package restorer import ( "context" "os" "path/filepath" "github.com/restic/restic/internal/errors" "github.com/restic/restic/internal/debug" "github.com/restic/restic/internal/fs" "github.com/restic/restic/internal/restic" ) // Restorer is used to restore a snapshot to a directory. type Restorer struct { repo restic.Repository sn *restic.Snapshot Error func(dir string, node *restic.Node, err error) error SelectFilter func(item string, dstpath string, node *restic.Node) (selectedForRestore bool, childMayBeSelected bool) } var restorerAbortOnAllErrors = func(str string, node *restic.Node, err error) error { return err } // NewRestorer creates a restorer preloaded with the content from the snapshot id. func NewRestorer(repo restic.Repository, id restic.ID) (*Restorer, error) { r := &Restorer{ repo: repo, Error: restorerAbortOnAllErrors, SelectFilter: func(string, string, *restic.Node) (bool, bool) { return true, true }, } var err error r.sn, err = restic.LoadSnapshot(context.TODO(), repo, id) if err != nil { return nil, err } return r, nil } // restoreTo restores a tree from the repo to a destination. target is the path in // the file system, location within the snapshot. func (res *Restorer) restoreTo(ctx context.Context, target, location string, treeID restic.ID, idx *restic.HardlinkIndex) error { debug.Log("%v %v %v", target, location, treeID) tree, err := res.repo.LoadTree(ctx, treeID) if err != nil { debug.Log("error loading tree %v: %v", treeID, err) return res.Error(location, nil, err) } for _, node := range tree.Nodes { // ensure that the node name does not contain anything that refers to a // top-level directory. nodeName := filepath.Base(filepath.Join(string(filepath.Separator), node.Name)) if nodeName != node.Name { debug.Log("node %q has invalid name %q", node.Name, nodeName) err := res.Error(location, node, errors.New("node has invalid name")) if err != nil { return err } continue } nodeTarget := filepath.Join(target, nodeName) nodeLocation := filepath.Join(location, nodeName) if target == nodeTarget || !fs.HasPathPrefix(target, nodeTarget) { debug.Log("target: %v %v", target, nodeTarget) debug.Log("node %q has invalid target path %q", node.Name, nodeTarget) err := res.Error(nodeLocation, node, errors.New("node has invalid path")) if err != nil { return err } continue } // sockets cannot be restored if node.Type == "socket" { continue } selectedForRestore, childMayBeSelected := res.SelectFilter(nodeLocation, nodeTarget, node) debug.Log("SelectFilter returned %v %v", selectedForRestore, childMayBeSelected) if node.Type == "dir" && childMayBeSelected { if node.Subtree == nil { return errors.Errorf("Dir without subtree in tree %v", treeID.Str()) } err = res.restoreTo(ctx, nodeTarget, nodeLocation, *node.Subtree, idx) if err != nil { err = res.Error(nodeLocation, node, err) if err != nil { return err } } } if selectedForRestore { err = res.restoreNodeTo(ctx, node, nodeTarget, nodeLocation, idx) if err != nil { err = res.Error(nodeLocation, node, errors.Wrap(err, "restoreNodeTo")) if err != nil { return err } } // Restore directory timestamp at the end. If we would do it earlier, restoring files within // the directory would overwrite the timestamp of the directory they are in. err = node.RestoreTimestamps(nodeTarget) if err != nil { err = res.Error(nodeLocation, node, errors.Wrap(err, "RestoreTimestamps")) if err != nil { return err } } } } return nil } func (res *Restorer) restoreNodeTo(ctx context.Context, node *restic.Node, target, location string, idx *restic.HardlinkIndex) error { debug.Log("%v %v %v", node.Name, target, location) err := node.CreateAt(ctx, target, res.repo, idx) if err != nil { debug.Log("node.CreateAt(%s) error %v", target, err) } // Did it fail because of ENOENT? if err != nil && os.IsNotExist(errors.Cause(err)) { debug.Log("create intermediate paths") // Create parent directories and retry err = fs.MkdirAll(filepath.Dir(target), 0700) if err == nil || os.IsExist(errors.Cause(err)) { err = node.CreateAt(ctx, target, res.repo, idx) } } if err != nil { debug.Log("error %v", err) err = res.Error(location, node, err) if err != nil { return err } } return nil } // RestoreTo creates the directories and files in the snapshot below dst. // Before an item is created, res.Filter is called. func (res *Restorer) RestoreTo(ctx context.Context, dst string) error { var err error if !filepath.IsAbs(dst) { dst, err = filepath.Abs(dst) if err != nil { return errors.Wrap(err, "Abs") } } idx := restic.NewHardlinkIndex() return res.restoreTo(ctx, dst, string(filepath.Separator), *res.sn.Tree, idx) } // Snapshot returns the snapshot this restorer is configured to use. func (res *Restorer) Snapshot() *restic.Snapshot { return res.sn }