mirror of
https://github.com/octoleo/restic.git
synced 2024-11-16 10:05:25 +00:00
637 lines
15 KiB
Go
637 lines
15 KiB
Go
package checker_test
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import (
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"context"
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"io"
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"io/ioutil"
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"math/rand"
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"os"
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"path/filepath"
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"sort"
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"strconv"
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"sync"
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"testing"
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"time"
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"github.com/restic/restic/internal/archiver"
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"github.com/restic/restic/internal/checker"
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"github.com/restic/restic/internal/errors"
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"github.com/restic/restic/internal/hashing"
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"github.com/restic/restic/internal/repository"
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"github.com/restic/restic/internal/restic"
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"github.com/restic/restic/internal/test"
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"golang.org/x/sync/errgroup"
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)
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var checkerTestData = filepath.Join("testdata", "checker-test-repo.tar.gz")
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func collectErrors(ctx context.Context, f func(context.Context, chan<- error)) (errs []error) {
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ctx, cancel := context.WithCancel(ctx)
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defer cancel()
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errChan := make(chan error)
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go f(ctx, errChan)
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for err := range errChan {
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errs = append(errs, err)
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}
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return errs
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}
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func checkPacks(chkr *checker.Checker) []error {
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return collectErrors(context.TODO(), chkr.Packs)
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}
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func checkStruct(chkr *checker.Checker) []error {
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err := chkr.LoadSnapshots(context.TODO())
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if err != nil {
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return []error{err}
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}
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return collectErrors(context.TODO(), func(ctx context.Context, errChan chan<- error) {
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chkr.Structure(ctx, nil, errChan)
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})
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}
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func checkData(chkr *checker.Checker) []error {
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return collectErrors(
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context.TODO(),
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func(ctx context.Context, errCh chan<- error) {
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chkr.ReadData(ctx, errCh)
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},
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)
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}
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func assertOnlyMixedPackHints(t *testing.T, hints []error) {
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for _, err := range hints {
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if _, ok := err.(*checker.ErrMixedPack); !ok {
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t.Fatalf("expected mixed pack hint, got %v", err)
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}
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}
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}
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func TestCheckRepo(t *testing.T) {
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repodir, cleanup := test.Env(t, checkerTestData)
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defer cleanup()
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repo := repository.TestOpenLocal(t, repodir)
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chkr := checker.New(repo, false)
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hints, errs := chkr.LoadIndex(context.TODO())
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if len(errs) > 0 {
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t.Fatalf("expected no errors, got %v: %v", len(errs), errs)
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}
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assertOnlyMixedPackHints(t, hints)
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if len(hints) == 0 {
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t.Fatal("expected mixed pack warnings, got none")
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}
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test.OKs(t, checkPacks(chkr))
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test.OKs(t, checkStruct(chkr))
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}
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func TestMissingPack(t *testing.T) {
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repodir, cleanup := test.Env(t, checkerTestData)
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defer cleanup()
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repo := repository.TestOpenLocal(t, repodir)
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packHandle := restic.Handle{
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Type: restic.PackFile,
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Name: "657f7fb64f6a854fff6fe9279998ee09034901eded4e6db9bcee0e59745bbce6",
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}
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test.OK(t, repo.Backend().Remove(context.TODO(), packHandle))
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chkr := checker.New(repo, false)
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hints, errs := chkr.LoadIndex(context.TODO())
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if len(errs) > 0 {
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t.Fatalf("expected no errors, got %v: %v", len(errs), errs)
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}
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assertOnlyMixedPackHints(t, hints)
