dex/vendor/google.golang.org/grpc/reflection/serverreflection.go
2016-07-31 23:26:27 -07:00

395 lines
12 KiB
Go

/*
*
* Copyright 2016, Google Inc.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following disclaimer
* in the documentation and/or other materials provided with the
* distribution.
* * Neither the name of Google Inc. nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
*/
/*
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\n", err)
}
out, err := ioutil.ReadAll(r)
if err != nil {
return nil, fmt.Errorf("bad gzipped descriptor: %v\n", 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)
}
extT := reflect.TypeOf(extDesc.ExtensionType).Elem()
return s.fileDescForType(extT)
}
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 for 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.
enc, ok := meta.([]byte)
if !ok {
return nil, fmt.Errorf("invalid file descriptor for symbol: %v", name)
}
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
}
}
}