snapshot of https://github.com/grpc/grpc-go.git (master, 2026-09-15; blobs > 131072B omitted)

channelz/internal/protoconv/channel.go

@@ -0,0 +1,136 @@
+/*
+ *
+ * Copyright 2024 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package protoconv
+
+import (
+	"time"
+
+	"google.golang.org/grpc/codes"
+	"google.golang.org/grpc/connectivity"
+	"google.golang.org/grpc/internal/channelz"
+	"google.golang.org/grpc/status"
+	"google.golang.org/protobuf/types/known/timestamppb"
+
+	channelzpb "google.golang.org/grpc/channelz/grpc_channelz_v1"
+)
+
+func connectivityStateToProto(s *connectivity.State) *channelzpb.ChannelConnectivityState {
+	if s == nil {
+		return &channelzpb.ChannelConnectivityState{State: channelzpb.ChannelConnectivityState_UNKNOWN}
+	}
+	switch *s {
+	case connectivity.Idle:
+		return &channelzpb.ChannelConnectivityState{State: channelzpb.ChannelConnectivityState_IDLE}
+	case connectivity.Connecting:
+		return &channelzpb.ChannelConnectivityState{State: channelzpb.ChannelConnectivityState_CONNECTING}
+	case connectivity.Ready:
+		return &channelzpb.ChannelConnectivityState{State: channelzpb.ChannelConnectivityState_READY}
+	case connectivity.TransientFailure:
+		return &channelzpb.ChannelConnectivityState{State: channelzpb.ChannelConnectivityState_TRANSIENT_FAILURE}
+	case connectivity.Shutdown:
+		return &channelzpb.ChannelConnectivityState{State: channelzpb.ChannelConnectivityState_SHUTDOWN}
+	default:
+		return &channelzpb.ChannelConnectivityState{State: channelzpb.ChannelConnectivityState_UNKNOWN}
+	}
+}
+
+func channelTraceToProto(ct *channelz.ChannelTrace) *channelzpb.ChannelTrace {
+	pbt := &channelzpb.ChannelTrace{}
+	if ct == nil {
+		return pbt
+	}
+	pbt.NumEventsLogged = ct.EventNum
+	if ts := timestamppb.New(ct.CreationTime); ts.IsValid() {
+		pbt.CreationTimestamp = ts
+	}
+	events := make([]*channelzpb.ChannelTraceEvent, 0, len(ct.Events))
+	for _, e := range ct.Events {
+		cte := &channelzpb.ChannelTraceEvent{
+			Description: e.Desc,
+			Severity:    channelzpb.ChannelTraceEvent_Severity(e.Severity),
+		}
+		if ts := timestamppb.New(e.Timestamp); ts.IsValid() {
+			cte.Timestamp = ts
+		}
+		if e.RefID != 0 {
+			switch e.RefType {
+			case channelz.RefChannel:
+				cte.ChildRef = &channelzpb.ChannelTraceEvent_ChannelRef{ChannelRef: &channelzpb.ChannelRef{ChannelId: e.RefID, Name: e.RefName}}
+			case channelz.RefSubChannel:
+				cte.ChildRef = &channelzpb.ChannelTraceEvent_SubchannelRef{SubchannelRef: &channelzpb.SubchannelRef{SubchannelId: e.RefID, Name: e.RefName}}
+			}
+		}
+		events = append(events, cte)
+	}
+	pbt.Events = events
+	return pbt
+}
+
+func channelToProto(cm *channelz.Channel) *channelzpb.Channel {
+	c := &channelzpb.Channel{}
+	c.Ref = &channelzpb.ChannelRef{ChannelId: cm.ID, Name: cm.RefName}
+
+	c.Data = &channelzpb.ChannelData{
+		State:          connectivityStateToProto(cm.ChannelMetrics.State.Load()),
+		Target:         strFromPointer(cm.ChannelMetrics.Target.Load()),
+		CallsStarted:   cm.ChannelMetrics.CallsStarted.Load(),
+		CallsSucceeded: cm.ChannelMetrics.CallsSucceeded.Load(),
+		CallsFailed:    cm.ChannelMetrics.CallsFailed.Load(),
+	}
+	if ts := timestamppb.New(time.Unix(0, cm.ChannelMetrics.LastCallStartedTimestamp.Load())); ts.IsValid() {
+		c.Data.LastCallStartedTimestamp = ts
+	}
+	ncs := cm.NestedChans()
+	nestedChans := make([]*channelzpb.ChannelRef, 0, len(ncs))
+	for id, ref := range ncs {
+		nestedChans = append(nestedChans, &channelzpb.ChannelRef{ChannelId: id, Name: ref})
+	}
+	c.ChannelRef = nestedChans
+
+	scs := cm.SubChans()
+	subChans := make([]*channelzpb.SubchannelRef, 0, len(scs))
+	for id, ref := range scs {
+		subChans = append(subChans, &channelzpb.SubchannelRef{SubchannelId: id, Name: ref})
+	}
+	c.SubchannelRef = subChans
+
+	c.Data.Trace = channelTraceToProto(cm.Trace())
+	return c
+}
+
+// GetTopChannels returns the protobuf representation of the channels starting
+// at startID (max of len), and returns end=true if no top channels exist with
+// higher IDs.
+func GetTopChannels(startID int64, len int) (channels []*channelzpb.Channel, end bool) {
+	chans, end := channelz.GetTopChannels(startID, len)
+	for _, ch := range chans {
+		channels = append(channels, channelToProto(ch))
+	}
+	return channels, end
+}
+
+// GetChannel returns the protobuf representation of the channel with the given
+// ID.
+func GetChannel(id int64) (*channelzpb.Channel, error) {
+	ch := channelz.GetChannel(id)
+	if ch == nil {
+		return nil, status.Errorf(codes.NotFound, "requested channel %d not found", id)
+	}
+	return channelToProto(ch), nil
+}

