add common Metadata message to be injected in reply messages by gRPC proxy

Makefile

@@ -13,4 +13,5 @@ reset-dev:
 
 .PHONY: proto
 proto:
-	protoc --go_out=. --go_opt=paths=source_relative --go-grpc_out=. --go-grpc_opt=paths=source_relative internal/machine/api/pb/*.proto
+	protoc --go_out=. --go_opt=paths=source_relative --go-grpc_out=. --go-grpc_opt=paths=source_relative \
+		--proto_path=. --proto_path=internal/machine/api/vendor internal/machine/api/pb/*.proto

go.mod

@@ -34,8 +34,8 @@ require (
 	golang.org/x/sys v0.26.0
 	golang.zx2c4.com/wireguard v0.0.0-20231211153847-12269c276173
 	golang.zx2c4.com/wireguard/wgctrl v0.0.0-20230429144221-925a1e7659e6
-	google.golang.org/grpc v1.66.0
+	google.golang.org/grpc v1.67.1
-	google.golang.org/protobuf v1.34.2
+	google.golang.org/protobuf v1.35.1
 )
 
 require (
@@ -151,6 +151,7 @@ require (
 	github.com/sean-/seed v0.0.0-20170313163322-e2103e2c3529 // indirect
 	github.com/shopspring/decimal v1.4.0 // indirect
 	github.com/siderolabs/gen v0.4.8 // indirect
+	github.com/siderolabs/grpc-proxy v0.5.1 // indirect
 	github.com/sirupsen/logrus v1.9.3 // indirect
 	github.com/spaolacci/murmur3 v1.1.0 // indirect
 	github.com/spf13/cast v1.7.0 // indirect
@@ -169,7 +170,7 @@ require (
 	golang.org/x/tools v0.26.0 // indirect
 	golang.zx2c4.com/wintun v0.0.0-20230126152724-0fa3db229ce2 // indirect
 	google.golang.org/genproto/googleapis/api v0.0.0-20240827150818-7e3bb234dfed // indirect
-	google.golang.org/genproto/googleapis/rpc v0.0.0-20240827150818-7e3bb234dfed // indirect
+	google.golang.org/genproto/googleapis/rpc v0.0.0-20241007155032-5fefd90f89a9 // indirect
 	gotest.tools/v3 v3.5.1 // indirect
 	gvisor.dev/gvisor v0.0.0-20230927004350-cbd86285d259 // indirect
 	lukechampine.com/blake3 v1.3.0 // indirect

