func (dht *IpfsDHT) handleFindPeer(ctx context.Context, p peer.ID, pmes *pb.Message) (*pb.Message, error) {
defer log.EventBegin(ctx, "handleFindPeer", p).Done()
resp := pb.NewMessage(pmes.GetType(), "", pmes.GetClusterLevel())
var closest []peer.ID
// if looking for self... special case where we send it on CloserPeers.
if peer.ID(pmes.GetKey()) == dht.self {
closest = []peer.ID{dht.self}
} else {
closest = dht.betterPeersToQuery(pmes, p, CloserPeerCount)
}
if closest == nil {
log.Infof("%s handleFindPeer %s: could not find anything.", dht.self, p)
return resp, nil
}
var withAddresses []peer.PeerInfo
closestinfos := peer.PeerInfos(dht.peerstore, closest)
for _, pi := range closestinfos {
if len(pi.Addrs) > 0 {
withAddresses = append(withAddresses, pi)
log.Debugf("handleFindPeer: sending back '%s'", pi.ID)
}
}
resp.CloserPeers = pb.PeerInfosToPBPeers(dht.host.Network(), withAddresses)
return resp, nil
}
func (dht *IpfsDHT) handleNewMessage(s inet.Stream) {
defer s.Close()
ctx := dht.Context()
cr := ctxio.NewReader(ctx, s) // ok to use. we defer close stream in this func
cw := ctxio.NewWriter(ctx, s) // ok to use. we defer close stream in this func
r := ggio.NewDelimitedReader(cr, inet.MessageSizeMax)
w := ggio.NewDelimitedWriter(cw)
mPeer := s.Conn().RemotePeer()
// receive msg
pmes := new(pb.Message)
if err := r.ReadMsg(pmes); err != nil {
log.Debugf("Error unmarshaling data: %s", err)
return
}
// update the peer (on valid msgs only)
dht.updateFromMessage(ctx, mPeer, pmes)
// get handler for this msg type.
handler := dht.handlerForMsgType(pmes.GetType())
if handler == nil {
log.Debug("got back nil handler from handlerForMsgType")
return
}
// dispatch handler.
rpmes, err := handler(ctx, mPeer, pmes)
if err != nil {
log.Debugf("handle message error: %s", err)
return
}
// if nil response, return it before serializing
if rpmes == nil {
log.Debug("Got back nil response from request.")
return
}
// send out response msg
if err := w.WriteMsg(rpmes); err != nil {
log.Debugf("send response error: %s", err)
return
}
return
}
// SendMessage sends message to each remote sequentially (randomized order),
// stopping after the first successful response. If all fail, returns the last
// error.
func (px *standard) SendMessage(ctx context.Context, m *dhtpb.Message) error {
var err error
var numSuccesses int
for _, remote := range sortedByKey(px.remoteIDs, m.GetKey()) {
if err = px.sendMessage(ctx, m, remote); err != nil { // careful don't re-declare err!
continue
}
numSuccesses++
switch m.GetType() {
case dhtpb.Message_ADD_PROVIDER, dhtpb.Message_PUT_VALUE:
if numSuccesses < replicationFactor {
continue
}
}
return nil // success
}
return err // NB: returns the last error
}
func (dht *IpfsDHT) handleGetProviders(ctx context.Context, p peer.ID, pmes *pb.Message) (*pb.Message, error) {
lm := make(lgbl.DeferredMap)
lm["peer"] = func() interface{} { return p.Pretty() }
defer log.EventBegin(ctx, "handleGetProviders", lm).Done()
resp := pb.NewMessage(pmes.GetType(), pmes.GetKey(), pmes.GetClusterLevel())
key := key.Key(pmes.GetKey())
lm["key"] = func() interface{} { return key.Pretty() }
// debug logging niceness.
reqDesc := fmt.Sprintf("%s handleGetProviders(%s, %s): ", dht.self, p, key)
log.Debugf("%s begin", reqDesc)
defer log.Debugf("%s end", reqDesc)
// check if we have this value, to add ourselves as provider.
has, err := dht.datastore.Has(key.DsKey())
if err != nil && err != ds.ErrNotFound {
log.Debugf("unexpected datastore error: %v\n", err)
has = false
}
// setup providers
providers := dht.providers.GetProviders(ctx, key)
if has {
providers = append(providers, dht.self)
log.Debugf("%s have the value. added self as provider", reqDesc)
}
if providers != nil && len(providers) > 0 {
infos := peer.PeerInfos(dht.peerstore, providers)
resp.ProviderPeers = pb.PeerInfosToPBPeers(dht.host.Network(), infos)
log.Debugf("%s have %d providers: %s", reqDesc, len(providers), infos)
}
// Also send closer peers.
