ir: maintain container placement in container contract

After nspcc-dev/neofs-contract#438 Container contract
now has API for container-side placement/verification operations. But building
placement vectors and updating when needed is still a complex operation that
should be done on a Go application side. This commit adds such a responsibility
for Alphabet nodes. For simplicity, updating is done every epoch and once for
_every_ container if netmap has been changed. Additional optimization can be
considered.

Signed-off-by: Pavel Karpy <carpawell@nspcc.ru>

go.sum

@@ -178,8 +178,8 @@ github.com/nspcc-dev/neo-go/pkg/interop v0.0.0-20240729160116-d8e3e57f88f2 h1:tv
 github.com/nspcc-dev/neo-go/pkg/interop v0.0.0-20240729160116-d8e3e57f88f2/go.mod h1:/vrbWSHc7YS1KSYhVOyyeucXW/e+1DkVBOgnBEXUCeY=
 github.com/nspcc-dev/neofs-api-go/v2 v2.14.1-0.20240827150555-5ce597aa14ea h1:mK0EMGLvunXcFyq7fBURS/CsN4MH+4nlYiqn6pTwWAU=
 github.com/nspcc-dev/neofs-api-go/v2 v2.14.1-0.20240827150555-5ce597aa14ea/go.mod h1:YzhD4EZmC9Z/PNyd7ysC7WXgIgURc9uCG1UWDeV027Y=
-github.com/nspcc-dev/neofs-contract v0.20.0 h1:ARE/3mSN+P9qi/10NBsf7QyPiYrvnxeEgYUN13vHRlo=
-github.com/nspcc-dev/neofs-contract v0.20.0/go.mod h1:YxtKYE/5cMNiqwWcQWzeizbB9jizauLni+p8wXxfhsQ=
+github.com/nspcc-dev/neofs-contract v0.20.1-0.20241203222542-f5a31fd10a31 h1:Lsf6FQ2f2OUAG0D8MobP5k2thsAiCto8+RxsLJ8d//w=
+github.com/nspcc-dev/neofs-contract v0.20.1-0.20241203222542-f5a31fd10a31/go.mod h1:wRKbLECekUTmJRtVH0PhTtiTnEa5uvCU0VRWOq9PY00=
 github.com/nspcc-dev/neofs-sdk-go v1.0.0-rc.12.0.20240809202351-256513c1b29b h1:/7jXQP5pf+M0kRFC1gg5GEdTPkvotpMHxjSXIbMZaGQ=
 github.com/nspcc-dev/neofs-sdk-go v1.0.0-rc.12.0.20240809202351-256513c1b29b/go.mod h1:ewV84r1NACvoBfbKQKzRLUun+Xn5+z9JVqsuCVgv9xI=
 github.com/nspcc-dev/rfc6979 v0.2.3 h1:QNVykGZ3XjFwM/88rGfV3oj4rKNBy+nYI6jM7q19hDI=

pkg/innerring/processors/netmap/cleanup_table.go

@@ -2,6 +2,7 @@ package netmap
 
 import (
 	"bytes"
+	"slices"
 	"sync"
 
 	"github.com/nspcc-dev/neofs-sdk-go/netmap"
@@ -13,6 +14,8 @@ type (
 		enabled    bool
 		threshold  uint64
 		lastAccess map[string]epochStampWithNodeInfo
+
+		prev netmap.NetMap
 	}
 
 	epochStamp struct {
@@ -36,8 +39,9 @@ func newCleanupTable(enabled bool, threshold uint64) cleanupTable {
 	}
 }
 
-// Update cleanup table based on on-chain information about netmap.
-func (c *cleanupTable) update(snapshot netmap.NetMap, now uint64) {
+// Update cleanup table based on on-chain information about netmap. Returned
+// value indicates if the composition of network map memebers has changed.
+func (c *cleanupTable) update(snapshot netmap.NetMap, now uint64) bool {
 	c.Lock()
 	defer c.Unlock()
 
@@ -64,6 +68,14 @@ func (c *cleanupTable) update(snapshot netmap.NetMap, now uint64) {
 	}
 
 	c.lastAccess = newMap
+
+	// order is expected to be the same from epoch to epoch
+	mapChanged := !slices.EqualFunc(c.prev.Nodes(), nmNodes, func(i1 netmap.NodeInfo, i2 netmap.NodeInfo) bool {
+		return bytes.Equal(i1.PublicKey(), i2.PublicKey())
+	})
+	c.prev = snapshot
+
+	return mapChanged
 }
 