channelz/internal/protoconv/server.go

@@ -0,0 +1,73 @@
+/*
+ *
+ * Copyright 2024 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package protoconv
+
+import (
+	"time"
+
+	"google.golang.org/grpc/codes"
+	"google.golang.org/grpc/internal/channelz"
+	"google.golang.org/grpc/status"
+	"google.golang.org/protobuf/types/known/timestamppb"
+
+	channelzpb "google.golang.org/grpc/channelz/grpc_channelz_v1"
+)
+
+func serverToProto(sm *channelz.Server) *channelzpb.Server {
+	s := &channelzpb.Server{}
+	s.Ref = &channelzpb.ServerRef{ServerId: sm.ID, Name: sm.RefName}
+
+	s.Data = &channelzpb.ServerData{
+		CallsStarted:   sm.ServerMetrics.CallsStarted.Load(),
+		CallsSucceeded: sm.ServerMetrics.CallsSucceeded.Load(),
+		CallsFailed:    sm.ServerMetrics.CallsFailed.Load(),
+	}
+
+	if ts := timestamppb.New(time.Unix(0, sm.ServerMetrics.LastCallStartedTimestamp.Load())); ts.IsValid() {
+		s.Data.LastCallStartedTimestamp = ts
+	}
+	lss := sm.ListenSockets()
+	sockets := make([]*channelzpb.SocketRef, 0, len(lss))
+	for id, ref := range lss {
+		sockets = append(sockets, &channelzpb.SocketRef{SocketId: id, Name: ref})
+	}
+	s.ListenSocket = sockets
+	return s
+}
+
+// GetServers returns the protobuf representation of the servers starting at
+// startID (max of len), and returns end=true if no servers exist with higher
+// IDs.
+func GetServers(startID int64, len int) (servers []*channelzpb.Server, end bool) {
+	srvs, end := channelz.GetServers(startID, len)
+	for _, srv := range srvs {
+		servers = append(servers, serverToProto(srv))
+	}
+	return servers, end
+}
+
+// GetServer returns the protobuf representation of the server with the given
+// ID.
+func GetServer(id int64) (*channelzpb.Server, error) {
+	srv := channelz.GetServer(id)
+	if srv == nil {
+		return nil, status.Errorf(codes.NotFound, "requested server %d not found", id)
+	}
+	return serverToProto(srv), nil
+}

