diff --git a/changelog/unreleased/pull-2978 b/changelog/unreleased/pull-2978
new file mode 100644
index 000000000..78b0a5e10
--- /dev/null
+++ b/changelog/unreleased/pull-2978
@@ -0,0 +1,8 @@
+Enhancement: Warn if parent snapshot cannot be loaded during backup
+
+During a backup restic uses the parent snapshot to check whether a file was
+changed and has to be backed up again. For this check the backup has to read
+the directories contained in the old snapshot. If a tree blob cannot be
+loaded, restic now warns about this problem with the backup repository.
+
+https://github.com/restic/restic/pull/2978
diff --git a/cmd/restic/integration_test.go b/cmd/restic/integration_test.go
index 71e03ae5f..9c01939ec 100644
--- a/cmd/restic/integration_test.go
+++ b/cmd/restic/integration_test.go
@@ -368,7 +368,7 @@ func TestBackupNonExistingFile(t *testing.T) {
testRunBackup(t, "", dirs, opts, env.gopts)
}
-func removeDataPacksExcept(gopts GlobalOptions, t *testing.T, keep restic.IDSet) {
+func removePacksExcept(gopts GlobalOptions, t *testing.T, keep restic.IDSet, removeTreePacks bool) {
r, err := OpenRepository(gopts)
rtest.OK(t, err)
@@ -383,7 +383,7 @@ func removeDataPacksExcept(gopts GlobalOptions, t *testing.T, keep restic.IDSet)
// remove all packs containing data blobs
rtest.OK(t, r.List(gopts.ctx, restic.PackFile, func(id restic.ID, size int64) error {
- if treePacks.Has(id) || keep.Has(id) {
+ if treePacks.Has(id) != removeTreePacks || keep.Has(id) {
return nil
}
return r.Backend().Remove(gopts.ctx, restic.Handle{Type: restic.PackFile, Name: id.String()})
@@ -406,7 +406,7 @@ func TestBackupSelfHealing(t *testing.T) {
testRunCheck(t, env.gopts)
// remove all data packs
- removeDataPacksExcept(env.gopts, t, restic.NewIDSet())
+ removePacksExcept(env.gopts, t, restic.NewIDSet(), false)
testRunRebuildIndex(t, env.gopts)
// now the repo is also missing the data blob in the index; check should report this
@@ -420,6 +420,56 @@ func TestBackupSelfHealing(t *testing.T) {
testRunCheck(t, env.gopts)
}
+func TestBackupTreeLoadError(t *testing.T) {
+ env, cleanup := withTestEnvironment(t)
+ defer cleanup()
+
+ testRunInit(t, env.gopts)
+ p := filepath.Join(env.testdata, "test/test")
+ rtest.OK(t, os.MkdirAll(filepath.Dir(p), 0755))
+ rtest.OK(t, appendRandomData(p, 5))
+
+ opts := BackupOptions{}
+ // Backup a subdirectory first, such that we can remove the tree pack for the subdirectory
+ testRunBackup(t, env.testdata, []string{"test"}, opts, env.gopts)
+
+ r, err := OpenRepository(env.gopts)
+ rtest.OK(t, err)
+ rtest.OK(t, r.LoadIndex(env.gopts.ctx))
+ // collect tree packs of subdirectory
+ subTreePacks := restic.NewIDSet()
+ for _, idx := range r.Index().(*repository.MasterIndex).All() {
+ for _, id := range idx.TreePacks() {
+ subTreePacks.Insert(id)
+ }
+ }
+
+ testRunBackup(t, filepath.Dir(env.testdata), []string{filepath.Base(env.testdata)}, opts, env.gopts)
+ testRunCheck(t, env.gopts)
+
+ // delete the subdirectory pack first
+ for id := range subTreePacks {
+ rtest.OK(t, r.Backend().Remove(env.gopts.ctx, restic.Handle{Type: restic.PackFile, Name: id.String()}))
+ }
+ testRunRebuildIndex(t, env.gopts)
+ // now the repo is missing the tree blob in the index; check should report this
+ rtest.Assert(t, runCheck(CheckOptions{}, env.gopts, nil) != nil, "check should have reported an error")
+ // second backup should report an error but "heal" this situation
+ err = testRunBackupAssumeFailure(t, filepath.Dir(env.testdata), []string{filepath.Base(env.testdata)}, opts, env.gopts)
+ rtest.Assert(t, err != nil, "backup should have reported an error for the subdirectory")
+ testRunCheck(t, env.gopts)
+
+ // remove all tree packs
