restic/internal/restorer.go
Alexander Neumann 6caeff2408 Run goimports
2017-07-23 14:21:03 +02:00

130 lines
3.4 KiB
Go

package restic
import (
"context"
"os"
"path/filepath"
"github.com/restic/restic/internal/errors"
"github.com/restic/restic/internal/debug"
"github.com/restic/restic/internal/fs"
)
// Restorer is used to restore a snapshot to a directory.
type Restorer struct {
repo Repository
sn *Snapshot
Error func(dir string, node *Node, err error) error
SelectFilter 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(repo Repository, id ID) (*Restorer, error) {
r := &Restorer{
repo: repo, Error: restorerAbortOnAllErrors,
SelectFilter: func(string, string, *Node) bool { return true },
}
var err error
r.sn, err = LoadSnapshot(context.TODO(), repo, id)
if err != nil {
return nil, err
}
return r, nil
}
func (res *Restorer) restoreTo(ctx context.Context, dst string, dir string, treeID ID, idx *HardlinkIndex) error {
tree, err := res.repo.LoadTree(ctx, treeID)
if err != nil {
return res.Error(dir, nil, err)
}
for _, node := range tree.Nodes {
selectedForRestore := res.SelectFilter(filepath.Join(dir, node.Name),
filepath.Join(dst, dir, node.Name), node)
debug.Log("SelectForRestore returned %v", selectedForRestore)
if selectedForRestore {
err := res.restoreNodeTo(ctx, node, dir, dst, idx)
if err != nil {
return err
}
}
if node.Type == "dir" {
if node.Subtree == nil {
return errors.Errorf("Dir without subtree in tree %v", treeID.Str())
}
subp := filepath.Join(dir, node.Name)
err = res.restoreTo(ctx, dst, subp, *node.Subtree, idx)
if err != nil {
err = res.Error(subp, node, err)
if err != nil {
return err
}
}
if selectedForRestore {
// 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.
if err := node.RestoreTimestamps(filepath.Join(dst, dir, node.Name)); err != nil {
return err
}
}
}
}
return nil
}
func (res *Restorer) restoreNodeTo(ctx context.Context, node *Node, dir string, dst string, idx *HardlinkIndex) error {
debug.Log("node %v, dir %v, dst %v", node.Name, dir, dst)
dstPath := filepath.Join(dst, dir, node.Name)
err := node.CreateAt(ctx, dstPath, res.repo, idx)
if err != nil {
debug.Log("node.CreateAt(%s) error %v", dstPath, 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(dstPath), 0700)
if err == nil || os.IsExist(errors.Cause(err)) {
err = node.CreateAt(ctx, dstPath, res.repo, idx)
}
}
if err != nil {
debug.Log("error %v", err)
err = res.Error(dstPath, node, err)
if err != nil {
return err
}
}
debug.Log("successfully restored %v", node.Name)
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 {
idx := 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() *Snapshot {
return res.sn
}