proto: Add definition for ProcReceiveHook RPC

For the `ProcReceiveHook` to work we need to create a RPC which is
called by the `gitaly-hooks` binary. Before we create this RPC, let's
note the definition of the RPC in the `hook.proto` file.

In the following commits we'll define the client and the service
following this definition.

3 files changed, 327 insertions, 30 deletions

diff --git a/proto/go/gitalypb/hook.pb.go b/proto/go/gitalypb/hook.pb.go
index 1e2abca53..2d4ff64ec 100644
--- a/proto/go/gitalypb/hook.pb.go
+++ b/proto/go/gitalypb/hook.pb.go
@@ -788,6 +788,142 @@ func (*PackObjectsHookWithSidechannelResponse) Descriptor() ([]byte, []int) {
 	return file_hook_proto_rawDescGZIP(), []int{9}
 }
 
+// ProcReceiveHookRequest is the request for the ProcReceiveHook RPC.
+type ProcReceiveHookRequest struct {
+	state         protoimpl.MessageState
+	sizeCache     protoimpl.SizeCache
+	unknownFields protoimpl.UnknownFields
+
+	// repository is the repository the hook operates on. This field is unused
+	// currently since we gather all information from stdin.
+	Repository *Repository `protobuf:"bytes,1,opt,name=repository,proto3" json:"repository,omitempty"`
+	// environment_variables is the set of env variables to be passed to the RPC.
+	EnvironmentVariables []string `protobuf:"bytes,2,rep,name=environment_variables,json=environmentVariables,proto3" json:"environment_variables,omitempty"`
+	// stdin is a chunk of raw data which the hook receives.
+	Stdin []byte `protobuf:"bytes,3,opt,name=stdin,proto3" json:"stdin,omitempty"`
+}
+
+func (x *ProcReceiveHookRequest) Reset() {
+	*x = ProcReceiveHookRequest{}
+	if protoimpl.UnsafeEnabled {
+		mi := &file_hook_proto_msgTypes[10]
+		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+		ms.StoreMessageInfo(mi)
+	}
+}
+
+func (x *ProcReceiveHookRequest) String() string {
+	return protoimpl.X.MessageStringOf(x)
+}
+
+func (*ProcReceiveHookRequest) ProtoMessage() {}
+
+func (x *ProcReceiveHookRequest) ProtoReflect() protoreflect.Message {
+	mi := &file_hook_proto_msgTypes[10]
+	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 ProcReceiveHookRequest.ProtoReflect.Descriptor instead.
+func (*ProcReceiveHookRequest) Descriptor() ([]byte, []int) {
+	return file_hook_proto_rawDescGZIP(), []int{10}
+}
+
+func (x *ProcReceiveHookRequest) GetRepository() *Repository {
+	if x != nil {
+		return x.Repository
+	}
+	return nil
+}
+
+func (x *ProcReceiveHookRequest) GetEnvironmentVariables() []string {
+	if x != nil {
+		return x.EnvironmentVariables
+	}
+	return nil
+}
+
+func (x *ProcReceiveHookRequest) GetStdin() []byte {
+	if x != nil {
+		return x.Stdin
+	}
+	return nil
+}
+
+// ProcReceiveHookResponse is the response for the ProcReceiveHook RPC.
+type ProcReceiveHookResponse struct {
+	state         protoimpl.MessageState
+	sizeCache     protoimpl.SizeCache
+	unknownFields protoimpl.UnknownFields
+
+	// stdout is a chunk of raw data to be output to stdout of the hook.
+	Stdout []byte `protobuf:"bytes,1,opt,name=stdout,proto3" json:"stdout,omitempty"`
+	// stderr is a chunk of raw data to be output to stderr of the hook.
+	Stderr []byte `protobuf:"bytes,2,opt,name=stderr,proto3" json:"stderr,omitempty"`
+	// exit_status is the exit status that the hooks outputs, this dictates the
+	// success/failure of git-receive-pack(1).
+	ExitStatus *ExitStatus `protobuf:"bytes,3,opt,name=exit_status,json=exitStatus,proto3" json:"exit_status,omitempty"`
+}
+
+func (x *ProcReceiveHookResponse) Reset() {
+	*x = ProcReceiveHookResponse{}
+	if protoimpl.UnsafeEnabled {
+		mi := &file_hook_proto_msgTypes[11]
+		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+		ms.StoreMessageInfo(mi)
+	}
+}
+
+func (x *ProcReceiveHookResponse) String() string {
+	return protoimpl.X.MessageStringOf(x)
+}
+
+func (*ProcReceiveHookResponse) ProtoMessage() {}
+
+func (x *ProcReceiveHookResponse) ProtoReflect() protoreflect.Message {
+	mi := &file_hook_proto_msgTypes[11]
+	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 ProcReceiveHookResponse.ProtoReflect.Descriptor instead.
+func (*ProcReceiveHookResponse) Descriptor() ([]byte, []int) {
+	return file_hook_proto_rawDescGZIP(), []int{11}
+}
+
+func (x *ProcReceiveHookResponse) GetStdout() []byte {
+	if x != nil {
+		return x.Stdout
+	}
+	return nil
+}
+
+func (x *ProcReceiveHookResponse) GetStderr() []byte {
+	if x != nil {
+		return x.Stderr
+	}
+	return nil
+}
+
+func (x *ProcReceiveHookResponse) GetExitStatus() *ExitStatus {
+	if x != nil {
+		return x.ExitStatus
+	}
+	return nil
+}
+
 var File_hook_proto protoreflect.FileDescriptor
 