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errs = checkPacks(chkr)
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test.Assert(t, len(errs) == 1,
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"expected exactly one error, got %v", len(errs))
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if err, ok := errs[0].(*checker.PackError); ok {
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test.Equals(t, packHandle.Name, err.ID.String())
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} else {
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t.Errorf("expected error returned by checker.Packs() to be PackError, got %v", err)
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}
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}
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func TestUnreferencedPack(t *testing.T) {
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repodir, cleanup := test.Env(t, checkerTestData)
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defer cleanup()
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repo := repository.TestOpenLocal(t, repodir)
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// index 3f1a only references pack 60e0
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packID := "60e0438dcb978ec6860cc1f8c43da648170ee9129af8f650f876bad19f8f788e"
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indexHandle := restic.Handle{
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Type: restic.IndexFile,
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Name: "3f1abfcb79c6f7d0a3be517d2c83c8562fba64ef2c8e9a3544b4edaf8b5e3b44",
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}
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test.OK(t, repo.Backend().Remove(context.TODO(), indexHandle))
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chkr := checker.New(repo, false)
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hints, errs := chkr.LoadIndex(context.TODO())
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if len(errs) > 0 {
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t.Fatalf("expected no errors, got %v: %v", len(errs), errs)
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}
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assertOnlyMixedPackHints(t, hints)
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errs = checkPacks(chkr)
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test.Assert(t, len(errs) == 1,
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"expected exactly one error, got %v", len(errs))
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if err, ok := errs[0].(*checker.PackError); ok {
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test.Equals(t, packID, err.ID.String())
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} else {
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t.Errorf("expected error returned by checker.Packs() to be PackError, got %v", err)
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}
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}
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func TestUnreferencedBlobs(t *testing.T) {
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repodir, cleanup := test.Env(t, checkerTestData)
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defer cleanup()
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repo := repository.TestOpenLocal(t, repodir)
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snapshotHandle := restic.Handle{
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Type: restic.SnapshotFile,
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Name: "51d249d28815200d59e4be7b3f21a157b864dc343353df9d8e498220c2499b02",
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}
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test.OK(t, repo.Backend().Remove(context.TODO(), snapshotHandle))
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unusedBlobsBySnapshot := restic.BlobHandles{
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restic.TestParseHandle("58c748bbe2929fdf30c73262bd8313fe828f8925b05d1d4a87fe109082acb849", restic.DataBlob),
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restic.TestParseHandle("988a272ab9768182abfd1fe7d7a7b68967825f0b861d3b36156795832c772235", restic.DataBlob),
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restic.TestParseHandle("c01952de4d91da1b1b80bc6e06eaa4ec21523f4853b69dc8231708b9b7ec62d8", restic.TreeBlob),
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restic.TestParseHandle("bec3a53d7dc737f9a9bee68b107ec9e8ad722019f649b34d474b9982c3a3fec7", restic.TreeBlob),
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restic.TestParseHandle("2a6f01e5e92d8343c4c6b78b51c5a4dc9c39d42c04e26088c7614b13d8d0559d", restic.TreeBlob),
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restic.TestParseHandle("18b51b327df9391732ba7aaf841a4885f350d8a557b2da8352c9acf8898e3f10", restic.DataBlob),
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}
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sort.Sort(unusedBlobsBySnapshot)
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chkr := checker.New(repo, true)
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hints, errs := chkr.LoadIndex(context.TODO())
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if len(errs) > 0 {
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t.Fatalf("expected no errors, got %v: %v", len(errs), errs)
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}
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assertOnlyMixedPackHints(t, hints)
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test.OKs(t, checkPacks(chkr))
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test.OKs(t, checkStruct(chkr))
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blobs := chkr.UnusedBlobs(context.TODO())
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sort.Sort(blobs)
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test.Equals(t, unusedBlobsBySnapshot, blobs)
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}
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func TestModifiedIndex(t *testing.T) {
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repodir, cleanup := test.Env(t, checkerTestData)
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defer cleanup()
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repo := repository.TestOpenLocal(t, repodir)
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done := make(chan struct{})
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defer close(done)
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h := restic.Handle{
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Type: restic.IndexFile,
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Name: "90f838b4ac28735fda8644fe6a08dbc742e57aaf81b30977b4fefa357010eafd",
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}
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tmpfile, err := ioutil.TempFile("", "restic-test-mod-index-")
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if err != nil {
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t.Fatal(err)
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}
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defer func() {
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err := tmpfile.Close()
