code: function onExit(exitCode) {
    console.log('Shutting down http-server...')
    httpServer.close(function(err) {
      if(err) console.warn('HTTP server close failed: %s', err)
      else console.log('HTTP server closed.')
    })
  
    if (!Swarm.host) {
      console.log('Swarm host not created yet...')
      return process.exit(exitCode)
    }
  
    console.log('Closing swarm host...')
    let forcedExit = setTimeout(function() {
      console.log('Swarm host close timeout, forcing exit.')
      process.exit(exitCode)
    }, 5000)
  
    Swarm.host.close(function() {
      console.log('Swarm host closed.')
      clearTimeout(forcedExit)
      process.exit(exitCode)
    })
  }
docs: /* eslint-disable no-process-exit