dnssd-advertise

A well-behaved Bonjour/DNS-SD service advertiser for Node.js, designed for long-running processes.

- Aims to be compliant with RFC 6762 and RFC 6763
- Handles network interface changes, socket recovery, and re-announcements for long-running processes
- Supports dual-stack IPv4 and IPv6 service announcement with NIC-scoped responses
- Single dependency (dns-message is bundled)

Quick Reference

``javascript
import { advertise } from 'dnssd-advertise';

const stop = advertise({
name: 'My Service',
type: 'http',
protocol: 'tcp',
port: 3000,
});

process.on('exit', () => {
stop();
});
`

$3

When a conflict is detected during probing, as per the specification, the name or hostname of your service may be altered:

- When the name conflicts a 4-character hex ID is appended (e.g. My Service (B0A1)
- When the hostname conflicts a number is appended to it (e.g. my-hostname-2)

When a conflict is detected during announcing, the probing phase restarts with the same conflict resolution.

API Reference

$3

Starts advertising a DNS-SD service on all available network interfaces.

Returns a function that, when called, stops advertising and sends goodbye packets to remove the service from the network.
Stopping the advertiser is, while preferred, optional as per the mDNS specification.

#### Options

| Option | Type | Description |
| ---------- | -------------------------- | ------------------------------------------------------------------ |
| name | string | Instance/display name of the service (e.g., "Living Room Speaker") |
| type | string | Service type without protocol (e.g., "http", "ssh", "airplay") |
| protocol | 'tcp' \| 'udp' | Protocol used by the service |
| port | number | Port the service is listening on |
| hostname | string | Hostname to advertise (defaults to system hostname) |
| subtypes | string[] | Optional list of subtypes |
| txt | Record | Optional service metadata as key-value pairs |
| ttl | number` | TTL for DNS records in seconds (defaults to 250s) |