 var file_hook_proto_rawDesc = []byte{
@@ -899,8 +1035,26 @@ var file_hook_proto_rawDesc = []byte{
 	0x74, 0x65, 0x5f, 0x69, 0x70, 0x18, 0x07, 0x20, 0x01, 0x28, 0x09, 0x52, 0x08, 0x72, 0x65, 0x6d,
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@@ -934,6 +1088,12 @@ var file_hook_proto_rawDesc = []byte{
 	0x79, 0x2e, 0x50, 0x61, 0x63, 0x6b, 0x4f, 0x62, 0x6a, 0x65, 0x63, 0x74, 0x73, 0x48, 0x6f, 0x6f,
 	0x6b, 0x57, 0x69, 0x74, 0x68, 0x53, 0x69, 0x64, 0x65, 0x63, 0x68, 0x61, 0x6e, 0x6e, 0x65, 0x6c,
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@@ -953,7 +1113,7 @@ func file_hook_proto_rawDescGZIP() []byte {
 }
 
 var file_hook_proto_enumTypes = make([]protoimpl.EnumInfo, 1)
-var file_hook_proto_msgTypes = make([]protoimpl.MessageInfo, 10)
+var file_hook_proto_msgTypes = make([]protoimpl.MessageInfo, 12)
 var file_hook_proto_goTypes = []interface{}{
 	(ReferenceTransactionHookRequest_State)(0),     // 0: gitaly.ReferenceTransactionHookRequest.State
 	(*PreReceiveHookRequest)(nil),                  // 1: gitaly.PreReceiveHookRequest
@@ -966,35 +1126,41 @@ var file_hook_proto_goTypes = []interface{}{
 	(*ReferenceTransactionHookResponse)(nil),       // 8: gitaly.ReferenceTransactionHookResponse
 	(*PackObjectsHookWithSidechannelRequest)(nil),  // 9: gitaly.PackObjectsHookWithSidechannelRequest
 	(*PackObjectsHookWithSidechannelResponse)(nil), // 10: gitaly.PackObjectsHookWithSidechannelResponse
-	(*Repository)(nil),                             // 11: gitaly.Repository
-	(*ExitStatus)(nil),                             // 12: gitaly.ExitStatus
+	(*ProcReceiveHookRequest)(nil),                 // 11: gitaly.ProcReceiveHookRequest
+	(*ProcReceiveHookResponse)(nil),                // 12: gitaly.ProcReceiveHookResponse
+	(*Repository)(nil),                             // 13: gitaly.Repository
+	(*ExitStatus)(nil),                             // 14: gitaly.ExitStatus
 }
 var file_hook_proto_depIdxs = []int32{
-	11, // 0: gitaly.PreReceiveHookRequest.repository:type_name -> gitaly.Repository
-	12, // 1: gitaly.PreReceiveHookResponse.exit_status:type_name -> gitaly.ExitStatus
-	11, // 2: gitaly.PostReceiveHookRequest.repository:type_name -> gitaly.Repository
-	12, // 3: gitaly.PostReceiveHookResponse.exit_status:type_name -> gitaly.ExitStatus
-	11, // 4: gitaly.UpdateHookRequest.repository:type_name -> gitaly.Repository
-	12, // 5: gitaly.UpdateHookResponse.exit_status:type_name -> gitaly.ExitStatus
-	11, // 6: gitaly.ReferenceTransactionHookRequest.repository:type_name -> gitaly.Repository
+	13, // 0: gitaly.PreReceiveHookRequest.repository:type_name -> gitaly.Repository
+	14, // 1: gitaly.PreReceiveHookResponse.exit_status:type_name -> gitaly.ExitStatus
+	13, // 2: gitaly.PostReceiveHookRequest.repository:type_name -> gitaly.Repository
+	14, // 3: gitaly.PostReceiveHookResponse.exit_status:type_name -> gitaly.ExitStatus
+	13, // 4: gitaly.UpdateHookRequest.repository:type_name -> gitaly.Repository
+	14, // 5: gitaly.UpdateHookResponse.exit_status:type_name -> gitaly.ExitStatus
+	13, // 6: gitaly.ReferenceTransactionHookRequest.repository:type_name -> gitaly.Repository
 	0,  // 7: gitaly.ReferenceTransactionHookRequest.state:type_name -> gitaly.ReferenceTransactionHookRequest.State
