func TestClientOverMax(t *testing.T) {
	rs := NewServer()
	k := key.Key("hello")
	numProvidersForHelloKey := 100
	for i := 0; i < numProvidersForHelloKey; i++ {
		pi := testutil.RandIdentityOrFatal(t)
		err := rs.Client(pi).Provide(context.Background(), k)
		if err != nil {
			t.Fatal(err)
		}
	}

	max := 10
	pi := testutil.RandIdentityOrFatal(t)
	client := rs.Client(pi)

	providersFromClient := client.FindProvidersAsync(context.Background(), k, max)
	i := 0
	for _ = range providersFromClient {
		i++
	}
	if i != max {
		t.Fatal("Too many providers returned")
	}
}
Exemple #2
0
func TestRoutingResolve(t *testing.T) {
	d := mockrouting.NewServer().Client(testutil.RandIdentityOrFatal(t))

	resolver := NewRoutingResolver(d)
	publisher := NewRoutingPublisher(d)

	privk, pubk, err := testutil.RandTestKeyPair(512)
	if err != nil {
		t.Fatal(err)
	}

	h := path.FromString("/ipfs/QmZULkCELmmk5XNfCgTnCyFgAVxBRBXyDHGGMVoLFLiXEN")
	err = publisher.Publish(context.Background(), privk, h)
	if err != nil {
		t.Fatal(err)
	}

	pubkb, err := pubk.Bytes()
	if err != nil {
		t.Fatal(err)
	}

	pkhash := u.Hash(pubkb)
	res, err := resolver.Resolve(context.Background(), key.Key(pkhash).Pretty())
	if err != nil {
		t.Fatal(err)
	}

	if res != h {
		t.Fatal("Got back incorrect value.")
	}
}
Exemple #3
0
func TestAddLink(t *testing.T) {
	ds := mdtest.Mock()
	fishnode := &dag.Node{
		Data: []byte("fishcakes!"),
	}

	fk, err := ds.Add(fishnode)
	if err != nil {
		t.Fatal(err)
	}

	nd := new(dag.Node)
	nnode, err := addLink(context.Background(), ds, nd, "fish", fishnode)
	if err != nil {
		t.Fatal(err)
	}

	fnprime, err := nnode.GetLinkedNode(context.Background(), ds, "fish")
	if err != nil {
		t.Fatal(err)
	}

	fnpkey, err := fnprime.Key()
	if err != nil {
		t.Fatal(err)
	}

	if fnpkey != fk {
		t.Fatal("wrong child node found!")
	}
}
func TestClientFindProviders(t *testing.T) {
	pi := testutil.RandIdentityOrFatal(t)
	rs := NewServer()
	client := rs.Client(pi)

	k := key.Key("hello")
	err := client.Provide(context.Background(), k)
	if err != nil {
		t.Fatal(err)
	}

	// This is bad... but simulating networks is hard
	time.Sleep(time.Millisecond * 300)
	max := 100

	providersFromClient := client.FindProvidersAsync(context.Background(), key.Key("hello"), max)
	isInClient := false
	for pi := range providersFromClient {
		if pi.ID == pi.ID {
			isInClient = true
		}
	}
	if !isInClient {
		t.Fatal("Despite client providing key, client didn't receive peer when finding providers")
	}
}
// TODO does dht ensure won't receive self as a provider? probably not.
func TestCanceledContext(t *testing.T) {
	rs := NewServer()
	k := key.Key("hello")

	// avoid leaking goroutine, without using the context to signal
	// (we want the goroutine to keep trying to publish on a
	// cancelled context until we've tested it doesnt do anything.)
	done := make(chan struct{})
	defer func() { done <- struct{}{} }()

	t.Log("async'ly announce infinite stream of providers for key")
	i := 0
	go func() { // infinite stream
		for {
			select {
			case <-done:
				t.Log("exiting async worker")
				return
			default:
			}

			pi, err := testutil.RandIdentity()
			if err != nil {
				t.Error(err)
			}
			err = rs.Client(pi).Provide(context.Background(), k)
			if err != nil {
				t.Error(err)
			}
			i++
		}
	}()

	local := testutil.RandIdentityOrFatal(t)
	client := rs.Client(local)

