test(bitswap:testnet)

misc:
* test network client getting more than max
* test for find providers
* rename factory method
* local network
* misc test improvements
* test bitswap get block timeout
* test provider exists but cannot connect to peer
* test sending a message async over local network

exchange/bitswap/bitswap_test.go

+package bitswap
+
+import (
+	"testing"
+	"time"
+
+	context "github.com/jbenet/go-ipfs/Godeps/_workspace/src/code.google.com/p/go.net/context"
+
+	ds "github.com/jbenet/go-ipfs/Godeps/_workspace/src/github.com/jbenet/datastore.go"
+	bstore "github.com/jbenet/go-ipfs/blockstore"
+	exchange "github.com/jbenet/go-ipfs/exchange"
+	notifications "github.com/jbenet/go-ipfs/exchange/bitswap/notifications"
+	strategy "github.com/jbenet/go-ipfs/exchange/bitswap/strategy"
+	peer "github.com/jbenet/go-ipfs/peer"
+	testutil "github.com/jbenet/go-ipfs/util/testutil"
+)
+
+func TestGetBlockTimeout(t *testing.T) {
+
+	net := LocalNetwork()
+	rs := newRoutingServer()
+	ipfs := session(net, rs, []byte("peer id"))
+	ctx, _ := context.WithTimeout(context.Background(), time.Nanosecond)
+	block := testutil.NewBlockOrFail(t, "block")
+
+	_, err := ipfs.exchange.Block(ctx, block.Key())
+	if err != context.DeadlineExceeded {
+		t.Fatal("Expected DeadlineExceeded error")
+	}
+}
+
+func TestProviderForKeyButNetworkCannotFind(t *testing.T) {
+
+	net := LocalNetwork()
+	rs := newRoutingServer()
+	ipfs := session(net, rs, []byte("peer id"))
+	// ctx := context.Background()
+	ctx, _ := context.WithTimeout(context.Background(), time.Nanosecond)
+	block := testutil.NewBlockOrFail(t, "block")
+
+	rs.Announce(&peer.Peer{}, block.Key()) // but not on network
+
+	_, err := ipfs.exchange.Block(ctx, block.Key())
+	if err != context.DeadlineExceeded {
+		t.Fatal("Expected DeadlineExceeded error")
+	}
+}
+
+type ipfs struct {
+	peer       *peer.Peer
+	exchange   exchange.Interface
+	blockstore bstore.Blockstore
+}
+
+func session(net Network, rs RoutingServer, id peer.ID) ipfs {
+	p := &peer.Peer{}
+
+	adapter := net.Adapter(p)
+	htc := rs.Client(p)
+
+	blockstore := bstore.NewBlockstore(ds.NewMapDatastore())
+	bs := &bitswap{
+		blockstore:    blockstore,
+		notifications: notifications.New(),
+		strategy:      strategy.New(),
+		routing:       htc,
+		sender:        adapter,
+	}
+	adapter.SetDelegate(bs)
+	return ipfs{
+		peer:       p,
+		exchange:   bs,
+		blockstore: blockstore,
+	}
+}
+
+func TestSendToWantingPeer(t *testing.T) {
+	t.Log("Peer |w| tells me it wants file, but I don't have it")
+	t.Log("Then another peer |o| sends it to me")
+	t.Log("After receiving the file from |o|, I send it to the wanting peer |w|")
+}

