mild refactor of bitswap

bitswap.go

@@ -4,6 +4,7 @@ package bitswap
 
 import (
 	"errors"
+	"fmt"
 	"math"
 	"sync"
 	"time"
@@ -324,47 +325,31 @@ func (bs *Bitswap) sendWantlistToProviders(ctx context.Context, entries []wantli
 }
 
 // TODO(brian): handle errors
-func (bs *Bitswap) ReceiveMessage(ctx context.Context, p peer.ID, incoming bsmsg.BitSwapMessage) (
-	peer.ID, bsmsg.BitSwapMessage) {
+func (bs *Bitswap) ReceiveMessage(ctx context.Context, p peer.ID, incoming bsmsg.BitSwapMessage) error {
 	defer log.EventBegin(ctx, "receiveMessage", p, incoming).Done()
 
-	if p == "" {
-		log.Debug("Received message from nil peer!")
-		// TODO propagate the error upward
-		return "", nil
-	}
-	if incoming == nil {
-		log.Debug("Got nil bitswap message!")
-		// TODO propagate the error upward
-		return "", nil
-	}
-
 	// This call records changes to wantlists, blocks received,
 	// and number of bytes transfered.
 	bs.engine.MessageReceived(p, incoming)
 	// TODO: this is bad, and could be easily abused.
 	// Should only track *useful* messages in ledger
 
+	var keys []u.Key
 	for _, block := range incoming.Blocks() {
 		bs.blocksRecvd++
 		if has, err := bs.blockstore.Has(block.Key()); err == nil && has {
 			bs.dupBlocksRecvd++
 		}
+		log.Debugf("got block %s from %s", block, p)
 		hasBlockCtx, cancel := context.WithTimeout(ctx, hasBlockTimeout)
 		if err := bs.HasBlock(hasBlockCtx, block); err != nil {
-			log.Debug(err)
+			return fmt.Errorf("ReceiveMessage HasBlock error: %s", err)
 		}
 		cancel()
-	}
-
-	var keys []u.Key
-	for _, block := range incoming.Blocks() {
 		keys = append(keys, block.Key())
 	}
-	bs.cancelBlocks(ctx, keys)
 
-	// TODO: consider changing this function to not return anything
-	return "", nil
+	return bs.cancelBlocks(ctx, keys)
 }
 
 // Connected/Disconnected warns bitswap about peer connections
@@ -384,21 +369,24 @@ func (bs *Bitswap) PeerDisconnected(p peer.ID) {
 	bs.engine.PeerDisconnected(p)
 }
 
-func (bs *Bitswap) cancelBlocks(ctx context.Context, bkeys []u.Key) {
+func (bs *Bitswap) cancelBlocks(ctx context.Context, bkeys []u.Key) error {
 	if len(bkeys) < 1 {
-		return
+		return nil
 	}
 	message := bsmsg.New()
 	message.SetFull(false)
 	for _, k := range bkeys {
+		log.Debug("cancel block: %s", k)
 		message.Cancel(k)
 	}
 	for _, p := range bs.engine.Peers() {
 		err := bs.send(ctx, p, message)
 		if err != nil {
 			log.Debugf("Error sending message: %s", err)
+			return err
 		}
 	}
+	return nil
 }
 
 func (bs *Bitswap) wantNewBlocks(ctx context.Context, bkeys []u.Key) {

network/interface.go

@@ -19,12 +19,6 @@ type BitSwapNetwork interface {
 		peer.ID,
 		bsmsg.BitSwapMessage) error
 
-	// SendRequest sends a BitSwap message to a peer and waits for a response.
-	SendRequest(
-		context.Context,
-		peer.ID,
-		bsmsg.BitSwapMessage) (incoming bsmsg.BitSwapMessage, err error)
-
 	// SetDelegate registers the Reciver to handle messages received from the
 	// network.
 	SetDelegate(Receiver)
@@ -35,8 +29,9 @@ type BitSwapNetwork interface {
 // Implement Receiver to receive messages from the BitSwapNetwork
 type Receiver interface {
 	ReceiveMessage(
-		ctx context.Context, sender peer.ID, incoming bsmsg.BitSwapMessage) (
-		destination peer.ID, outgoing bsmsg.BitSwapMessage)
+		ctx context.Context,
+		sender peer.ID,
+		incoming bsmsg.BitSwapMessage) error
 
 	ReceiveError(error)
 

testnet/network_test.go

@@ -14,57 +14,6 @@ import (
 	testutil "github.com/ipfs/go-ipfs/util/testutil"
 )
 
-func TestSendRequestToCooperativePeer(t *testing.T) {
-	net := VirtualNetwork(mockrouting.NewServer(), delay.Fixed(0))
-
-	recipientPeer := testutil.RandIdentityOrFatal(t)
-
-	t.Log("Get two network adapters")
-
-	initiator := net.Adapter(testutil.RandIdentityOrFatal(t))
-	recipient := net.Adapter(recipientPeer)
-
-	expectedStr := "response from recipient"
-	recipient.SetDelegate(lambda(func(
-		ctx context.Context,
-		from peer.ID,
-		incoming bsmsg.BitSwapMessage) (
-		peer.ID, bsmsg.BitSwapMessage) {
-
-		t.Log("Recipient received a message from the network")
-
-		// TODO test contents of incoming message
-
-		m := bsmsg.New()
-		m.AddBlock(blocks.NewBlock([]byte(expectedStr)))
-
-		return from, m
-	}))
-
-	t.Log("Build a message and send a synchronous request to recipient")
-
-	message := bsmsg.New()
-	message.AddBlock(blocks.NewBlock([]byte("data")))
-	response, err := initiator.SendRequest(
-		context.Background(), recipientPeer.ID(), message)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	t.Log("Check the contents of the response from recipient")
-
-	if response == nil {
-		t.Fatal("Should have received a response")
-	}
-
-	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 := VirtualNetwork(mockrouting.NewServer(), delay.Fixed(0))
 	responderPeer := testutil.RandIdentityOrFatal(t)
@@ -80,20 +29,19 @@ func TestSendMessageAsyncButWaitForResponse(t *testing.T) {
 	responder.SetDelegate(lambda(func(
 		ctx context.Context,
 		fromWaiter peer.ID,
-		msgFromWaiter bsmsg.BitSwapMessage) (
-		peer.ID, bsmsg.BitSwapMessage) {
+		msgFromWaiter bsmsg.BitSwapMessage) error {
 
