code: function join() {
    // import all in lib/js/, called only when the modules are needed
    lib_js = requireDir(path.join(__dirname, 'js'))
    log.debug(`import js lib from client.js`)
    const IOPORT = process.env.IOPORT || 6466
    log.info(`Starting socketIO client for js at ${IOPORT}`)
    client = socketIOClient(`http://localhost:${IOPORT}`)
    client.emit('join', ioid)
    client.on('disconnect', client.disconnect)
    client.on('take', handle)
    return client
  }
docs: /* istanbul ignore next