channelz/internal/protoconv/socket.go

@@ -0,0 +1,136 @@
+/*
+ *
+ * Copyright 2024 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package protoconv
+
+import (
+	"net"
+	"time"
+
+	"google.golang.org/grpc/codes"
+	"google.golang.org/grpc/credentials"
+	"google.golang.org/grpc/internal/channelz"
+	"google.golang.org/grpc/status"
+	"google.golang.org/protobuf/types/known/anypb"
+	"google.golang.org/protobuf/types/known/timestamppb"
+	"google.golang.org/protobuf/types/known/wrapperspb"
+
+	channelzpb "google.golang.org/grpc/channelz/grpc_channelz_v1"
+)
+
+func securityToProto(se credentials.ChannelzSecurityValue) *channelzpb.Security {
+	switch v := se.(type) {
+	case *credentials.TLSChannelzSecurityValue:
+		return &channelzpb.Security{Model: &channelzpb.Security_Tls_{Tls: &channelzpb.Security_Tls{
+			CipherSuite:       &channelzpb.Security_Tls_StandardName{StandardName: v.StandardName},
+			LocalCertificate:  v.LocalCertificate,
+			RemoteCertificate: v.RemoteCertificate,
+		}}}
+	case *credentials.OtherChannelzSecurityValue:
+		otherSecurity := &channelzpb.Security_OtherSecurity{
+			Name: v.Name,
+		}
+		if anyval, err := anypb.New(v.Value); err == nil {
+			otherSecurity.Value = anyval
+		}
+		return &channelzpb.Security{Model: &channelzpb.Security_Other{Other: otherSecurity}}
+	}
+	return nil
+}
+
+func addrToProto(a net.Addr) *channelzpb.Address {
+	if a == nil {
+		return nil
+	}
+	switch a.Network() {
+	case "udp":
+		// TODO: Address_OtherAddress{}. Need proto def for Value.
+	case "ip":
+		// Note zone info is discarded through the conversion.
+		return &channelzpb.Address{Address: &channelzpb.Address_TcpipAddress{TcpipAddress: &channelzpb.Address_TcpIpAddress{IpAddress: a.(*net.IPAddr).IP}}}
+	case "ip+net":
+		// Note mask info is discarded through the conversion.
+		return &channelzpb.Address{Address: &channelzpb.Address_TcpipAddress{TcpipAddress: &channelzpb.Address_TcpIpAddress{IpAddress: a.(*net.IPNet).IP}}}
+	case "tcp":
+		// Note zone info is discarded through the conversion.
+		return &channelzpb.Address{Address: &channelzpb.Address_TcpipAddress{TcpipAddress: &channelzpb.Address_TcpIpAddress{IpAddress: a.(*net.TCPAddr).IP, Port: int32(a.(*net.TCPAddr).Port)}}}
+	case "unix", "unixgram", "unixpacket":
+		return &channelzpb.Address{Address: &channelzpb.Address_UdsAddress_{UdsAddress: &channelzpb.Address_UdsAddress{Filename: a.String()}}}
+	default:
+	}
+	return &channelzpb.Address{}
+}
+
