pair.js

const axios = require('axios');
const express = require('express');
const { v4: uuidv4 } = require('uuid');
const { register, listen } = require('push-receiver');

const app = express();
const port = 3000;
const server = app.listen(port);

var expoPushToken = null;
var steamAuthToken = null;

async function run() {

    console.log("Registering with FCM");
    const credentials = await register('976529667804');

    console.log("Fetching Expo Push Token");
    axios.post('https://exp.host/--/api/v2/push/getExpoPushToken', {
        deviceId: uuidv4(),
        experienceId: '@facepunch/RustCompanion',
        appId: 'com.facepunch.rust.companion',
        deviceToken: credentials.fcm.token,
        type: 'fcm',
        development: false,
    }).then(async (response) => {

        expoPushToken = response.data.data.expoPushToken;
        console.log("Received Expo Push Token: " + expoPushToken);

        // register callback
        app.get('/callback', (req, res) => {

            steamAuthToken = req.query.token;

            if(steamAuthToken){

                console.log("Steam Account Connected.");
                res.send('Steam Account successfully linked with rustplus-api. You can now close this window and go back to the console.');

                // register with Rust Companion API
                console.log("Registering with Rust Companion API");
                axios.post('https://companion-rust.facepunch.com:443/api/push/register', {
                    AuthToken: steamAuthToken,
                    DeviceId: 'rustplus-api',
                    PushKind: 0,
                    PushToken: expoPushToken,
                }).then((response) => {
                    console.log("Successfully registered with Rust Companion API.");
                    console.log("When you Pair with Servers or Smart Devices in game, notifications will appear here.");
                }).catch((error) => {
                    console.log("Failed to register with Rust Companion API");
                    console.log(error);
                });

            } else {
                res.send('token missing from request!');
            }

        });

        // ask user to login with steam
        console.log("Please open the following URL in your browser to link your Steam Account with rustplus-api.");
        console.log("https://companion-rust.facepunch.com/login?returnUrl=" + encodeURIComponent(`http://localhost:${port}/callback`));

        console.log("Listening for FCM Notifications");
        await listen(credentials, ({ notification, persistentId }) => {

            // parse notification body
            const body = JSON.parse(notification.data.body);

            // log notification body
            console.log(body);

        });

    }).catch((error) => {
        console.log("Failed to fetch Expo Push Token");
        console.log(error);
    });

}

process.on('SIGTERM', shutdown);
process.on('SIGINT', shutdown);

async function shutdown() {

    // unregister with Rust Companion API
    if(steamAuthToken){
        console.log("Unregistering from Rust Companion API");
        await axios.delete('https://companion-rust.facepunch.com:443/api/push/unregister', {
            data: {
                AuthToken: steamAuthToken,
                PushToken: expoPushToken,
                DeviceId: 'rustplus-api',
            },
        }).then((response) => {
            console.log("Successfully unregistered from Rust Companion API");
        }).catch((error) => {
            console.log(error);
        });
    }

    // stop http server
    server.close(() => {
        process.exit(0);
    });

}

run();