exchange/bitswap/hash_table.go

+package bitswap
+
+import (
+	"errors"
+	"sync"
+
+	context "github.com/jbenet/go-ipfs/Godeps/_workspace/src/code.google.com/p/go.net/context"
+	peer "github.com/jbenet/go-ipfs/peer"
+	u "github.com/jbenet/go-ipfs/util"
+)
+
+type RoutingServer interface {
+	// TODO
+	Announce(*peer.Peer, u.Key) error
+
+	// TODO
+	Providers(u.Key) []*peer.Peer
+
+	// TODO
+	// Returns a Routing instance configured to query this hash table
+	Client(*peer.Peer) Routing
+}
+
+func newRoutingServer() RoutingServer {
+	return &hashTable{
+		m: make(map[u.Key]map[*peer.Peer]bool),
+	}
+}
+
+type hashTable struct {
+	lock sync.RWMutex
+	m    map[u.Key]map[*peer.Peer]bool
+}
+
+var TODO = errors.New("TODO")
+
+func (rs *hashTable) Announce(p *peer.Peer, k u.Key) error {
+	rs.lock.Lock()
+	defer rs.lock.Unlock()
+
+	_, ok := rs.m[k]
+	if !ok {
+		rs.m[k] = make(map[*peer.Peer]bool)
+	}
+	rs.m[k][p] = true
+	return nil
+}
+
+func (rs *hashTable) Providers(k u.Key) []*peer.Peer {
+	rs.lock.RLock()
+	defer rs.lock.RUnlock()
+	ret := make([]*peer.Peer, 0)
+	peerset, ok := rs.m[k]
+	if !ok {
+		return ret
+	}
+	for peer, _ := range peerset {
+		ret = append(ret, peer)
+	}
+	return ret
+}
+
+// TODO
+func (rs *hashTable) Client(p *peer.Peer) Routing {
+	return &routingClient{
+		peer:      p,
+		hashTable: rs,
+	}
+}
+
+type routingClient struct {
+	peer      *peer.Peer
+	hashTable RoutingServer
+}
+
+func (a *routingClient) FindProvidersAsync(ctx context.Context, k u.Key, max int) <-chan *peer.Peer {
+	out := make(chan *peer.Peer)
+	go func() {
+		defer close(out)
+		for i, p := range a.hashTable.Providers(k) {
+			if max <= i {
+				return
+			}
+			select {
+			case out <- p:
+			case <-ctx.Done():
+				return
+			}
+		}
+	}()
+	return out
+}
+
+func (a *routingClient) Provide(key u.Key) error {
+	return a.hashTable.Announce(a.peer, key)
+}

exchange/bitswap/hash_table_test.go

+package bitswap
+
+import (
+	"bytes"
+	"testing"
+
+	context "github.com/jbenet/go-ipfs/Godeps/_workspace/src/code.google.com/p/go.net/context"
+)
+import (
+	"github.com/jbenet/go-ipfs/peer"
+	u "github.com/jbenet/go-ipfs/util"
+)
+
+func TestKeyNotFound(t *testing.T) {
+
+	rs := func() RoutingServer {
+		// TODO fields
+		return &hashTable{}
+	}()
+	empty := rs.Providers(u.Key("not there"))
+	if len(empty) != 0 {
+		t.Fatal("should be empty")
+	}
+}
+
+func TestSetAndGet(t *testing.T) {
+	pid := peer.ID([]byte("the peer id"))
+	p := &peer.Peer{
+		ID: pid,
+	}
+	k := u.Key("42")