+func socketToProto(skt *channelz.Socket) *channelzpb.Socket {
+	s := &channelzpb.Socket{}
+	s.Ref = &channelzpb.SocketRef{SocketId: skt.ID, Name: skt.RefName}
+
+	s.Data = &channelzpb.SocketData{
+		StreamsStarted:   skt.SocketMetrics.StreamsStarted.Load(),
+		StreamsSucceeded: skt.SocketMetrics.StreamsSucceeded.Load(),
+		StreamsFailed:    skt.SocketMetrics.StreamsFailed.Load(),
+		MessagesSent:     skt.SocketMetrics.MessagesSent.Load(),
+		MessagesReceived: skt.SocketMetrics.MessagesReceived.Load(),
+		KeepAlivesSent:   skt.SocketMetrics.KeepAlivesSent.Load(),
+	}
+	if ts := timestamppb.New(time.Unix(0, skt.SocketMetrics.LastLocalStreamCreatedTimestamp.Load())); ts.IsValid() {
+		s.Data.LastLocalStreamCreatedTimestamp = ts
+	}
+	if ts := timestamppb.New(time.Unix(0, skt.SocketMetrics.LastRemoteStreamCreatedTimestamp.Load())); ts.IsValid() {
+		s.Data.LastRemoteStreamCreatedTimestamp = ts
+	}
+	if ts := timestamppb.New(time.Unix(0, skt.SocketMetrics.LastMessageSentTimestamp.Load())); ts.IsValid() {
+		s.Data.LastMessageSentTimestamp = ts
+	}
+	if ts := timestamppb.New(time.Unix(0, skt.SocketMetrics.LastMessageReceivedTimestamp.Load())); ts.IsValid() {
+		s.Data.LastMessageReceivedTimestamp = ts
+	}
+	if skt.EphemeralMetrics != nil {
+		e := skt.EphemeralMetrics()
+		s.Data.LocalFlowControlWindow = wrapperspb.Int64(e.LocalFlowControlWindow)
+		s.Data.RemoteFlowControlWindow = wrapperspb.Int64(e.RemoteFlowControlWindow)
+	}
+
+	s.Data.Option = sockoptToProto(skt.SocketOptions)
+	s.Security = securityToProto(skt.Security)
+	s.Local = addrToProto(skt.LocalAddr)
+	s.Remote = addrToProto(skt.RemoteAddr)
+	s.RemoteName = skt.RemoteName
+	return s
+}
+
+// GetServerSockets returns the protobuf representation of the server (listen)
+// sockets starting at startID (max of len), and returns end=true if no server
+// sockets exist with higher IDs.
+func GetServerSockets(serverID, startID int64, len int) (sockets []*channelzpb.SocketRef, end bool) {
+	skts, end := channelz.GetServerSockets(serverID, startID, len)
+	for _, m := range skts {
+		sockets = append(sockets, &channelzpb.SocketRef{SocketId: m.ID, Name: m.RefName})
+	}
+	return sockets, end
+}
+
+// GetSocket returns the protobuf representation of the socket with the given
+// ID.
+func GetSocket(id int64) (*channelzpb.Socket, error) {
+	skt := channelz.GetSocket(id)
+	if skt == nil {
+		return nil, status.Errorf(codes.NotFound, "requested socket %d not found", id)
+	}
+	return socketToProto(skt), nil
+}

