package backend import ( "bytes" "context" "io" "io/ioutil" "testing" "github.com/restic/restic/internal/errors" "github.com/restic/restic/internal/mock" "github.com/restic/restic/internal/restic" "github.com/restic/restic/internal/test" ) func TestBackendRetrySeeker(t *testing.T) { be := &mock.Backend{ SaveFn: func(ctx context.Context, h restic.Handle, rd io.Reader) error { return nil }, } retryBackend := RetryBackend{ Backend: be, } data := test.Random(24, 23*14123) type wrapReader struct { io.Reader } var rd io.Reader rd = wrapReader{bytes.NewReader(data)} err := retryBackend.Save(context.TODO(), restic.Handle{}, rd) if err == nil { t.Fatal("did not get expected error for retry backend with non-seeker reader") } rd = bytes.NewReader(data) _, err = io.CopyN(ioutil.Discard, rd, 5) if err != nil { t.Fatal(err) } err = retryBackend.Save(context.TODO(), restic.Handle{}, rd) if err == nil { t.Fatal("did not get expected error for partial reader") } } func TestBackendSaveRetry(t *testing.T) { buf := bytes.NewBuffer(nil) errcount := 0 be := &mock.Backend{ SaveFn: func(ctx context.Context, h restic.Handle, rd io.Reader) error { if errcount == 0 { errcount++ _, err := io.CopyN(ioutil.Discard, rd, 120) if err != nil { return err } return errors.New("injected error") } _, err := io.Copy(buf, rd) return err }, } retryBackend := RetryBackend{ Backend: be, } data := test.Random(23, 5*1024*1024+11241) err := retryBackend.Save(context.TODO(), restic.Handle{}, bytes.NewReader(data)) if err != nil { t.Fatal(err) } if len(data) != buf.Len() { t.Errorf("wrong number of bytes written: want %d, got %d", len(data), buf.Len()) } if !bytes.Equal(data, buf.Bytes()) { t.Errorf("wrong data written to backend") } } func TestBackendListRetry(t *testing.T) { const ( ID1 = "id1" ID2 = "id2" ) retry := 0 be := &mock.Backend{ ListFn: func(ctx context.Context, t restic.FileType, fn func(restic.FileInfo) error) error { // fail during first retry, succeed during second retry++ if retry == 1 { fn(restic.FileInfo{Name: ID1}) return errors.New("test list error") } fn(restic.FileInfo{Name: ID1}) fn(restic.FileInfo{Name: ID2}) return nil }, } retryBackend := RetryBackend{ Backend: be, } var listed []string err := retryBackend.List(context.TODO(), restic.DataFile, func(fi restic.FileInfo) error { listed = append(listed, fi.Name) return nil }) test.OK(t, err) // assert overall success test.Equals(t, 2, retry) // assert retried once test.Equals(t, []string{ID1, ID2}, listed) // assert no duplicate files } // failingReader returns an error after reading limit number of bytes type failingReader struct { data []byte pos int limit int } func (r failingReader) Read(p []byte) (n int, err error) { i := 0 for ; i < len(p) && i+r.pos < r.limit; i++ { p[i] = r.data[r.pos+i] } r.pos += i if r.pos >= r.limit { return i, errors.Errorf("reader reached limit of %d", r.limit) } return i, nil } func (r failingReader) Close() error { return nil } // closingReader adapts io.Reader to io.ReadCloser interface type closingReader struct { rd io.Reader } func (r closingReader) Read(p []byte) (n int, err error) { return r.rd.Read(p) } func (r closingReader) Close() error { return nil } func TestBackendLoadRetry(t *testing.T) { data := test.Random(23, 1024) limit := 100 attempt := 0 be := mock.NewBackend() be.OpenReaderFn = func(ctx context.Context, h restic.Handle, length int, offset int64) (io.ReadCloser, error) { // returns failing reader on first invocation, good reader on subsequent invocations attempt++ if attempt > 1 { return closingReader{rd: bytes.NewReader(data)}, nil } return failingReader{data: data, limit: limit}, nil } retryBackend := RetryBackend{ Backend: be, } var buf []byte err := retryBackend.Load(context.TODO(), restic.Handle{}, 0, 0, func(rd io.Reader) (err error) { buf, err = ioutil.ReadAll(rd) return err }) test.OK(t, err) test.Equals(t, data, buf) test.Equals(t, 2, attempt) }