Description


Find free port synchronously, useful when you need to get the port directly without callback.

Like config webpack-dev-server with port automatically.

``javascript
module.exports = {
...
output: '...',
devServer: {
...
port: "a free port"
}
};
`

Installation


`
npm install find-free-port-sync --save-dev
`

Options

start

type: number | default: 1

Start of range to find, should be greater than 0

end

type: number | default: 65534

End of range to find, should be less than 65535

num

type: number | default: 1

Number of ports to find, relates to the return value
- When num === 1, return a free random port if found, null if not
- When num > 1, return an array of free [port] orderly if found, empty array [] if not

ip


type: string | default: 0.0.0.0|127.0.0.1

It will scan local adress by default, specify an ip here

port

type: number | default: null

If port is defined, it will return whether the port is free around start end ip option




Examples


Find a free port for local address
`javascript
let findFreePort = require('find-free-port-sync');

let port = findFreePort();
`
Find 10 free ports between 10000 and 30000 for 192.168.1.1
`javascript
let findFreePort = require('find-free-port-sync');

let port = findFreePort({
start: 10000,
end: 30000,
num: 10,
ip: '192.168.1.1'
});
`
Check if a port is free
`javascript
let findFreePort = require('find-free-port-sync');

let portIsOk = findFreePort({
port: 12345
});
``