Function findFreePort

javascript/selenium-webdriver/net/portprober.js:53–70

* @param {string=} opt_host The bound host to test the port against. * Defaults to INADDR_ANY. * @return {!Promise } A promise that will resolve to a free port. If a * port cannot be found, the promise will be rejected.

(opt_host)

 */

function findFreePort(opt_host) {
  return new Promise((resolve, reject) => {
    const server = net.createServer()
    server.on('listening', function () {
      resolve(server.address().port)
      server.close()
    })
    server.on('error', (e) => {
      if (e.code === 'EADDRINUSE' || e.code === 'EACCES') {
        resolve('Unable to find a free port')
      } else {
        reject(e)
      }
    })
    // By providing 0 we let the operative system find an arbitrary port
    server.listen(0, opt_host)
  })
}

// PUBLIC API
module.exports = {