grpc/extensions/reflection/proto_server_reflection.cc

/*
 *
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 * modification, are permitted provided that the following conditions are
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 *
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 * notice, this list of conditions and the following disclaimer.
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 * copyright notice, this list of conditions and the following disclaimer
 * in the documentation and/or other materials provided with the
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#include <iostream>
#include <memory>
#include <string>
#include <vector>

#include <google/protobuf/descriptor.h>
#include <google/protobuf/descriptor.pb.h>
#include <grpc++/grpc++.h>

#include "reflection/proto_server_reflection.h"

using grpc::Status;
using grpc::StatusCode;
using google::protobuf::MethodDescriptor;
using google::protobuf::ServiceDescriptor;
using google::protobuf::Descriptor;
using google::protobuf::FileDescriptor;
using google::protobuf::FieldDescriptor;
using google::protobuf::DescriptorPool;
using google::protobuf::FileDescriptorProto;
using grpc::reflection::v1alpha::ServerReflectionRequest;
using grpc::reflection::v1alpha::ExtensionRequest;
using grpc::reflection::v1alpha::ServerReflectionResponse;
using grpc::reflection::v1alpha::ListServiceResponse;
using grpc::reflection::v1alpha::ServiceResponse;
using grpc::reflection::v1alpha::ExtensionNumberResponse;
using grpc::reflection::v1alpha::ErrorResponse;
using grpc::reflection::v1alpha::FileDescriptorResponse;

namespace grpc {

ProtoServerReflection::ProtoServerReflection()
    : descriptor_pool_(DescriptorPool::generated_pool()) {}

void ProtoServerReflection::SetServiceList(
    const std::vector<grpc::string>* services) {
  services_ = services;
}

Status ProtoServerReflection::ServerReflectionInfo(
    ServerContext* context,
    ServerReaderWriter<ServerReflectionResponse, ServerReflectionRequest>*
        stream) {
  ServerReflectionRequest request;
  ServerReflectionResponse response;
  Status status;
  while (stream->Read(&request)) {
    switch (request.message_request_case()) {
      case ServerReflectionRequest::MessageRequestCase::kFileByFilename:
        status = GetFileByName(context, request.file_by_filename(), &response);
        break;
      case ServerReflectionRequest::MessageRequestCase::kFileContainingSymbol:
        status = GetFileContainingSymbol(
            context, request.file_containing_symbol(), &response);
        break;
      case ServerReflectionRequest::MessageRequestCase::
          kFileContainingExtension:
        status = GetFileContainingExtension(
            context, &request.file_containing_extension(), &response);
        break;
      case ServerReflectionRequest::MessageRequestCase::
          kAllExtensionNumbersOfType:
        status = GetAllExtensionNumbers(
            context, request.all_extension_numbers_of_type(),
            response.mutable_all_extension_numbers_response());
        break;
      case ServerReflectionRequest::MessageRequestCase::kListServices:
        status =
            ListService(context, response.mutable_list_services_response());
        break;
      default:
        status = Status(StatusCode::UNIMPLEMENTED, "");
    }

    response.set_valid_host(request.host());
    response.set_allocated_original_request(
        new ServerReflectionRequest(request));
    stream->Write(response);
  }

  return Status::OK;
}

void ProtoServerReflection::FillErrorResponse(Status* status,
                                              ErrorResponse* error_response) {
  error_response->set_error_code(status->error_code());
  error_response->set_error_message(status->error_message());
}

Status ProtoServerReflection::ListService(ServerContext* context,
                                          ListServiceResponse* response) {
  if (services_ == nullptr) {
    return Status(StatusCode::NOT_FOUND, "Services not found.");
  }
  for (auto it = services_->begin(); it != services_->end(); ++it) {
    ServiceResponse* service_response = response->add_service();
    service_response->set_name(*it);
  }
  return Status::OK;
}

Status ProtoServerReflection::GetFileByName(
    ServerContext* context, const grpc::string& filename,
    ServerReflectionResponse* response) {
  if (descriptor_pool_ == nullptr) {
    return Status::CANCELLED;
  }

  const FileDescriptor* file_desc = descriptor_pool_->FindFileByName(filename);
  if (file_desc == nullptr) {
    return Status(StatusCode::NOT_FOUND, "File not found.");
  }
  FillFileDescriptorProtoResponse(file_desc, response);
  return Status::OK;
}

Status ProtoServerReflection::GetFileContainingSymbol(
    ServerContext* context, const grpc::string& symbol,
    ServerReflectionResponse* response) {
  if (descriptor_pool_ == nullptr) {
    return Status::CANCELLED;
  }

  const FileDescriptor* file_desc =
      descriptor_pool_->FindFileContainingSymbol(symbol);
  if (file_desc == nullptr) {
    return Status(StatusCode::NOT_FOUND, "Symbol not found.");
  }
  FillFileDescriptorProtoResponse(file_desc, response);
  return Status::OK;
}

Status ProtoServerReflection::GetFileContainingExtension(
    ServerContext* context, const ExtensionRequest* request,
    ServerReflectionResponse* response) {
  if (descriptor_pool_ == nullptr) {
    return Status::CANCELLED;
  }

  const Descriptor* desc =
      descriptor_pool_->FindMessageTypeByName(request->containing_type());
  if (desc == nullptr) {
    return Status(StatusCode::NOT_FOUND, "Type not found.");
  }

  const FieldDescriptor* field_desc = descriptor_pool_->FindExtensionByNumber(
      desc, request->extension_number());
  if (field_desc == nullptr) {
    return Status(StatusCode::NOT_FOUND, "Extension not found.");
  }
  FillFileDescriptorProtoResponse(field_desc->file(), response);
  return Status::OK;
}

Status ProtoServerReflection::GetAllExtensionNumbers(
    ServerContext* context, const grpc::string& type,
    ExtensionNumberResponse* response) {
  if (descriptor_pool_ == nullptr) {
    return Status::CANCELLED;
  }

  const Descriptor* desc = descriptor_pool_->FindMessageTypeByName(type);
  if (desc == nullptr) {
    return Status(StatusCode::NOT_FOUND, "Type not found.");
  }

  std::vector<const FieldDescriptor*> extensions;
  descriptor_pool_->FindAllExtensions(desc, &extensions);
  for (auto extension : extensions) {
    response->add_extension_number(extension->number());
  }
  response->set_base_type_name(type);
  return Status::OK;
}

void ProtoServerReflection::FillFileDescriptorProtoResponse(
    const FileDescriptor* file_desc, ServerReflectionResponse* response) {
  FileDescriptorProto file_desc_proto;
  grpc::string data;
  file_desc->CopyTo(&file_desc_proto);
  file_desc_proto.SerializeToString(&data);
  response->mutable_file_descriptor_response()->add_file_descriptor_proto(data);
}

}  // namespace grpc