[#62] morph: List morph rules chains by traversing iterator

* Make `ListMorphRuleChains` methods use `commonclient.ReadIteratorItems`.
* Introduce `ContractStorageActor` interface.
* Iterators are used because listing by `ListChainsByPrefix` may cause
  stack overflow from neo-go side (len(items) > 1024).

Signed-off-by: Airat Arifullin <aarifullin@yadro.com>

go.mod

@@ -3,7 +3,7 @@ module git.frostfs.info/TrueCloudLab/policy-engine
 go 1.20
 
 require (
-	git.frostfs.info/TrueCloudLab/frostfs-contract v0.19.0
+	git.frostfs.info/TrueCloudLab/frostfs-contract v0.19.3-0.20240409111539-e7a05a49ff45
 	github.com/google/uuid v1.3.1
 	github.com/mailru/easyjson v0.7.7
 	github.com/nspcc-dev/neo-go v0.105.0

go.sum

@@ -1,5 +1,5 @@
-git.frostfs.info/TrueCloudLab/frostfs-contract v0.19.0 h1:FzurjElUwC7InY9v5rzXReKbfBL5yRJKSWJPq6BKhH0=
-git.frostfs.info/TrueCloudLab/frostfs-contract v0.19.0/go.mod h1:F/fe1OoIDKr5Bz99q4sriuHDuf3aZefZy9ZsCqEtgxc=
+git.frostfs.info/TrueCloudLab/frostfs-contract v0.19.3-0.20240409111539-e7a05a49ff45 h1:Tp4I+XOLp3VCJORfxSamQtj3RZNISbaLM4WD5iIzXxg=
+git.frostfs.info/TrueCloudLab/frostfs-contract v0.19.3-0.20240409111539-e7a05a49ff45/go.mod h1:F/fe1OoIDKr5Bz99q4sriuHDuf3aZefZy9ZsCqEtgxc=
 github.com/beorn7/perks v1.0.1 h1:VlbKKnNfV8bJzeqoa4cOKqO6bYr3WgKZxO8Z16+hsOM=
 github.com/bits-and-blooms/bitset v1.8.0 h1:FD+XqgOZDUxxZ8hzoBFuV9+cGWY9CslN6d5MS5JVb4c=
 github.com/cespare/xxhash/v2 v2.2.0 h1:DC2CZ1Ep5Y4k3ZQ899DldepgrayRUGE6BBZ/cd9Cj44=

pkg/morph/policy/policy_contract_storage.go

@@ -6,6 +6,7 @@ import (
 	"math/big"
 	"strings"
 
+	"git.frostfs.info/TrueCloudLab/frostfs-contract/commonclient"
 	"git.frostfs.info/TrueCloudLab/frostfs-contract/policy"
 	client "git.frostfs.info/TrueCloudLab/frostfs-contract/rpcclient/policy"
 	"git.frostfs.info/TrueCloudLab/policy-engine/pkg/chain"
@@ -13,6 +14,7 @@ import (
 	"github.com/google/uuid"
 	"github.com/nspcc-dev/neo-go/pkg/neorpc/result"
 	"github.com/nspcc-dev/neo-go/pkg/rpcclient/actor"
+	neoinvoker "github.com/nspcc-dev/neo-go/pkg/rpcclient/invoker"
 	"github.com/nspcc-dev/neo-go/pkg/util"
 	"github.com/nspcc-dev/neo-go/pkg/vm/stackitem"
 	"github.com/nspcc-dev/neo-go/pkg/wallet"
@@ -26,6 +28,10 @@ var (
 
 // ContractStorage is the interface to manage chain rules within Policy contract.
 type ContractStorage struct {
+	hash util.Uint160
+
+	actor ContractStorageActor
+
 	contractInterface *client.Contract
 }
 
@@ -33,23 +39,49 @@ var _ engine.MorphRuleChainStorage = (*ContractStorage)(nil)
 
 // ContractStorageReader is the interface to read data from Policy contract.
 type ContractStorageReader struct {
+	hash util.Uint160
+
+	invoker ContractStorageInvoker
+
 	contractReaderInterface *client.ContractReader
 }
 
+type ContractStorageActor interface {
+	client.Actor
+	GetRPCInvoker() neoinvoker.RPCInvoke
+}
+
 var _ engine.MorphRuleChainStorageReader = (*ContractStorageReader)(nil)
 
-func NewContractStorage(actor client.Actor, contract util.Uint160) *ContractStorage {
+func NewContractStorage(actor ContractStorageActor, contract util.Uint160) *ContractStorage {
 	return &ContractStorage{
+		hash:              contract,
+		actor:             actor,
 		contractInterface: client.New(actor, contract),
 	}
 }
 
