etcd/etcdctl/command/backup_command.go

94 lines
2.5 KiB
Go

/*
Copyright 2014 CoreOS, Inc.
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
package command
import (
"log"
"math/rand"
"os"
"path"
"time"
"github.com/coreos/etcd/Godeps/_workspace/src/github.com/codegangsta/cli"
"github.com/coreos/etcd/etcdserver"
"github.com/coreos/etcd/etcdserver/etcdserverpb"
"github.com/coreos/etcd/pkg/pbutil"
"github.com/coreos/etcd/snap"
"github.com/coreos/etcd/wal"
)
func NewBackupCommand() cli.Command {
return cli.Command{
Name: "backup",
Usage: "backup an etcd directory",
Flags: []cli.Flag{
cli.StringFlag{Name: "data-dir", Value: "", Usage: "Path to the etcd data dir"},
cli.StringFlag{Name: "backup-dir", Value: "", Usage: "Path to the backup dir"},
},
Action: handleBackup,
}
}
// handleBackup handles a request that intends to do a backup.
func handleBackup(c *cli.Context) {
srcSnap := path.Join(c.String("data-dir"), "snap")
destSnap := path.Join(c.String("backup-dir"), "snap")
srcWAL := path.Join(c.String("data-dir"), "wal")
destWAL := path.Join(c.String("backup-dir"), "wal")
if err := os.MkdirAll(destSnap, 0700); err != nil {
log.Fatalf("failed creating backup snapshot dir %v: %v", destSnap, err)
}
ss := snap.New(srcSnap)
snapshot, err := ss.Load()
if err != nil && err != snap.ErrNoSnapshot {
log.Fatal(err)
}
var index uint64
if snapshot != nil {
index = snapshot.Metadata.Index
newss := snap.New(destSnap)
if err := newss.SaveSnap(*snapshot); err != nil {
log.Fatal(err)
}
}
w, err := wal.OpenNotInUse(srcWAL, index)
if err != nil {
log.Fatal(err)
}
defer w.Close()
wmetadata, state, ents, err := w.ReadAll()
if err != nil {
log.Fatal(err)
}
var metadata etcdserverpb.Metadata
pbutil.MustUnmarshal(&metadata, wmetadata)
rand.Seed(time.Now().UnixNano())
metadata.NodeID = etcdserver.GenID()
metadata.ClusterID = etcdserver.GenID()
neww, err := wal.Create(destWAL, pbutil.MustMarshal(&metadata))
if err != nil {
log.Fatal(err)
}
defer neww.Close()
if err := neww.Save(state, ents); err != nil {
log.Fatal(err)
}
}