vtex-email-framework/server/app.js

Transactional emails development architecture

const { existsSync, readdirSync } = require('node:fs');
const { resolve } = require('node:path');
const app = require('express')();
const hbs = require('hbs');
const cors = require('cors');

const root = (folders)=> {
    return resolve(process.cwd(), ...folders.split('/'));
}
const helper = readdirSync(root('emails/helpers'))[0].replace('.js', '');
require(resolve(process.cwd(),'emails', 'helpers', helper));

hbs.registerHelper('clearText', (value) => value.replace(/\W+/g, ' '));
hbs.registerPartials(root('emails/templates/custom/partials'), function (err) { });

function findModel(templateName) {
    if (existsSync(root('emails/templates/default'))) {
        if (readdirSync(root('emails/templates/default')).includes(templateName)) return templateName
    }
    return null
}

const viewFiles = readdirSync(root('emails/templates/custom'));
const fileNames = viewFiles
    .filter(folder => /.hbs$/gi.test(folder))
    .map(template => {
        return {
            file: template.split('.')[0],
            model: findModel(template)
        }
    });


app.use(cors())
app.set('views', root('emails/templates/custom'));
app.set('view engine', 'hbs');

app.get('/', (req, res) => {
    res.render(resolve(__dirname, 'view'), { files: fileNames })
});

app.get('/sse', (req, res) => {
    res.statusCode = 200;
    res.setHeader("cache-control", "no-cache")
    res.setHeader("connection", "keep-alive")
    res.setHeader("content-type", "text/event-stream")
    res.write('retry: 200\n');
});

fileNames.forEach(({ file }) => {
    app.get(`/${file}`, (req, res) => {
        res
        .render(file, require(root(`emails/json/${file}.json`)))
    })
    app.get(`/templates/default/${file}`, (req, res) => {
        res
        .render(root(`emails/templates/default/${file}`), require(root(`emails/json/${file}.json`)))
    })
});

module.exports = app