const pidFromPort = require('pid-from-port');

(async () => {
    try {
        console.log(await pidFromPort(8080));
        //=> 1337

        const pids = await pidFromPort.all([8080, 22]);

        console.log(pids.get(8080));
        //=> 1337

        console.log(pids.get(22));
        //=> 12345
    } catch (err) {
        console.log(err);
        //=> 'Couldn't find a process with port `8080`'
    }
})();