func (ss *serverStream) SetTrailer(md metadata.MD) {
if md.Len() == 0 {
return
}
ss.s.SetTrailer(md)
return
}
// SetTrailer sets the trailer metadata which will be sent with the RPC status
// by the server. This can only be called at most once. Server side only.
func (s *Stream) SetTrailer(md metadata.MD) error {
s.mu.Lock()
defer s.mu.Unlock()
if s.trailer != nil {
return ErrIllegalTrailerSet
}
s.trailer = md.Copy()
return nil
}
// SetTrailer sets the trailer metadata which will be sent with the RPC status
// by the server. This can be called multiple times. Server side only.
func (s *Stream) SetTrailer(md metadata.MD) error {
if md.Len() == 0 {
return nil
}
s.mu.Lock()
defer s.mu.Unlock()
s.trailer = metadata.Join(s.trailer, md)
return nil
}
// SetTrailer sets the trailer metadata that will be sent when an RPC returns.
// It may be called at most once from a unary RPC handler. The ctx is the RPC
// handler's Context or one derived from it.
func SetTrailer(ctx context.Context, md metadata.MD) error {
if md.Len() == 0 {
return nil
}
stream, ok := transport.StreamFromContext(ctx)
if !ok {
return fmt.Errorf("grpc: failed to fetch the stream from the context %v", ctx)
}
return stream.SetTrailer(md)
}
// SetHeader sets the header metadata. This can be called multiple times.
// Server side only.
func (s *Stream) SetHeader(md metadata.MD) error {
s.mu.Lock()
defer s.mu.Unlock()
if s.headerOk || s.state == streamDone {
return ErrIllegalHeaderWrite
}
if md.Len() == 0 {
return nil
}
s.header = metadata.Join(s.header, md)
return nil
}
// SendHeader sends header metadata. It may be called at most once from a unary
// RPC handler. The ctx is the RPC handler's Context or one derived from it.
func SendHeader(ctx context.Context, md metadata.MD) error {
if md.Len() == 0 {
return nil
}
stream, ok := transport.StreamFromContext(ctx)
if !ok {
return fmt.Errorf("grpc: failed to fetch the stream from the context %v", ctx)
}
t := stream.ServerTransport()
if t == nil {
grpclog.Fatalf("grpc: SendHeader: %v has no ServerTransport to send header metadata.", stream)
}
return t.WriteHeader(stream, md)
}
// WriteHeader sends the header metedata md back to the client.
func (t *http2Server) WriteHeader(s *Stream, md metadata.MD) error {
s.mu.Lock()
if s.headerOk || s.state == streamDone {
s.mu.Unlock()
return ErrIllegalHeaderWrite
}
s.headerOk = true
if md.Len() > 0 {
if s.header.Len() > 0 {
s.header = metadata.Join(s.header, md)
} else {
s.header = md
}
}
md = s.header
s.mu.Unlock()
if _, err := wait(s.ctx, nil, nil, t.shutdownChan, t.writableChan); err != nil {
return err
}
t.hBuf.Reset()
t.hEnc.WriteField(hpack.HeaderField{Name: ":status", Value: "200"})
t.hEnc.WriteField(hpack.HeaderField{Name: "content-type", Value: "application/grpc"})
if s.sendCompress != "" {
t.hEnc.WriteField(hpack.HeaderField{Name: "grpc-encoding", Value: s.sendCompress})
}
for k, v := range md {
if isReservedHeader(k) {
// Clients don't tolerate reading restricted headers after some non restricted ones were sent.
continue
}
for _, entry := range v {
t.hEnc.WriteField(hpack.HeaderField{Name: k, Value: entry})
}
}
bufLen := t.hBuf.Len()
if err := t.writeHeaders(s, t.hBuf, false); err != nil {
return err
}
if stats.On() {
outHeader := &stats.OutHeader{
WireLength: bufLen,
}
stats.HandleRPC(s.Context(), outHeader)
}
t.writableChan <- 0
return nil
}
func (ss *serverStream) SetHeader(md metadata.MD) error {
if md.Len() == 0 {
return nil
}
return ss.s.SetHeader(md)
}