influxdb/snapshot_request.go

71 lines
1.6 KiB
Go

package raft
import (
"code.google.com/p/goprotobuf/proto"
"github.com/goraft/raft/protobuf"
"io"
"io/ioutil"
)
// The request sent to a server to start from the snapshot.
type SnapshotRequest struct {
LeaderName string
LastIndex uint64
LastTerm uint64
}
//------------------------------------------------------------------------------
//
// Constructors
//
//------------------------------------------------------------------------------
// Creates a new Snapshot request.
func newSnapshotRequest(leaderName string, snapshot *Snapshot) *SnapshotRequest {
return &SnapshotRequest{
LeaderName: leaderName,
LastIndex: snapshot.LastIndex,
LastTerm: snapshot.LastTerm,
}
}
// Encodes the SnapshotRequest to a buffer. Returns the number of bytes
// written and any error that may have occurred.
func (req *SnapshotRequest) encode(w io.Writer) (int, error) {
pb := &protobuf.ProtoSnapshotRequest{
LeaderName: proto.String(req.LeaderName),
LastIndex: proto.Uint64(req.LastIndex),
LastTerm: proto.Uint64(req.LastTerm),
}
p, err := proto.Marshal(pb)
if err != nil {
return -1, err
}
return w.Write(p)
}
// Decodes the SnapshotRequest from a buffer. Returns the number of bytes read and
// any error that occurs.
func (req *SnapshotRequest) decode(r io.Reader) (int, error) {
data, err := ioutil.ReadAll(r)
if err != nil {
return 0, err
}
totalBytes := len(data)
pb := &protobuf.ProtoSnapshotRequest{}
if err := proto.Unmarshal(data, pb); err != nil {
return -1, err
}
req.LeaderName = pb.GetLeaderName()
req.LastIndex = pb.GetLastIndex()
req.LastTerm = pb.GetLastTerm()
return totalBytes, nil
}