Rework index decode and handling old format

checker/checker.go

@@ -3,6 +3,7 @@ package checker
 import (
 	"errors"
 	"fmt"
+	"os"
 	"sync"
 
 	"github.com/restic/restic"
@@ -58,15 +59,26 @@ func (c *Checker) LoadIndex() error {
 
 	indexCh := make(chan indexRes)
 
-	worker := func(id string, done <-chan struct{}) error {
+	worker := func(id backend.ID, done <-chan struct{}) error {
 		debug.Log("LoadIndex", "worker got index %v", id)
-		idx, err := repository.LoadIndex(c.repo, id)
+		idx, err := repository.LoadIndexWithDecoder(c.repo, id.String(), repository.DecodeIndex)
+		if err == repository.ErrOldIndexFormat {
+			debug.Log("LoadIndex", "old index format found, converting")
+			fmt.Fprintf(os.Stderr, "convert index %v to new format\n", id.Str())
+			id, err = repository.ConvertIndex(c.repo, id)
+			if err != nil {
+				return err
+			}
+
+			idx, err = repository.LoadIndexWithDecoder(c.repo, id.String(), repository.DecodeIndex)
+		}
+
 		if err != nil {
 			return err
 		}
 
 		select {
-		case indexCh <- indexRes{Index: idx, ID: id}:
+		case indexCh <- indexRes{Index: idx, ID: id.String()}:
 		case <-done:
 		}
 
@@ -77,7 +89,8 @@ func (c *Checker) LoadIndex() error {
 	go func() {
 		defer close(indexCh)
 		debug.Log("LoadIndex", "start loading indexes in parallel")
-		perr = repository.FilesInParallel(c.repo.Backend(), backend.Index, defaultParallelism, worker)
+		perr = repository.FilesInParallel(c.repo.Backend(), backend.Index, defaultParallelism,
+			repository.ParallelWorkFuncParseID(worker))
 		debug.Log("LoadIndex", "loading indexes finished, error: %v", perr)
 	}()
 

checker/checker_test.go

@@ -91,8 +91,8 @@ func TestUnreferencedPack(t *testing.T) {
 	WithTestEnvironment(t, checkerTestData, func(repodir string) {
 		repo := OpenLocalRepo(t, repodir)
 
-		// index 8eb5 only references pack 60e0
-		indexID := "8eb5b61062bf8e959f244fba0c971108bc8d4d2a4b236f71a704998e28cc5cf6"
+		// index 3f1a only references pack 60e0
+		indexID := "3f1abfcb79c6f7d0a3be517d2c83c8562fba64ef2c8e9a3544b4edaf8b5e3b44"
 		packID := "60e0438dcb978ec6860cc1f8c43da648170ee9129af8f650f876bad19f8f788e"
 		OK(t, repo.Backend().Remove(backend.Index, indexID))
 

repository/index.go

@@ -17,6 +17,8 @@ import (
 type Index struct {
 	m    sync.Mutex
 	pack map[backend.ID]indexEntry
+
+	supersedes backend.IDs
 }
 
 type indexEntry struct {
@@ -139,6 +141,11 @@ func (idx *Index) Merge(other *Index) {
 	debug.Log("Index.Merge", "done merging index")
 }
 
+// Supersedes returns the list of indexes this index supersedes, if any.
+func (idx *Index) Supersedes() backend.IDs {
+	return idx.supersedes
+}
+
 // PackedBlob is a blob already saved within a pack.
 type PackedBlob struct {
 	pack.Blob
@@ -257,22 +264,20 @@ func (idx *Index) generatePackList(selectFn func(indexEntry) bool) ([]*packJSON,
 }
 
 type jsonIndex struct {
-	Supersedes []backend.ID `json:"supersedes,omitempty"`
-	Packs      []*packJSON  `json:"packs"`
+	Supersedes backend.IDs `json:"supersedes,omitempty"`
+	Packs      []*packJSON `json:"packs"`
 }
 
 type jsonOldIndex []*packJSON
 
 // encode writes the JSON serialization of the index filtered by selectFn to enc.
-func (idx *Index) encode(w io.Writer, supersedes []backend.ID, selectFn func(indexEntry) bool) error {
-	list, err := idx.generatePackList(func(entry indexEntry) bool {
-		return !entry.old
-	})
+func (idx *Index) encode(w io.Writer, supersedes backend.IDs, selectFn func(indexEntry) bool) error {
+	list, err := idx.generatePackList(selectFn)
 	if err != nil {
 		return err
 	}
 