	t.Log("warning: max is finite so this test is non-deterministic")
	t.Log("context cancellation could simply take lower priority")
	t.Log("and result in receiving the max number of results")
	max := 1000

	t.Log("cancel the context before consuming")
	ctx, cancelFunc := context.WithCancel(context.Background())
	cancelFunc()
	providers := client.FindProvidersAsync(ctx, k, max)

	numProvidersReturned := 0
	for _ = range providers {
		numProvidersReturned++
	}
	t.Log(numProvidersReturned)

	if numProvidersReturned == max {
		t.Fatal("Context cancel had no effect")
	}
}
Exemple #6
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func ExampleEventLogger() {
	{
		log := EventLogger(nil)
		e := log.EventBegin(context.Background(), "dial")
		e.Done()
	}
	{
		log := EventLogger(nil)
		e := log.EventBegin(context.Background(), "dial")
		_ = e.Close() // implements io.Closer for convenience
	}
}
func TestMultiWrite(t *testing.T) {
	dserv, pins := getMockDagServ(t)
	_, n := getNode(t, dserv, 0, pins)

	ctx, cancel := context.WithCancel(context.Background())
	defer cancel()

	dagmod, err := NewDagModifier(ctx, n, dserv, pins, sizeSplitterGen(512))
	if err != nil {
		t.Fatal(err)
	}

	data := make([]byte, 4000)
	u.NewTimeSeededRand().Read(data)

	for i := 0; i < len(data); i++ {
		n, err := dagmod.WriteAt(data[i:i+1], int64(i))
		if err != nil {
			t.Fatal(err)
		}
		if n != 1 {
			t.Fatal("Somehow wrote the wrong number of bytes! (n != 1)")
		}

		size, err := dagmod.Size()
		if err != nil {
			t.Fatal(err)
		}

		if size != int64(i+1) {
			t.Fatal("Size was reported incorrectly")
		}
	}
	nd, err := dagmod.GetNode()
	if err != nil {
		t.Fatal(err)
	}

	read, err := uio.NewDagReader(context.Background(), nd, dserv)
	if err != nil {
		t.Fatal(err)
	}
	rbuf, err := ioutil.ReadAll(read)
	if err != nil {
		t.Fatal(err)
	}

	err = arrComp(rbuf, data)
	if err != nil {
		t.Fatal(err)
	}
}
Exemple #8
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func TestGetBlocks(t *testing.T) {
	store := bstore()
	ex := Exchange(store)
	g := blocksutil.NewBlockGenerator()

	expected := g.Blocks(2)

	for _, b := range expected {
		if err := ex.HasBlock(b); err != nil {
			t.Fail()
		}
	}

	request := func() []key.Key {
		var ks []key.Key

		for _, b := range expected {
			ks = append(ks, b.Key())
		}
		return ks
	}()

	received, err := ex.GetBlocks(context.Background(), request)
	if err != nil {
		t.Fatal(err)
	}

	var count int
	for _ = range received {
		count++
	}
	if len(expected) != count {
		t.Fail()
	}
}
Exemple #9
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func TestConnHandler(t *testing.T) {
	// t.Skip("skipping for another test")
	t.Parallel()

	ctx := context.Background()
	swarms := makeSwarms(ctx, t, 5)

	gotconn := make(chan struct{}, 10)
	swarms[0].SetConnHandler(func(conn *Conn) {
		gotconn <- struct{}{}
	})

	connectSwarms(t, ctx, swarms)

	<-time.After(time.Millisecond)
	// should've gotten 5 by now.

	swarms[0].SetConnHandler(nil)

	expect := 4
	for i := 0; i < expect; i++ {
		select {
		case <-time.After(time.Second):
			t.Fatal("failed to get connections")
		case <-gotconn:
		}
	}

	select {
	case <-gotconn:
		t.Fatalf("should have connected to %d swarms", expect)
	default:
	}
}
Exemple #10
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func TestFindPeer(t *testing.T) {
	// t.Skip("skipping test to debug another")
	if testing.Short() {
		t.SkipNow()
	}

	ctx := context.Background()