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if err != nil {
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t.Fatal(err)
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}
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err = os.Remove(tmpfile.Name())
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if err != nil {
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t.Fatal(err)
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}
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}()
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wr := io.Writer(tmpfile)
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var hw *hashing.Writer
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if repo.Backend().Hasher() != nil {
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hw = hashing.NewWriter(wr, repo.Backend().Hasher())
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wr = hw
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}
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// read the file from the backend
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err = repo.Backend().Load(context.TODO(), h, 0, 0, func(rd io.Reader) error {
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_, err := io.Copy(wr, rd)
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return err
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})
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test.OK(t, err)
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// save the index again with a modified name so that the hash doesn't match
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// the content any more
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h2 := restic.Handle{
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Type: restic.IndexFile,
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Name: "80f838b4ac28735fda8644fe6a08dbc742e57aaf81b30977b4fefa357010eafd",
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}
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var hash []byte
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if hw != nil {
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hash = hw.Sum(nil)
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}
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rd, err := restic.NewFileReader(tmpfile, hash)
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if err != nil {
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t.Fatal(err)
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}
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err = repo.Backend().Save(context.TODO(), h2, rd)
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if err != nil {
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t.Fatal(err)
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}
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chkr := checker.New(repo, false)
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hints, errs := chkr.LoadIndex(context.TODO())
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if len(errs) == 0 {
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t.Fatalf("expected errors not found")
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}
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for _, err := range errs {
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t.Logf("found expected error %v", err)
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}
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assertOnlyMixedPackHints(t, hints)
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}
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var checkerDuplicateIndexTestData = filepath.Join("testdata", "duplicate-packs-in-index-test-repo.tar.gz")
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func TestDuplicatePacksInIndex(t *testing.T) {
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repodir, cleanup := test.Env(t, checkerDuplicateIndexTestData)
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defer cleanup()
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repo := repository.TestOpenLocal(t, repodir)
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chkr := checker.New(repo, false)
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hints, errs := chkr.LoadIndex(context.TODO())
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if len(hints) == 0 {
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t.Fatalf("did not get expected checker hints for duplicate packs in indexes")
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}
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found := false
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for _, hint := range hints {
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if _, ok := hint.(*checker.ErrDuplicatePacks); ok {
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found = true
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} else {
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t.Errorf("got unexpected hint: %v", hint)
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}
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}
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if !found {
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t.Fatalf("did not find hint ErrDuplicatePacks")
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}
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if len(errs) > 0 {
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t.Errorf("expected no errors, got %v: %v", len(errs), errs)
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}
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}
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// errorBackend randomly modifies data after reading.
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type errorBackend struct {
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restic.Backend
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ProduceErrors bool
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}
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func (b errorBackend) Load(ctx context.Context, h restic.Handle, length int, offset int64, consumer func(rd io.Reader) error) error {
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return b.Backend.Load(ctx, h, length, offset, func(rd io.Reader) error {
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if b.ProduceErrors {
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return consumer(errorReadCloser{rd})
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}
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return consumer(rd)
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})
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}
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type errorReadCloser struct {
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io.Reader
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}
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func (erd errorReadCloser) Read(p []byte) (int, error) {
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n, err := erd.Reader.Read(p)
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if n > 0 {
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induceError(p[:n])
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}
