About typeConverter

[zgid123]

Hi, I checked the typeConverter example, we have TimestampString is extended from Date class, so when the mapper runs, those code lines will be skipped because the TimestampString is isDateConstructor. It won't run the function getMapping to get the correct mapping from mapper.

        let hasSameIdentifier =
            !isPrimitiveConstructor(destinationMemberIdentifier) &&
            !isDateConstructor(destinationMemberIdentifier) &&
            !isPrimitiveConstructor(sourceMemberIdentifier) &&
            !isDateConstructor(sourceMemberIdentifier) &&
            sourceMemberIdentifier === destinationMemberIdentifier;

        if (hasSameIdentifier) {
            // at this point, we have a same identifier that aren't primitive or date
            // we then check if there is a mapping created for this identifier
            hasSameIdentifier = !getMapping(
                mapper,
                sourceMemberIdentifier as MetadataIdentifier,
                destinationMemberIdentifier as MetadataIdentifier,
                true
            );
        }

I am working with Timestamp of google protobuf (google-protobuf/google/protobuf/timestamp_pb), to pass it to the gRPC, we need to do Timestamp.fromDate(new Date()).toObject(), the object's structure is { seconds: number; nanos: number; }.

I don't wanna config mapping for this structure and wanna pass to typeConverter like this

class GrpcTimestamp {
  nanos: number;
  seconds: number;
}

createMap(mapper, A, B, typeConverter(GrpcTimestamp, Date, (grpcTimestamp) => {
  const timestamp = new Timestamp();
  const { nanos, seconds } = data;

  timestamp.setNanos(nanos);
  timestamp.setSeconds(seconds);

  return timestamp.toDate();
});

But the hasSameIdentifier above will be true, and the library will throw error. Don't you think we should have a function or an option to make the hasSameIdentifier to be false with the class GrpcTimestamp? Or do we have a workaround to make it? Because I wanna reuse the logic to convert all GrpcTimestamp to Date.

I researched the code and couldn't find a way. Because maybe I will have some classes to work like that in the future and wanna do the typeConverter like that. Currently, I extend the GrpcTimestamp from Date to do the trick.

If we already have a solution, please help.

Thanks.

[zgid123]

Actually, the trick is not worked 😂

[zgid123]

I just realized that I debugged in wrong place. I will update the status of this discussion later. Currently the function getMapping will throw error

Error: Mapping is not found for class GrpcTimestamp extends Date {
    nanos;
    seconds;
} and function Date() { [native code] }

[zgid123]

after debugging, I found out that it was my mistake when using the typeConverter

export function grpcTimestampToDate(data: GrpcTimestamp): Date {
  const timestamp = new Timestamp();
  const { nanos, seconds } = data;

  timestamp.setNanos(nanos);
  timestamp.setSeconds(seconds.low);

  return timestamp.toDate();
}

createMap(
  mapper,
  GrpcVM,
  VM,
  grpcTimestampToDateConverter,
);

it must be

createMap(
  mapper,
  GrpcVM,
  VM,
  grpcTimestampToDateConverter(),
);

I have two functions like that, one function I used correctly, but this one not 😂

[nartc]

Hey @zgid123, thanks for the discussion and sorry for the late reply. I halted my OSS work while I was on vacation.

I agree that isDateConstructor() check is problematic there. Hm...I'll think more about it.

Did you solve your problem?

[zgid123]

yup, it was just my mistake when using wrapper function grpcTimestampToDateConverter, that was the reason the log raised the error. So no problem with the current logic.

Thanks for your rely.