index.js

const { program } = require('commander');
var pjson = require('./package.json');
const fs = require("fs");

function myParseInt(value, dummyPrevious) {
    const parsedValue = parseInt(value, 10);
    if (isNaN(parsedValue)) throw new Error('Invalid argument: Must be a number.');
    return parsedValue;
}

program.option("-p, --port <number>", "start http server with a specific port number", myParseInt, 21889);
program.option("-c, --connect <id>", "connect to an existing obs server instead of starting a new one");
program.option("-v, --version", "output the version number");
program.option("-vo, --osn-version", "output the osn version number");
program.option("--obs <path>", "the path to obs lib, if at a non-standard location");
program.option("--data <path>", "the path to data folder, if at a non-standard location");
program.parse();
var clio = program.opts();

if (clio.version) {
    console.log(pjson.version);
    return;
}

if (clio.osnVersion) {
    console.log(pjson.osnVersion);
    return;
}

console.log("Received CLI arguments: " + JSON.stringify(clio));

const _ = require("lodash");
const express = require("express");
const bodyParser = require('body-parser');
const obs = require("./obs");
const volmeter = require("./volmeter");

// create express
const app = express();
const port = clio.port;
let server;

// handle sigint/shutdown
if (process.platform === "win32") {
    const rl = require("readline").createInterface({
        input: process.stdin,
        output: process.stdout
    });

    rl.on("SIGINT", function () {
        process.emit("SIGINT");
    });
}

process.on("SIGINT", function () {
    console.log("Recieved SIGINT");
    shutdown(0);
});

process.on("SIGTERM", function () {
    console.log("Recieved SIGTERM");
    shutdown(0);
});

function shutdown(code) {
    console.log("Start graceful shutdown: code " + code);
    try {
        obs.release();
        server.close();
    } catch { }
    console.log("Exiting...");
    process.exit(code);
}

app.use(bodyParser.json({ extended: true }));

app.use(function (req, res, next) {
    res.setHeader('Content-Type', 'application/json');
    next();
});

function DO_OK(res) {
    res.status(200).send(JSON.stringify({ status: "ok" }));
}

function DO_JSON(res, body) {
    res.status(200).send(JSON.stringify(body));
}

// routes
app.get("/", (req, res) => {
    const routes = _(app._router.stack)
        .filter(s => !_.isEmpty(s.route))
        .map(s => ({ route: s.route.path, methods: s.route.methods }))
        .toArray();
    DO_JSON(res, routes);
});

app.get("/status", (req, res) => {
    DO_JSON(res, obs.getStatistics());
});

app.get("/audio/speakers", (req, res) => {
    DO_JSON(res, volmeter.getSpeakers());
});

app.get("/audio/microphones", (req, res) => {
    DO_JSON(res, volmeter.getMicrophones());
});

app.get("/settings/:settingKey", (req, res) => {
    let small = true;
    if (_.isString(req.query.detailed) && req.query.detailed.toLowerCase() === "true") {
        small = false;
    }
    DO_JSON(res, obs.getSettingsCategory(req.params.settingKey, small));
});

app.post("/settings/:settingKey", (req, res) => {
    obs.updateSettingsCategory(req.params.settingKey, req.body);
    DO_OK(res);
});

app.post("/recording/start", (req, res, next) => {
    obs.recordingStart(req.body).then(s => DO_OK(res)).catch(next);
});

app.post("/recording/stop", (req, res, next) => {
    obs.recordingStop().then(s => DO_OK(res)).catch(next);
});

app.post("/shutdown", (req, res) => {
    shutdown(0);
});

app.use(function (err, req, res, next) {
    console.error(err.stack)
    if (!!err.message) {
        res.status(500).send(JSON.stringify({ status: "error", message: err.message /*, stack: err.stack*/ }));
    } else {
        res.status(500).send(JSON.stringify({ status: "error", message: err }));
    }
});

// startup
try {
    obs.init(clio.connect, clio.obs, clio.data);
    server = app.listen(port, "localhost", () => {
        console.log(`Listening at http://localhost:${port}`);
    });
    volmeter.createVolmeterServer(server);
} catch (e) {
    console.log(e.message || e);
    shutdown(1);
}