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return n, err
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}
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// induceError flips a bit in the slice.
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func induceError(data []byte) {
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if rand.Float32() < 0.2 {
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return
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}
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pos := rand.Intn(len(data))
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data[pos] ^= 1
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}
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func TestCheckerModifiedData(t *testing.T) {
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repo, cleanup := repository.TestRepository(t)
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defer cleanup()
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sn := archiver.TestSnapshot(t, repo, ".", nil)
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t.Logf("archived as %v", sn.ID().Str())
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beError := &errorBackend{Backend: repo.Backend()}
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checkRepo := repository.New(beError, repository.Options{})
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test.OK(t, checkRepo.SearchKey(context.TODO(), test.TestPassword, 5, ""))
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chkr := checker.New(checkRepo, false)
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hints, errs := chkr.LoadIndex(context.TODO())
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if len(errs) > 0 {
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t.Fatalf("expected no errors, got %v: %v", len(errs), errs)
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}
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if len(hints) > 0 {
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t.Errorf("expected no hints, got %v: %v", len(hints), hints)
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}
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beError.ProduceErrors = true
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errFound := false
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for _, err := range checkPacks(chkr) {
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t.Logf("pack error: %v", err)
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}
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for _, err := range checkStruct(chkr) {
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t.Logf("struct error: %v", err)
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}
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for _, err := range checkData(chkr) {
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t.Logf("data error: %v", err)
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errFound = true
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}
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if !errFound {
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t.Fatal("no error found, checker is broken")
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}
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}
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// loadTreesOnceRepository allows each tree to be loaded only once
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type loadTreesOnceRepository struct {
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restic.Repository
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loadedTrees restic.IDSet
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mutex sync.Mutex
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DuplicateTree bool
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}
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func (r *loadTreesOnceRepository) LoadTree(ctx context.Context, id restic.ID) (*restic.Tree, error) {
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r.mutex.Lock()
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defer r.mutex.Unlock()
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if r.loadedTrees.Has(id) {
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// additionally store error to ensure that it cannot be swallowed
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r.DuplicateTree = true
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return nil, errors.Errorf("trying to load tree with id %v twice", id)
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}
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r.loadedTrees.Insert(id)
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return restic.LoadTree(ctx, r.Repository, id)
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}
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func TestCheckerNoDuplicateTreeDecodes(t *testing.T) {
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repodir, cleanup := test.Env(t, checkerTestData)
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defer cleanup()
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repo := repository.TestOpenLocal(t, repodir)
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checkRepo := &loadTreesOnceRepository{
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Repository: repo,
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loadedTrees: restic.NewIDSet(),
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}
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chkr := checker.New(checkRepo, false)
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hints, errs := chkr.LoadIndex(context.TODO())
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if len(errs) > 0 {
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t.Fatalf("expected no errors, got %v: %v", len(errs), errs)
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}
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assertOnlyMixedPackHints(t, hints)
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test.OKs(t, checkPacks(chkr))
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test.OKs(t, checkStruct(chkr))
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test.Assert(t, !checkRepo.DuplicateTree, "detected duplicate tree loading")
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}
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// delayRepository delays read of a specific handle.
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type delayRepository struct {
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restic.Repository
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DelayTree restic.ID
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UnblockChannel chan struct{}
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Unblocker sync.Once
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}
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func (r *delayRepository) LoadTree(ctx context.Context, id restic.ID) (*restic.Tree, error) {
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if id == r.DelayTree {
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<-r.UnblockChannel
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}
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return restic.LoadTree(ctx, r.Repository, id)
