| /* |
| * |
| * Copyright 2016 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 reflection implements server reflection service. |
| |
| The service implemented is defined in: |
| https://github.com/grpc/grpc/blob/master/src/proto/grpc/reflection/v1alpha/reflection.proto. |
| |
| To register server reflection on a gRPC server: |
| import "google.golang.org/grpc/reflection" |
| |
| s := grpc.NewServer() |
| pb.RegisterYourOwnServer(s, &server{}) |
| |
| // Register reflection service on gRPC server. |
| reflection.Register(s) |
| |
| s.Serve(lis) |
| |
| */ |
| package reflection // import "google.golang.org/grpc/reflection" |
| |
| import ( |
| "bytes" |
| "compress/gzip" |
| "fmt" |
| "io" |
| "io/ioutil" |
| "reflect" |
| "strings" |
| |
| "github.com/golang/protobuf/proto" |
| dpb "github.com/golang/protobuf/protoc-gen-go/descriptor" |
| "google.golang.org/grpc" |
| "google.golang.org/grpc/codes" |
| rpb "google.golang.org/grpc/reflection/grpc_reflection_v1alpha" |
| ) |
| |
| type serverReflectionServer struct { |
| s *grpc.Server |
| // TODO add more cache if necessary |
| serviceInfo map[string]grpc.ServiceInfo // cache for s.GetServiceInfo() |
| } |
| |
| // Register registers the server reflection service on the given gRPC server. |
| func Register(s *grpc.Server) { |
| rpb.RegisterServerReflectionServer(s, &serverReflectionServer{ |
| s: s, |
| }) |
| } |
| |
| // protoMessage is used for type assertion on proto messages. |
| // Generated proto message implements function Descriptor(), but Descriptor() |
| // is not part of interface proto.Message. This interface is needed to |
| // call Descriptor(). |
| type protoMessage interface { |
| Descriptor() ([]byte, []int) |
| } |
| |
| // fileDescForType gets the file descriptor for the given type. |
| // The given type should be a proto message. |
| func (s *serverReflectionServer) fileDescForType(st reflect.Type) (*dpb.FileDescriptorProto, error) { |
| m, ok := reflect.Zero(reflect.PtrTo(st)).Interface().(protoMessage) |
| if !ok { |
| return nil, fmt.Errorf("failed to create message from type: %v", st) |
| } |
| enc, _ := m.Descriptor() |
| |
| return s.decodeFileDesc(enc) |
| } |
| |
| // decodeFileDesc does decompression and unmarshalling on the given |
| // file descriptor byte slice. |
| func (s *serverReflectionServer) decodeFileDesc(enc []byte) (*dpb.FileDescriptorProto, error) { |
| raw, err := decompress(enc) |
| if err != nil { |
| return nil, fmt.Errorf("failed to decompress enc: %v", err) |
| } |
| |
| fd := new(dpb.FileDescriptorProto) |
| if err := proto.Unmarshal(raw, fd); err != nil { |
| return nil, fmt.Errorf("bad descriptor: %v", err) |
| } |
| return fd, nil |
| } |
| |
| // decompress does gzip decompression. |
| func decompress(b []byte) ([]byte, error) { |
| r, err := gzip.NewReader(bytes.NewReader(b)) |
| if err != nil { |
| return nil, fmt.Errorf("bad gzipped descriptor: %v", err) |
| } |
| out, err := ioutil.ReadAll(r) |
| if err != nil { |
| return nil, fmt.Errorf("bad gzipped descriptor: %v", err) |
| } |
| return out, nil |
| } |
| |
| func (s *serverReflectionServer) typeForName(name string) (reflect.Type, error) { |
| pt := proto.MessageType(name) |
| if pt == nil { |
| return nil, fmt.Errorf("unknown type: %q", name) |
| } |
| st := pt.Elem() |
| |
| return st, nil |
| } |
| |
| func (s *serverReflectionServer) fileDescContainingExtension(st reflect.Type, ext int32) (*dpb.FileDescriptorProto, error) { |
| m, ok := reflect.Zero(reflect.PtrTo(st)).Interface().(proto.Message) |
| if !ok { |
| return nil, fmt.Errorf("failed to create message from type: %v", st) |
| } |
| |
| var extDesc *proto.ExtensionDesc |
| for id, desc := range proto.RegisteredExtensions(m) { |
| if id == ext { |
| extDesc = desc |
| break |
| } |
| } |
| |
| if extDesc == nil { |
