Move restore functionality into khepri package

This commit is contained in:
Alexander Neumann 2014-08-11 23:14:40 +02:00
parent 2428843faa
commit d66996e648
3 changed files with 162 additions and 144 deletions

View File

@ -2,146 +2,11 @@ package main
import (
"errors"
"fmt"
"io"
"log"
"os"
"path/filepath"
"syscall"
"github.com/fd0/khepri"
)
func restore_file(repo *khepri.Repository, node *khepri.Node, path string) (err error) {
switch node.Type {
case "file":
// TODO: handle hard links
rd, err := repo.Get(khepri.TYPE_BLOB, node.Content)
if err != nil {
return err
}
f, err := os.OpenFile(path, os.O_CREATE|os.O_WRONLY, 0600)
defer f.Close()
if err != nil {
return err
}
_, err = io.Copy(f, rd)
if err != nil {
return err
}
case "symlink":
err = os.Symlink(node.LinkTarget, path)
if err != nil {
return err
}
err = os.Lchown(path, int(node.UID), int(node.GID))
if err != nil {
return err
}
f, err := os.OpenFile(path, khepri.O_PATH|syscall.O_NOFOLLOW, 0600)
defer f.Close()
if err != nil {
return err
}
var utimes = []syscall.Timeval{
syscall.NsecToTimeval(node.AccessTime.UnixNano()),
syscall.NsecToTimeval(node.ModTime.UnixNano()),
}
err = syscall.Futimes(int(f.Fd()), utimes)
if err != nil {
return err
}
return nil
case "dev":
err = syscall.Mknod(path, syscall.S_IFBLK|0600, int(node.Device))
if err != nil {
return err
}
case "chardev":
err = syscall.Mknod(path, syscall.S_IFCHR|0600, int(node.Device))
if err != nil {
return err
}
case "fifo":
err = syscall.Mkfifo(path, 0600)
if err != nil {
return err
}
case "socket":
// nothing to do, we do not restore sockets
default:
return fmt.Errorf("filetype %q not implemented!\n", node.Type)
}
err = os.Chmod(path, node.Mode)
if err != nil {
return err
}
err = os.Chown(path, int(node.UID), int(node.GID))
if err != nil {
return err
}
err = os.Chtimes(path, node.AccessTime, node.ModTime)
if err != nil {
return err
}
return nil
}
func restore_subtree(repo *khepri.Repository, tree *khepri.Tree, path string) {
fmt.Printf("restore_subtree(%s)\n", path)
for _, node := range tree.Nodes {
nodepath := filepath.Join(path, node.Name)
// fmt.Printf("%s:%s\n", node.Type, nodepath)
if node.Type == "dir" {
err := os.Mkdir(nodepath, 0700)
if err != nil {
fmt.Fprintf(os.Stderr, "%s\n", err)
continue
}
err = os.Chmod(nodepath, node.Mode)
if err != nil {
fmt.Fprintf(os.Stderr, "%s\n", err)
continue
}
err = os.Chown(nodepath, int(node.UID), int(node.GID))
if err != nil {
fmt.Fprintf(os.Stderr, "%s\n", err)
continue
}
restore_subtree(repo, node.Tree, filepath.Join(path, node.Name))
err = os.Chtimes(nodepath, node.AccessTime, node.ModTime)
if err != nil {
fmt.Fprintf(os.Stderr, "%s\n", err)
continue
}
} else {
err := restore_file(repo, node, nodepath)
if err != nil {
fmt.Fprintf(os.Stderr, "%s\n", err)
continue
}
}
}
}
func commandRestore(repo *khepri.Repository, args []string) error {
if len(args) != 2 {
return errors.New("usage: restore ID dir")
@ -154,23 +19,16 @@ func commandRestore(repo *khepri.Repository, args []string) error {
target := args[1]
err = os.MkdirAll(target, 0700)
if err != nil {
return err
}
sn, err := khepri.LoadSnapshot(repo, id)
if err != nil {
log.Fatalf("error loading snapshot %s", id)
}
tree, err := khepri.NewTreeFromRepo(repo, sn.Content)
err = sn.RestoreAt(target)
if err != nil {
log.Fatalf("error loading tree %s", sn.Content)
log.Fatalf("error restoring snapshot %s", id)
}
restore_subtree(repo, tree, target)
log.Printf("%q restored to %q\n", id, target)
return nil

