javascript - Pass variable to html template in nodemailer

Question

I want to send email with nodemailer using html template. In that template I need to inject some dynamically some variables and I really can't do that. My code:

var nodemailer = require('nodemailer');
var smtpTransport = require('nodemailer-smtp-transport');

smtpTransport = nodemailer.createTransport(smtpTransport({
    host: mailConfig.host,
    secure: mailConfig.secure,
    port: mailConfig.port,
    auth: {
        user: mailConfig.auth.user,
        pass: mailConfig.auth.pass
    }
}));
var mailOptions = {
    from: 'my@email.com',
    to : 'some@email.com',
    subject : 'test subject',
    html : { path: 'app/public/pages/emailWithPDF.html' }
};
smtpTransport.sendMail(mailOptions, function (error, response) {
    if (error) {
        console.log(error);
        callback(error);
    }
});

Let's say I want in emailWithPDF.html something like this:

Hello {{username}}!

I've found some examples, where was smth like this:

...
html: '<p>Hello {{username}}</p>'
...

but I want it in separate html file. Is it possible?

Answer 1

What you can do is read the HTML file using fs module in node and then replace the elements that you want changed in the html string using handlebars

var nodemailer = require('nodemailer');
var smtpTransport = require('nodemailer-smtp-transport');
var handlebars = require('handlebars');
var fs = require('fs');

var readHTMLFile = function(path, callback) {
    fs.readFile(path, {encoding: 'utf-8'}, function (err, html) {
        if (err) {
            throw err;
            callback(err);
        }
        else {
            callback(null, html);
        }
    });
};

smtpTransport = nodemailer.createTransport(smtpTransport({
    host: mailConfig.host,
    secure: mailConfig.secure,
    port: mailConfig.port,
    auth: {
        user: mailConfig.auth.user,
        pass: mailConfig.auth.pass
    }
}));

readHTMLFile(__dirname + 'app/public/pages/emailWithPDF.html', function(err, html) {
    var template = handlebars.compile(html);
    var replacements = {
         username: "John Doe"
    };
    var htmlToSend = template(replacements);
    var mailOptions = {
        from: 'my@email.com',
        to : 'some@email.com',
        subject : 'test subject',
        html : htmlToSend
     };
    smtpTransport.sendMail(mailOptions, function (error, response) {
        if (error) {
            console.log(error);
            callback(error);
        }
    });
});