[#1085] blobovnicza: allow to ignore errors during iteration

Signed-off-by: Evgenii Stratonikov <evgeniy@nspcc.ru>

pkg/local_object_storage/blobovnicza/iterate.go

@@ -84,6 +84,8 @@ type IteratePrm struct {
 	withoutData bool
 
 	handler IterationHandler
+
+	ignoreErrors bool
 }
 
 // DecodeAddresses sets flag to unmarshal object addresses.
@@ -101,6 +103,11 @@ func (x *IteratePrm) SetHandler(h IterationHandler) {
 	x.handler = h
 }
 
+// IgnoreErrors makes all errors to be ignored.
+func (x *IteratePrm) IgnoreErrors() {
+	x.ignoreErrors = true
+}
+
 // IterateRes groups resulting values of Iterate operation.
 type IterateRes struct {
 }
@@ -124,6 +131,9 @@ func (b *Blobovnicza) Iterate(prm IteratePrm) (*IterateRes, error) {
 					}
 
 					if err := addressFromKey(elem.addr, k); err != nil {
+						if prm.ignoreErrors {
+							return nil
+						}
 						return fmt.Errorf("could not decode address key: %w", err)
 					}
 				}

pkg/local_object_storage/blobovnicza/iterate_test.go

@@ -0,0 +1,57 @@
+package blobovnicza
+
+import (
+	"errors"
+	"path/filepath"
+	"testing"
+
+	"github.com/nspcc-dev/neo-go/pkg/util/slice"
+	objecttest "github.com/nspcc-dev/neofs-sdk-go/object/test"
+	"github.com/stretchr/testify/require"
+	"go.etcd.io/bbolt"
+)
+
+func TestBlobovniczaIterate(t *testing.T) {
+	filename := filepath.Join(t.TempDir(), "blob")
+	b := New(WithPath(filename))
+	require.NoError(t, b.Open())
+	require.NoError(t, b.Init())
+
+	data := [][]byte{{0, 1, 2, 3}, {5, 6, 7, 8}}
+	addr := objecttest.Address()
+	_, err := b.Put(&PutPrm{addr: addr, objData: data[0]})
+	require.NoError(t, err)
+
+	require.NoError(t, b.boltDB.Update(func(tx *bbolt.Tx) error {
+		buck := tx.Bucket(bucketKeyFromBounds(firstBucketBound))
+		return buck.Put([]byte("invalid address"), data[1])
+	}))
+
+	seen := make([][]byte, 0, 2)
+	inc := func(e IterationElement) error {
+		seen = append(seen, slice.Copy(e.data))
+		return nil
+	}
+
+	_, err = b.Iterate(IteratePrm{handler: inc})
+	require.NoError(t, err)
+	require.ElementsMatch(t, seen, data)
+
+	seen = seen[:0]
+	_, err = b.Iterate(IteratePrm{handler: inc, decodeAddresses: true})
+	require.Error(t, err)
+
+	seen = seen[:0]
+	_, err = b.Iterate(IteratePrm{handler: inc, decodeAddresses: true, ignoreErrors: true})
+	require.NoError(t, err)
+	require.ElementsMatch(t, seen, data[:1])
+
+	seen = seen[:0]
+	expectedErr := errors.New("stop iteration")
+	_, err = b.Iterate(IteratePrm{
+		decodeAddresses: true,
+		handler:         func(IterationElement) error { return expectedErr },
+		ignoreErrors:    true,
+	})
+	require.True(t, errors.Is(err, expectedErr), "got: %v")
+}