	_, peers, dhts := setupDHTS(ctx, 4, t)
	defer func() {
		for i := 0; i < 4; i++ {
			dhts[i].Close()
			dhts[i].host.Close()
		}
	}()

	connect(t, ctx, dhts[0], dhts[1])
	connect(t, ctx, dhts[1], dhts[2])
	connect(t, ctx, dhts[1], dhts[3])

	ctxT, _ := context.WithTimeout(ctx, time.Second)
	p, err := dhts[0].FindPeer(ctxT, peers[2])
	if err != nil {
		t.Fatal(err)
	}

	if p.ID == "" {
		t.Fatal("Failed to find peer.")
	}

	if p.ID != peers[2] {
		t.Fatal("Didnt find expected peer.")
	}
}
func BenchmarkDagmodWrite(b *testing.B) {
	b.StopTimer()
	dserv, pins := getMockDagServ(b)
	_, n := getNode(b, dserv, 0, pins)
	ctx, cancel := context.WithCancel(context.Background())
	defer cancel()

	wrsize := 4096

	dagmod, err := NewDagModifier(ctx, n, dserv, pins, sizeSplitterGen(512))
	if err != nil {
		b.Fatal(err)
	}

	buf := make([]byte, b.N*wrsize)
	u.NewTimeSeededRand().Read(buf)
	b.StartTimer()
	b.SetBytes(int64(wrsize))
	for i := 0; i < b.N; i++ {
		n, err := dagmod.Write(buf[i*wrsize : (i+1)*wrsize])
		if err != nil {
			b.Fatal(err)
		}
		if n != wrsize {
			b.Fatal("Wrote bad size")
		}
	}
}
Exemple #12
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func TestBuilderConsistency(t *testing.T) {
	nbytes := 100000
	buf := new(bytes.Buffer)
	io.CopyN(buf, u.NewTimeSeededRand(), int64(nbytes))
	should := dup(buf.Bytes())
	dagserv := mdtest.Mock()
	nd, err := buildTestDag(dagserv, chunk.DefaultSplitter(buf))
	if err != nil {
		t.Fatal(err)
	}
	r, err := uio.NewDagReader(context.Background(), nd, dagserv)
	if err != nil {
		t.Fatal(err)
	}

	out, err := ioutil.ReadAll(r)
	if err != nil {
		t.Fatal(err)
	}

	err = arrComp(out, should)
	if err != nil {
		t.Fatal(err)
	}
}
Exemple #13
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func TestSeekEndSingleBlockFile(t *testing.T) {
	nbytes := int64(100)
	should := make([]byte, nbytes)
	u.NewTimeSeededRand().Read(should)

	read := bytes.NewReader(should)
	ds := mdtest.Mock()
	nd, err := buildTestDag(ds, chunk.NewSizeSplitter(read, 5000))
	if err != nil {
		t.Fatal(err)
	}

	rs, err := uio.NewDagReader(context.Background(), nd, ds)
	if err != nil {
		t.Fatal(err)
	}

	seeked, err := rs.Seek(0, os.SEEK_END)
	if err != nil {
		t.Fatal(err)
	}
	if seeked != nbytes {
		t.Fatal("Failed to seek to end")
	}
}
Exemple #14
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func testInsert(t *testing.T, e *Editor, path, data string, create bool, experr string) {
	child := &dag.Node{Data: []byte(data)}
	ck, err := e.ds.Add(child)
	if err != nil {
		t.Fatal(err)
	}

	var c func() *dag.Node
	if create {
		c = func() *dag.Node {
			return &dag.Node{}
		}
	}

	err = e.InsertNodeAtPath(context.Background(), path, child, c)
	if experr != "" {
		var got string
		if err != nil {
			got = err.Error()
		}
		if got != experr {
			t.Fatalf("expected '%s' but got '%s'", experr, got)
		}
		return
	}

	if err != nil {
		t.Fatal(err)
	}

	assertNodeAtPath(t, e.ds, e.root, path, ck)
}
Exemple #15
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func TestDeadlineFractionCancel(t *testing.T) {

	ctx1, cancel1 := context.WithTimeout(context.Background(), 10*time.Millisecond)
	ctx2, cancel2 := WithDeadlineFraction(ctx1, 0.5)

	select {
	case <-ctx1.Done():
		t.Fatal("ctx1 ended too early")
	case <-ctx2.Done():
		t.Fatal("ctx2 ended too early")
	default:
	}

	cancel2()

	select {
	case <-ctx1.Done():
		t.Fatal("ctx1 should NOT be cancelled")
	case <-ctx2.Done():
	default:
		t.Fatal("ctx2 should be cancelled")
	}

	cancel1()

	select {
	case <-ctx1.Done():
	case <-ctx2.Done():
	default:
		t.Fatal("ctx1 should be cancelled")
	}

