Exemplo n.º 1
0
// estimateUnknownSize returns the expected bytes consumed by a given runtime.Unknown
// object with a nil RawJSON struct and the expected size of the provided buffer. The
// returned size will not be correct if RawJSOn is set on unk.
func estimateUnknownSize(unk *runtime.Unknown, byteSize uint64) uint64 {
	size := uint64(unk.Size())
	// protobuf uses 1 byte for the tag, a varint for the length of the array (at most 8 bytes - uint64 - here),
	// and the size of the array.
	size += 1 + 8 + byteSize
	return size
}
Exemplo n.º 2
0
// Encode serializes the provided object to the given writer.
func (s *Serializer) Encode(obj runtime.Object, w io.Writer) error {
	prefixSize := uint64(len(s.prefix))

	var unk runtime.Unknown
	switch t := obj.(type) {
	case *runtime.Unknown:
		estimatedSize := prefixSize + uint64(t.Size())
		data := make([]byte, estimatedSize)
		i, err := t.MarshalTo(data[prefixSize:])
		if err != nil {
			return err
		}
		copy(data, s.prefix)
		_, err = w.Write(data[:prefixSize+uint64(i)])
		return err
	default:
		kind := obj.GetObjectKind().GroupVersionKind()
		unk = runtime.Unknown{
			TypeMeta: runtime.TypeMeta{
				Kind:       kind.Kind,
				APIVersion: kind.GroupVersion().String(),
			},
		}
	}

	switch t := obj.(type) {
	case bufferedMarshaller:
		// this path performs a single allocation during write but requires the caller to implement
		// the more efficient Size and MarshalTo methods
		encodedSize := uint64(t.Size())
		estimatedSize := prefixSize + estimateUnknownSize(&unk, encodedSize)
		data := make([]byte, estimatedSize)

		i, err := unk.NestedMarshalTo(data[prefixSize:], t, encodedSize)
		if err != nil {
			return err
		}

		copy(data, s.prefix)

		_, err = w.Write(data[:prefixSize+uint64(i)])
		return err

	case proto.Marshaler:
		// this path performs extra allocations
		data, err := t.Marshal()
		if err != nil {
			return err
		}
		unk.Raw = data

		estimatedSize := prefixSize + uint64(unk.Size())
		data = make([]byte, estimatedSize)

		i, err := unk.MarshalTo(data[prefixSize:])
		if err != nil {
			return err
		}

		copy(data, s.prefix)

		_, err = w.Write(data[:prefixSize+uint64(i)])
		return err

	default:
		// TODO: marshal with a different content type and serializer (JSON for third party objects)
		return errNotMarshalable{reflect.TypeOf(obj)}
	}
}