go.sum

@@ -581,6 +581,8 @@ github.com/siderolabs/discovery-client v0.1.9 h1:yDzvts++Nf/2qczdDUfU5GAibkEIgz/
 github.com/siderolabs/discovery-client v0.1.9/go.mod h1:Ew1z07eyJwqNwum84IKYH4S649KEKK5WUmRW49HlXS8=
 github.com/siderolabs/gen v0.4.8 h1:VNpbmDLhkXp7qcSEkKk1Ee7vU2afs3xvHrWLGR2UuiY=
 github.com/siderolabs/gen v0.4.8/go.mod h1:7ROKVHHB68R3Amrd4a1ZXz/oMrXWF3Mg3lSEgnkJY5c=
+github.com/siderolabs/grpc-proxy v0.5.1 h1:WTZYLMPTZPt43BzEJ02LT9kYA9qAfquWwCezc6NPPYE=
+github.com/siderolabs/grpc-proxy v0.5.1/go.mod h1:EQwE87LiWxhiIUPBeWmpjJb9DIWxWID8R6ARtdTC+8A=
 github.com/sirupsen/logrus v1.2.0/go.mod h1:LxeOpSwHxABJmUn/MG1IvRgCAasNZTLOkJPxbbu5VWo=
 github.com/sirupsen/logrus v1.4.2/go.mod h1:tLMulIdttU9McNUspp0xgXVQah82FyeX6MwdIuYE2rE=
 github.com/sirupsen/logrus v1.9.3 h1:dueUQJ1C2q9oE3F7wvmSGAaVtTmUizReu6fjN8uqzbQ=
@@ -815,6 +817,8 @@ google.golang.org/genproto/googleapis/api v0.0.0-20240827150818-7e3bb234dfed h1:
 google.golang.org/genproto/googleapis/api v0.0.0-20240827150818-7e3bb234dfed/go.mod h1:OCdP9MfskevB/rbYvHTsXTtKC+3bHWajPdoKgjcYkfo=
 google.golang.org/genproto/googleapis/rpc v0.0.0-20240827150818-7e3bb234dfed h1:J6izYgfBXAI3xTKLgxzTmUltdYaLsuBxFCgDHWJ/eXg=
 google.golang.org/genproto/googleapis/rpc v0.0.0-20240827150818-7e3bb234dfed/go.mod h1:UqMtugtsSgubUsoxbuAoiCXvqvErP7Gf0so0mK9tHxU=
+google.golang.org/genproto/googleapis/rpc v0.0.0-20241007155032-5fefd90f89a9 h1:QCqS/PdaHTSWGvupk2F/ehwHtGc0/GYkT+3GAcR1CCc=
+google.golang.org/genproto/googleapis/rpc v0.0.0-20241007155032-5fefd90f89a9/go.mod h1:GX3210XPVPUjJbTUbvwI8f2IpZDMZuPJWDzDuebbviI=
 google.golang.org/grpc v1.19.0/go.mod h1:mqu4LbDTu4XGKhr4mRzUsmM4RtVoemTSY81AxZiDr8c=
 google.golang.org/grpc v1.20.1/go.mod h1:10oTOabMzJvdu6/UiuZezV6QK5dSlG84ov/aaiqXj38=
 google.golang.org/grpc v1.23.0/go.mod h1:Y5yQAOtifL1yxbo5wqy6BxZv8vAUGQwXBOALyacEbxg=
@@ -823,6 +827,8 @@ google.golang.org/grpc v1.27.0/go.mod h1:qbnxyOmOxrQa7FizSgH+ReBfzJrCY1pSN7KXBS8
 google.golang.org/grpc v1.33.2/go.mod h1:JMHMWHQWaTccqQQlmk3MJZS+GWXOdAesneDmEnv2fbc=
 google.golang.org/grpc v1.66.0 h1:DibZuoBznOxbDQxRINckZcUvnCEvrW9pcWIE2yF9r1c=
 google.golang.org/grpc v1.66.0/go.mod h1:s3/l6xSSCURdVfAnL+TqCNMyTDAGN6+lZeVxnZR128Y=
+google.golang.org/grpc v1.67.1 h1:zWnc1Vrcno+lHZCOofnIMvycFcc0QRGIzm9dhnDX68E=
+google.golang.org/grpc v1.67.1/go.mod h1:1gLDyUQU7CTLJI90u3nXZ9ekeghjeM7pTDZlqFNg2AA=
 google.golang.org/protobuf v0.0.0-20200109180630-ec00e32a8dfd/go.mod h1:DFci5gLYBciE7Vtevhsrf46CRTquxDuWsQurQQe4oz8=
 google.golang.org/protobuf v0.0.0-20200221191635-4d8936d0db64/go.mod h1:kwYJMbMJ01Woi6D6+Kah6886xMZcty6N08ah7+eCXa0=
 google.golang.org/protobuf v0.0.0-20200228230310-ab0ca4ff8a60/go.mod h1:cfTl7dwQJ+fmap5saPgwCLgHXTUD7jkjRqWcaiX5VyM=
@@ -834,6 +840,8 @@ google.golang.org/protobuf v1.23.1-0.20200526195155-81db48ad09cc/go.mod h1:EGpAD
 google.golang.org/protobuf v1.25.0/go.mod h1:9JNX74DMeImyA3h4bdi1ymwjUzf21/xIlbajtzgsN7c=
 google.golang.org/protobuf v1.34.2 h1:6xV6lTsCfpGD21XK49h7MhtcApnLqkfYgPcdHftf6hg=
 google.golang.org/protobuf v1.34.2/go.mod h1:qYOHts0dSfpeUzUFpOMr/WGzszTmLH+DiWniOlNbLDw=
+google.golang.org/protobuf v1.35.1 h1:m3LfL6/Ca+fqnjnlqQXNpFPABW1UD7mjh8KO2mKFytA=
+google.golang.org/protobuf v1.35.1/go.mod h1:9fA7Ob0pmnwhb644+1+CVWFRbNajQ6iRojtC/QF5bRE=
 gopkg.in/alecthomas/kingpin.v2 v2.2.6/go.mod h1:FMv+mEhP44yOT+4EoQTLFTRgOQ1FBLkstjWtayDeSgw=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/check.v1 v1.0.0-20180628173108-788fd7840127/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=

internal/machine/api/pb/common.pb.go

@@ -7,6 +7,7 @@
 package pb
 
 import (
+	status "google.golang.org/genproto/googleapis/rpc/status"
 	protoreflect "google.golang.org/protobuf/reflect/protoreflect"
 	protoimpl "google.golang.org/protobuf/runtime/protoimpl"
 	reflect "reflect"
@@ -20,6 +21,74 @@ const (
 	_ = protoimpl.EnforceVersion(protoimpl.MaxVersion - 20)
 )
 