}
Exemple #16
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func TestDialBadAddrs(t *testing.T) {

	m := func(s string) ma.Multiaddr {
		maddr, err := ma.NewMultiaddr(s)
		if err != nil {
			t.Fatal(err)
		}
		return maddr
	}

	ctx := context.Background()
	s := makeSwarms(ctx, t, 1)[0]

	test := func(a ma.Multiaddr) {
		p := testutil.RandPeerIDFatal(t)
		s.peers.AddAddr(p, a, peer.PermanentAddrTTL)
		if _, err := s.Dial(ctx, p); err == nil {
			t.Error("swarm should not dial: %s", m)
		}
	}

	test(m("/ip6/fe80::1"))                // link local
	test(m("/ip6/fe80::100"))              // link local
	test(m("/ip4/127.0.0.1/udp/1234/utp")) // utp
}
Exemple #17
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func TestFilterBounds(t *testing.T) {
	ctx := context.Background()
	swarms := makeSwarms(ctx, t, 2)

	conns := make(chan struct{}, 8)
	swarms[0].SetConnHandler(func(conn *Conn) {
		conns <- struct{}{}
	})

	// Address that we wont be dialing from
	_, block, err := net.ParseCIDR("192.0.0.1/8")
	if err != nil {
		t.Fatal(err)
	}

	// set filter on both sides, shouldnt matter
	swarms[1].Filters.AddDialFilter(block)
	swarms[0].Filters.AddDialFilter(block)

	connectSwarms(t, ctx, swarms)

	select {
	case <-time.After(time.Second):
		t.Fatal("should have gotten connection")
	case <-conns:
		t.Log("got connect")
	}
}
Exemple #18
0
func TestAddrBlocking(t *testing.T) {
	ctx := context.Background()
	swarms := makeSwarms(ctx, t, 2)

	swarms[0].SetConnHandler(func(conn *Conn) {
		t.Fatal("no connections should happen!")
	})

	_, block, err := net.ParseCIDR("127.0.0.1/8")
	if err != nil {
		t.Fatal(err)
	}

	swarms[1].Filters.AddDialFilter(block)

	swarms[1].peers.AddAddr(swarms[0].LocalPeer(), swarms[0].ListenAddresses()[0], peer.PermanentAddrTTL)
	_, err = swarms[1].Dial(ctx, swarms[0].LocalPeer())
	if err == nil {
		t.Fatal("dial should have failed")
	}

	swarms[0].peers.AddAddr(swarms[1].LocalPeer(), swarms[1].ListenAddresses()[0], peer.PermanentAddrTTL)
	_, err = swarms[0].Dial(ctx, swarms[1].LocalPeer())
	if err == nil {
		t.Fatal("dial should have failed")
	}
}
Exemple #19
0
func TestIndirectBlocks(t *testing.T) {
	splitter := chunk.SizeSplitterGen(512)
	nbytes := 1024 * 1024
	buf := make([]byte, nbytes)
	u.NewTimeSeededRand().Read(buf)

	read := bytes.NewReader(buf)

	ds := mdtest.Mock()
	dag, err := buildTestDag(ds, splitter(read))
	if err != nil {
		t.Fatal(err)
	}

	reader, err := uio.NewDagReader(context.Background(), dag, ds)
	if err != nil {
		t.Fatal(err)
	}

	out, err := ioutil.ReadAll(reader)
	if err != nil {
		t.Fatal(err)
	}

	if !bytes.Equal(out, buf) {
		t.Fatal("Not equal!")
	}
}
Exemple #20
0
func addDefaultAssets(out io.Writer, repoRoot string) error {
	ctx, cancel := context.WithCancel(context.Background())
	defer cancel()

	r, err := fsrepo.Open(repoRoot)
	if err != nil { // NB: repo is owned by the node
		return err
	}

	nd, err := core.NewNode(ctx, &core.BuildCfg{Repo: r})
	if err != nil {
		return err
	}
	defer nd.Close()

	dkey, err := assets.SeedInitDocs(nd)
	if err != nil {
		return fmt.Errorf("init: seeding init docs failed: %s", err)
	}
	log.Debugf("init: seeded init docs %s", dkey)

	if _, err = fmt.Fprintf(out, "to get started, enter:\n"); err != nil {
		return err
	}