channelz/internal/protoconv/sockopt_linux.go

@@ -0,0 +1,125 @@
+/*
+ *
+ * Copyright 2018 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package protoconv
+
+import (
+	"time"
+
+	"google.golang.org/grpc/grpclog"
+	"google.golang.org/grpc/internal/channelz"
+
+	channelzpb "google.golang.org/grpc/channelz/grpc_channelz_v1"
+	"google.golang.org/protobuf/types/known/anypb"
+	"google.golang.org/protobuf/types/known/durationpb"
+)
+
+var logger = grpclog.Component("channelz")
+
+func convertToPbDuration(sec int64, usec int64) *durationpb.Duration {
+	return durationpb.New(time.Duration(sec*1e9 + usec*1e3))
+}
+
+func sockoptToProto(skopts *channelz.SocketOptionData) []*channelzpb.SocketOption {
+	if skopts == nil {
+		return nil
+	}
+	var opts []*channelzpb.SocketOption
+	if skopts.Linger != nil {
+		additional, err := anypb.New(&channelzpb.SocketOptionLinger{
+			Active:   skopts.Linger.Onoff != 0,
+			Duration: convertToPbDuration(int64(skopts.Linger.Linger), 0),
+		})
+		if err == nil {
+			opts = append(opts, &channelzpb.SocketOption{
+				Name:       "SO_LINGER",
+				Additional: additional,
+			})
+		} else {
+			logger.Warningf("Failed to marshal socket options linger %+v: %v", skopts.Linger, err)
+		}
+	}
+	if skopts.RecvTimeout != nil {
+		additional, err := anypb.New(&channelzpb.SocketOptionTimeout{
+			Duration: convertToPbDuration(int64(skopts.RecvTimeout.Sec), int64(skopts.RecvTimeout.Usec)),
+		})
+		if err == nil {
+			opts = append(opts, &channelzpb.SocketOption{
+				Name:       "SO_RCVTIMEO",
+				Additional: additional,
+			})
+		} else {
+			logger.Warningf("Failed to marshal socket options receive timeout %+v: %v", skopts.RecvTimeout, err)
+		}
+	}
+	if skopts.SendTimeout != nil {
+		additional, err := anypb.New(&channelzpb.SocketOptionTimeout{
+			Duration: convertToPbDuration(int64(skopts.SendTimeout.Sec), int64(skopts.SendTimeout.Usec)),
+		})
+		if err == nil {
+			opts = append(opts, &channelzpb.SocketOption{
+				Name:       "SO_SNDTIMEO",
+				Additional: additional,
+			})
+		} else {
+			logger.Warningf("Failed to marshal socket options send timeout %+v: %v", skopts.SendTimeout, err)
+		}
+	}
+	if skopts.TCPInfo != nil {
+		additional, err := anypb.New(&channelzpb.SocketOptionTcpInfo{
+			TcpiState:       uint32(skopts.TCPInfo.State),
+			TcpiCaState:     uint32(skopts.TCPInfo.Ca_state),
+			TcpiRetransmits: uint32(skopts.TCPInfo.Retransmits),
+			TcpiProbes:      uint32(skopts.TCPInfo.Probes),
+			TcpiBackoff:     uint32(skopts.TCPInfo.Backoff),
+			TcpiOptions:     uint32(skopts.TCPInfo.Options),
+			// https://golang.org/pkg/syscall/#TCPInfo
+			// TCPInfo struct does not contain info about TcpiSndWscale and TcpiRcvWscale.
+			TcpiRto:          skopts.TCPInfo.Rto,
+			TcpiAto:          skopts.TCPInfo.Ato,
+			TcpiSndMss:       skopts.TCPInfo.Snd_mss,
+			TcpiRcvMss:       skopts.TCPInfo.Rcv_mss,
+			TcpiUnacked:      skopts.TCPInfo.Unacked,
+			TcpiSacked:       skopts.TCPInfo.Sacked,
+			TcpiLost:         skopts.TCPInfo.Lost,
+			TcpiRetrans:      skopts.TCPInfo.Retrans,
+			TcpiFackets:      skopts.TCPInfo.Fackets,
+			TcpiLastDataSent: skopts.TCPInfo.Last_data_sent,
+			TcpiLastAckSent:  skopts.TCPInfo.Last_ack_sent,
+			TcpiLastDataRecv: skopts.TCPInfo.Last_data_recv,
+			TcpiLastAckRecv:  skopts.TCPInfo.Last_ack_recv,
+			TcpiPmtu:         skopts.TCPInfo.Pmtu,
+			TcpiRcvSsthresh:  skopts.TCPInfo.Rcv_ssthresh,
+			TcpiRtt:          skopts.TCPInfo.Rtt,
+			TcpiRttvar:       skopts.TCPInfo.Rttvar,
+			TcpiSndSsthresh:  skopts.TCPInfo.Snd_ssthresh,
+			TcpiSndCwnd:      skopts.TCPInfo.Snd_cwnd,
+			TcpiAdvmss:       skopts.TCPInfo.Advmss,
+			TcpiReordering:   skopts.TCPInfo.Reordering,
+		})
+		if err == nil {
+			opts = append(opts, &channelzpb.SocketOption{
+				Name:       "TCP_INFO",
+				Additional: additional,
+			})
+		} else {
+			logger.Warningf("Failed to marshal socket options TCP info %+v: %v", skopts.TCPInfo, err)
+		}
+	}
+	return opts
+}