closer := dht.betterPeersToQuery(pmes, p, CloserPeerCount)
if closer != nil {
infos := peer.PeerInfos(dht.peerstore, closer)
resp.CloserPeers = pb.PeerInfosToPBPeers(dht.host.Network(), infos)
log.Debugf("%s have %d closer peers: %s", reqDesc, len(closer), infos)
}
return resp, nil
}
// If less than K nodes are in the entire network, it should fail when we make
// a GET rpc and nobody has the value
func TestLessThanKResponses(t *testing.T) {
// t.Skip("skipping test to debug another")
// t.Skip("skipping test because it makes a lot of output")
ctx := context.Background()
mn, err := mocknet.FullMeshConnected(ctx, 6)
if err != nil {
t.Fatal(err)
}
hosts := mn.Hosts()
tsds := dssync.MutexWrap(ds.NewMapDatastore())
d := NewDHT(ctx, hosts[0], tsds)
for i := 1; i < 5; i++ {
d.Update(ctx, hosts[i].ID())
}
// Reply with random peers to every message
for _, host := range hosts {
host := host // shadow loop var
host.SetStreamHandler(ProtocolDHT, func(s inet.Stream) {
defer s.Close()
pbr := ggio.NewDelimitedReader(s, inet.MessageSizeMax)
pbw := ggio.NewDelimitedWriter(s)
pmes := new(pb.Message)
if err := pbr.ReadMsg(pmes); err != nil {
panic(err)
}
switch pmes.GetType() {
case pb.Message_GET_VALUE:
pi := host.Peerstore().PeerInfo(hosts[1].ID())
resp := &pb.Message{
Type: pmes.Type,
CloserPeers: pb.PeerInfosToPBPeers(d.host.Network(), []peer.PeerInfo{pi}),
}
if err := pbw.WriteMsg(resp); err != nil {
panic(err)
}
default:
panic("Shouldnt recieve this.")
}
})
}
ctx, _ = context.WithTimeout(ctx, time.Second*30)
if _, err := d.GetValue(ctx, key.Key("hello")); err != nil {
switch err {
case routing.ErrNotFound:
//Success!
return
case u.ErrTimeout:
t.Fatal("Should not have gotten timeout!")
default:
t.Fatalf("Got unexpected error: %s", err)
}
}
t.Fatal("Expected to recieve an error.")
}
func TestNotFound(t *testing.T) {
// t.Skip("skipping test to debug another")
if testing.Short() {
t.SkipNow()
}
ctx := context.Background()
mn, err := mocknet.FullMeshConnected(ctx, 16)
if err != nil {
t.Fatal(err)
}
hosts := mn.Hosts()
tsds := dssync.MutexWrap(ds.NewMapDatastore())
d := NewDHT(ctx, hosts[0], tsds)
for _, p := range hosts {
d.Update(ctx, p.ID())
}
// Reply with random peers to every message
for _, host := range hosts {
host := host // shadow loop var
host.SetStreamHandler(ProtocolDHT, func(s inet.Stream) {
defer s.Close()
pbr := ggio.NewDelimitedReader(s, inet.MessageSizeMax)
pbw := ggio.NewDelimitedWriter(s)
pmes := new(pb.Message)
if err := pbr.ReadMsg(pmes); err != nil {
panic(err)
}
switch pmes.GetType() {
case pb.Message_GET_VALUE:
resp := &pb.Message{Type: pmes.Type}
ps := []peer.PeerInfo{}
for i := 0; i < 7; i++ {
p := hosts[rand.Intn(len(hosts))].ID()
pi := host.Peerstore().PeerInfo(p)
ps = append(ps, pi)
}
resp.CloserPeers = pb.PeerInfosToPBPeers(d.host.Network(), ps)
if err := pbw.WriteMsg(resp); err != nil {
panic(err)
}
default:
panic("Shouldnt recieve this.")
}
})
}
// long timeout to ensure timing is not at play.
ctx, _ = context.WithTimeout(ctx, time.Second*20)
v, err := d.GetValue(ctx, key.Key("hello"))
log.Debugf("get value got %v", v)
if err != nil {
if merr, ok := err.(u.MultiErr); ok && len(merr) > 0 {
err = merr[0]
}
switch err {
case routing.ErrNotFound:
//Success!
return
case u.ErrTimeout:
t.Fatal("Should not have gotten timeout!")
default:
t.Fatalf("Got unexpected error: %s", err)
}
}
t.Fatal("Expected to recieve an error.")
