func (s *Server) sendResponse(t transport.ServerTransport, stream *transport.Stream, msg interface{}, cp Compressor, opts *transport.Options) error {
var (
cbuf *bytes.Buffer
outPayload *stats.OutPayload
)
if cp != nil {
cbuf = new(bytes.Buffer)
}
if stats.On() {
outPayload = &stats.OutPayload{}
}
p, err := encode(s.opts.codec, msg, cp, cbuf, outPayload)
if err != nil {
// This typically indicates a fatal issue (e.g., memory
// corruption or hardware faults) the application program
// cannot handle.
//
// TODO(zhaoq): There exist other options also such as only closing the
// faulty stream locally and remotely (Other streams can keep going). Find
// the optimal option.
grpclog.Fatalf("grpc: Server failed to encode response %v", err)
}
err = t.Write(stream, p, opts)
if err == nil && outPayload != nil {
outPayload.SentTime = time.Now()
stats.HandleRPC(stream.Context(), outPayload)
}
return err
}
func (cs *clientStream) SendMsg(m interface{}) (err error) {
if cs.tracing {
cs.mu.Lock()
if cs.trInfo.tr != nil {
cs.trInfo.tr.LazyLog(&payload{sent: true, msg: m}, true)
}
cs.mu.Unlock()
}
// TODO Investigate how to signal the stats handling party.
// generate error stats if err != nil && err != io.EOF?
defer func() {
if err != nil {
cs.finish(err)
}
if err == nil {
return
}
if err == io.EOF {
// Specialize the process for server streaming. SendMesg is only called
// once when creating the stream object. io.EOF needs to be skipped when
// the rpc is early finished (before the stream object is created.).
// TODO: It is probably better to move this into the generated code.
if !cs.desc.ClientStreams && cs.desc.ServerStreams {
err = nil
}
return
}
if _, ok := err.(transport.ConnectionError); !ok {
cs.closeTransportStream(err)
}
err = toRPCErr(err)
}()
var outPayload *stats.OutPayload
if stats.On() {
outPayload = &stats.OutPayload{
Client: true,
}
}
out, err := encode(cs.codec, m, cs.cp, cs.cbuf, outPayload)
defer func() {
if cs.cbuf != nil {
cs.cbuf.Reset()
}
}()
if err != nil {
return Errorf(codes.Internal, "grpc: %v", err)
}
err = cs.t.Write(cs.s, out, &transport.Options{Last: false})
if err == nil && outPayload != nil {
outPayload.SentTime = time.Now()
stats.HandleRPC(cs.statsCtx, outPayload)
}
return err
}
// encode serializes msg and prepends the message header. If msg is nil, it
// generates the message header of 0 message length.
func encode(c Codec, msg interface{}, cp Compressor, cbuf *bytes.Buffer, outPayload *stats.OutPayload) ([]byte, error) {
var (
b []byte
length uint
)
if msg != nil {
var err error
// TODO(zhaoq): optimize to reduce memory alloc and copying.
b, err = c.Marshal(msg)
if err != nil {
return nil, err
}
if outPayload != nil {
outPayload.Payload = msg
// TODO truncate large payload.
outPayload.Data = b
outPayload.Length = len(b)
}
if cp != nil {
if err := cp.Do(cbuf, b); err != nil {
return nil, err
}
b = cbuf.Bytes()
}
length = uint(len(b))
}
if length > math.MaxUint32 {
return nil, Errorf(codes.InvalidArgument, "grpc: message too large (%d bytes)", length)
}
const (
payloadLen = 1
sizeLen = 4
)
var buf = make([]byte, payloadLen+sizeLen+len(b))
// Write payload format
if cp == nil {
buf[0] = byte(compressionNone)
} else {
buf[0] = byte(compressionMade)
}
// Write length of b into buf
binary.BigEndian.PutUint32(buf[1:], uint32(length))
// Copy encoded msg to buf
copy(buf[5:], b)
if outPayload != nil {
outPayload.WireLength = len(buf)
}
return buf, nil
}
// sendRequest writes out various information of an RPC such as Context and Message.
func sendRequest(ctx context.Context, codec Codec, compressor Compressor, callHdr *transport.CallHdr, t transport.ClientTransport, args interface{}, opts *transport.Options) (_ *transport.Stream, err error) {
stream, err := t.NewStream(ctx, callHdr)
if err != nil {
return nil, err
}
defer func() {
if err != nil {
// If err is connection error, t will be closed, no need to close stream here.
if _, ok := err.(transport.ConnectionError); !ok {
t.CloseStream(stream, err)
}
}
}()
var (
cbuf *bytes.Buffer
outPayload *stats.OutPayload
)
if compressor != nil {
cbuf = new(bytes.Buffer)
}
if stats.On() {
outPayload = &stats.OutPayload{
Client: true,
}
}
outBuf, err := encode(codec, args, compressor, cbuf, outPayload)
if err != nil {
return nil, Errorf(codes.Internal, "grpc: %v", err)
}
err = t.Write(stream, outBuf, opts)
if err == nil && outPayload != nil {
outPayload.SentTime = time.Now()
stats.Handle(ctx, outPayload)
}
// t.NewStream(...) could lead to an early rejection of the RPC (e.g., the service/method
// does not exist.) so that t.Write could get io.EOF from wait(...). Leave the following
// recvResponse to get the final status.
if err != nil && err != io.EOF {
return nil, err
}
// Sent successfully.
return stream, nil
}
func (ss *serverStream) SendMsg(m interface{}) (err error) {
defer func() {
if ss.trInfo != nil {
ss.mu.Lock()
if ss.trInfo.tr != nil {
if err == nil {
ss.trInfo.tr.LazyLog(&payload{sent: true, msg: m}, true)
} else {
ss.trInfo.tr.LazyLog(&fmtStringer{"%v", []interface{}{err}}, true)
ss.trInfo.tr.SetError()
}
}
ss.mu.Unlock()
}
}()
var outPayload *stats.OutPayload
if stats.On() {
outPayload = &stats.OutPayload{}
}
out, err := encode(ss.codec, m, ss.cp, ss.cbuf, outPayload)
defer func() {
if ss.cbuf != nil {
ss.cbuf.Reset()
}
}()
if err != nil {
err = Errorf(codes.Internal, "grpc: %v", err)
return err
}
if err := ss.t.Write(ss.s, out, &transport.Options{Last: false}); err != nil {
return toRPCErr(err)
}
if outPayload != nil {
outPayload.SentTime = time.Now()
stats.HandleRPC(ss.s.Context(), outPayload)
}
return nil
}