listening-on

Discover local and network interface addresses and print friendly URLs for your services.


Plain node.js alternative to running-at with reusable network interface discovery.

This package doesn't rely on execa and ip, hence more portable.

Installation

``bash


with npm

npm i listening-on

or with pnpm

pnpm i listening-on

or with yarn

yarn add listening-on
`

Usage Example

$3

Named import example:

`typescript
import express from 'express'
import { print } from 'listening-on'

const PORT = +process.env.PORT! || 3000
const app = express()

app.use(express.static('public'))

app.listen(PORT, () => {
print(PORT)
/* will print out below lines:
listening on http://127.0.0.1:8100 (lo)
listening on http://192.168.59.46:8100 (wlp3s0)
*/
})
`

commonjs compatible import example:

`typescript
import * as listeningOn from 'listening-on'

listeningOn.print(PORT)

// or simply use require
require('listening-on').print(PORT)
`

$3

`typescript
import { scan_host } from 'listening-on'

scan_host({
family: 'all',
onAddress: ({ host }) => {
// do something with the address
appendToCaddyFile(host)
},
})
`

Possible use cases:

- Print service URLs to the console for development.
- Generate upstream entries for a Caddyfile automatically.
- Feed bootstrap peers into a P2P network discovery list.
- Pre-populate environment configs or service discovery registries with your live IPs.

API Reference (TypeScript)

`typescript
export function print(port_or_options: number | PrintOptions): void

export function scan_host(options: ScanOptions): void

export type PrintOptions = {
port: number
// default http
protocol?: Protocol | string
// default IPv4
family?: Family | 'all'
}

export type Protocol = 'http' | 'https' | 'ws' | 'wss' | 'tcp' | 'udp'

export type Family = 'IPv4' | 'IPv6'

export type ScanOptions = {
// default IPv4
family?: Family | 'all'
onAddress: (address: {
/* interface name, e.g. lo, wlp3s0 /
name: string
/* ip address, e.g. 127.0.0.1, 192.168.59.46 /
host: string
/* ip family, e.g. IPv4, IPv6 /
family: Family
}) => void
}
``

License

This is free and open-source software (FOSS) with
BSD-2-Clause License