func (d *Diagnostics) getDiagnosticFromPeer(ctx context.Context, p peer.ID, pmes *pb.Message) (<-chan *DiagInfo, error) {
s, err := d.host.NewStream(ProtocolDiag, p)
if err != nil {
return nil, err
}
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
}
out := make(chan *DiagInfo)
go func() {
defer func() {
close(out)
s.Close()
rtt := time.Since(start)
log.Infof("diagnostic request took: %s", rtt.String())
}()
for {
rpmes := new(pb.Message)
if err := r.ReadMsg(rpmes); err != nil {
log.Debugf("Error reading diagnostic from stream: %s", err)
return
}
if rpmes == nil {
log.Debug("Got no response back from diag request.")
return
}
di, err := decodeDiagJson(rpmes.GetData())
if err != nil {
log.Debug(err)
return
}
select {
case out <- di:
case <-ctx.Done():
return
}
}
}()
return out, nil
}
func (d *Diagnostics) HandleMessage(ctx context.Context, s inet.Stream) error {
cr := ctxio.NewReader(ctx, s)
cw := ctxio.NewWriter(ctx, s)
r := ggio.NewDelimitedReader(cr, inet.MessageSizeMax) // maxsize
w := ggio.NewDelimitedWriter(cw)
// deserialize msg
pmes := new(pb.Message)
if err := r.ReadMsg(pmes); err != nil {
log.Debugf("Failed to decode protobuf message: %v", err)
return nil
}
// Print out diagnostic
log.Infof("[peer: %s] Got message from [%s]\n",
d.self.Pretty(), s.Conn().RemotePeer())
// Make sure we havent already handled this request to prevent loops
if err := d.startDiag(pmes.GetDiagID()); err != nil {
return nil
}
resp := newMessage(pmes.GetDiagID())
resp.Data = d.getDiagInfo().Marshal()
if err := w.WriteMsg(resp); err != nil {
log.Debugf("Failed to write protobuf message over stream: %s", err)
return err
}
timeout := pmes.GetTimeoutDuration()
if timeout < HopTimeoutDecrement {
return fmt.Errorf("timeout too short: %s", timeout)
}
ctx, cancel := context.WithTimeout(ctx, timeout)
defer cancel()
pmes.SetTimeoutDuration(timeout - HopTimeoutDecrement)
dpeers, err := d.getDiagnosticFromPeers(ctx, d.getPeers(), pmes)
if err != nil {
log.Debugf("diagnostic from peers err: %s", err)
return err
}
for b := range dpeers {
resp := newMessage(pmes.GetDiagID())
resp.Data = b.Marshal()
if err := w.WriteMsg(resp); err != nil {
log.Debugf("Failed to write protobuf message over stream: %s", err)
return err
}
}
return nil
}
func newMessage(diagID string) *pb.Message {
pmes := new(pb.Message)
pmes.DiagID = proto.String(diagID)
return pmes
}