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}
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func (r *delayRepository) LookupBlobSize(id restic.ID, t restic.BlobType) (uint, bool) {
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if id == r.DelayTree && t == restic.DataBlob {
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r.Unblock()
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}
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return r.Repository.LookupBlobSize(id, t)
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}
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func (r *delayRepository) Unblock() {
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r.Unblocker.Do(func() {
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close(r.UnblockChannel)
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})
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}
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func TestCheckerBlobTypeConfusion(t *testing.T) {
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ctx, cancel := context.WithTimeout(context.Background(), time.Second)
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defer cancel()
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repo, cleanup := repository.TestRepository(t)
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defer cleanup()
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damagedNode := &restic.Node{
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Name: "damaged",
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Type: "file",
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Mode: 0644,
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Size: 42,
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Content: restic.IDs{restic.TestParseID("0123456789abcdef0123456789abcdef0123456789abcdef0123456789abcdef")},
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}
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damagedTree := &restic.Tree{
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Nodes: []*restic.Node{damagedNode},
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}
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wg, wgCtx := errgroup.WithContext(ctx)
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repo.StartPackUploader(wgCtx, wg)
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id, err := restic.SaveTree(ctx, repo, damagedTree)
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test.OK(t, repo.Flush(ctx))
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test.OK(t, err)
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buf, err := repo.LoadBlob(ctx, restic.TreeBlob, id, nil)
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test.OK(t, err)
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wg, wgCtx = errgroup.WithContext(ctx)
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repo.StartPackUploader(wgCtx, wg)
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_, _, _, err = repo.SaveBlob(ctx, restic.DataBlob, buf, id, false)
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test.OK(t, err)
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malNode := &restic.Node{
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Name: "aaaaa",
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Type: "file",
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Mode: 0644,
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Size: uint64(len(buf)),
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Content: restic.IDs{id},
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}
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dirNode := &restic.Node{
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Name: "bbbbb",
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Type: "dir",
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Mode: 0755,
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Subtree: &id,
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}
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rootTree := &restic.Tree{
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Nodes: []*restic.Node{malNode, dirNode},
|
|
}
|
|
|
|
rootID, err := restic.SaveTree(ctx, repo, rootTree)
|
|
test.OK(t, err)
|
|
|
|
test.OK(t, repo.Flush(ctx))
|
|
|
|
snapshot, err := restic.NewSnapshot([]string{"/damaged"}, []string{"test"}, "foo", time.Now())
|
|
test.OK(t, err)
|
|
|
|
snapshot.Tree = &rootID
|
|
|
|
snapID, err := restic.SaveSnapshot(ctx, repo, snapshot)
|
|
test.OK(t, err)
|
|
|
|
t.Logf("saved snapshot %v", snapID.Str())
|
|
|
|
delayRepo := &delayRepository{
|
|
Repository: repo,
|
|
DelayTree: id,
|
|
UnblockChannel: make(chan struct{}),
|
|
}
|
|
|
|
chkr := checker.New(delayRepo, false)
|
|
|
|
go func() {
|
|
<-ctx.Done()
|
|
delayRepo.Unblock()
|
|
}()
|
|
|
|
hints, errs := chkr.LoadIndex(ctx)
|
|
if len(errs) > 0 {
|
|
t.Fatalf("expected no errors, got %v: %v", len(errs), errs)
|
|
}
|
|
|
|
if len(hints) > 0 {
|
|
t.Errorf("expected no hints, got %v: %v", len(hints), hints)
|
|
}
|
|
|
|
errFound := false
|
|
|
|
for _, err := range checkStruct(chkr) {
|
|
t.Logf("struct error: %v", err)
|
|
errFound = true
|
|
}
|
|
|
|
test.OK(t, ctx.Err())
|
|
|
|
if !errFound {
|
|
t.Fatal("no error found, checker is broken")
|
|
}
|
|
}
|
|
|
|
func loadBenchRepository(t *testing.B) (*checker.Checker, restic.Repository, func()) {
|
|
repodir, cleanup := test.Env(t, checkerTestData)
|
|
|
|
repo := repository.TestOpenLocal(t, repodir)
|
|
|
|
chkr := checker.New(repo, false)
|
|
hints, errs := chkr.LoadIndex(context.TODO())
|
|
if len(errs) > 0 {
|
|
defer cleanup()
|
|
t.Fatalf("expected no errors, got %v: %v", len(errs), errs)
|
|
}
|
|
|
|
for _, err := range hints {
|
|
if _, ok := err.(*checker.ErrMixedPack); !ok {
|
|
t.Fatalf("expected mixed pack hint, got %v", err)
|
|
}
|
|
}
|
|
return chkr, repo, cleanup
|
|
}
|
|
|
|
func BenchmarkChecker(t *testing.B) {
|
|
chkr, _, cleanup := loadBenchRepository(t)
|
|
defer cleanup()
|
|
|
|
t.ResetTimer()
|
|
|
|
for i := 0; i < t.N; i++ {
|
|
test.OKs(t, checkPacks(chkr))
|
|
test.OKs(t, checkStruct(chkr))
|
|
test.OKs(t, checkData(chkr))
|
|
}
|
|
}
|
|
|
|
func benchmarkSnapshotScaling(t *testing.B, newSnapshots int) {
|
|
chkr, repo, cleanup := loadBenchRepository(t)
|
|
defer cleanup()
|
|
|
|
snID, err := restic.FindSnapshot(context.TODO(), repo.Backend(), "51d249d2")
|
|
if err != nil {
|
|
t.Fatal(err)
|
|
}
|
|
|
|
sn2, err := restic.LoadSnapshot(context.TODO(), repo, snID)
|
|
if err != nil {
|
|
t.Fatal(err)
|
|
}
|
|
|
|
treeID := sn2.Tree
|
|
|
|
for i := 0; i < newSnapshots; i++ {
|
|
sn, err := restic.NewSnapshot([]string{"test" + strconv.Itoa(i)}, nil, "", time.Now())
|
|
if err != nil {
|
|
t.Fatal(err)
|
|
}
|
|
sn.Tree = treeID
|
|
|
|
_, err = restic.SaveSnapshot(context.TODO(), repo, sn)
|
|
if err != nil {
|
|
t.Fatal(err)
|
|
}
|
|
}
|
|
|
|
t.ResetTimer()
|
|
|
|
for i := 0; i < t.N; i++ {
|
|
test.OKs(t, checkPacks(chkr))
|
|
test.OKs(t, checkStruct(chkr))
|
|
test.OKs(t, checkData(chkr))
|
|
}
|
|
}
|
|
|
|
func BenchmarkCheckerSnapshotScaling(b *testing.B) {
|
|
counts := []int{50, 100, 200}
|
|
for _, count := range counts {
|
|
count := count
|
|
b.Run(strconv.Itoa(count), func(b *testing.B) {
|
|
benchmarkSnapshotScaling(b, count)
|
|
})
|
|
}
|
|
}
|