+// Common metadata message nested in all reply message types, injected by the gRPC proxy to provide information
+// about the machine that responded to the request.
+type Metadata struct {
+	state         protoimpl.MessageState
+	sizeCache     protoimpl.SizeCache
+	unknownFields protoimpl.UnknownFields
+
+	// Address of the machine the response came from.
+	Machine string `protobuf:"bytes,1,opt,name=machine,proto3" json:"machine,omitempty"`
+	// error is set if the request to upstream failed. The rest of the response is undefined.
+	Error string `protobuf:"bytes,2,opt,name=error,proto3" json:"error,omitempty"`
+	// error as a gRPC Status message.
+	Status *status.Status `protobuf:"bytes,3,opt,name=status,proto3" json:"status,omitempty"`
+}
+
+func (x *Metadata) Reset() {
+	*x = Metadata{}
+	if protoimpl.UnsafeEnabled {
+		mi := &file_internal_machine_api_pb_common_proto_msgTypes[0]
+		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+		ms.StoreMessageInfo(mi)
+	}
+}
+
+func (x *Metadata) String() string {
+	return protoimpl.X.MessageStringOf(x)
+}
+
+func (*Metadata) ProtoMessage() {}
+
+func (x *Metadata) ProtoReflect() protoreflect.Message {
+	mi := &file_internal_machine_api_pb_common_proto_msgTypes[0]
+	if protoimpl.UnsafeEnabled && x != nil {
+		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+		if ms.LoadMessageInfo() == nil {
+			ms.StoreMessageInfo(mi)
+		}
+		return ms
+	}
+	return mi.MessageOf(x)
+}
+
+// Deprecated: Use Metadata.ProtoReflect.Descriptor instead.
+func (*Metadata) Descriptor() ([]byte, []int) {
+	return file_internal_machine_api_pb_common_proto_rawDescGZIP(), []int{0}
+}
+
+func (x *Metadata) GetMachine() string {
+	if x != nil {
+		return x.Machine
+	}
+	return ""
+}
+
+func (x *Metadata) GetError() string {
+	if x != nil {
+		return x.Error
+	}
+	return ""
+}
+
+func (x *Metadata) GetStatus() *status.Status {
+	if x != nil {
+		return x.Status
+	}
+	return nil
+}
+
 type IP struct {
 	state         protoimpl.MessageState
 	sizeCache     protoimpl.SizeCache
@@ -31,7 +100,7 @@ type IP struct {
 func (x *IP) Reset() {
 	*x = IP{}
 	if protoimpl.UnsafeEnabled {
-		mi := &file_internal_machine_api_pb_common_proto_msgTypes[0]
+		mi := &file_internal_machine_api_pb_common_proto_msgTypes[1]
 		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
 		ms.StoreMessageInfo(mi)
 	}
@@ -44,7 +113,7 @@ func (x *IP) String() string {
 func (*IP) ProtoMessage() {}
 
 func (x *IP) ProtoReflect() protoreflect.Message {
-	mi := &file_internal_machine_api_pb_common_proto_msgTypes[0]
+	mi := &file_internal_machine_api_pb_common_proto_msgTypes[1]
 	if protoimpl.UnsafeEnabled && x != nil {
 		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
 		if ms.LoadMessageInfo() == nil {
@@ -57,7 +126,7 @@ func (x *IP) ProtoReflect() protoreflect.Message {
 
 // Deprecated: Use IP.ProtoReflect.Descriptor instead.
 func (*IP) Descriptor() ([]byte, []int) {
-	return file_internal_machine_api_pb_common_proto_rawDescGZIP(), []int{0}
+	return file_internal_machine_api_pb_common_proto_rawDescGZIP(), []int{1}
 }
 
 func (x *IP) GetIp() []byte {
@@ -79,7 +148,7 @@ type IPPort struct {
 func (x *IPPort) Reset() {
 	*x = IPPort{}
 	if protoimpl.UnsafeEnabled {
-		mi := &file_internal_machine_api_pb_common_proto_msgTypes[1]
+		mi := &file_internal_machine_api_pb_common_proto_msgTypes[2]
 		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
 		ms.StoreMessageInfo(mi)
 	}
@@ -92,7 +161,7 @@ func (x *IPPort) String() string {
 func (*IPPort) ProtoMessage() {}
 
 func (x *IPPort) ProtoReflect() protoreflect.Message {
-	mi := &file_internal_machine_api_pb_common_proto_msgTypes[1]
+	mi := &file_internal_machine_api_pb_common_proto_msgTypes[2]
 	if protoimpl.UnsafeEnabled && x != nil {
 		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
 		if ms.LoadMessageInfo() == nil {
@@ -105,7 +174,7 @@ func (x *IPPort) ProtoReflect() protoreflect.Message {
 