+	rs := newRoutingServer()
+	err := rs.Announce(p, k)
+	if err != nil {
+		t.Fatal(err)
+	}
+	providers := rs.Providers(k)
+	if len(providers) != 1 {
+		t.Fatal("should be one")
+	}
+	for _, elem := range providers {
+		if bytes.Equal(elem.ID, pid) {
+			return
+		}
+	}
+	t.Fatal("ID should have matched")
+}
+
+func TestClientFindProviders(t *testing.T) {
+	peer := &peer.Peer{
+		ID: []byte("42"),
+	}
+	rs := newRoutingServer()
+	client := rs.Client(peer)
+	k := u.Key("hello")
+	err := client.Provide(k)
+	if err != nil {
+		t.Fatal(err)
+	}
+	max := 100
+
+	providersFromHashTable := rs.Providers(k)
+
+	isInHT := false
+	for _, p := range providersFromHashTable {
+		if bytes.Equal(p.ID, peer.ID) {
+			isInHT = true
+		}
+	}
+	if !isInHT {
+		t.Fatal("Despite client providing key, peer wasn't in hash table as a provider")
+	}
+	providersFromClient := client.FindProvidersAsync(context.Background(), u.Key("hello"), max)
+	isInClient := false
+	for p := range providersFromClient {
+		if bytes.Equal(p.ID, peer.ID) {
+			isInClient = true
+		}
+	}
+	if !isInClient {
+		t.Fatal("Despite client providing key, client didn't receive peer when finding providers")
+	}
+}
+
+func TestClientOverMax(t *testing.T) {
+	rs := newRoutingServer()
+	k := u.Key("hello")
+	numProvidersForHelloKey := 100
+	for i := 0; i < numProvidersForHelloKey; i++ {
+		peer := &peer.Peer{
+			ID: []byte(string(i)),
+		}
+		err := rs.Announce(peer, k)
+		if err != nil {
+			t.Fatal(err)
+		}
+	}
+	providersFromHashTable := rs.Providers(k)
+	if len(providersFromHashTable) != numProvidersForHelloKey {
+		t.Log(1 == len(providersFromHashTable))
+		t.Fatal("not all providers were returned")
+	}
+
+	max := 10
+	client := rs.Client(&peer.Peer{ID: []byte("TODO")})
+	providersFromClient := client.FindProvidersAsync(context.Background(), k, max)
+	i := 0
+	for _ = range providersFromClient {
+		i++
+	}
+	if i != max {
+		t.Fatal("Too many providers returned")
+	}
+}
+
+// TODO does dht ensure won't receive self as a provider? probably not.
+func TestCanceledContext(t *testing.T) {
+	rs := newRoutingServer()
+	k := u.Key("hello")
+
+	t.Log("async'ly announce infinite stream of providers for key")
+	i := 0
+	go func() { // infinite stream
+		for {
+			peer := &peer.Peer{
+				ID: []byte(string(i)),
+			}
+			err := rs.Announce(peer, k)
+			if err != nil {
+				t.Fatal(err)
+			}
+			i++
+		}
+	}()
+
+	client := rs.Client(&peer.Peer{ID: []byte("peer id doesn't matter")})
+
+	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")
+	}
+}

