fritzbox-api/examples/08_alarmLoop.mjs

Straightforward, lightweight and extendable Node.js library to communicate with FRITZ!Box devices

// Copyright (c) 2026, Thorsten A. Weintz. All rights reserved.
// Licensed under the MIT license. See LICENSE in the project root for license information.

import FritzBoxApi, { url, setCredentials } from './config.mjs';

/**
 * Writes a message to the console.
 */
const log = console.log;

/**
 * Initializes new instance of @see FritzBoxApi and sets options.
 */
const fritzBoxApi = new FritzBoxApi({ url });

/**
 * Sets the credentials used for authentication against the FRITZ!Box.
 */
setCredentials(fritzBoxApi);

/**
 * The device identifier for the call (e.g., phone number, extension, or device ID).
 */
const number = '**610';

/**
 * Indicates whether the alarm loop is active.
 */
let running = false;

/**
 * Delays execution for a given number of milliseconds.
 * 
 * @param {*} ms Delay in milliseconds.
 * @returns {Promise<void>}
 */
const sleep = (ms) => new Promise(r => setTimeout(r, ms));

/**
 * Continuously triggers calls to simulate an alarm.
 * 
 * @param {*} number Target device identifier.
 */
const alarmLoop = async (number) => {
    log('Alarm started');

    while (running) {
        try {
            await fritzBoxApi.hangup();

            await sleep(300);

            await fritzBoxApi.callDevice(number);

        } catch { }

        await sleep(10000);
    }

    log('Alarm stopped');
};

/**
 * Starts the alarm loop if not already running.
 * 
 * @param {*} number Target device identifier.
 * @returns {void}
 */
const startAlarm = (number) => {
    if (running) return;

    running = true;

    alarmLoop(number);
};

/**
 * Stops the alarm loop and hangs up any active call.
 */
const stopAlarm = () => {
    running = false;

    fritzBoxApi.hangup().catch(() => {});
};

/**
 * Handles process termination (Ctrl+C).
 */
process.on('SIGINT', () => {
    log('Shutting down...');

    stopAlarm();

    setTimeout(() => process.exit(0), 1000);
});

/**
 * Starts the alarm on script execution.
 */
startAlarm(number);