-	12, // 8: gitaly.ReferenceTransactionHookResponse.exit_status:type_name -> gitaly.ExitStatus
-	11, // 9: gitaly.PackObjectsHookWithSidechannelRequest.repository:type_name -> gitaly.Repository
-	1,  // 10: gitaly.HookService.PreReceiveHook:input_type -> gitaly.PreReceiveHookRequest
-	3,  // 11: gitaly.HookService.PostReceiveHook:input_type -> gitaly.PostReceiveHookRequest
-	5,  // 12: gitaly.HookService.UpdateHook:input_type -> gitaly.UpdateHookRequest
-	7,  // 13: gitaly.HookService.ReferenceTransactionHook:input_type -> gitaly.ReferenceTransactionHookRequest
-	9,  // 14: gitaly.HookService.PackObjectsHookWithSidechannel:input_type -> gitaly.PackObjectsHookWithSidechannelRequest
-	2,  // 15: gitaly.HookService.PreReceiveHook:output_type -> gitaly.PreReceiveHookResponse
-	4,  // 16: gitaly.HookService.PostReceiveHook:output_type -> gitaly.PostReceiveHookResponse
-	6,  // 17: gitaly.HookService.UpdateHook:output_type -> gitaly.UpdateHookResponse
-	8,  // 18: gitaly.HookService.ReferenceTransactionHook:output_type -> gitaly.ReferenceTransactionHookResponse
-	10, // 19: gitaly.HookService.PackObjectsHookWithSidechannel:output_type -> gitaly.PackObjectsHookWithSidechannelResponse
-	15, // [15:20] is the sub-list for method output_type
-	10, // [10:15] is the sub-list for method input_type
-	10, // [10:10] is the sub-list for extension type_name
-	10, // [10:10] is the sub-list for extension extendee
-	0,  // [0:10] is the sub-list for field type_name
+	14, // 8: gitaly.ReferenceTransactionHookResponse.exit_status:type_name -> gitaly.ExitStatus
+	13, // 9: gitaly.PackObjectsHookWithSidechannelRequest.repository:type_name -> gitaly.Repository
+	13, // 10: gitaly.ProcReceiveHookRequest.repository:type_name -> gitaly.Repository
+	14, // 11: gitaly.ProcReceiveHookResponse.exit_status:type_name -> gitaly.ExitStatus
+	1,  // 12: gitaly.HookService.PreReceiveHook:input_type -> gitaly.PreReceiveHookRequest
+	3,  // 13: gitaly.HookService.PostReceiveHook:input_type -> gitaly.PostReceiveHookRequest
+	5,  // 14: gitaly.HookService.UpdateHook:input_type -> gitaly.UpdateHookRequest
+	7,  // 15: gitaly.HookService.ReferenceTransactionHook:input_type -> gitaly.ReferenceTransactionHookRequest
+	9,  // 16: gitaly.HookService.PackObjectsHookWithSidechannel:input_type -> gitaly.PackObjectsHookWithSidechannelRequest
+	11, // 17: gitaly.HookService.ProcReceiveHook:input_type -> gitaly.ProcReceiveHookRequest
+	2,  // 18: gitaly.HookService.PreReceiveHook:output_type -> gitaly.PreReceiveHookResponse
+	4,  // 19: gitaly.HookService.PostReceiveHook:output_type -> gitaly.PostReceiveHookResponse
+	6,  // 20: gitaly.HookService.UpdateHook:output_type -> gitaly.UpdateHookResponse
+	8,  // 21: gitaly.HookService.ReferenceTransactionHook:output_type -> gitaly.ReferenceTransactionHookResponse
+	10, // 22: gitaly.HookService.PackObjectsHookWithSidechannel:output_type -> gitaly.PackObjectsHookWithSidechannelResponse
+	12, // 23: gitaly.HookService.ProcReceiveHook:output_type -> gitaly.ProcReceiveHookResponse
+	18, // [18:24] is the sub-list for method output_type
+	12, // [12:18] is the sub-list for method input_type
+	12, // [12:12] is the sub-list for extension type_name
+	12, // [12:12] is the sub-list for extension extendee
+	0,  // [0:12] is the sub-list for field type_name
 }
 
