func runFileCattingWorker(ctx context.Context, n *core.IpfsNode) error {
	conf, err := config.Init(ioutil.Discard, *nBitsForKeypair)
	if err != nil {
		return err
	}

	r := &repo.Mock{
		D: ds2.CloserWrap(syncds.MutexWrap(datastore.NewMapDatastore())),
		C: *conf,
	}
	dummy, err := core.NewNode(ctx, &core.BuildCfg{
		Repo: r,
	})
	if err != nil {
		return err
	}

	errs := make(chan error)

	go func() {
		defer dummy.Close()
		var i int64 = 1
		for {
			buf := new(bytes.Buffer)
			if err := random.WritePseudoRandomBytes(sizeOfIthFile(i), buf, *seed); err != nil {
				errs <- err
			}
			// add to a dummy node to discover the key
			k, err := coreunix.Add(dummy, bytes.NewReader(buf.Bytes()))
			if err != nil {
				errs <- err
			}
			e := elog.EventBegin(ctx, "cat", logging.LoggableF(func() map[string]interface{} {
				return map[string]interface{}{
					"key":       k,
					"localPeer": n.Identity,
				}
			}))
			if r, err := coreunix.Cat(ctx, n, k); err != nil {
				e.Done()
				log.Printf("failed to cat file. seed: %d #%d key: %s err: %s", *seed, i, k, err)
			} else {
				log.Println("found file", "seed", *seed, "#", i, "key", k, "size", unit.Information(sizeOfIthFile(i)))
				io.Copy(ioutil.Discard, r)
				e.Done()
				log.Println("catted file", "seed", *seed, "#", i, "key", k, "size", unit.Information(sizeOfIthFile(i)))
				i++
			}
			time.Sleep(time.Second)
		}
	}()

	err = <-errs
	if err != nil {
		log.Fatal(err)
	}

	return nil
}

func InitializeSupernodeNetwork(
	ctx context.Context,
	numServers, numClients int,
	conf testutil.LatencyConfig) ([]*core.IpfsNode, []*core.IpfsNode, error) {

	// create network
	mn := mocknet.New(ctx)

	mn.SetLinkDefaults(mocknet.LinkOptions{
		Latency:   conf.NetworkLatency,
		Bandwidth: math.MaxInt32,
	})

	routingDatastore := ds2.CloserWrap(syncds.MutexWrap(datastore.NewMapDatastore()))
	var servers []*core.IpfsNode
	for i := 0; i < numServers; i++ {
		bootstrap, err := core.NewNode(ctx, &core.BuildCfg{
			Online:  true,
			Host:    mock.MockHostOption(mn),
			Routing: corerouting.SupernodeServer(routingDatastore),
		})
		if err != nil {
			return nil, nil, err
		}
		servers = append(servers, bootstrap)
	}

	var bootstrapInfos []pstore.PeerInfo
	for _, n := range servers {
		info := n.Peerstore.PeerInfo(n.PeerHost.ID())
		bootstrapInfos = append(bootstrapInfos, info)
	}

	var clients []*core.IpfsNode
	for i := 0; i < numClients; i++ {
		n, err := core.NewNode(ctx, &core.BuildCfg{
			Online:  true,
			Host:    mock.MockHostOption(mn),
			Routing: corerouting.SupernodeClient(bootstrapInfos...),
		})
		if err != nil {
			return nil, nil, err
		}
		clients = append(clients, n)
	}
	mn.LinkAll()

	bcfg := core.BootstrapConfigWithPeers(bootstrapInfos)
	for _, n := range clients {
		if err := n.Bootstrap(bcfg); err != nil {
			return nil, nil, err
		}
	}
	return servers, clients, nil
}

func MockCmdsCtx() (commands.Context, error) {
	// Generate Identity
	ident, err := testutil.RandIdentity()
	if err != nil {
		return commands.Context{}, err
	}
	p := ident.ID()

	conf := config.Config{
		Identity: config.Identity{
			PeerID: p.String(),
		},
	}

	r := &repo.Mock{
		D: ds2.CloserWrap(syncds.MutexWrap(datastore.NewMapDatastore())),
		C: conf,
	}

	node, err := core.NewNode(context.Background(), &core.BuildCfg{
		Repo: r,
	})
	if err != nil {
		return commands.Context{}, err
	}

	return commands.Context{
		Online:     true,
		ConfigRoot: "/tmp/.mockipfsconfig",
		LoadConfig: func(path string) (*config.Config, error) {
			return &conf, nil
		},
		ConstructNode: func() (*core.IpfsNode, error) {
			return node, nil
		},
	}, nil
}

func ThreadSafeCloserMapDatastore() ds2.ThreadSafeDatastoreCloser {
	return ds2.CloserWrap(syncds.MutexWrap(datastore.NewMapDatastore()))
}