-	debug.Log("Index.Encode", "done")
+	debug.Log("Index.Encode", "done, %d entries selected", len(list))
 
 	enc := json.NewEncoder(w)
 	idxJSON := jsonIndex{
@@ -290,7 +295,7 @@ func (idx *Index) Encode(w io.Writer) error {
 	idx.m.Lock()
 	defer idx.m.Unlock()
 
-	return idx.encode(w, nil, func(e indexEntry) bool { return !e.old })
+	return idx.encode(w, idx.supersedes, func(e indexEntry) bool { return !e.old })
 }
 
 // Dump writes the pretty-printed JSON representation of the index to w.
@@ -333,47 +338,48 @@ func isErrOldIndex(err error) bool {
 var ErrOldIndexFormat = errors.New("index has old format")
 
 // DecodeIndex loads and unserializes an index from rd.
-func DecodeIndex(rd io.Reader) (*Index, backend.IDs, error) {
+func DecodeIndex(rd io.Reader) (idx *Index, err error) {
 	debug.Log("Index.DecodeIndex", "Start decoding index")
 	idxJSON := jsonIndex{}
 
 	dec := json.NewDecoder(rd)
-	err := dec.Decode(&idxJSON)
+	err = dec.Decode(&idxJSON)
 	if err != nil {
-		debug.Log("Index.DecodeIndex", "Error %#v", err)
+		debug.Log("Index.DecodeIndex", "Error %v", err)
 
 		if isErrOldIndex(err) {
 			debug.Log("Index.DecodeIndex", "index is probably old format, trying that")
 			err = ErrOldIndexFormat
 		}
 
-		return nil, nil, err
+		return nil, err
 	}
 
-	idx := NewIndex()
+	idx = NewIndex()
 	for _, pack := range idxJSON.Packs {
 		for _, blob := range pack.Blobs {
 			idx.store(blob.Type, blob.ID, &pack.ID, blob.Offset, blob.Length, true)
 		}
 	}
+	idx.supersedes = idxJSON.Supersedes
 
 	debug.Log("Index.DecodeIndex", "done")
-	return idx, idxJSON.Supersedes, err
+	return idx, err
 }
 
 // DecodeOldIndex loads and unserializes an index in the old format from rd.
-func DecodeOldIndex(rd io.Reader) (*Index, backend.IDs, error) {
+func DecodeOldIndex(rd io.Reader) (idx *Index, err error) {
 	debug.Log("Index.DecodeOldIndex", "Start decoding old index")
 	list := []*packJSON{}
 
 	dec := json.NewDecoder(rd)
-	err := dec.Decode(&list)
+	err = dec.Decode(&list)
 	if err != nil {
 		debug.Log("Index.DecodeOldIndex", "Error %#v", err)
-		return nil, nil, err
+		return nil, err
 	}
 
-	idx := NewIndex()
+	idx = NewIndex()
 	for _, pack := range list {
 		for _, blob := range pack.Blobs {
 			idx.store(blob.Type, blob.ID, &pack.ID, blob.Offset, blob.Length, true)
@@ -381,5 +387,76 @@ func DecodeOldIndex(rd io.Reader) (*Index, backend.IDs, error) {
 	}
 
 	debug.Log("Index.DecodeOldIndex", "done")
-	return idx, backend.IDs{}, err
+	return idx, err
+}
+
+// ConvertIndexes loads all indexes from the repo and converts them to the new
+// format (if necessary). When the conversion is succcessful, the old indexes
+// are removed.
+func ConvertIndexes(repo *Repository) error {
+	debug.Log("ConvertIndexes", "start")
+	done := make(chan struct{})
+	defer close(done)
+
+	for id := range repo.List(backend.Index, done) {
+		debug.Log("ConvertIndexes", "checking index %v", id.Str())
+
+		newID, err := ConvertIndex(repo, id)
+		if err != nil {
+			debug.Log("ConvertIndexes", "Converting index %v returns error: %v", id.Str(), err)
+			return err
+		}
+
+		if id != newID {
+			debug.Log("ConvertIndexes", "index %v converted to new format as %v", id.Str(), newID.Str())
+		}
+	}
+
+	debug.Log("ConvertIndexes", "done")
+	return nil
+}
+
+// ConvertIndex loads the given index from the repo and converts them to the new
+// format (if necessary). When the conversion is succcessful, the old index
+// is removed. Returned is either the old id (if no conversion was needed) or
+// the new id.
+func ConvertIndex(repo *Repository, id backend.ID) (backend.ID, error) {
+	debug.Log("ConvertIndex", "checking index %v", id.Str())
+
+	idx, err := LoadIndexWithDecoder(repo, id.String(), DecodeOldIndex)
+	if err != nil {
+		debug.Log("ConvertIndex", "LoadIndexWithDecoder(%v) returned error: %v", id.Str(), err)
+		return id, err
+	}
+
+	blob, err := repo.CreateEncryptedBlob(backend.Index)
+	if err != nil {
+		return id, err
+	}
+
+	idx.supersedes = backend.IDs{id}
+
+	// select all blobs for export
+	err = idx.encode(blob, idx.supersedes, func(e indexEntry) bool { return true })
+	if err != nil {
+		debug.Log("ConvertIndex", "oldIdx.Encode() returned error: %v", err)
+		return id, err
+	}
+
+	err = blob.Close()
+	if err != nil {
+		debug.Log("ConvertIndex", "blob.Close() returned error: %v", err)
+		return id, err
+	}
+
+	newID := blob.ID()
+	debug.Log("ConvertIndex", "index %v converted to new format as %v", id.Str(), newID.Str())
+
+	err = repo.be.Remove(backend.Index, id.String())
+	if err != nil {
+		debug.Log("ConvertIndex", "backend.Remove(%v) returned error: %v", id.Str(), err)
+		return id, err
+	}
+
+	return newID, nil
 }

