service-discovery-lib v1.0.3

Service Discovery Library

A lightweight Node.js library for discovering Genelec speakers that use PoE (Power over Ethernet) via mDNS (Multicast DNS).

Overview

This library provides an easy-to-use API for discovering Genelec speakers and other mDNS-enabled devices on your local network. It allows querying specific service types, parsing mDNS messages, filtering unique devices, and customizing network settings.

With the introduction of search_mdns_servicesmv1, you can now use an async/await approach for better control over your discovery process.

Features

✅ mDNS Service Discovery: Find Genelec speakers (or similar devices) on your network.
✅ Async/Await Support: New in v1! search_mdns_servicesmv1 allows async discovery.
✅ DNS Message Parsing: Supports PTR, SRV, TXT, and A records from mDNS responses.
✅ Dynamic Timeout: Configurable timeout (default 5000ms) to control search duration.
✅ Unique Device Tracking: Uses a Map to filter out duplicate discoveries.
✅ Network Interface Selection: Allows specifying a network interface for multicast traffic.
✅ Error Handling & Validations: Checks callback types, validates timeout values, and improves logging.
✅ Modular & Extendable: Easy to integrate into Node.js projects.

Installation

Install via npm:

npm install service-discovery-lib

For local development, see Local Testing.

Usage

v1: New Async Approach (search_mdns_servicesmv1)

The new version (search_mdns_servicesmv1) allows you to await the discovery results after the timeout period.

const { search_mdns_servicesmv1, list_interfaces } = require('service-discovery-lib');

(async () => {
    console.log('Available network interfaces:');
    list_interfaces().forEach((iface) => {
        console.log(`${iface.name}: ${iface.address} (${iface.family})`);
    });

    const options = {
        timeout: 5000, // Search duration in milliseconds
        service_query: '_genelec_poE._tcp', // Service query for Genelec speakers
        interface: 'YOUR_LOCAL_INTERFACE_IP', // (Optional) Specify a network interface
        on_service_found: (service) => {
            console.log('Genelec Speaker Found:', service);
        }
    };

    try {
        console.log('Starting Genelec Speaker Discovery...');
        const uniqueSpeakers = await search_mdns_servicesmv1(options);
        console.log('Discovery Complete. Unique Speakers Found:', uniqueSpeakers);
    } catch (error) {
        console.error('Error during mDNS search:', error);
    }
})();

✅ Advantages of v1 (search_mdns_servicesmv1):

• Fully asynchronous (uses await).
• Returns a Promise with the unique service list after the timeout.
• Avoids callback nesting (cleaner and easier to use).
• Safer error handling and better logging.

v0: Previous Callback-Based Method (search_mdns_services)

The older version (search_mdns_services) relies on callbacks instead of async/await.

const { search_mdns_services } = require('service-discovery-lib');

const options = {
    timeout: 5000,
    service_query: '_genelec_poE._tcp',
    interface: 'YOUR_LOCAL_INTERFACE_IP',
    on_service_found: (service) => {
        console.log('Genelec Speaker Found:', service);
    },
    on_search_complete: (uniqueServices) => {
        console.log('Discovery Finished. Unique Speakers:', uniqueServices);
    }
};

// Start discovery (without async/await)
search_mdns_services(options);

⚠️ Limitations of v0 (search_mdns_services):

• No await support (must rely on callbacks).
• Immediate function execution (does not return a Promise).
• Callback-based approach can be less readable in complex workflows.

API Comparison: v0 vs v1

🚀 Recommendation: Use search_mdns_servicesmv1 for a modern, async workflow.

Customization

Local Testing

For local development:

1. In Your Library Directory

Run:

npm link

2. In Your Test Project Directory

Navigate to your test project and link the library:

npm link service-discovery-lib

Then create a test file (test.js) and run:

node test.js

Contributing

We welcome feature requests, bug reports, and contributions!
Feel free to submit a Pull Request (PR) or open an issue.

Contact

📧 For support, contact truehearteam@example.com.

Disclaimer

This library is intended for discovering Genelec speakers (or similar PoE devices) via mDNS on a local network.
Ensure multicast traffic is enabled and your devices respond to mDNS queries.

What’s New in v1?

✅ Now supports async/await for a smoother workflow!
✅ Better error handling and structured logging.
✅ Automatically filters out duplicates using a Map.
✅ Easy to integrate into modern JavaScript projects.

🚀 Upgrade to search_mdns_servicesmv1 today!