[#1731] engine: Add Evacuate command

Make it possible to move all data from 1 shard to other shards.

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

pkg/local_object_storage/engine/evacuate_test.go

@@ -0,0 +1,115 @@
+package engine
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+	"strconv"
+	"testing"
+
+	objectCore "github.com/nspcc-dev/neofs-node/pkg/core/object"
+	"github.com/nspcc-dev/neofs-node/pkg/local_object_storage/blobstor"
+	"github.com/nspcc-dev/neofs-node/pkg/local_object_storage/blobstor/fstree"
+	meta "github.com/nspcc-dev/neofs-node/pkg/local_object_storage/metabase"
+	"github.com/nspcc-dev/neofs-node/pkg/local_object_storage/shard"
+	"github.com/nspcc-dev/neofs-node/pkg/local_object_storage/shard/mode"
+	cidtest "github.com/nspcc-dev/neofs-sdk-go/container/id/test"
+	objectSDK "github.com/nspcc-dev/neofs-sdk-go/object"
+	"github.com/stretchr/testify/require"
+	"go.uber.org/zap/zaptest"
+)
+
+func TestEvacuateShard(t *testing.T) {
+	dir, err := os.MkdirTemp("", "*")
+	require.NoError(t, err)
+	t.Cleanup(func() { _ = os.RemoveAll(dir) })
+
+	e := New(
+		WithLogger(zaptest.NewLogger(t)),
+		WithShardPoolSize(1))
+
+	var ids [3]*shard.ID
+	var fsTree *fstree.FSTree
+
+	for i := range ids {
+		fsTree = fstree.New(
+			fstree.WithPath(filepath.Join(dir, strconv.Itoa(i))),
+			fstree.WithDepth(1))
+
+		ids[i], err = e.AddShard(
+			shard.WithLogger(zaptest.NewLogger(t)),
+			shard.WithBlobStorOptions(
+				blobstor.WithStorages([]blobstor.SubStorage{{
+					Storage: fsTree,
+				}})),
+			shard.WithMetaBaseOptions(
+				meta.WithPath(filepath.Join(dir, fmt.Sprintf("%d.metabase", i))),
+				meta.WithPermissions(0700),
+				meta.WithEpochState(epochState{}),
+			))
+		require.NoError(t, err)
+	}
+	require.NoError(t, e.Open())
+	require.NoError(t, e.Init())
+
+	const objPerShard = 3
+
+	evacuateShardID := ids[2].String()
+
+	objects := make([]*objectSDK.Object, 0, objPerShard*len(ids))
+	for i := 0; ; i++ {
+		objects = append(objects, generateObjectWithCID(t, cidtest.ID()))
+
+		var putPrm PutPrm
+		putPrm.WithObject(objects[i])
+
+		_, err := e.Put(putPrm)
+		require.NoError(t, err)
+
+		res, err := e.shards[evacuateShardID].List()
+		require.NoError(t, err)
+		if len(res.AddressList()) == objPerShard {
+			break
+		}
+	}
+
+	checkHasObjects := func(t *testing.T) {
+		for i := range objects {
+			var prm GetPrm
+			prm.WithAddress(objectCore.AddressOf(objects[i]))
+
+			_, err := e.Get(prm)
+			require.NoError(t, err)
+		}
+	}
+
+	checkHasObjects(t)
+
+	var prm EvacuateShardPrm
+	prm.WithShardID(ids[2])
+
+	t.Run("must be read-only", func(t *testing.T) {
+		res, err := e.Evacuate(prm)
+		require.ErrorIs(t, err, shard.ErrMustBeReadOnly)
+		require.Equal(t, 0, res.Count())
+	})
+
+	require.NoError(t, e.shards[evacuateShardID].SetMode(mode.ReadOnly))
+
+	res, err := e.Evacuate(prm)
+	require.NoError(t, err)
+	require.Equal(t, objPerShard, res.count)
+
+	// We check that all objects are available both before and after shard removal.
+	// First case is a real-world use-case. It ensures that an object can be put in presense
+	// of all metabase checks/marks.
+	// Second case ensures that all objects are indeed moved and available.
+	checkHasObjects(t)
+
+	e.mtx.Lock()
+	delete(e.shards, evacuateShardID)
+	delete(e.shardPools, evacuateShardID)
+	e.mtx.Unlock()
+
+	checkHasObjects(t)
+}