 func init() { file_hook_proto_init() }
@@ -1125,6 +1291,30 @@ func file_hook_proto_init() {
 				return nil
 			}
 		}
+		file_hook_proto_msgTypes[10].Exporter = func(v interface{}, i int) interface{} {
+			switch v := v.(*ProcReceiveHookRequest); i {
+			case 0:
+				return &v.state
+			case 1:
+				return &v.sizeCache
+			case 2:
+				return &v.unknownFields
+			default:
+				return nil
+			}
+		}
+		file_hook_proto_msgTypes[11].Exporter = func(v interface{}, i int) interface{} {
+			switch v := v.(*ProcReceiveHookResponse); i {
+			case 0:
+				return &v.state
+			case 1:
+				return &v.sizeCache
+			case 2:
+				return &v.unknownFields
+			default:
+				return nil
+			}
+		}
 	}
 	type x struct{}
 	out := protoimpl.TypeBuilder{
@@ -1132,7 +1322,7 @@ func file_hook_proto_init() {
 			GoPackagePath: reflect.TypeOf(x{}).PkgPath(),
 			RawDescriptor: file_hook_proto_rawDesc,
 			NumEnums:      1,
-			NumMessages:   10,
+			NumMessages:   12,
 			NumExtensions: 0,
 			NumServices:   1,
 		},
diff --git a/proto/go/gitalypb/hook_grpc.pb.go b/proto/go/gitalypb/hook_grpc.pb.go
index 72c55af65..44007d38e 100644
--- a/proto/go/gitalypb/hook_grpc.pb.go
+++ b/proto/go/gitalypb/hook_grpc.pb.go
@@ -33,6 +33,11 @@ type HookServiceClient interface {
 	// PackObjectsHookWithSidechannel is an optimized version of PackObjectsHook that uses
 	// a unix socket side channel.
 	PackObjectsHookWithSidechannel(ctx context.Context, in *PackObjectsHookWithSidechannelRequest, opts ...grpc.CallOption) (*PackObjectsHookWithSidechannelResponse, error)
+	// ProcReceiveHook is a hook invoked by git-receive-pack(1) [1]. This hook is responsible
+	// for updating the relevant references and reporting the results back to receive-pack.
+	//
+	// [1]: https://git-scm.com/docs/githooks#proc-receive
+	ProcReceiveHook(ctx context.Context, opts ...grpc.CallOption) (HookService_ProcReceiveHookClient, error)
 }
 
