writeWampFlatBufferMessage function

int writeWampFlatBufferMessage(AbstractMessage message, Builder builder, { FlatBufferByteVectorReference? argumentsVector, FlatBufferByteVectorReference? argumentsKeywordsVector, FlatBufferByteVectorReference? payloadVector, bool includeApplicationPayload = true, List<DeferredFlatBufferVector>? deferredVectors, })

Write a model directly into the supplied builder. The caller finishes and freezes the root, so a guarded native-backed builder can use the same path. References reuse vectors from this build without reading the model payload. Ordinary Dart values still need CBOR construction and a vector write.

Implementation

int writeWampFlatBufferMessage(
  AbstractMessage message,
  fb.Builder builder, {
  FlatBufferByteVectorReference? argumentsVector,
  FlatBufferByteVectorReference? argumentsKeywordsVector,
  FlatBufferByteVectorReference? payloadVector,
  bool includeApplicationPayload = true,
  List<DeferredFlatBufferVector>? deferredVectors,
}) {
  final projection = projectWampFlatBufferMessage(message);
  final fields = projection.fields;
  final body = fields['msg'] as Map<String, Object?>;
  if (projection.dictionary != null) {
    fields['metadata'] = encodeWampFlatBufferCbor(
      projection.dictionary,
      maximumBytes: 1048576,
      stringDictionaryKeys: true,
    );
  }
  if (message is AbstractMessageWithPayload) {
    if (!includeApplicationPayload) {
      if (argumentsVector != null ||
          argumentsKeywordsVector != null ||
          payloadVector != null) {
        throw ArgumentError(
          'A control-only message cannot include application vectors',
        );
      }
      return writeWampFlatBufferFields(
        fields,
        builder,
        deferredVectors: deferredVectors,
      );
    }
    final lazy = message.toLazyPayload();
    final payload =
        payloadVector ??
        lazy.transparentBinaryPayload ??
        lazy.packedPayloadBytes;
    if (payload != null) {
      if (argumentsVector != null || argumentsKeywordsVector != null) {
        throw ArgumentError(
          'Transparent payload cannot also carry args/kwargs',
        );
      }
      body['payload'] = payload;
      return writeWampFlatBufferFields(
        fields,
        builder,
        deferredVectors: deferredVectors,
      );
    }
    if (argumentsVector != null) {
      body['args'] = argumentsVector;
    } else if (lazy.encoding == LazyPayloadEncoding.cbor &&
        lazy.argumentsBytes != null) {
      body['args'] = lazy.argumentsBytes;
    } else if (message.wireArguments != null) {
      body['args'] = encodeWampFlatBufferCbor(message.wireArguments);
    }
    if (argumentsKeywordsVector != null) {
      body['kwargs'] = argumentsKeywordsVector;
    } else if (lazy.encoding == LazyPayloadEncoding.cbor &&
        lazy.argumentsKeywordsBytes != null) {
      body['kwargs'] = lazy.argumentsKeywordsBytes;
    } else if (message.wireArgumentsKeywords != null) {
      body['kwargs'] = encodeWampFlatBufferCbor(message.wireArgumentsKeywords);
    }
  } else if (argumentsVector != null ||
      argumentsKeywordsVector != null ||
      payloadVector != null) {
    throw ArgumentError('This WAMP message has no payload vectors');
  }
  if (body['args'] case final Uint8List args) {
    validateFlatBufferCbor(args, rootMajor: 4);
  }
  if (body['kwargs'] case final Uint8List kwargs) {
    validateFlatBufferCbor(
      kwargs,
      rootMajor: 5,
      rootStringDictionaryKeys: true,
    );
  }
  return writeWampFlatBufferFields(
    fields,
    builder,
    deferredVectors: deferredVectors,
  );
}