pick-port

Get an available TCP or UDP port for the given IP address.

Usage

const pickPort = require('pick-port');

pickPort()
	.then(port =>
	{
		console.log(port);
	});

Optionally, provide the TCP/IP protocol family type, IP address and/or port:

pickPort({ type: 'tcp', ip: '10.10.10.1', port: 8000 })
	.then(port =>
	{
		console.log(port);
	})
	.catch((error) =>
	{
		console.log(error);
	});

API

pickPort([options])

Returns a Promise.

Resolves with the free port number on success or throws if error or no free ports in the given range are available.

options

Type: Object

options.type

TCP/IP family type. Possible values for this parameter are 'udp' and 'tcp'.

• Type: String.
• Default value: 'udp'.

options.port

Specific port to be checked or 0 to specify that any free port can be taken.

• Type: Number.
• Default value: 0.

options.range

The port range for which a free port is requested. If specified, only ports in the given range are considered.

• Type: Object.
• Default value: undefined.

options.range.min

The minimum port number in the range.

• Type: Number

options.range.max

The maximum port number in the range.

• Type: Number.

options.ip

The IP address for which a free port is requested. IPv4 and IPv6 addressing is supported.

• Type: String.
• Default value: '127.0.0.1'.

options.reserveTimeout

Timeout in seconds, during which a returned free port will be internally reserved and prevented of being returned on a future call before the timeout has elapsed.

This provides the application using this library with the required time to bind the free port before it is given again on a future call.

• Type: Number.
• Default value: 5.