 // updates last access time of the netmap node by string public key.

pkg/innerring/processors/netmap/process_epoch.go

@@ -1,11 +1,15 @@
 package netmap
 
 import (
+	"fmt"
+
 	"github.com/nspcc-dev/neofs-node/pkg/innerring/processors/audit"
 	"github.com/nspcc-dev/neofs-node/pkg/innerring/processors/governance"
 	"github.com/nspcc-dev/neofs-node/pkg/innerring/processors/settlement"
 	cntClient "github.com/nspcc-dev/neofs-node/pkg/morph/client/container"
 	netmapEvent "github.com/nspcc-dev/neofs-node/pkg/morph/event/netmap"
+	cid "github.com/nspcc-dev/neofs-sdk-go/container/id"
+	"github.com/nspcc-dev/neofs-sdk-go/netmap"
 	"go.uber.org/zap"
 )
 
@@ -65,14 +69,88 @@ func (np *Processor) processNewEpoch(ev netmapEvent.NewEpoch) {
 		}
 	}
 
-	np.netmapSnapshot.update(*networkMap, epoch)
+	if np.netmapSnapshot.update(*networkMap, epoch) {
+		l.Debug("updating placements in Container contract...")
+		err = np.updatePlacementInContract(*networkMap, l)
+		if err != nil {
+			l.Error("can't update placements in Container contract", zap.Error(err))
+		} else {
+			l.Debug("updated placements in Container contract")
+		}
+	}
 	np.handleCleanupTick(netmapCleanupTick{epoch: epoch, txHash: ev.TxHash()})
 	np.handleNewAudit(audit.NewAuditStartEvent(epoch))
 	np.handleAuditSettlements(settlement.NewAuditEvent(epoch))
 	np.handleAlphabetSync(governance.NewSyncEvent(ev.TxHash()))
 	np.handleNotaryDeposit(ev)
 }
 
+func (np *Processor) updatePlacementInContract(nm netmap.NetMap, l *zap.Logger) error {
+	// TODO: https://github.com/nspcc-dev/neofs-node/issues/3045
+	cids, err := np.containerWrp.List(nil)
+	if err != nil {
+		return fmt.Errorf("can't get containers list: %w", err)
+	}
+
+	for _, cID := range cids {
+		l := l.With(zap.String("cid", cID.String()))
+		l.Debug("updating container placement in Container contract...")
+
+		cnr, err := np.containerWrp.Get(cID[:])
+		if err != nil {
+			l.Error("can't get container to update its placement in Container contract", zap.Error(err))
+			continue
+		}
+
+		policy := cnr.Value.PlacementPolicy()
+
+		vectors, err := nm.ContainerNodes(policy, cID)
+		if err != nil {
+			l.Error("can't build placement vectors for update in Container contract", zap.Error(err))
+			continue
+		}
+
+		err = np.putPlacementVectors(cID, policy, vectors)
+		if err != nil {
+			l.Error("can't put placement vectors to Container contract", zap.Error(err))
+			continue
+		}
+
+		l.Debug("updated container placement in Container contract")
+	}
+
+	return nil
+}
+
+func (np *Processor) putPlacementVectors(cID cid.ID, p netmap.PlacementPolicy, vectors [][]netmap.NodeInfo) error {
+	replicas := make([]uint32, 0, p.NumberOfReplicas())
+
+	for i, vector := range vectors {
+		replicas = append(replicas, p.ReplicaNumberByIndex(i))
+
+		err := np.containerWrp.AddNextEpochNodes(cID[:], i, pubKeys(vector))
+		if err != nil {
+			return fmt.Errorf("can't add %d placement vector to Container contract: %w", i, err)
+		}
+	}
+
+	err := np.containerWrp.CommitContainerListUpdate(cID[:], replicas)
+	if err != nil {
+		return fmt.Errorf("can't commit container list to Container contract: %w", err)
+	}
+
+	return nil
+}
+
+func pubKeys(nodes []netmap.NodeInfo) [][]byte {
+	res := make([][]byte, 0, len(nodes))
+	for _, node := range nodes {
+		res = append(res, node.PublicKey())
+	}
+
+	return res
+}
+
 // Process new epoch tick by invoking new epoch method in network map contract.
 func (np *Processor) processNewEpochTick() {
 	if !np.alphabetState.IsAlphabet() {