index.js

"use strict";

const fs = require("fs");
const express = require("express");
const path = require("path");
const app = express();

// app.use(require('morgan')('dev'));

app.use("/updates/releases", express.static(path.join(__dirname, "releases")));

app.get("/updates/:productName/latest", (req, res) => {
    const productName = req.param("productName");
    const latest = getLatestRelease(productName);
    const clientVersion = req.query.v;

    if (clientVersion === latest) {
        res.status(204).end();
    } else {
        res.json({
            url: `${getBaseUrl()}/updates/releases/${productName}/darwin/${latest}/${productName}.zip`
        });
  }
});

let getLatestRelease = (productName) => {
    const dir = `${__dirname}/releases/${productName}/darwin`;

    const versionsDesc = fs.readdirSync(dir).filter((file) => {
        const filePath = path.join(dir, file);
        return fs.statSync(filePath).isDirectory();
    }).reverse();

    return versionsDesc[0];
};

let getBaseUrl = () => {
    if (process.env.NODE_ENV === "development") {
        return "http://localhost:3000";
    } else {
        return "http://thingsSDK.com";
    }
};

app.listen(process.env.PORT, () => {
    console.log(`Express server listening on port ${process.env.PORT}`);
});