View File

@ -18,6 +18,7 @@ type Snapshot struct {
UID string `json:"uid,omitempty"`
GID string `json:"gid,omitempty"`
id ID `json:omit`
repo *Repository
}
func NewSnapshot(dir string) *Snapshot {
@ -84,10 +85,27 @@ func LoadSnapshot(repo *Repository, id ID) (*Snapshot, error) {
}
sn.id = id
sn.repo = repo
return sn, nil
}
func (sn *Snapshot) RestoreAt(path string) error {
err := os.MkdirAll(path, 0700)
if err != nil {
return err
}
if sn.Tree == nil {
sn.Tree, err = NewTreeFromRepo(sn.repo, sn.Content)
if err != nil {
return err
}
}
return sn.Tree.CreateAt(path)
}
func (sn *Snapshot) ID() ID {
return sn.id
}

142
tree.go
View File

@ -35,6 +35,7 @@ type Node struct {
Content ID `json:"content,omitempty"`
Subtree ID `json:"subtree,omitempty"`
Tree *Tree `json:"-"`
repo *Repository
}
func NewTree() *Tree {
@ -65,6 +66,7 @@ func NewTreeFromPath(repo *Repository, dir string) (*Tree, error) {
if err != nil {
return nil, err
}
node.repo = repo
tree.Nodes = append(tree.Nodes, node)
@ -152,6 +154,8 @@ func NewTreeFromRepo(repo *Repository, id ID) (*Tree, error) {
}
for _, node := range tree.Nodes {
node.repo = repo
if node.Subtree != nil {
node.Tree, err = NewTreeFromRepo(repo, node.Subtree)
if err != nil {
@ -163,6 +167,53 @@ func NewTreeFromRepo(repo *Repository, id ID) (*Tree, error) {
return tree, nil
}
func (tree *Tree) CreateAt(path string) error {
for _, node := range tree.Nodes {
nodepath := filepath.Join(path, node.Name)
// fmt.Printf("%s:%s\n", node.Type, nodepath)
if node.Type == "dir" {
err := os.Mkdir(nodepath, 0700)
if err != nil {
fmt.Fprintf(os.Stderr, "%s\n", err)
continue
}
err = os.Chmod(nodepath, node.Mode)
if err != nil {
fmt.Fprintf(os.Stderr, "%s\n", err)
continue
}
err = os.Chown(nodepath, int(node.UID), int(node.GID))
if err != nil {
fmt.Fprintf(os.Stderr, "%s\n", err)
continue
}
err = node.Tree.CreateAt(filepath.Join(path, node.Name))
if err != nil {
return err
}
err = os.Chtimes(nodepath, node.AccessTime, node.ModTime)
if err != nil {
fmt.Fprintf(os.Stderr, "%s\n", err)
continue
}
} else {
err := node.CreateAt(nodepath)
if err != nil {
fmt.Fprintf(os.Stderr, "%s\n", err)
continue
}
}
}
return nil
}
// TODO: make sure that node.Type is valid
func (node *Node) fill_extra(path string, fi os.FileInfo) (err error) {
@ -237,3 +288,94 @@ func NodeFromFileInfo(path string, fi os.FileInfo) (*Node, error) {
err := node.fill_extra(path, fi)
return node, err
}
func (node *Node) CreateAt(path string) error {
if node.repo == nil {
return fmt.Errorf("repository is nil!")
}
switch node.Type {
case "file":
// TODO: handle hard links
rd, err := node.repo.Get(TYPE_BLOB, node.Content)
if err != nil {
return err
}
f, err := os.OpenFile(path, os.O_CREATE|os.O_WRONLY, 0600)
defer f.Close()
if err != nil {
return err
}
_, err = io.Copy(f, rd)
if err != nil {
return err
}
f.Close()
case "symlink":
err := os.Symlink(node.LinkTarget, path)
if err != nil {
return err
}
err = os.Lchown(path, int(node.UID), int(node.GID))
if err != nil {
return err
}
f, err := os.OpenFile(path, O_PATH|syscall.O_NOFOLLOW, 0600)
defer f.Close()
if err != nil {
return err
}
var utimes = []syscall.Timeval{
syscall.NsecToTimeval(node.AccessTime.UnixNano()),
syscall.NsecToTimeval(node.ModTime.UnixNano()),
}
err = syscall.Futimes(int(f.Fd()), utimes)
if err != nil {
return err
}
return nil
case "dev":
err := syscall.Mknod(path, syscall.S_IFBLK|0600, int(node.Device))
if err != nil {
return err
}
case "chardev":
err := syscall.Mknod(path, syscall.S_IFCHR|0600, int(node.Device))
if err != nil {
return err
}
case "fifo":
err := syscall.Mkfifo(path, 0600)
if err != nil {
return err
}
case "socket":
// nothing to do, we do not restore sockets
default:
return fmt.Errorf("filetype %q not implemented!\n", node.Type)
}
err := os.Chmod(path, node.Mode)
if err != nil {
return err
}
err = os.Chown(path, int(node.UID), int(node.GID))
if err != nil {
return err
}
err = os.Chtimes(path, node.AccessTime, node.ModTime)
if err != nil {
return err
}
return nil
}