exchange/bitswap/local_network.go

+package bitswap
+
+import (
+	"bytes"
+	"errors"
+
+	context "github.com/jbenet/go-ipfs/Godeps/_workspace/src/code.google.com/p/go.net/context"
+	bsmsg "github.com/jbenet/go-ipfs/exchange/bitswap/message"
+	bsnet "github.com/jbenet/go-ipfs/exchange/bitswap/network"
+	peer "github.com/jbenet/go-ipfs/peer"
+	"github.com/jbenet/go-ipfs/util"
+)
+
+type Network interface {
+	Adapter(*peer.Peer) bsnet.Adapter
+
+	SendMessage(
+		ctx context.Context,
+		from *peer.Peer,
+		to *peer.Peer,
+		message bsmsg.BitSwapMessage) error
+
+	SendRequest(
+		ctx context.Context,
+		from *peer.Peer,
+		to *peer.Peer,
+		message bsmsg.BitSwapMessage) (
+		incoming bsmsg.BitSwapMessage, err error)
+}
+
+// network impl
+
+func LocalNetwork() Network {
+	return &network{
+		clients: make(map[util.Key]bsnet.Receiver),
+	}
+}
+
+type network struct {
+	clients map[util.Key]bsnet.Receiver
+}
+
+func (n *network) Adapter(p *peer.Peer) bsnet.Adapter {
+	client := &networkClient{
+		local:   p,
+		network: n,
+	}
+	n.clients[p.Key()] = client
+	return client
+}
+
+// TODO should this be completely asynchronous?
+// TODO what does the network layer do with errors received from services?
+func (n *network) SendMessage(
+	ctx context.Context,
+	from *peer.Peer,
+	to *peer.Peer,
+	message bsmsg.BitSwapMessage) error {
+
+	receiver, ok := n.clients[to.Key()]
+	if !ok {
+		return errors.New("Cannot locate peer on network")
+	}
+
+	// nb: terminate the context since the context wouldn't actually be passed
+	// over the network in a real scenario
+
+	go n.deliver(receiver, from, message)
+
+	return nil
+}
+
+func (n *network) deliver(
+	r bsnet.Receiver, from *peer.Peer, message bsmsg.BitSwapMessage) error {
+	if message == nil || from == nil {
+		return errors.New("Invalid input")
+	}
+
+	nextPeer, nextMsg, err := r.ReceiveMessage(context.TODO(), from, message)
+	if err != nil {
+
+		// TODO should this error be returned across network boundary?
+
+		// TODO this raises an interesting question about network contract. How
+		// can the network be expected to behave under different failure
+		// conditions? What if peer is unreachable? Will we know if messages
+		// aren't delivered?
+
+		return err
+	}
+
+	if (nextPeer == nil && nextMsg != nil) || (nextMsg == nil && nextPeer != nil) {
+		return errors.New("Malformed client request")
+	}
+
+	if nextPeer == nil && nextMsg == nil {
+		return nil
+	}
+
+	nextReceiver, ok := n.clients[nextPeer.Key()]
+	if !ok {
+		return errors.New("Cannot locate peer on network")
+	}
+	go n.deliver(nextReceiver, nextPeer, nextMsg)
+	return nil
+}
+
+var NoResponse = errors.New("No response received from the receiver")
+
+// TODO
+func (n *network) SendRequest(
+	ctx context.Context,
+	from *peer.Peer,
+	to *peer.Peer,
+	message bsmsg.BitSwapMessage) (
+	incoming bsmsg.BitSwapMessage, err error) {
+
+	r, ok := n.clients[to.Key()]
+	if !ok {
+		return nil, errors.New("Cannot locate peer on network")
+	}
+	nextPeer, nextMsg, err := r.ReceiveMessage(context.TODO(), from, message)
+	if err != nil {
+		return nil, err
+		// TODO return nil, NoResponse
+	}
+
+	// TODO dedupe code
+	if (nextPeer == nil && nextMsg != nil) || (nextMsg == nil && nextPeer != nil) {
+		return nil, errors.New("Malformed client request")
+	}
+
+	// TODO dedupe code
+	if nextPeer == nil && nextMsg == nil {
+		return nil, nil
+	}
+
+	// TODO test when receiver doesn't immediately respond to the initiator of the request
+	if !bytes.Equal(nextPeer.ID, from.ID) {
+		go func() {
+			nextReceiver, ok := n.clients[nextPeer.Key()]
+			if !ok {
+				// TODO log the error?
+			}
+			n.deliver(nextReceiver, nextPeer, nextMsg)
+		}()
+		return nil, NoResponse
+	}
+	return nextMsg, nil
+}
+
+type networkClient struct {
+	local *peer.Peer
+	bsnet.Receiver
+	network Network
+}
+
+func (nc *networkClient) SendMessage(
+	ctx context.Context,
+	to *peer.Peer,
+	message bsmsg.BitSwapMessage) error {
+	return nc.network.SendMessage(ctx, nc.local, to, message)
+}
+
+func (nc *networkClient) SendRequest(
+	ctx context.Context,
+	to *peer.Peer,
+	message bsmsg.BitSwapMessage) (incoming bsmsg.BitSwapMessage, err error) {
+	return nc.network.SendRequest(ctx, nc.local, to, message)
+}
+
+func (nc *networkClient) SetDelegate(r bsnet.Receiver) {
+	nc.Receiver = r
+}

