使用jsonpb解组自定义类型

Question

What's the best way to convert this json object to protobuf?

JSON:

{
  "name": "test",
  "_list": {
    "some1": { "value": 1 },
    "some2": [
      { "value": 2 },
      { "value": 3 },
    ]
  }
}

Proto:

message Something {
     string name = 1;
     message ListType {
       repeated string = 1;
     }
     map<string, ListType> _list = 2;
   }

Without having the _list in the message I would use jsonpb.Unmarsal, but I can't think of a way to define the Unmarshaler interface on a type that is generated in a diff package.

I also thought of having _list as a Any (json.RawMessage) and handle it after the Unmarshal (but can't make this to work; err message: Any JSON doesn't have '@type')

Answer 1

With _list being inconsistent (not just a list of strings/map of values/etc) and you mentioning you looked into using Any you could consider making your message:

message Something { string name = 1; google.protobuf.Struct _list = 2; }

https://github.com/golang/protobuf/blob/master/ptypes/struct/struct.proto

With that you can marshal/unmarshal json to/from proto messages using github.com/golang/protobuf/jsonpb which is actually designed for use with the grpc gateway but you can use it too