	_, err = fmt.Fprintf(out, "\n\tipfs cat /ipfs/%s/readme\n\n", dkey)
	return err
}
Exemple #21
0
func testFileConsistency(t *testing.T, bs chunk.SplitterGen, nbytes int) {
	should := make([]byte, nbytes)
	u.NewTimeSeededRand().Read(should)

	read := bytes.NewReader(should)
	ds := mdtest.Mock()
	nd, err := buildTestDag(ds, bs(read))
	if err != nil {
		t.Fatal(err)
	}

	r, err := uio.NewDagReader(context.Background(), nd, ds)
	if err != nil {
		t.Fatal(err)
	}

	out, err := ioutil.ReadAll(r)
	if err != nil {
		t.Fatal(err)
	}

	err = arrComp(out, should)
	if err != nil {
		t.Fatal(err)
	}
}
Exemple #22
0
func TestSimultOpen(t *testing.T) {
	// t.Skip("skipping for another test")
	t.Parallel()

	ctx := context.Background()
	swarms := makeSwarms(ctx, t, 2)

	// connect everyone
	{
		var wg sync.WaitGroup
		connect := func(s *Swarm, dst peer.ID, addr ma.Multiaddr) {
			// copy for other peer
			log.Debugf("TestSimultOpen: connecting: %s --> %s (%s)", s.local, dst, addr)
			s.peers.AddAddr(dst, addr, peer.PermanentAddrTTL)
			if _, err := s.Dial(ctx, dst); err != nil {
				t.Fatal("error swarm dialing to peer", err)
			}
			wg.Done()
		}

		log.Info("Connecting swarms simultaneously.")
		wg.Add(2)
		go connect(swarms[0], swarms[1].local, swarms[1].ListenAddresses()[0])
		go connect(swarms[1], swarms[0].local, swarms[0].ListenAddresses()[0])
		wg.Wait()
	}

	for _, s := range swarms {
		s.Close()
	}
}
func RunSupernodePutRecordGetRecord(conf testutil.LatencyConfig) error {
	ctx, cancel := context.WithCancel(context.Background())
	defer cancel()

	servers, clients, err := InitializeSupernodeNetwork(ctx, 2, 2, conf)
	if err != nil {
		return err
	}
	for _, n := range append(servers, clients...) {
		defer n.Close()
	}

	putter := clients[0]
	getter := clients[1]

	k := key.Key("key")
	note := []byte("a note from putter")

	if err := putter.Routing.PutValue(ctx, k, note); err != nil {
		return fmt.Errorf("failed to put value: %s", err)
	}

	received, err := getter.Routing.GetValue(ctx, k)
	if err != nil {
		return fmt.Errorf("failed to get value: %s", err)
	}

	if 0 != bytes.Compare(note, received) {
		return errors.New("record doesn't match")
	}
	return nil
}
Exemple #24
0
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,
	})

	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 TestDagTruncate(t *testing.T) {
	dserv, pins := getMockDagServ(t)
	b, n := getNode(t, dserv, 50000, pins)
	ctx, cancel := context.WithCancel(context.Background())
	defer cancel()

	dagmod, err := NewDagModifier(ctx, n, dserv, pins, sizeSplitterGen(512))
	if err != nil {
		t.Fatal(err)
	}

	err = dagmod.Truncate(12345)
	if err != nil {
		t.Fatal(err)
	}

	_, err = dagmod.Seek(0, os.SEEK_SET)
	if err != nil {
		t.Fatal(err)
	}

	out, err := ioutil.ReadAll(dagmod)
	if err != nil {
		t.Fatal(err)
	}

	if err = arrComp(out, b[:12345]); err != nil {
		t.Fatal(err)
	}
}
Exemple #26
0
func TestGetBlocksSequential(t *testing.T) {
	var servs = Mocks(4)
	for _, s := range servs {
		defer s.Close()
	}
	bg := blocksutil.NewBlockGenerator()
	blks := bg.Blocks(50)

