func TestHostProtoPreference(t *testing.T) {
ctx, cancel := context.WithCancel(context.Background())
defer cancel()
h1, h2 := getHostPair(ctx, t)
defer h1.Close()
defer h2.Close()
protoOld := protocol.ID("/testing")
protoNew := protocol.ID("/testing/1.1.0")
protoMinor := protocol.ID("/testing/1.2.0")
connectedOn := make(chan protocol.ID, 16)
handler := func(s inet.Stream) {
connectedOn <- s.Protocol()
s.Close()
}
h1.SetStreamHandler(protoOld, handler)
s, err := h2.NewStream(ctx, h1.ID(), protoMinor, protoNew, protoOld)
if err != nil {
t.Fatal(err)
}
assertWait(t, connectedOn, protoOld)
s.Close()
mfunc, err := host.MultistreamSemverMatcher(protoMinor)
if err != nil {
t.Fatal(err)
}
h1.SetStreamHandlerMatch(protoMinor, mfunc, handler)
// remembered preference will be chosen first, even when the other side newly supports it
s2, err := h2.NewStream(ctx, h1.ID(), protoMinor, protoNew, protoOld)
if err != nil {
t.Fatal(err)
}
// required to force 'lazy' handshake
_, err = s2.Write([]byte("hello"))
if err != nil {
t.Fatal(err)
}
assertWait(t, connectedOn, protoOld)
s2.Close()
s3, err := h2.NewStream(ctx, h1.ID(), protoMinor)
if err != nil {
t.Fatal(err)
}
assertWait(t, connectedOn, protoMinor)
s3.Close()
}
// NewStream opens a new stream to given peer p, and writes a p2p/protocol
// header with given protocol.ID. If there is no connection to p, attempts
// to create one. If ProtocolID is "", writes no header.
// (Threadsafe)
func (h *BasicHost) NewStream(ctx context.Context, p peer.ID, pids ...protocol.ID) (inet.Stream, error) {
pref, err := h.preferredProtocol(p, pids)
if err != nil {
return nil, err
}
if pref != "" {
return h.newStream(ctx, p, pref)
}
var protoStrs []string
for _, pid := range pids {
protoStrs = append(protoStrs, string(pid))
}
s, err := h.Network().NewStream(ctx, p)
if err != nil {
return nil, err
}
selected, err := msmux.SelectOneOf(protoStrs, s)
if err != nil {
s.Close()
return nil, err
}
selpid := protocol.ID(selected)
s.SetProtocol(selpid)
h.Peerstore().AddProtocols(p, selected)
return mstream.WrapStream(s, h.bwc), nil
}
// newStreamHandler is the remote-opened stream handler for inet.Network
// TODO: this feels a bit wonky
func (h *BasicHost) newStreamHandler(s inet.Stream) {
before := time.Now()
protoID, handle, err := h.Mux().Negotiate(s)
took := time.Now().Sub(before)
if err != nil {
if err == io.EOF {
logf := log.Debugf
if took > time.Second*10 {
logf = log.Warningf
}
logf("protocol EOF: %s (took %s)", s.Conn().RemotePeer(), took)
} else {
log.Warning("protocol mux failed: %s (took %s)", err, took)
}
return
}
s.SetProtocol(protocol.ID(protoID))
if h.bwc != nil {
s = mstream.WrapStream(s, h.bwc)
}
log.Debugf("protocol negotiation took %s", took)
go handle(protoID, s)
}
// SetStreamHandlerMatch sets the protocol handler on the Host's Mux
// using a matching function to do protocol comparisons
func (h *BasicHost) SetStreamHandlerMatch(pid protocol.ID, m func(string) bool, handler inet.StreamHandler) {
h.Mux().AddHandlerWithFunc(string(pid), m, func(p string, rwc io.ReadWriteCloser) error {
is := rwc.(inet.Stream)
is.SetProtocol(protocol.ID(p))
handler(is)
return nil
})
}
func (h *BasicHost) preferredProtocol(p peer.ID, pids []protocol.ID) (protocol.ID, error) {
pidstrs := pidsToStrings(pids)
supported, err := h.Peerstore().SupportsProtocols(p, pidstrs...)
if err != nil {
return "", err
}
var out protocol.ID
if len(supported) > 0 {
out = protocol.ID(supported[0])
}
return out, nil
}
// newStreamHandler is the remote-opened stream handler for inet.Network
// TODO: this feels a bit wonky
func (h *BasicHost) newStreamHandler(s inet.Stream) {
before := time.Now()
if h.NegotiateTimeout != 0 {
if err := s.SetDeadline(time.Now().Add(h.NegotiateTimeout)); err != nil {
log.Error("setting stream deadline: ", err)
s.Close()
return
}
}
protoID, handle, err := h.Mux().Negotiate(s)
took := time.Now().Sub(before)
if err != nil {
if err == io.EOF {
logf := log.Debugf
if took > time.Second*10 {
logf = log.Warningf
}
logf("protocol EOF: %s (took %s)", s.Conn().RemotePeer(), took)
} else {
log.Warning("protocol mux failed: %s (took %s)", err, took)
}
s.Close()
return
}
if h.NegotiateTimeout != 0 {
if err := s.SetDeadline(time.Time{}); err != nil {
log.Error("resetting stream deadline: ", err)
s.Close()
return
}
}
s.SetProtocol(protocol.ID(protoID))
if h.bwc != nil {
s = mstream.WrapStream(s, h.bwc)
}
log.Debugf("protocol negotiation took %s", took)
go handle(protoID, s)
}