Bluebird - promisification - promisifyAll of 'email-templates' Node Module - Send mail - node.js

Question

I am trying to convert email-templates node module into promise. I am using bluebird for promisification but it couldn't converted.
var emailTemplates = Promise.promisifyAll(require('email-templates'));
Is promisification node module supports this conversion or Am I doing any mistake?
EDITED :
I am doing like this now but wanna convert this to bluebird promise.
var emailTemplates = require('email-templates');
var path = require('path');
var templatesDir = path.resolve(__dirname, '../..', 'assets/templates');
var postmark = require('postmark');
var postmarkKey = MY_POSTMARK_KEY;
var postmarkClient = postmark(postmarkKey);
module.exports = {
sendEmail : function (templateName, locals, callback) {
emailTemplates(templatesDir, function (err, template) {
if (err)
return callback(err, null);
else {
template(templateName, locals, function (err, html, text) {
if (err) {
return callback(err, null);
}
else {
postmarkClient.send({
From: locals.from,
To: locals.to,
Subject: locals.subject,
HtmlBody: html
TextBody: text
}, function (err, responseStatus) {
if (err) {
return callback(err, null);
}
else {
return callback(err, responseStatus);
}
});
}
});
}
});
}
}

Answer 1

emailTemplates is a function, so you'd do:
var emailTemplates = Promise.promisify(require('email-templates'));
The problem is that it does not behave well since the function itself has a callback argument, so you'd have to do:
emailTemplates().then(function(template){
Promise.fromNode(template.bind(null, "template-name")).then(...
});

Answer 2

Promisify missbehaved for me as well, so i made a manual promisification.
var postmark = require("postmark");
var client = new postmark.Client("POSTMARK_API_TEST");
var Promise = require('bluebird');
exports.sendInviteEmail = function(email) {
let promise = new Promise((resolve, reject) => {
client.sendEmail({
"From": "donotreply#example.com",
"To": "target#example.us",
"Subject": "Test",
"TextBody": "Test Message"
}, function(error, result) {
if(error) {
reject(error);
} else {
resolve(result);
}
})
});
return promise;
}