	var keys []key.Key
	for _, blk := range blks {
		keys = append(keys, blk.Key())
		servs[0].AddBlock(blk)
	}

	t.Log("one instance at a time, get blocks concurrently")

	for i := 1; i < len(servs); i++ {
		ctx, cancel := context.WithTimeout(context.Background(), time.Second*50)
		defer cancel()
		out := servs[i].GetBlocks(ctx, keys)
		gotten := make(map[key.Key]*blocks.Block)
		for blk := range out {
			if _, ok := gotten[blk.Key()]; ok {
				t.Fatal("Got duplicate block!")
			}
			gotten[blk.Key()] = blk
		}
		if len(gotten) != len(blks) {
			t.Fatalf("Didnt get enough blocks back: %d/%d", len(gotten), len(blks))
		}
	}
}
func printDag(nd *mdag.Node, ds mdag.DAGService, indent int) {
	pbd, err := ft.FromBytes(nd.Data)
	if err != nil {
		panic(err)
	}

	for i := 0; i < indent; i++ {
		fmt.Print(" ")
	}
	fmt.Printf("{size = %d, type = %s, children = %d", pbd.GetFilesize(), pbd.GetType().String(), len(pbd.GetBlocksizes()))
	if len(nd.Links) > 0 {
		fmt.Println()
	}
	for _, lnk := range nd.Links {
		child, err := lnk.GetNode(context.Background(), ds)
		if err != nil {
			panic(err)
		}
		printDag(child, ds, indent+1)
	}
	if len(nd.Links) > 0 {
		for i := 0; i < indent; i++ {
			fmt.Print(" ")
		}
	}
	fmt.Println("}")
}
Exemple #28
0
func TestBalancedDag(t *testing.T) {
	ds := mdtest.Mock()
	buf := make([]byte, 10000)
	u.NewTimeSeededRand().Read(buf)
	r := bytes.NewReader(buf)

	nd, err := BuildDagFromReader(ds, chunk.DefaultSplitter(r), nil)
	if err != nil {
		t.Fatal(err)
	}

	dr, err := uio.NewDagReader(context.Background(), nd, ds)
	if err != nil {
		t.Fatal(err)
	}

	out, err := ioutil.ReadAll(dr)
	if err != nil {
		t.Fatal(err)
	}

	if !bytes.Equal(out, buf) {
		t.Fatal("bad read")
	}
}
func TestValidAfter(t *testing.T) {

	pi := testutil.RandIdentityOrFatal(t)
	var key = key.Key("mock key")
	var ctx = context.Background()
	conf := DelayConfig{
		ValueVisibility: delay.Fixed(1 * time.Hour),
		Query:           delay.Fixed(0),
	}

	rs := NewServerWithDelay(conf)

	rs.Client(pi).Provide(ctx, key)

	var providers []peer.PeerInfo
	providers, err := rs.Client(pi).FindProviders(ctx, key)
	if err != nil {
		t.Fatal(err)
	}
	if len(providers) > 0 {
		t.Fail()
	}

	conf.ValueVisibility.Set(0)
	providers, err = rs.Client(pi).FindProviders(ctx, key)
	if err != nil {
		t.Fatal(err)
	}
	t.Log("providers", providers)
	if len(providers) != 1 {
		t.Fail()
	}
}
Exemple #30
0
func TestGetBlockFromPeerAfterPeerAnnounces(t *testing.T) {

	net := tn.VirtualNetwork(mockrouting.NewServer(), delay.Fixed(kNetworkDelay))
	block := blocks.NewBlock([]byte("block"))
	g := NewTestSessionGenerator(net)
	defer g.Close()

	peers := g.Instances(2)
	hasBlock := peers[0]
	defer hasBlock.Exchange.Close()

	if err := hasBlock.Exchange.HasBlock(block); err != nil {
		t.Fatal(err)
	}

	wantsBlock := peers[1]
	defer wantsBlock.Exchange.Close()

	ctx, cancel := context.WithTimeout(context.Background(), time.Second)
	defer cancel()
	received, err := wantsBlock.Exchange.GetBlock(ctx, block.Key())
	if err != nil {
		t.Log(err)
		t.Fatal("Expected to succeed")
	}

	if !bytes.Equal(block.Data, received.Data) {
		t.Fatal("Data doesn't match")
	}
}