| return nil, fmt.Errorf("failed to find registered extension for extension number %v", ext) |
| } |
| |
| return s.decodeFileDesc(proto.FileDescriptor(extDesc.Filename)) |
| } |
| |
| func (s *serverReflectionServer) allExtensionNumbersForType(st reflect.Type) ([]int32, error) { |
| m, ok := reflect.Zero(reflect.PtrTo(st)).Interface().(proto.Message) |
| if !ok { |
| return nil, fmt.Errorf("failed to create message from type: %v", st) |
| } |
| |
| exts := proto.RegisteredExtensions(m) |
| out := make([]int32, 0, len(exts)) |
| for id := range exts { |
| out = append(out, id) |
| } |
| return out, nil |
| } |
| |
| // fileDescEncodingByFilename finds the file descriptor for given filename, |
| // does marshalling on it and returns the marshalled result. |
| func (s *serverReflectionServer) fileDescEncodingByFilename(name string) ([]byte, error) { |
| enc := proto.FileDescriptor(name) |
| if enc == nil { |
| return nil, fmt.Errorf("unknown file: %v", name) |
| } |
| fd, err := s.decodeFileDesc(enc) |
| if err != nil { |
| return nil, err |
| } |
| return proto.Marshal(fd) |
| } |
| |
| // serviceMetadataForSymbol finds the metadata for name in s.serviceInfo. |
| // name should be a service name or a method name. |
| func (s *serverReflectionServer) serviceMetadataForSymbol(name string) (interface{}, error) { |
| if s.serviceInfo == nil { |
| s.serviceInfo = s.s.GetServiceInfo() |
| } |
| |
| // Check if it's a service name. |
| if info, ok := s.serviceInfo[name]; ok { |
| return info.Metadata, nil |
| } |
| |
| // Check if it's a method name. |
| pos := strings.LastIndex(name, ".") |
| // Not a valid method name. |
| if pos == -1 { |
| return nil, fmt.Errorf("unknown symbol: %v", name) |
| } |
| |
| info, ok := s.serviceInfo[name[:pos]] |
| // Substring before last "." is not a service name. |
| if !ok { |
| return nil, fmt.Errorf("unknown symbol: %v", name) |
| } |
| |
| // Search the method name in info.Methods. |
| var found bool |
| for _, m := range info.Methods { |
| if m.Name == name[pos+1:] { |
| found = true |
| break |
| } |
| } |
| if found { |
| return info.Metadata, nil |
| } |
| |
| return nil, fmt.Errorf("unknown symbol: %v", name) |
| } |
| |
| // fileDescEncodingContainingSymbol finds the file descriptor containing the given symbol, |
| // does marshalling on it and returns the marshalled result. |
| // The given symbol can be a type, a service or a method. |
| func (s *serverReflectionServer) fileDescEncodingContainingSymbol(name string) ([]byte, error) { |
| var ( |
| fd *dpb.FileDescriptorProto |
| ) |
| // Check if it's a type name. |
| if st, err := s.typeForName(name); err == nil { |
| fd, err = s.fileDescForType(st) |
| if err != nil { |
| return nil, err |
| } |
| } else { // Check if it's a service name or a method name. |
| meta, err := s.serviceMetadataForSymbol(name) |
| |
| // Metadata not found. |
| if err != nil { |
| return nil, err |
| } |
| |
| // Metadata not valid. |
| fileNameForMeta, ok := meta.(string) |
| if !ok { |
| return nil, fmt.Errorf("invalid file descriptor for symbol: %v", name) |
| } |
| |
| enc := proto.FileDescriptor(fileNameForMeta) |
| fd, err = s.decodeFileDesc(enc) |
| if err != nil { |
| return nil, err |
| } |
| } |
| |
| return proto.Marshal(fd) |
| } |
| |
| // fileDescEncodingContainingExtension finds the file descriptor containing given extension, |
| // does marshalling on it and returns the marshalled result. |
| func (s *serverReflectionServer) fileDescEncodingContainingExtension(typeName string, extNum int32) ([]byte, error) { |
| st, err := s.typeForName(typeName) |
| if err != nil { |
| return nil, err |
| } |
| fd, err := s.fileDescContainingExtension(st, extNum) |
| if err != nil { |
| return nil, err |
| } |
| return proto.Marshal(fd) |
| } |
| |
| // allExtensionNumbersForTypeName returns all extension numbers for the given type. |
