package restic import ( "fmt" "os" "path/filepath" "syscall" "github.com/restic/restic/backend" "github.com/restic/restic/server" "github.com/juju/errors" ) // Restorer is used to restore a snapshot to a directory. type Restorer struct { s *server.Server sn *Snapshot Error func(dir string, node *Node, err error) error Filter func(item string, dstpath string, node *Node) bool } var restorerAbortOnAllErrors = func(str string, node *Node, err error) error { return err } // NewRestorer creates a restorer preloaded with the content from the snapshot id. func NewRestorer(s *server.Server, id backend.ID) (*Restorer, error) { r := &Restorer{s: s, Error: restorerAbortOnAllErrors} var err error r.sn, err = LoadSnapshot(s, id) if err != nil { return nil, errors.Annotate(err, "load snapshot for restorer") } return r, nil } func (res *Restorer) restoreTo(dst string, dir string, treeID backend.ID) error { tree, err := LoadTree(res.s, treeID) if err != nil { return res.Error(dir, nil, errors.Annotate(err, "LoadTree")) } for _, node := range tree.Nodes { if err := res.restoreNodeTo(node, dir, dst); err != nil { return err } if node.Type == "dir" { if node.Subtree == nil { return fmt.Errorf("Dir without subtree in tree %v", treeID.Str()) } subp := filepath.Join(dir, node.Name) err = res.restoreTo(dst, subp, node.Subtree) if err != nil { err = res.Error(subp, node, errors.Annotate(err, "restore subtree")) if err != nil { return err } } } } return nil } func (res *Restorer) restoreNodeTo(node *Node, dir string, dst string) error { dstPath := filepath.Join(dst, dir, node.Name) if res.Filter != nil && res.Filter(filepath.Join(dir, node.Name), dstPath, node) { return nil } err := node.CreateAt(dstPath, res.s) // Did it fail because of ENOENT? if pe, ok := errors.Cause(err).(*os.PathError); ok { errn, ok := pe.Err.(syscall.Errno) if ok && errn == syscall.ENOENT { // Create parent directories and retry err = os.MkdirAll(filepath.Dir(dstPath), 0700) if err == nil || err == os.ErrExist { err = node.CreateAt(dstPath, res.s) } } } if err != nil { err = res.Error(dstPath, node, errors.Annotate(err, "create node")) if err != nil { return err } } return nil } // RestoreTo creates the directories and files in the snapshot below dir. // Before an item is created, res.Filter is called. func (res *Restorer) RestoreTo(dir string) error { return res.restoreTo(dir, "", res.sn.Tree) } // Snapshot returns the snapshot this restorer is configured to use. func (res *Restorer) Snapshot() *Snapshot { return res.sn }