field in query path not found

[gigo1980]

hi, i try to implement the following

syntax = "proto3";
option java_package = "com.polisource.service.stream.grpc";
//option java_multiple_files = true;
//option java_outer_classname = "StreamProto";

package streamservice;
import "google/api/annotations.proto";

message StreamItem {
    string identifier = 1;
    string headline = 2;

    Autor author = 3;
    StreamType type = 4;

    enum StreamType {
        FACEBOOK = 0;
        TWITTER = 1;
        EMAIL = 2;
    }
}

message GetStreamItemRequest{
    string id = 1;
}

message Autor {
    string identifier = 1;
    string author = 2;
}

service StreamService {
    rpc getItem (String) returns (StreamItem){
        option (google.api.http) = {
            get: "/v1/streams/{id}"
        };
    }
}

Any idea why it is missing the field?
it try to run

protoc -I/usr/local/include -I. \
  -I$GOPATH/src \
  -I$GOPATH/src/github.com/grpc-ecosystem/grpc-gateway/third_party/googleapis \
  --grpc-gateway_out=logtostderr=true:. \
  --proto_path=../service-stream/src/main/proto \
  ../service-stream/src/main/proto/Stream.proto

The reponse is: --grpc-gateway_out: no field "id" found in String

[gigo1980]

Ok it was my fault,

rpc method signature has to be rpc getItem (GetStreamItemRequest) returns (StreamItem)