From d35023c7139e7c488644a03c646df3415b9a1a4b Mon Sep 17 00:00:00 2001
From: Chris Lu <chris.lu@gmail.com>
Date: Tue, 16 Apr 2019 01:06:32 -0700
Subject: [PATCH] weed shell: add command fs.meta.save

---
 weed/shell/command_fs_meta_save.go | 142 +++++++++++++++++++++++++++++
 1 file changed, 142 insertions(+)
 create mode 100644 weed/shell/command_fs_meta_save.go

diff --git a/weed/shell/command_fs_meta_save.go b/weed/shell/command_fs_meta_save.go
new file mode 100644
index 000000000..b874db31b
--- /dev/null
+++ b/weed/shell/command_fs_meta_save.go
@@ -0,0 +1,142 @@
+package shell
+
+import (
+	"context"
+	"fmt"
+	"io"
+	"os"
+
+	"github.com/chrislusf/seaweedfs/weed/filer2"
+	"github.com/chrislusf/seaweedfs/weed/pb/filer_pb"
+	"github.com/chrislusf/seaweedfs/weed/util"
+	"github.com/golang/protobuf/proto"
+)
+
+func init() {
+	commands = append(commands, &commandFsMetaSave{})
+}
+
+type commandFsMetaSave struct {
+}
+
+func (c *commandFsMetaSave) Name() string {
+	return "fs.meta.save"
+}
+
+func (c *commandFsMetaSave) Help() string {
+	return `recursively save directory and file meta data to a local file
+
+	fs.meta.save	# save current meta data from current directory
+
+	The meta data will be saved into a local <filer_host>_<port>.meta file.
+	These meta data can be later loaded by fs.meta.load command.
+
+`
+}
+
+func (c *commandFsMetaSave) Do(args []string, commandEnv *commandEnv, writer io.Writer) (err error) {
+
+	filerServer, filerPort, path, err := commandEnv.parseUrl(findInputDirectory(args))
+	if err != nil {
+		return err
+	}
+
+	ctx := context.Background()
+
+	return commandEnv.withFilerClient(ctx, filerServer, filerPort, func(client filer_pb.SeaweedFilerClient) error {
+
+		fileName := fmt.Sprintf("%s-%d.meta", filerServer, filerPort)
+
+		dst, err := os.OpenFile(fileName, os.O_WRONLY|os.O_CREATE|os.O_TRUNC, 0644)
+		if err != nil {
+			return nil
+		}
+		defer dst.Close()
+
+		var dirCount, fileCount uint64
+
+		sizeBuf := make([]byte, 4)
+
+		err = doTraverse(ctx, writer, client, filer2.FullPath(path), func(parentPath filer2.FullPath, entry *filer_pb.Entry) error {
+
+			protoMessage := &filer_pb.FullEntry{
+				Dir:   string(parentPath),
+				Entry: entry,
+			}
+
+			bytes, err := proto.Marshal(protoMessage)
+			if err != nil {
+				return fmt.Errorf("marshall error: %v", err)
+			}
+
+			util.Uint32toBytes(sizeBuf, uint32(len(bytes)))
+
+			dst.Write(sizeBuf)
+			dst.Write(bytes)
+
+			if entry.IsDirectory {
+				dirCount++
+			} else {
+				fileCount++
+			}
+
+			println(parentPath.Child(entry.Name))
+
+			return nil
+
+		})
+
+		if err == nil {
+			fmt.Fprintf(writer, "\ntotal %d directories, %d files", dirCount, fileCount)
+			fmt.Fprintf(writer, "\nmeta data for http://%s:%d%s is saved to %s\n", filerServer, filerPort, path, fileName)
+		}
+
+		return err
+
+	})
+
+}
+func doTraverse(ctx context.Context, writer io.Writer, client filer_pb.SeaweedFilerClient, parentPath filer2.FullPath, fn func(parentPath filer2.FullPath, entry *filer_pb.Entry) error) (err error) {
+
+	paginatedCount := -1
+	startFromFileName := ""
+	paginateSize := 1000
+
+	for paginatedCount == -1 || paginatedCount == paginateSize {
+		resp, listErr := client.ListEntries(ctx, &filer_pb.ListEntriesRequest{
+			Directory:          string(parentPath),
+			Prefix:             "",
+			StartFromFileName:  startFromFileName,
+			InclusiveStartFrom: false,
+			Limit:              uint32(paginateSize),
+		})
+		if listErr != nil {
+			err = listErr
+			return
+		}
+
+		paginatedCount = len(resp.Entries)
+
+		for _, entry := range resp.Entries {
+
+			if err = fn(parentPath, entry); err != nil {
+				return err
+			}
+
+			if entry.IsDirectory {
+				subDir := fmt.Sprintf("%s/%s", parentPath, entry.Name)
+				if parentPath == "/" {
+					subDir = "/" + entry.Name
+				}
+				if err = doTraverse(ctx, writer, client, filer2.FullPath(subDir), fn); err != nil {
+					return err
+				}
+			}
+			startFromFileName = entry.Name
+
+		}
+	}
+
+	return
+
+}