 // Deprecated: Use IPPort.ProtoReflect.Descriptor instead.
 func (*IPPort) Descriptor() ([]byte, []int) {
-	return file_internal_machine_api_pb_common_proto_rawDescGZIP(), []int{1}
+	return file_internal_machine_api_pb_common_proto_rawDescGZIP(), []int{2}
 }
 
 func (x *IPPort) GetIp() *IP {
@@ -134,7 +203,7 @@ type IPPrefix struct {
 func (x *IPPrefix) Reset() {
 	*x = IPPrefix{}
 	if protoimpl.UnsafeEnabled {
-		mi := &file_internal_machine_api_pb_common_proto_msgTypes[2]
+		mi := &file_internal_machine_api_pb_common_proto_msgTypes[3]
 		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
 		ms.StoreMessageInfo(mi)
 	}
@@ -147,7 +216,7 @@ func (x *IPPrefix) String() string {
 func (*IPPrefix) ProtoMessage() {}
 
 func (x *IPPrefix) ProtoReflect() protoreflect.Message {
-	mi := &file_internal_machine_api_pb_common_proto_msgTypes[2]
+	mi := &file_internal_machine_api_pb_common_proto_msgTypes[3]
 	if protoimpl.UnsafeEnabled && x != nil {
 		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
 		if ms.LoadMessageInfo() == nil {
@@ -160,7 +229,7 @@ func (x *IPPrefix) ProtoReflect() protoreflect.Message {
 
 // Deprecated: Use IPPrefix.ProtoReflect.Descriptor instead.
 func (*IPPrefix) Descriptor() ([]byte, []int) {
-	return file_internal_machine_api_pb_common_proto_rawDescGZIP(), []int{2}
+	return file_internal_machine_api_pb_common_proto_rawDescGZIP(), []int{3}
 }
 
 func (x *IPPrefix) GetIp() *IP {
@@ -182,20 +251,28 @@ var File_internal_machine_api_pb_common_proto protoreflect.FileDescriptor
 var file_internal_machine_api_pb_common_proto_rawDesc = []byte{
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+	0x74, 0x6f, 0x33,
 }
 
 var (
@@ -210,20 +287,23 @@ func file_internal_machine_api_pb_common_proto_rawDescGZIP() []byte {
 	return file_internal_machine_api_pb_common_proto_rawDescData
 }
 
-var file_internal_machine_api_pb_common_proto_msgTypes = make([]protoimpl.MessageInfo, 3)
+var file_internal_machine_api_pb_common_proto_msgTypes = make([]protoimpl.MessageInfo, 4)
 var file_internal_machine_api_pb_common_proto_goTypes = []any{
-	(*IP)(nil),       // 0: api.IP
+	(*Metadata)(nil),      // 0: api.Metadata
-	(*IPPort)(nil),   // 1: api.IPPort
+	(*IP)(nil),            // 1: api.IP
-	(*IPPrefix)(nil), // 2: api.IPPrefix
+	(*IPPort)(nil),        // 2: api.IPPort
+	(*IPPrefix)(nil),      // 3: api.IPPrefix
+	(*status.Status)(nil), // 4: google.rpc.Status
 }
 var file_internal_machine_api_pb_common_proto_depIdxs = []int32{
-	0, // 0: api.IPPort.ip:type_name -> api.IP
+	4, // 0: api.Metadata.status:type_name -> google.rpc.Status
-	0, // 1: api.IPPrefix.ip:type_name -> api.IP
+	1, // 1: api.IPPort.ip:type_name -> api.IP
-	2, // [2:2] is the sub-list for method output_type
+	1, // 2: api.IPPrefix.ip:type_name -> api.IP
-	2, // [2:2] is the sub-list for method input_type
+	3, // [3:3] is the sub-list for method output_type
-	2, // [2:2] is the sub-list for extension type_name
+	3, // [3:3] is the sub-list for method input_type
-	2, // [2:2] is the sub-list for extension extendee
+	3, // [3:3] is the sub-list for extension type_name
-	0, // [0:2] is the sub-list for field type_name
+	3, // [3:3] is the sub-list for extension extendee
+	0, // [0:3] is the sub-list for field type_name
 }
 
