etcd-io__etcd/rafthttp/message.go

package rafthttp

import (
	"encoding/binary"
	"io"

	"github.com/coreos/etcd/pkg/pbutil"
	"github.com/coreos/etcd/raft/raftpb"
)

// messageEncoder is a encoder that can encode all kinds of messages.
// It MUST be used with a paired messageDecoder.
type messageEncoder struct {
	w io.Writer
}

func (enc *messageEncoder) encode(m raftpb.Message) error {
	if err := binary.Write(enc.w, binary.BigEndian, uint64(m.Size())); err != nil {
		return err
	}
	_, err := enc.w.Write(pbutil.MustMarshal(&m))
	return err
}

// messageDecoder is a decoder that can decode all kinds of messages.
type messageDecoder struct {
	r io.Reader
}

func (dec *messageDecoder) decode() (raftpb.Message, error) {
	var m raftpb.Message
	var l uint64
	if err := binary.Read(dec.r, binary.BigEndian, &l); err != nil {
		return m, err
	}
	buf := make([]byte, int(l))
	if _, err := io.ReadFull(dec.r, buf); err != nil {
		return m, err
	}
	return m, m.Unmarshal(buf)
}