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// 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.
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// 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
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// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
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// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

// Service exported by server reflection

syntax = "proto3";

package grpc.reflection.v1alpha;

service ServerReflection {
  // The reflection service is structured as a bidirectional stream, ensuring
  // all related requests go to a single server.
  rpc ServerReflectionInfo(stream ServerReflectionRequest)
      returns (stream ServerReflectionResponse);
}

// The message sent by the client when calling ServerReflectionInfo method.
message ServerReflectionRequest {
  string host = 1;
  // To use reflection service, the client should set one of the following
  // fields in message_request. The server distinguishes requests by their
  // defined field and then handles them using corresponding methods.
  oneof message_request {
    // Find a proto file by the file name.
    string file_by_filename = 3;

    // Find the proto file that declares the given fully-qualified symbol name.
    // This field should be a fully-qualified symbol name
    // (e.g. <package>.<service>[.<method>] or <package>.<type>).
    string file_containing_symbol = 4;

    // Find the proto file which defines an extension extending the given
    // message type with the given field number.
    ExtensionRequest file_containing_extension = 5;

    // Finds the tag numbers used by all known extensions of the given message
    // type, and appends them to ExtensionNumberResponse in an undefined order.
    // Its corresponding method is best-effort: it's not guaranteed that the
    // reflection service will implement this method, and it's not guaranteed
    // that this method will provide all extensions. Returns
    // StatusCode::UNIMPLEMENTED if it's not implemented.
    // This field should be a fully-qualified type name. The format is
    // <package>.<type>
    string all_extension_numbers_of_type = 6;

    // List the full names of registered services. The content will not be
    // checked.
    string list_services = 7;
  }
}

// The type name and extension number sent by the client when requesting
// file_containing_extension.
message ExtensionRequest {
  // Fully-qualified type name. The format should be <package>.<type>
  string containing_type = 1;
  int32 extension_number = 2;
}

// The message sent by the server to answer ServerReflectionInfo method.
message ServerReflectionResponse {
  string valid_host = 1;
  ServerReflectionRequest original_request = 2;
  // The server set one of the following fields accroding to the message_request
  // in the request.
  oneof message_response {
    // This message is used to answer file_by_filename, file_containing_symbol,
    // file_containing_extension requests with transitive dependencies. As
    // the repeated label is not allowed in oneof fields, we use a
    // FileDescriptorResponse message to encapsulate the repeated fields.
    // The reflection service is allowed to avoid sending FileDescriptorProtos
    // that were previously sent in response to earlier requests in the stream.
    FileDescriptorResponse file_descriptor_response = 4;

    // This message is used to answer all_extension_numbers_of_type requst.
    ExtensionNumberResponse all_extension_numbers_response = 5;

    // This message is used to answer list_services request.
    ListServiceResponse list_services_response = 6;

    // This message is used when an error occurs.
    ErrorResponse error_response = 7;
  }
}

// Serialized FileDescriptorProto messages sent by the server answering
// a file_by_filename, file_containing_symbol, or file_containing_extension
// request.
message FileDescriptorResponse {
  // Serialized FileDescriptorProto messages. We avoid taking a dependency on
  // descriptor.proto, which uses proto2 only features, by making them opaque
  // bytes instead.
  repeated bytes file_descriptor_proto = 1;
}

// A list of extension numbers sent by the server answering
// all_extension_numbers_of_type request.
message ExtensionNumberResponse {
  // Full name of the base type, including the package name. The format
  // is <package>.<type>
  string base_type_name = 1;
  repeated int32 extension_number = 2;
}

// A list of ServiceResponse sent by the server answering list_services request.
message ListServiceResponse {
  // The information of each service may be expanded in the future, so we use
  // ServiceResponse message to encapsulate it.
  repeated ServiceResponse service = 1;
}

// The information of a single service used by ListServiceResponse to answer
// list_services request.
message ServiceResponse {
  // Full name of a registered service, including its package name. The format
  // is <package>.<service>
  string name = 1;
}

// The error code and error message sent by the server when an error occurs.
message ErrorResponse {
  // This field uses the error codes defined in grpc::StatusCode.
  int32 error_code = 1;
  string error_message = 2;
}