 func init() { file_internal_machine_api_pb_common_proto_init() }
@@ -233,7 +313,7 @@ func file_internal_machine_api_pb_common_proto_init() {
 	}
 	if !protoimpl.UnsafeEnabled {
 		file_internal_machine_api_pb_common_proto_msgTypes[0].Exporter = func(v any, i int) any {
-			switch v := v.(*IP); i {
+			switch v := v.(*Metadata); i {
 			case 0:
 				return &v.state
 			case 1:
@@ -245,7 +325,7 @@ func file_internal_machine_api_pb_common_proto_init() {
 			}
 		}
 		file_internal_machine_api_pb_common_proto_msgTypes[1].Exporter = func(v any, i int) any {
-			switch v := v.(*IPPort); i {
+			switch v := v.(*IP); i {
 			case 0:
 				return &v.state
 			case 1:
@@ -257,6 +337,18 @@ func file_internal_machine_api_pb_common_proto_init() {
 			}
 		}
 		file_internal_machine_api_pb_common_proto_msgTypes[2].Exporter = func(v any, i int) any {
+			switch v := v.(*IPPort); i {
+			case 0:
+				return &v.state
+			case 1:
+				return &v.sizeCache
+			case 2:
+				return &v.unknownFields
+			default:
+				return nil
+			}
+		}
+		file_internal_machine_api_pb_common_proto_msgTypes[3].Exporter = func(v any, i int) any {
 			switch v := v.(*IPPrefix); i {
 			case 0:
 				return &v.state
@@ -275,7 +367,7 @@ func file_internal_machine_api_pb_common_proto_init() {
 			GoPackagePath: reflect.TypeOf(x{}).PkgPath(),
 			RawDescriptor: file_internal_machine_api_pb_common_proto_rawDesc,
 			NumEnums:      0,
-			NumMessages:   3,
+			NumMessages:   4,
 			NumExtensions: 0,
 			NumServices:   0,
 		},

internal/machine/api/pb/common.proto

@@ -4,6 +4,20 @@ package api;
 
 option go_package = "github.com/psviderski/uncloud/internal/machine/api/pb";
 
+// Vendored at internal/machine/api/vendor/google/rpc/status.proto.
+import "google/rpc/status.proto";
+
+// Common metadata message nested in all reply message types, injected by the gRPC proxy to provide information
+// about the machine that responded to the request.
+message Metadata {
+  // Address of the machine the response came from.
+  string machine = 1;
+  // error is set if the request to upstream failed. The rest of the response is undefined.
+  string error = 2;
+  // error as a gRPC Status message.
+  google.rpc.Status status = 3;
+}
+
 message IP {
   bytes ip = 1;
 }

internal/machine/api/vendor/google/rpc/status.proto

@@ -0,0 +1,49 @@
+// Copyright 2024 Google LLC
+//
+// 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.
+
+syntax = "proto3";
+
+package google.rpc;
+
+import "google/protobuf/any.proto";
+
+option cc_enable_arenas = true;
+option go_package = "google.golang.org/genproto/googleapis/rpc/status;status";
+option java_multiple_files = true;
+option java_outer_classname = "StatusProto";
+option java_package = "com.google.rpc";
+option objc_class_prefix = "RPC";
+
+// The `Status` type defines a logical error model that is suitable for
+// different programming environments, including REST APIs and RPC APIs. It is
+// used by [gRPC](https://github.com/grpc). Each `Status` message contains
+// three pieces of data: error code, error message, and error details.
+//
+// You can find out more about this error model and how to work with it in the
+// [API Design Guide](https://cloud.google.com/apis/design/errors).
+message Status {
+  // The status code, which should be an enum value of
+  // [google.rpc.Code][google.rpc.Code].
+  int32 code = 1;
+
+  // A developer-facing error message, which should be in English. Any
+  // user-facing error message should be localized and sent in the
+  // [google.rpc.Status.details][google.rpc.Status.details] field, or localized
+  // by the client.
+  string message = 2;
+
+  // A list of messages that carry the error details.  There is a common set of
+  // message types for APIs to use.
+  repeated google.protobuf.Any details = 3;
+}