| func (s *serverReflectionServer) allExtensionNumbersForTypeName(name string) ([]int32, error) { |
| st, err := s.typeForName(name) |
| if err != nil { |
| return nil, err |
| } |
| extNums, err := s.allExtensionNumbersForType(st) |
| if err != nil { |
| return nil, err |
| } |
| return extNums, nil |
| } |
| |
| // ServerReflectionInfo is the reflection service handler. |
| func (s *serverReflectionServer) ServerReflectionInfo(stream rpb.ServerReflection_ServerReflectionInfoServer) error { |
| for { |
| in, err := stream.Recv() |
| if err == io.EOF { |
| return nil |
| } |
| if err != nil { |
| return err |
| } |
| |
| out := &rpb.ServerReflectionResponse{ |
| ValidHost: in.Host, |
| OriginalRequest: in, |
| } |
| switch req := in.MessageRequest.(type) { |
| case *rpb.ServerReflectionRequest_FileByFilename: |
| b, err := s.fileDescEncodingByFilename(req.FileByFilename) |
| if err != nil { |
| out.MessageResponse = &rpb.ServerReflectionResponse_ErrorResponse{ |
| ErrorResponse: &rpb.ErrorResponse{ |
| ErrorCode: int32(codes.NotFound), |
| ErrorMessage: err.Error(), |
| }, |
| } |
| } else { |
| out.MessageResponse = &rpb.ServerReflectionResponse_FileDescriptorResponse{ |
| FileDescriptorResponse: &rpb.FileDescriptorResponse{FileDescriptorProto: [][]byte{b}}, |
| } |
| } |
| case *rpb.ServerReflectionRequest_FileContainingSymbol: |
| b, err := s.fileDescEncodingContainingSymbol(req.FileContainingSymbol) |
| if err != nil { |
| out.MessageResponse = &rpb.ServerReflectionResponse_ErrorResponse{ |
| ErrorResponse: &rpb.ErrorResponse{ |
| ErrorCode: int32(codes.NotFound), |
| ErrorMessage: err.Error(), |
| }, |
| } |
| } else { |
| out.MessageResponse = &rpb.ServerReflectionResponse_FileDescriptorResponse{ |
| FileDescriptorResponse: &rpb.FileDescriptorResponse{FileDescriptorProto: [][]byte{b}}, |
| } |
| } |
| case *rpb.ServerReflectionRequest_FileContainingExtension: |
| typeName := req.FileContainingExtension.ContainingType |
| extNum := req.FileContainingExtension.ExtensionNumber |
| b, err := s.fileDescEncodingContainingExtension(typeName, extNum) |
| if err != nil { |
| out.MessageResponse = &rpb.ServerReflectionResponse_ErrorResponse{ |
| ErrorResponse: &rpb.ErrorResponse{ |
| ErrorCode: int32(codes.NotFound), |
| ErrorMessage: err.Error(), |
| }, |
| } |
| } else { |
| out.MessageResponse = &rpb.ServerReflectionResponse_FileDescriptorResponse{ |
| FileDescriptorResponse: &rpb.FileDescriptorResponse{FileDescriptorProto: [][]byte{b}}, |
| } |
| } |
| case *rpb.ServerReflectionRequest_AllExtensionNumbersOfType: |
| extNums, err := s.allExtensionNumbersForTypeName(req.AllExtensionNumbersOfType) |
| if err != nil { |
| out.MessageResponse = &rpb.ServerReflectionResponse_ErrorResponse{ |
| ErrorResponse: &rpb.ErrorResponse{ |
| ErrorCode: int32(codes.NotFound), |
| ErrorMessage: err.Error(), |
| }, |
| } |
| } else { |
| out.MessageResponse = &rpb.ServerReflectionResponse_AllExtensionNumbersResponse{ |
| AllExtensionNumbersResponse: &rpb.ExtensionNumberResponse{ |
| BaseTypeName: req.AllExtensionNumbersOfType, |
| ExtensionNumber: extNums, |
| }, |
| } |
| } |
| case *rpb.ServerReflectionRequest_ListServices: |
| if s.serviceInfo == nil { |
| s.serviceInfo = s.s.GetServiceInfo() |
| } |
| serviceResponses := make([]*rpb.ServiceResponse, 0, len(s.serviceInfo)) |
| for n := range s.serviceInfo { |
| serviceResponses = append(serviceResponses, &rpb.ServiceResponse{ |
| Name: n, |
| }) |
| } |
| out.MessageResponse = &rpb.ServerReflectionResponse_ListServicesResponse{ |
| ListServicesResponse: &rpb.ListServiceResponse{ |
| Service: serviceResponses, |
| }, |
| } |
| default: |
| return grpc.Errorf(codes.InvalidArgument, "invalid MessageRequest: %v", in.MessageRequest) |
| } |
| |
| if err := stream.Send(out); err != nil { |
| return err |
| } |
| } |
| } |