+type contractStorageActorImpl struct {
+	client.Actor
+	rpcActor actor.RPCActor
+}
+
+var _ ContractStorageActor = &contractStorageActorImpl{}
+
+func (c *contractStorageActorImpl) GetRPCInvoker() neoinvoker.RPCInvoke {
+	return c.rpcActor
+}
+
+// NewContractStorageWithSimpleActor constructs core actor from `rpcActor`.
+//
+// Note: NewContractStorageWithSimpleActor is appropriate only for call-only-once cases (for example, in CLIs). Otherwise, it is unsafe,
+// because core actor may use invalidated `rpcActor` if some connection errors occurred.
 func NewContractStorageWithSimpleActor(rpcActor actor.RPCActor, acc *wallet.Account, contract util.Uint160) (*ContractStorage, error) {
 	act, err := actor.NewSimple(rpcActor, acc)
 	if err != nil {
 		return nil, fmt.Errorf("failed to create simple actor: %w", err)
 	}
-	return NewContractStorage(act, contract), nil
+	return NewContractStorage(&contractStorageActorImpl{Actor: act, rpcActor: rpcActor}, contract), nil
 }
 
 func (s *ContractStorage) AddMorphRuleChain(name chain.Name, target engine.Target, c *chain.Chain) (txHash util.Uint256, vub uint32, err error) {
@@ -98,17 +130,26 @@ func (s *ContractStorage) RemoveMorphRuleChainsByTarget(name chain.Name, target
 	return
 }
 
-func (s *ContractStorage) ListMorphRuleChains(name chain.Name, target engine.Target) ([]*chain.Chain, error) {
+func listChains(name chain.Name, target engine.Target, rpcInvoker neoinvoker.RPCInvoke, hash util.Uint160) ([]*chain.Chain, error) {
 	kind, err := policyKind(target.Type)
 	if err != nil {
 		return nil, err
 	}
 
-	items, err := s.contractInterface.ListChainsByPrefix(big.NewInt(int64(kind)), target.Name, []byte(name))
-	if err != nil {
-		return nil, err
+	const (
+		method    = "iteratorChainsByPrefix"
+		batchSize = neoinvoker.DefaultIteratorResultItems
+	)
+
+	inv := neoinvoker.New(rpcInvoker, nil)
+	params := []any{
+		big.NewInt(int64(kind)), target.Name, []byte(name),
 	}
 
+	items, err := commonclient.ReadIteratorItems(inv, batchSize, hash, method, params...)
+	if err != nil {
+		return nil, fmt.Errorf("read items error: %w", err)
+	}
 	var chains []*chain.Chain
 	for _, item := range items {
 		serialized, err := bytesFromStackItem(item)
@@ -121,10 +162,13 @@ func (s *ContractStorage) ListMorphRuleChains(name chain.Name, target engine.Tar
 		}
 		chains = append(chains, c)
 	}
-
 	return chains, nil
 }
 
+func (s *ContractStorage) ListMorphRuleChains(name chain.Name, target engine.Target) ([]*chain.Chain, error) {
+	return listChains(name, target, s.actor.GetRPCInvoker(), s.hash)
+}
+
 func (s *ContractStorage) ListTargetsIterator(targetType engine.TargetType) (uuid.UUID, result.Iterator, error) {
 	kind, err := policyKind(targetType)
 	if err != nil {
@@ -141,37 +185,21 @@ func (s *ContractStorage) SetAdmin(addr util.Uint160) (util.Uint256, uint32, err
 	return s.contractInterface.SetAdmin(addr)
 }
 
-func NewContractStorageReader(inv client.Invoker, contract util.Uint160) *ContractStorageReader {
+type ContractStorageInvoker interface {
+	client.Invoker
+	GetRPCInvoker() neoinvoker.RPCInvoke
+}
+
+func NewContractStorageReader(inv ContractStorageInvoker, contract util.Uint160) *ContractStorageReader {
 	return &ContractStorageReader{
+		hash:                    contract,
+		invoker:                 inv,
 		contractReaderInterface: client.NewReader(inv, contract),
 	}
 }
 
 func (s *ContractStorageReader) ListMorphRuleChains(name chain.Name, target engine.Target) ([]*chain.Chain, error) {
-	kind, err := policyKind(target.Type)
-	if err != nil {
-		return nil, err
-	}
-
-	items, err := s.contractReaderInterface.ListChainsByPrefix(big.NewInt(int64(kind)), target.Name, []byte(name))
-	if err != nil {
-		return nil, err
-	}
-
-	var chains []*chain.Chain
-	for _, item := range items {
-		serialized, err := bytesFromStackItem(item)
-		if err != nil {
-			return nil, err
-		}
-		c := new(chain.Chain)
-		if err := c.DecodeBytes(serialized); err != nil {
-			return nil, err
-		}
-		chains = append(chains, c)
-	}
-
-	return chains, nil
+	return listChains(name, target, s.invoker.GetRPCInvoker(), s.hash)
 }
 
 func (s *ContractStorageReader) GetAdmin() (util.Uint160, error) {