exchange/bitswap/local_network_test.go

+package bitswap
+
+import (
+	"sync"
+	"testing"
+
+	context "github.com/jbenet/go-ipfs/Godeps/_workspace/src/code.google.com/p/go.net/context"
+	bsmsg "github.com/jbenet/go-ipfs/exchange/bitswap/message"
+	bsnet "github.com/jbenet/go-ipfs/exchange/bitswap/network"
+	peer "github.com/jbenet/go-ipfs/peer"
+	testutil "github.com/jbenet/go-ipfs/util/testutil"
+)
+
+func TestSendRequestToCooperativePeer(t *testing.T) {
+	net := LocalNetwork()
+
+	idOfRecipient := []byte("recipient")
+
+	t.Log("Get two network adapters")
+
+	initiator := net.Adapter(&peer.Peer{ID: []byte("initiator")})
+	recipient := net.Adapter(&peer.Peer{ID: idOfRecipient})
+
+	expectedStr := "response from recipient"
+	recipient.SetDelegate(lambda(func(
+		ctx context.Context,
+		from *peer.Peer,
+		incoming bsmsg.BitSwapMessage) (
+		*peer.Peer, bsmsg.BitSwapMessage, error) {
+
+		t.Log("Recipient received a message from the network")
+
+		// TODO test contents of incoming message
+
+		m := bsmsg.New()
+		m.AppendBlock(testutil.NewBlockOrFail(t, expectedStr))
+
+		return from, m, nil
+	}))
+
+	t.Log("Build a message and send a synchronous request to recipient")
+
+	message := bsmsg.New()
+	message.AppendBlock(testutil.NewBlockOrFail(t, "data"))
+	response, err := initiator.SendRequest(
+		context.Background(), &peer.Peer{ID: idOfRecipient}, message)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	t.Log("Check the contents of the response from recipient")
+
+	for _, blockFromRecipient := range response.Blocks() {
+		if string(blockFromRecipient.Data) == expectedStr {
+			return
+		}
+	}
+	t.Fatal("Should have returned after finding expected block data")
+}
+
+func TestSendMessageAsyncButWaitForResponse(t *testing.T) {
+	net := LocalNetwork()
+	idOfResponder := []byte("responder")
+	waiter := net.Adapter(&peer.Peer{ID: []byte("waiter")})
+	responder := net.Adapter(&peer.Peer{ID: idOfResponder})
+
+	var wg sync.WaitGroup
+
+	wg.Add(1)
+
+	expectedStr := "received async"
+
+	responder.SetDelegate(lambda(func(
+		ctx context.Context,
+		fromWaiter *peer.Peer,
+		msgFromWaiter bsmsg.BitSwapMessage) (
+		*peer.Peer, bsmsg.BitSwapMessage, error) {
+
+		msgToWaiter := bsmsg.New()
+		msgToWaiter.AppendBlock(testutil.NewBlockOrFail(t, expectedStr))
+
+		return fromWaiter, msgToWaiter, nil
+	}))
+
+	waiter.SetDelegate(lambda(func(
+		ctx context.Context,
+		fromResponder *peer.Peer,
+		msgFromResponder bsmsg.BitSwapMessage) (
+		*peer.Peer, bsmsg.BitSwapMessage, error) {
+
+		// TODO assert that this came from the correct peer and that the message contents are as expected
+		ok := false
+		for _, b := range msgFromResponder.Blocks() {
+			if string(b.Data) == expectedStr {
+				wg.Done()
+				ok = true
+			}
+		}
+
+		if !ok {
+			t.Fatal("Message not received from the responder")
+
+		}
+		return nil, nil, nil
+	}))
+
+	messageSentAsync := bsmsg.New()
+	messageSentAsync.AppendBlock(testutil.NewBlockOrFail(t, "data"))
+	errSending := waiter.SendMessage(
+		context.Background(), &peer.Peer{ID: idOfResponder}, messageSentAsync)
+	if errSending != nil {
+		t.Fatal(errSending)
+	}
+
+	wg.Wait() // until waiter delegate function is executed
+}
+
+type receiverFunc func(ctx context.Context, p *peer.Peer,
+	incoming bsmsg.BitSwapMessage) (*peer.Peer, bsmsg.BitSwapMessage, error)
+
+// lambda returns a Receiver instance given a receiver function
+func lambda(f receiverFunc) bsnet.Receiver {
+	return &lambdaImpl{
+		f: f,
+	}
+}
+
+type lambdaImpl struct {
+	f func(ctx context.Context, p *peer.Peer,
+		incoming bsmsg.BitSwapMessage) (
+		*peer.Peer, bsmsg.BitSwapMessage, error)
+}
+
+func (lam *lambdaImpl) ReceiveMessage(ctx context.Context,
+	p *peer.Peer, incoming bsmsg.BitSwapMessage) (
+	*peer.Peer, bsmsg.BitSwapMessage, error) {
+	return lam.f(ctx, p, incoming)
+}

exchange/bitswap/strategy/strategy.go

@@ -51,6 +51,13 @@ func (s *strategist) Seed(int64) {
 }
 
 func (s *strategist) MessageReceived(p *peer.Peer, m bsmsg.BitSwapMessage) error {
+	// TODO find a more elegant way to handle this check
+	if p == nil {
+		return errors.New("Strategy received nil peer")
+	}
+	if m == nil {
+		return errors.New("Strategy received nil message")
+	}
 	l := s.ledger(p)
 	for _, key := range m.Wantlist() {
 		l.Wants(key)