 		msgToWaiter := bsmsg.New()
 		msgToWaiter.AddBlock(blocks.NewBlock([]byte(expectedStr)))
+		waiter.SendMessage(ctx, fromWaiter, msgToWaiter)
 
-		return fromWaiter, msgToWaiter
+		return nil
 	}))
 
 	waiter.SetDelegate(lambda(func(
 		ctx context.Context,
 		fromResponder peer.ID,
-		msgFromResponder bsmsg.BitSwapMessage) (
-		peer.ID, bsmsg.BitSwapMessage) {
+		msgFromResponder bsmsg.BitSwapMessage) error {
 
 		// TODO assert that this came from the correct peer and that the message contents are as expected
 		ok := false
@@ -108,7 +56,7 @@ func TestSendMessageAsyncButWaitForResponse(t *testing.T) {
 			t.Fatal("Message not received from the responder")
 
 		}
-		return "", nil
+		return nil
 	}))
 
 	messageSentAsync := bsmsg.New()
@@ -123,7 +71,7 @@ func TestSendMessageAsyncButWaitForResponse(t *testing.T) {
 }
 
 type receiverFunc func(ctx context.Context, p peer.ID,
-	incoming bsmsg.BitSwapMessage) (peer.ID, bsmsg.BitSwapMessage)
+	incoming bsmsg.BitSwapMessage) error
 
 // lambda returns a Receiver instance given a receiver function
 func lambda(f receiverFunc) bsnet.Receiver {
@@ -133,13 +81,11 @@ func lambda(f receiverFunc) bsnet.Receiver {
 }
 
 type lambdaImpl struct {
-	f func(ctx context.Context, p peer.ID, incoming bsmsg.BitSwapMessage) (
-		peer.ID, bsmsg.BitSwapMessage)
+	f func(ctx context.Context, p peer.ID, incoming bsmsg.BitSwapMessage) error
 }
 
 func (lam *lambdaImpl) ReceiveMessage(ctx context.Context,
-	p peer.ID, incoming bsmsg.BitSwapMessage) (
-	peer.ID, bsmsg.BitSwapMessage) {
+	p peer.ID, incoming bsmsg.BitSwapMessage) error {
 	return lam.f(ctx, p, incoming)
 }
 

testnet/virtual.go

@@ -72,61 +72,7 @@ func (n *network) deliver(
 
 	n.delay.Wait()
 
-	nextPeer, nextMsg := r.ReceiveMessage(context.TODO(), from, message)
-
-	if (nextPeer == "" && nextMsg != nil) || (nextMsg == nil && nextPeer != "") {
-		return errors.New("Malformed client request")
-	}
-
-	if nextPeer == "" && nextMsg == nil { // no response to send
-		return nil
-	}
-
-	nextReceiver, ok := n.clients[nextPeer]
-	if !ok {
-		return errors.New("Cannot locate peer on network")
-	}
-	go n.deliver(nextReceiver, nextPeer, nextMsg)
-	return nil
-}
-
-// TODO
-func (n *network) SendRequest(
-	ctx context.Context,
-	from peer.ID,
-	to peer.ID,
-	message bsmsg.BitSwapMessage) (
-	incoming bsmsg.BitSwapMessage, err error) {
-
-	r, ok := n.clients[to]
-	if !ok {
-		return nil, errors.New("Cannot locate peer on network")
-	}
-	nextPeer, nextMsg := r.ReceiveMessage(context.TODO(), from, message)
-
-	// TODO dedupe code
-	if (nextPeer == "" && nextMsg != nil) || (nextMsg == nil && nextPeer != "") {
-		r.ReceiveError(errors.New("Malformed client request"))
-		return nil, nil
-	}
-
-	// TODO dedupe code
-	if nextPeer == "" && nextMsg == nil {
-		return nil, nil
-	}
-
-	// TODO test when receiver doesn't immediately respond to the initiator of the request
-	if nextPeer != from {
-		go func() {
-			nextReceiver, ok := n.clients[nextPeer]
-			if !ok {
-				// TODO log the error?
-			}
-			n.deliver(nextReceiver, nextPeer, nextMsg)
-		}()
-		return nil, nil
-	}
-	return nextMsg, nil
+	return r.ReceiveMessage(context.TODO(), from, message)
 }
 
 type networkClient struct {
@@ -143,13 +89,6 @@ func (nc *networkClient) SendMessage(
 	return nc.network.SendMessage(ctx, nc.local, to, message)
 }
 
-func (nc *networkClient) SendRequest(
-	ctx context.Context,
-	to peer.ID,
-	message bsmsg.BitSwapMessage) (incoming bsmsg.BitSwapMessage, err error) {
-	return nc.network.SendRequest(ctx, nc.local, to, message)
-}
-
 // FindProvidersAsync returns a channel of providers for the given key
 func (nc *networkClient) FindProvidersAsync(ctx context.Context, k util.Key, max int) <-chan peer.ID {