}
func (dht *IpfsDHT) handleGetValue(ctx context.Context, p peer.ID, pmes *pb.Message) (*pb.Message, error) {
defer log.EventBegin(ctx, "handleGetValue", p).Done()
log.Debugf("%s handleGetValue for key: %s", dht.self, pmes.GetKey())
// setup response
resp := pb.NewMessage(pmes.GetType(), pmes.GetKey(), pmes.GetClusterLevel())
// first, is there even a key?
k := pmes.GetKey()
if k == "" {
return nil, errors.New("handleGetValue but no key was provided")
// TODO: send back an error response? could be bad, but the other node's hanging.
}
// let's first check if we have the value locally.
log.Debugf("%s handleGetValue looking into ds", dht.self)
dskey := key.Key(k).DsKey()
iVal, err := dht.datastore.Get(dskey)
log.Debugf("%s handleGetValue looking into ds GOT %v", dht.self, iVal)
// if we got an unexpected error, bail.
if err != nil && err != ds.ErrNotFound {
return nil, err
}
// if we have the value, send it back
if err == nil {
log.Debugf("%s handleGetValue success!", dht.self)
byts, ok := iVal.([]byte)
if !ok {
return nil, fmt.Errorf("datastore had non byte-slice value for %v", dskey)
}
rec := new(pb.Record)
err := proto.Unmarshal(byts, rec)
if err != nil {
log.Debug("Failed to unmarshal dht record from datastore")
return nil, err
}
resp.Record = rec
}
// Find closest peer on given cluster to desired key and reply with that info
closer := dht.betterPeersToQuery(pmes, p, CloserPeerCount)
if len(closer) > 0 {
closerinfos := peer.PeerInfos(dht.peerstore, closer)
for _, pi := range closerinfos {
log.Debugf("handleGetValue returning closer peer: '%s'", pi.ID)
if len(pi.Addrs) < 1 {
log.Errorf(`no addresses on peer being sent!
[local:%s]
[sending:%s]
[remote:%s]`, dht.self, pi.ID, p)
}
}
resp.CloserPeers = pb.PeerInfosToPBPeers(dht.host.Network(), closerinfos)
}
return resp, nil
}
func (s *Server) handleMessage(
ctx context.Context, p peer.ID, req *dhtpb.Message) (peer.ID, *dhtpb.Message) {
defer log.EventBegin(ctx, "routingMessageReceived", req, p).Done()
var response = dhtpb.NewMessage(req.GetType(), req.GetKey(), req.GetClusterLevel())
switch req.GetType() {
case dhtpb.Message_GET_VALUE:
rawRecord, err := getRoutingRecord(s.routingBackend, key.Key(req.GetKey()))
if err != nil {
return "", nil
}
response.Record = rawRecord
return p, response
case dhtpb.Message_PUT_VALUE:
// FIXME: verify complains that the peer's ID is not present in the
// peerstore. Mocknet problem?
// if err := verify(s.peerstore, req.GetRecord()); err != nil {
// log.Event(ctx, "validationFailed", req, p)
// return "", nil
// }
putRoutingRecord(s.routingBackend, key.Key(req.GetKey()), req.GetRecord())
return p, req
case dhtpb.Message_FIND_NODE:
p := s.peerstore.PeerInfo(peer.ID(req.GetKey()))
pri := []dhtpb.PeerRoutingInfo{
{
PeerInfo: p,
// Connectedness: TODO
},
}
response.CloserPeers = dhtpb.PeerRoutingInfosToPBPeers(pri)
return p.ID, response
case dhtpb.Message_ADD_PROVIDER:
for _, provider := range req.GetProviderPeers() {
providerID := peer.ID(provider.GetId())
if providerID == p {
store := []*dhtpb.Message_Peer{provider}
storeProvidersToPeerstore(s.peerstore, p, store)
if err := putRoutingProviders(s.routingBackend, key.Key(req.GetKey()), store); err != nil {
return "", nil
}
} else {
log.Event(ctx, "addProviderBadRequest", p, req)
}
}
return "", nil
case dhtpb.Message_GET_PROVIDERS:
providers, err := getRoutingProviders(s.routingBackend, key.Key(req.GetKey()))
if err != nil {
return "", nil
}
response.ProviderPeers = providers
return p, response
case dhtpb.Message_PING:
return p, req
default:
}
return "", nil
}