+ removePacksExcept(env.gopts, t, restic.NewIDSet(), true)
+ testRunRebuildIndex(t, env.gopts)
+ // now the repo is also missing the data blob in the index; check should report this
+ rtest.Assert(t, runCheck(CheckOptions{}, env.gopts, nil) != nil, "check should have reported an error")
+ // second backup should report an error but "heal" this situation
+ err = testRunBackupAssumeFailure(t, filepath.Dir(env.testdata), []string{filepath.Base(env.testdata)}, opts, env.gopts)
+ rtest.Assert(t, err != nil, "backup should have reported an error")
+ testRunCheck(t, env.gopts)
+}
+
func includes(haystack []string, needle string) bool {
for _, s := range haystack {
if s == needle {
@@ -1396,7 +1446,7 @@ func TestPruneWithDamagedRepository(t *testing.T) {
testRunBackup(t, "", []string{filepath.Join(env.testdata, "0", "0", "9", "3")}, opts, env.gopts)
snapshotIDs := testRunList(t, "snapshots", env.gopts)
- removeDataPacksExcept(env.gopts, t, oldPacks)
+ removePacksExcept(env.gopts, t, oldPacks, false)
rtest.Assert(t, len(snapshotIDs) == 1,
"expected one snapshot, got %v", snapshotIDs)
diff --git a/internal/archiver/archiver.go b/internal/archiver/archiver.go
index d6dd6660a..42fc03310 100644
--- a/internal/archiver/archiver.go
+++ b/internal/archiver/archiver.go
@@ -191,19 +191,29 @@ func (arch *Archiver) nodeFromFileInfo(filename string, fi os.FileInfo) (*restic
}
// loadSubtree tries to load the subtree referenced by node. In case of an error, nil is returned.
-func (arch *Archiver) loadSubtree(ctx context.Context, node *restic.Node) *restic.Tree {
+// If there is no node to load, then nil is returned without an error.
+func (arch *Archiver) loadSubtree(ctx context.Context, node *restic.Node) (*restic.Tree, error) {
if node == nil || node.Type != "dir" || node.Subtree == nil {
- return nil
+ return nil, nil
}
tree, err := arch.Repo.LoadTree(ctx, *node.Subtree)
if err != nil {
debug.Log("unable to load tree %v: %v", node.Subtree.Str(), err)
- // TODO: handle error
- return nil
+ // a tree in the repository is not readable -> warn the user
+ return nil, arch.wrapLoadTreeError(*node.Subtree, err)
}
- return tree
+ return tree, nil
+}
+
+func (arch *Archiver) wrapLoadTreeError(id restic.ID, err error) error {
+ if arch.Repo.Index().Has(id, restic.TreeBlob) {
+ err = errors.Errorf("tree %v could not be loaded; the repository could be damaged: %v", id, err)
+ } else {
+ err = errors.Errorf("tree %v is not known; the repository could be damaged, run `rebuild-index` to try to repair it", id)
+ }
+ return err
}
// SaveDir stores a directory in the repo and returns the node. snPath is the
@@ -434,7 +444,10 @@ func (arch *Archiver) Save(ctx context.Context, snPath, target string, previous
snItem := snPath + "/"
start := time.Now()
- oldSubtree := arch.loadSubtree(ctx, previous)
+ oldSubtree, err := arch.loadSubtree(ctx, previous)
+ if err != nil {
+ arch.error(abstarget, fi, err)
+ }
fn.isTree = true
fn.tree, err = arch.SaveDir(ctx, snPath, fi, target, oldSubtree,
@@ -572,7 +585,10 @@ func (arch *Archiver) SaveTree(ctx context.Context, snPath string, atree *Tree,
start := time.Now()
oldNode := previous.Find(name)
- oldSubtree := arch.loadSubtree(ctx, oldNode)
+ oldSubtree, err := arch.loadSubtree(ctx, oldNode)
+ if err != nil {
+ arch.error(join(snPath, name), nil, err)
+ }
// not a leaf node, archive subtree
subtree, err := arch.SaveTree(ctx, join(snPath, name), &subatree, oldSubtree)
@@ -730,6 +746,7 @@ func (arch *Archiver) loadParentTree(ctx context.Context, snapshotID restic.ID)
tree, err := arch.Repo.LoadTree(ctx, *sn.Tree)
if err != nil {
debug.Log("unable to load tree %v: %v", *sn.Tree, err)
+ arch.error("/", nil, arch.wrapLoadTreeError(*sn.Tree, err))
return nil
}
return tree