/* console.log(`${message.name}\t${message.email}`) */
}
]
not to worry, password is temporary

Answer 1

It's likely that the writeFile method is completing before the nodemailer code block can execute. You can try to put the nodemailer code block in a separate function and call it after the writeFile method completes.
This way, the writeFile method will be executed first and then the sendEmail function will be called. The sendEmail function will then execute the nodemailer code block to send the email.
You can try something like this
const messageDB = {
messages: require('../models/messageDB.json'),
setMessage: function (data) {
this.messages = data
}
}
const { body, validationResult } = require('express-validator')
const fs = require('fs')
const path = require('path')
const nodemailer = require('nodemailer')
exports.message_controller_get = (req, res, next) => {
res.render('index')
}
exports.message_controller_post = [
body('name', 'Full names must be specified').isLength({ min: 2, max: 40 }).trim(),
body('email', 'Email address must be specified').isEmail().isLength({ min: 3, max: 40 }),
body('msg', 'Message must be specified').isLength({ min: 20, max: 1000 }),
(req, res, next) => {
const errors = validationResult(req)
if (!errors.isEmpty()) {
console.log('there are errors: ' + errors.array())
return
}
const message = {
name: req.body.name,
email: req.body.email,
msg: req.body.msg
}
const transporter = nodemailer.createTransport({
host: 'smtp.ethereal.email',
port: 587,
auth: {
user: 'lila.greenfelder71#ethereal.email',
pass: 'DQnhbPkHBRzPU1UkAt'
}
});
const mailOption = {
from: 'Fred Foo 👻" <fred#homexclusiv.com>',
to: 'payiyke#gmail.com',
subject: `Message from ${req.body.email}:`,
text: req.body.msg
}
messageDB.setMessage([...messageDB.messages, message])
fs.writeFile(
path.join(__dirname, '..', 'models', 'messageDB.json'),
JSON.stringify(messageDB.messages),
(err) => {
if (err){
return res.send(err)
} else {
sendEmail(transporter, mailOption, res);
}
}
)
/* console.log(`${message.name}\t${message.email}`) */
}
]
function sendEmail(transporter, mailOption, res) {
transporter.sendMail(mailOption, (error, info) => {
if (error) {
console.log(error);
res.send('error')
} else {
console.log('Email sent :' + info.response)
res.send('success')
}
})
}