seaweedfs/weed/shell/command_fs_meta_save.go
2020-02-25 22:23:59 -08:00

180 lines
4.5 KiB
Go

package shell
import (
"flag"
"fmt"
"io"
"os"
"sync"
"sync/atomic"
"time"
"github.com/golang/protobuf/proto"
"github.com/chrislusf/seaweedfs/weed/filer2"
"github.com/chrislusf/seaweedfs/weed/pb/filer_pb"
"github.com/chrislusf/seaweedfs/weed/util"
)
func init() {
Commands = append(Commands, &commandFsMetaSave{})
}
type commandFsMetaSave struct {
}
func (c *commandFsMetaSave) Name() string {
return "fs.meta.save"
}
func (c *commandFsMetaSave) Help() string {
return `save all directory and file meta data to a local file for metadata backup.
fs.meta.save / # save from the root
fs.meta.save -v -o t.meta / # save from the root, output to t.meta file.
fs.meta.save /path/to/save # save from the directory /path/to/save
fs.meta.save . # save from current directory
fs.meta.save # save from current directory
The meta data will be saved into a local <filer_host>-<port>-<time>.meta file.
These meta data can be later loaded by fs.meta.load command,
This assumes there are no deletions, so this is different from taking a snapshot.
`
}
func (c *commandFsMetaSave) Do(args []string, commandEnv *CommandEnv, writer io.Writer) (err error) {
fsMetaSaveCommand := flag.NewFlagSet(c.Name(), flag.ContinueOnError)
verbose := fsMetaSaveCommand.Bool("v", false, "print out each processed files")
outputFileName := fsMetaSaveCommand.String("o", "", "output the meta data to this file")
if err = fsMetaSaveCommand.Parse(args); err != nil {
return nil
}
filerServer, filerPort, path, parseErr := commandEnv.parseUrl(findInputDirectory(fsMetaSaveCommand.Args()))
if parseErr != nil {
return parseErr
}
t := time.Now()
fileName := *outputFileName
if fileName == "" {
fileName = fmt.Sprintf("%s-%d-%4d%02d%02d-%02d%02d%02d.meta",
filerServer, filerPort, t.Year(), t.Month(), t.Day(), t.Hour(), t.Minute(), t.Second())
}
dst, openErr := os.OpenFile(fileName, os.O_WRONLY|os.O_CREATE|os.O_TRUNC, 0644)
if openErr != nil {
return fmt.Errorf("failed to create file %s: %v", fileName, openErr)
}
defer dst.Close()
var wg sync.WaitGroup
wg.Add(1)
outputChan := make(chan []byte, 1024)
go func() {
sizeBuf := make([]byte, 4)
for b := range outputChan {
util.Uint32toBytes(sizeBuf, uint32(len(b)))
dst.Write(sizeBuf)
dst.Write(b)
}
wg.Done()
}()
var dirCount, fileCount uint64
err = doTraverseBFS(writer, commandEnv.getFilerClient(filerServer, filerPort), filer2.FullPath(path), func(parentPath filer2.FullPath, entry *filer_pb.Entry) {
protoMessage := &filer_pb.FullEntry{
Dir: string(parentPath),
Entry: entry,
}
bytes, err := proto.Marshal(protoMessage)
if err != nil {
fmt.Fprintf(writer, "marshall error: %v\n", err)
return
}
outputChan <- bytes
if entry.IsDirectory {
atomic.AddUint64(&dirCount, 1)
} else {
atomic.AddUint64(&fileCount, 1)
}
if *verbose {
println(parentPath.Child(entry.Name))
}
})
close(outputChan)
wg.Wait()
if err == nil {
fmt.Fprintf(writer, "total %d directories, %d files\n", dirCount, fileCount)
fmt.Fprintf(writer, "meta data for http://%s:%d%s is saved to %s\n", filerServer, filerPort, path, fileName)
}
return err
}
func doTraverseBFS(writer io.Writer, filerClient filer2.FilerClient, parentPath filer2.FullPath, fn func(parentPath filer2.FullPath, entry *filer_pb.Entry)) (err error) {
K := 5
var jobQueueWg sync.WaitGroup
queue := util.NewQueue()
jobQueueWg.Add(1)
queue.Enqueue(parentPath)
var isTerminating bool
for i := 0; i < K; i++ {
go func() {
for {
if isTerminating {
break
}
t := queue.Dequeue()
if t == nil {
time.Sleep(329 * time.Millisecond)
continue
}
dir := t.(filer2.FullPath)
processErr := processOneDirectory(writer, filerClient, dir, queue, &jobQueueWg, fn)
if processErr != nil {
err = processErr
}
jobQueueWg.Done()
}
}()
}
jobQueueWg.Wait()
isTerminating = true
return
}
func processOneDirectory(writer io.Writer, filerClient filer2.FilerClient, parentPath filer2.FullPath, queue *util.Queue, jobQueueWg *sync.WaitGroup, fn func(parentPath filer2.FullPath, entry *filer_pb.Entry)) (err error) {
return filer2.ReadDirAllEntries(filerClient, parentPath, "", func(entry *filer_pb.Entry, isLast bool) {
fn(parentPath, entry)
if entry.IsDirectory {
subDir := fmt.Sprintf("%s/%s", parentPath, entry.Name)
if parentPath == "/" {
subDir = "/" + entry.Name
}
jobQueueWg.Add(1)
queue.Enqueue(filer2.FullPath(subDir))
}
})
}