repository/index_test.go

@@ -3,7 +3,6 @@ package repository_test
 import (
 	"bytes"
 	"crypto/rand"
-	"fmt"
 	"io"
 	"path/filepath"
 	"testing"
@@ -60,7 +59,7 @@ func TestIndexSerialize(t *testing.T) {
 	err := idx.Encode(wr)
 	OK(t, err)
 
-	idx2, _, err := repository.DecodeIndex(wr)
+	idx2, err := repository.DecodeIndex(wr)
 	OK(t, err)
 	Assert(t, idx2 != nil,
 		"nil returned for decoded index")
@@ -115,7 +114,7 @@ func TestIndexSerialize(t *testing.T) {
 	err = idx2.Encode(wr3)
 	OK(t, err)
 
-	idx3, _, err := repository.DecodeIndex(wr3)
+	idx3, err := repository.DecodeIndex(wr3)
 	OK(t, err)
 	Assert(t, idx3 != nil,
 		"nil returned for decoded index")
@@ -246,7 +245,7 @@ var exampleTests = []struct {
 func TestIndexUnserialize(t *testing.T) {
 	oldIdx := backend.IDs{ParseID("ed54ae36197f4745ebc4b54d10e0f623eaaaedd03013eb7ae90df881b7781452")}
 
-	idx, supersedes, err := repository.DecodeIndex(bytes.NewReader(docExample))
+	idx, err := repository.DecodeIndex(bytes.NewReader(docExample))
 	OK(t, err)
 
 	for _, test := range exampleTests {
@@ -259,11 +258,11 @@ func TestIndexUnserialize(t *testing.T) {
 		Equals(t, test.length, length)
 	}
 
-	Equals(t, oldIdx, supersedes)
+	Equals(t, oldIdx, idx.Supersedes())
 }
 
 func TestIndexUnserializeOld(t *testing.T) {
-	idx, supersedes, err := repository.DecodeOldIndex(bytes.NewReader(docOldExample))
+	idx, err := repository.DecodeOldIndex(bytes.NewReader(docOldExample))
 	OK(t, err)
 
 	for _, test := range exampleTests {
@@ -276,8 +275,57 @@ func TestIndexUnserializeOld(t *testing.T) {
 		Equals(t, test.length, length)
 	}
 