channelz/internal/protoconv/sockopt_nonlinux.go

@@ -0,0 +1,31 @@
+//go:build !linux
+// +build !linux
+
+/*
+ *
+ * Copyright 2018 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package protoconv
+
+import (
+	channelzpb "google.golang.org/grpc/channelz/grpc_channelz_v1"
+	"google.golang.org/grpc/internal/channelz"
+)
+
+func sockoptToProto(_ *channelz.SocketOptionData) []*channelzpb.SocketOption {
+	return nil
+}

channelz/internal/protoconv/subchannel.go

@@ -0,0 +1,65 @@
+/*
+ *
+ * Copyright 2024 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package protoconv
+
+import (
+	"time"
+
+	"google.golang.org/grpc/codes"
+	"google.golang.org/grpc/internal/channelz"
+	"google.golang.org/grpc/status"
+	"google.golang.org/protobuf/types/known/timestamppb"
+
+	channelzpb "google.golang.org/grpc/channelz/grpc_channelz_v1"
+)
+
+func subChannelToProto(cm *channelz.SubChannel) *channelzpb.Subchannel {
+	sc := &channelzpb.Subchannel{}
+	sc.Ref = &channelzpb.SubchannelRef{SubchannelId: cm.ID, Name: cm.RefName}
+
+	sc.Data = &channelzpb.ChannelData{
+		State:          connectivityStateToProto(cm.ChannelMetrics.State.Load()),
+		Target:         strFromPointer(cm.ChannelMetrics.Target.Load()),
+		CallsStarted:   cm.ChannelMetrics.CallsStarted.Load(),
+		CallsSucceeded: cm.ChannelMetrics.CallsSucceeded.Load(),
+		CallsFailed:    cm.ChannelMetrics.CallsFailed.Load(),
+	}
+	if ts := timestamppb.New(time.Unix(0, cm.ChannelMetrics.LastCallStartedTimestamp.Load())); ts.IsValid() {
+		sc.Data.LastCallStartedTimestamp = ts
+	}
+
+	skts := cm.Sockets()
+	sockets := make([]*channelzpb.SocketRef, 0, len(skts))
+	for id, ref := range skts {
+		sockets = append(sockets, &channelzpb.SocketRef{SocketId: id, Name: ref})
+	}
+	sc.SocketRef = sockets
+	sc.Data.Trace = channelTraceToProto(cm.Trace())
+	return sc
+}
+
+// GetSubChannel returns the protobuf representation of the subchannel with the
+// given ID.
+func GetSubChannel(id int64) (*channelzpb.Subchannel, error) {
+	subChan := channelz.GetSubChannel(id)
+	if subChan == nil {
+		return nil, status.Errorf(codes.NotFound, "requested sub channel %d not found", id)
+	}
+	return subChannelToProto(subChan), nil
+}

channelz/internal/protoconv/util.go

@@ -0,0 +1,28 @@
+/*
+ *
+ * Copyright 2024 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+// Package protoconv supports converting between the internal channelz
+// implementation and the protobuf representation of all the entities.
+package protoconv
+
+func strFromPointer(s *string) string {
+	if s == nil {
+		return ""
+	}
+	return *s
+}