 type hookServiceClient struct {
@@ -177,6 +182,37 @@ func (c *hookServiceClient) PackObjectsHookWithSidechannel(ctx context.Context,
 	return out, nil
 }
 
+func (c *hookServiceClient) ProcReceiveHook(ctx context.Context, opts ...grpc.CallOption) (HookService_ProcReceiveHookClient, error) {
+	stream, err := c.cc.NewStream(ctx, &HookService_ServiceDesc.Streams[4], "/gitaly.HookService/ProcReceiveHook", opts...)
+	if err != nil {
+		return nil, err
+	}
+	x := &hookServiceProcReceiveHookClient{stream}
+	return x, nil
+}
+
+type HookService_ProcReceiveHookClient interface {
+	Send(*ProcReceiveHookRequest) error
+	Recv() (*ProcReceiveHookResponse, error)
+	grpc.ClientStream
+}
+
+type hookServiceProcReceiveHookClient struct {
+	grpc.ClientStream
+}
+
+func (x *hookServiceProcReceiveHookClient) Send(m *ProcReceiveHookRequest) error {
+	return x.ClientStream.SendMsg(m)
+}
+
+func (x *hookServiceProcReceiveHookClient) Recv() (*ProcReceiveHookResponse, error) {
+	m := new(ProcReceiveHookResponse)
+	if err := x.ClientStream.RecvMsg(m); err != nil {
+		return nil, err
+	}
+	return m, nil
+}
+
 // HookServiceServer is the server API for HookService service.
 // All implementations must embed UnimplementedHookServiceServer
 // for forward compatibility
@@ -192,6 +228,11 @@ type HookServiceServer interface {
 	// PackObjectsHookWithSidechannel is an optimized version of PackObjectsHook that uses
 	// a unix socket side channel.
 	PackObjectsHookWithSidechannel(context.Context, *PackObjectsHookWithSidechannelRequest) (*PackObjectsHookWithSidechannelResponse, error)
+	// ProcReceiveHook is a hook invoked by git-receive-pack(1) [1]. This hook is responsible
+	// for updating the relevant references and reporting the results back to receive-pack.
+	//
+	// [1]: https://git-scm.com/docs/githooks#proc-receive
+	ProcReceiveHook(HookService_ProcReceiveHookServer) error
 	mustEmbedUnimplementedHookServiceServer()
 }
 
@@ -214,6 +255,9 @@ func (UnimplementedHookServiceServer) ReferenceTransactionHook(HookService_Refer
 func (UnimplementedHookServiceServer) PackObjectsHookWithSidechannel(context.Context, *PackObjectsHookWithSidechannelRequest) (*PackObjectsHookWithSidechannelResponse, error) {
 	return nil, status.Errorf(codes.Unimplemented, "method PackObjectsHookWithSidechannel not implemented")
 }
+func (UnimplementedHookServiceServer) ProcReceiveHook(HookService_ProcReceiveHookServer) error {
+	return status.Errorf(codes.Unimplemented, "method ProcReceiveHook not implemented")
+}
 func (UnimplementedHookServiceServer) mustEmbedUnimplementedHookServiceServer() {}
 
