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
}
// sendRequest sends out a request, but also makes sure to
// measure the RTT for latency measurements.
func (dht *IpfsDHT) sendRequest(ctx context.Context, p peer.ID, pmes *pb.Message) (*pb.Message, error) {
log.Debugf("%s dht starting stream", dht.self)
s, err := dht.host.NewStream(ProtocolDHT, p)
if err != nil {
return nil, err
}
defer s.Close()
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)
start := time.Now()
if err := w.WriteMsg(pmes); err != nil {
return nil, err
}
log.Event(ctx, "dhtSentMessage", dht.self, p, pmes)
rpmes := new(pb.Message)
if err := r.ReadMsg(rpmes); err != nil {
return nil, err
}
if rpmes == nil {
return nil, errors.New("no response to request")
}
// update the peer (on valid msgs only)
dht.updateFromMessage(ctx, p, rpmes)
dht.peerstore.RecordLatency(p, time.Since(start))
log.Event(ctx, "dhtReceivedMessage", dht.self, p, rpmes)
return rpmes, nil
}