-	Assert(t, len(supersedes) == 0,
-		"expected %v supersedes, got %v", 0, len(supersedes))
+	Equals(t, 0, len(idx.Supersedes()))
+}
+
+var oldIndexTestRepo = filepath.Join("testdata", "old-index-repo.tar.gz")
+
+func TestConvertIndex(t *testing.T) {
+	WithTestEnvironment(t, oldIndexTestRepo, func(repodir string) {
+		repo := OpenLocalRepo(t, repodir)
+
+		old := make(map[backend.ID]*repository.Index)
+		for id := range repo.List(backend.Index, nil) {
+			idx, err := repository.LoadIndex(repo, id.String())
+			OK(t, err)
+			old[id] = idx
+		}
+
+		OK(t, repository.ConvertIndexes(repo))
+
+		for id := range repo.List(backend.Index, nil) {
+			idx, err := repository.LoadIndexWithDecoder(repo, id.String(), repository.DecodeIndex)
+			OK(t, err)
+
+			Assert(t, len(idx.Supersedes()) == 1,
+				"Expected index %v to supersed exactly one index, got %v", id, idx.Supersedes())
+
+			oldIndexID := idx.Supersedes()[0]
+
+			oldIndex, ok := old[oldIndexID]
+			Assert(t, ok,
+				"Index %v superseds %v, but that wasn't found in the old index map", id.Str(), oldIndexID.Str())
+
+			Assert(t, idx.Count(pack.Data) == oldIndex.Count(pack.Data),
+				"Index %v count blobs %v: %v != %v", id.Str(), pack.Data, idx.Count(pack.Data), oldIndex.Count(pack.Data))
+			Assert(t, idx.Count(pack.Tree) == oldIndex.Count(pack.Tree),
+				"Index %v count blobs %v: %v != %v", id.Str(), pack.Tree, idx.Count(pack.Tree), oldIndex.Count(pack.Tree))
+
+			for packedBlob := range idx.Each(nil) {
+				packID, tpe, offset, length, err := oldIndex.Lookup(packedBlob.ID)
+				OK(t, err)
+
+				Assert(t, *packID == packedBlob.PackID,
+					"Check blob %v: pack ID %v != %v", packedBlob.ID, packID, packedBlob.PackID)
+				Assert(t, tpe == packedBlob.Type,
+					"Check blob %v: Type %v != %v", packedBlob.ID, tpe, packedBlob.Type)
+				Assert(t, offset == packedBlob.Offset,
+					"Check blob %v: Type %v != %v", packedBlob.ID, offset, packedBlob.Offset)
+				Assert(t, length == packedBlob.Length,
+					"Check blob %v: Type %v != %v", packedBlob.ID, length, packedBlob.Length)
+			}
+		}
+	})
 }
 
 func TestStoreOverwritesPreliminaryEntry(t *testing.T) {

repository/repository.go

@@ -579,14 +579,14 @@ func (r *Repository) LoadIndex() error {
 
 // LoadIndex loads the index id from backend and returns it.
 func LoadIndex(repo *Repository, id string) (*Index, error) {
-	idx, err := loadIndex(repo, id, false)
+	idx, err := LoadIndexWithDecoder(repo, id, DecodeIndex)
 	if err == nil {
 		return idx, nil
 	}
 
 	if err == ErrOldIndexFormat {
-		fmt.Fprintf(os.Stderr, "index %v has old format\n", id)
-		return loadIndex(repo, id, true)
+		fmt.Fprintf(os.Stderr, "index %v has old format\n", id[:10])
+		return LoadIndexWithDecoder(repo, id, DecodeOldIndex)
 	}
 
 	return nil, err
@@ -632,8 +632,9 @@ func (r *Repository) GetDecryptReader(t backend.Type, id string) (io.ReadCloser,
 	return newDecryptReadCloser(r.key, rd)
 }
 
-func loadIndex(repo *Repository, id string, oldFormat bool) (*Index, error) {
-	debug.Log("loadIndex", "Loading index %v", id[:8])
+// LoadIndexWithDecoder loads the index and decodes it with fn.
+func LoadIndexWithDecoder(repo *Repository, id string, fn func(io.Reader) (*Index, error)) (*Index, error) {
+	debug.Log("LoadIndexWithDecoder", "Loading index %v", id[:8])
 
 	rd, err := repo.GetDecryptReader(backend.Index, id)
 	if err != nil {
@@ -641,16 +642,9 @@ func loadIndex(repo *Repository, id string, oldFormat bool) (*Index, error) {
 	}
 	defer rd.Close()
 
-	var idx *Index
-
-	if !oldFormat {
-		idx, _, err = DecodeIndex(rd)
-	} else {
-		idx, _, err = DecodeOldIndex(rd)
-	}
-
+	idx, err := fn(rd)
 	if err != nil {
-		debug.Log("loadIndex", "error while decoding index %v: %v", id, err)
+		debug.Log("LoadIndexWithDecoder", "error while decoding index %v: %v", id, err)
 		return nil, err
 	}
 

repository/repository_test.go

@@ -199,7 +199,7 @@ func TestLoadJSONUnpacked(t *testing.T) {
 
 var repoFixture = filepath.Join("testdata", "test-repo.tar.gz")
 
-func TestLoadIndex(t *testing.T) {
+func TestRepositoryLoadIndex(t *testing.T) {
 	WithTestEnvironment(t, repoFixture, func(repodir string) {
 		repo := OpenLocalRepo(t, repodir)
 		OK(t, repo.LoadIndex())