Naan and Paneer Makhani

    get-port
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    6.1.2 • Public • Published

    get-port

    Get an available TCP port.

    Install

    npm install get-port

    Usage

    import getPort from 'get-port';
    
    console.log(await getPort());
    //=> 51402

    Pass in a preferred port:

    import getPort from 'get-port';
    
    console.log(await getPort({port: 3000}));
    // Will use 3000 if available, otherwise fall back to a random port

    Pass in an array of preferred ports:

    import getPort from 'get-port';
    
    console.log(await getPort({port: [3000, 3001, 3002]}));
    // Will use any element in the preferred ports array if available, otherwise fall back to a random port

    Use the portNumbers() helper in case you need a port in a certain range:

    import getPort, {portNumbers} from 'get-port';
    
    console.log(await getPort({port: portNumbers(3000, 3100)}));
    // Will use any port from 3000 to 3100, otherwise fall back to a random port

    API

    getPort(options?)

    Returns a Promise for a port number.

    options

    Type: object

    port

    Type: number | Iterable<number>

    A preferred port or an iterable of preferred ports to use.

    exclude

    Type: Iterable<number>

    Ports that should not be returned.

    You could, for example, pass it the return value of the portNumbers() function.

    host

    Type: string

    The host on which port resolution should be performed. Can be either an IPv4 or IPv6 address.

    By default, it checks availability on all local addresses defined in OS network interfaces. If this option is set, it will only check the given host.

    portNumbers(from, to)

    Generate port numbers in the given range from...to.

    Returns an Iterable for port numbers in the given range.

    from

    Type: number

    The first port of the range. Must be in the range 1024...65535.

    to

    Type: number

    The last port of the range. Must be in the range 1024...65535 and must be greater than from.

    Beware

    There is a very tiny chance of a race condition if another process starts using the same port number as you in between the time you get the port number and you actually start using it.

    Race conditions in the same process are mitigated against by using a lightweight locking mechanism where a port will be held for a minimum of 15 seconds and a maximum of 30 seconds before being released again.

    Related


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    Install

    npm i get-port

    DownloadsWeekly Downloads

    5,406,827

    Version

    6.1.2

    License

    MIT

    Unpacked Size

    11.1 kB

    Total Files

    5

    Last publish

    Collaborators

    • sindresorhus