 // UnsafeHookServiceServer may be embedded to opt out of forward compatibility for this service.
@@ -344,6 +388,32 @@ func _HookService_PackObjectsHookWithSidechannel_Handler(srv interface{}, ctx co
 	return interceptor(ctx, in, info, handler)
 }
 
+func _HookService_ProcReceiveHook_Handler(srv interface{}, stream grpc.ServerStream) error {
+	return srv.(HookServiceServer).ProcReceiveHook(&hookServiceProcReceiveHookServer{stream})
+}
+
+type HookService_ProcReceiveHookServer interface {
+	Send(*ProcReceiveHookResponse) error
+	Recv() (*ProcReceiveHookRequest, error)
+	grpc.ServerStream
+}
+
+type hookServiceProcReceiveHookServer struct {
+	grpc.ServerStream
+}
+
+func (x *hookServiceProcReceiveHookServer) Send(m *ProcReceiveHookResponse) error {
+	return x.ServerStream.SendMsg(m)
+}
+
+func (x *hookServiceProcReceiveHookServer) Recv() (*ProcReceiveHookRequest, error) {
+	m := new(ProcReceiveHookRequest)
+	if err := x.ServerStream.RecvMsg(m); err != nil {
+		return nil, err
+	}
+	return m, nil
+}
+
 // HookService_ServiceDesc is the grpc.ServiceDesc for HookService service.
 // It's only intended for direct use with grpc.RegisterService,
 // and not to be introspected or modified (even as a copy)
@@ -380,6 +450,12 @@ var HookService_ServiceDesc = grpc.ServiceDesc{
 			ServerStreams: true,
 			ClientStreams: true,
 		},
+		{
+			StreamName:    "ProcReceiveHook",
+			Handler:       _HookService_ProcReceiveHook_Handler,
+			ServerStreams: true,
+			ClientStreams: true,
+		},
 	},
 	Metadata: "hook.proto",
 }
diff --git a/proto/hook.proto b/proto/hook.proto
index 1eb605477..87325a465 100644
--- a/proto/hook.proto
+++ b/proto/hook.proto
@@ -48,6 +48,15 @@ service HookService {
     };
   }
 
+  // ProcReceiveHook is a hook invoked by git-receive-pack(1) [1]. This hook is responsible
+  // for updating the relevant references and reporting the results back to receive-pack.
+  //
+  // [1]: https://git-scm.com/docs/githooks#proc-receive
+  rpc ProcReceiveHook(stream ProcReceiveHookRequest) returns (stream ProcReceiveHookResponse) {
+    option (op_type) = {
+      op: MUTATOR
+    };
+  };
 }
 
 // PreReceiveHookRequest ...
@@ -170,3 +179,25 @@ message PackObjectsHookWithSidechannelRequest {
 // PackObjectsHookWithSidechannelResponse ...
 message PackObjectsHookWithSidechannelResponse {
 }
+
+// ProcReceiveHookRequest is the request for the ProcReceiveHook RPC.
+message ProcReceiveHookRequest {
+  // repository is the repository the hook operates on. This field is unused
+  // currently since we gather all information from stdin.
+  Repository repository = 1 [(target_repository)=true];
+  // environment_variables is the set of env variables to be passed to the RPC.
+  repeated string environment_variables = 2;
+  // stdin is a chunk of raw data which the hook receives.
+  bytes stdin = 3;
+}
+
+// ProcReceiveHookResponse is the response for the ProcReceiveHook RPC.
+message ProcReceiveHookResponse {
+  // stdout is a chunk of raw data to be output to stdout of the hook.
+  bytes stdout = 1;
+  // stderr is a chunk of raw data to be output to stderr of the hook.
+  bytes stderr = 2;
+  // exit_status is the exit status that the hooks outputs, this dictates the
+  // success/failure of git-receive-pack(1).
+  ExitStatus exit_status = 3;
+}