[#327] nns: Simplify code using neo-go v0.99.2

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

ns/nns.go

@@ -2,18 +2,15 @@ package ns
 
 import (
 	"context"
-	"errors"
 	"fmt"
-	"math/big"
 	"net/url"
 
 	"github.com/nspcc-dev/neo-go/pkg/core/state"
 	"github.com/nspcc-dev/neo-go/pkg/neorpc/result"
 	"github.com/nspcc-dev/neo-go/pkg/rpcclient"
-	"github.com/nspcc-dev/neo-go/pkg/smartcontract"
+	"github.com/nspcc-dev/neo-go/pkg/rpcclient/invoker"
+	"github.com/nspcc-dev/neo-go/pkg/rpcclient/unwrap"
 	"github.com/nspcc-dev/neo-go/pkg/util"
-	"github.com/nspcc-dev/neo-go/pkg/vm/stackitem"
-	"github.com/nspcc-dev/neo-go/pkg/vm/vmstate"
 	"github.com/nspcc-dev/neofs-contract/nns"
 	cid "github.com/nspcc-dev/neofs-sdk-go/container/id"
 )
@@ -25,31 +22,9 @@ import (
 type NNS struct {
 	nnsContract util.Uint160
 
-	neoClient neoClient
+	invoker interface {
-}
+		Call(contract util.Uint160, operation string, params ...interface{}) (*result.Invoke, error)
-
+	}
-// represents virtual connection to Neo network used by NNS.Dial.
-type neoClient interface {
-	// calls specified method of the Neo smart contract with provided parameters.
-	call(contract util.Uint160, method string, prm []smartcontract.Parameter) (*result.Invoke, error)
-}
-
-// implements neoClient using Neo HTTP client.
-//
-// note: see NNS.Dial to realize why this isn't defined as type wrapper like neoWebSocket.
-type neoHTTP struct {
-	*rpcclient.Client
-}
-
-func (x *neoHTTP) call(contract util.Uint160, method string, prm []smartcontract.Parameter) (*result.Invoke, error) {
-	return x.Client.InvokeFunction(contract, method, prm, nil)
-}
-
-// implements neoClient using Neo WebSocket client.
-type neoWebSocket rpcclient.WSClient
-
-func (x *neoWebSocket) call(contract util.Uint160, method string, prm []smartcontract.Parameter) (*result.Invoke, error) {
-	return (*rpcclient.WSClient)(x).InvokeFunction(contract, method, prm, nil)
 }
 
 // Dial connects to the address of the NNS server. If fails, the instance
@@ -58,39 +33,30 @@ func (x *neoWebSocket) call(contract util.Uint160, method string, prm []smartcon
 // If URL address scheme is 'ws' or 'wss', then WebSocket protocol is used,
 // otherwise HTTP.
 func (n *NNS) Dial(address string) error {
-	// multiSchemeClient unites neoClient and common interface of
+	// multiSchemeClient unites invoker.RPCInvoke and common interface of
-	// neoclient.Client and neoclient.WSClient. Interface is anonymous
+	// rpcclient.Client and rpcclient.WSClient. Interface is anonymous
 	// according to assumption that common interface of these client types
 	// is not required by design and may diverge with changes.
 	var multiSchemeClient interface {
-		neoClient
+		invoker.RPCInvoke
 		// Init turns client to "ready-to-work" state.
 		Init() error
 		// GetContractStateByID returns state of the NNS contract on 1 input.
 		GetContractStateByID(int32) (*state.Contract, error)
 	}
+	var err error
 
 	uri, err := url.Parse(address)
 	if err == nil && (uri.Scheme == "ws" || uri.Scheme == "wss") {
-		cWebSocket, err := rpcclient.NewWS(context.Background(), address, rpcclient.Options{})
+		multiSchemeClient, err = rpcclient.NewWS(context.Background(), address, rpcclient.Options{})
 		if err != nil {
 			return fmt.Errorf("create Neo WebSocket client: %w", err)
 		}
-
-		multiSchemeClient = (*neoWebSocket)(cWebSocket)
 	} else {
-		cHTTP, err := rpcclient.New(context.Background(), address, rpcclient.Options{})
+		multiSchemeClient, err = rpcclient.New(context.Background(), address, rpcclient.Options{})
 		if err != nil {
 			return fmt.Errorf("create Neo HTTP client: %w", err)
 		}
-
-		// if neoHTTP is defined as type wrapper
-		//   type neoHTTP neoclient.Client
-		// then next assignment causes compilation error
-		//   multiSchemeClient = (*neoHTTP)(cHTTP)
-		multiSchemeClient = &neoHTTP{
-			Client: cHTTP,
-		}
 	}
 
 	if err = multiSchemeClient.Init(); err != nil {
@@ -102,7 +68,7 @@ func (n *NNS) Dial(address string) error {
 		return fmt.Errorf("get NNS contract state: %w", err)
 	}
 
-	n.neoClient = multiSchemeClient
+	n.invoker = invoker.New(multiSchemeClient, nil)
 	n.nnsContract = nnsContract.Hash
 
 	return nil
@@ -116,36 +82,11 @@ func (n *NNS) Dial(address string) error {
 //
 // See also https://docs.neo.org/docs/en-us/reference/nns.html.
 func (n *NNS) ResolveContainerName(name string) (cid.ID, error) {
-	res, err := n.neoClient.call(n.nnsContract, "resolve", []smartcontract.Parameter{
+	arr, err := unwrap.Array(n.invoker.Call(n.nnsContract, "resolve",
-		{
+		name+".container", int64(nns.TXT),
-			Type:  smartcontract.StringType,
+	))
-			Value: name + ".container",
-		},
-		{
-			Type:  smartcontract.IntegerType,
-			Value: big.NewInt(int64(nns.TXT)),
-		},
-	})
 	if err != nil {
-		return cid.ID{}, fmt.Errorf("invoke NNS contract: %w", err)
+		return cid.ID{}, fmt.Errorf("contract invocation: %w", err)
-	}
-
-	if res.State != vmstate.Halt.String() {
-		return cid.ID{}, fmt.Errorf("NNS contract fault exception: %s", res.FaultException)
-	} else if len(res.Stack) == 0 {
-		return cid.ID{}, errors.New("empty stack in invocation result")
-	}
-
-	itemArr, err := res.Stack[len(res.Stack)-1].Convert(stackitem.ArrayT) // top stack element is last in the array
-	if err != nil {
-		return cid.ID{}, fmt.Errorf("convert stack item to %s", stackitem.ArrayT)
-	}
-
-	if _, ok := itemArr.(stackitem.Null); !ok {
-		arr, ok := itemArr.Value().([]stackitem.Item)
-		if !ok {
-			// unexpected for types from stackitem package
-			return cid.ID{}, errors.New("invalid cast to stack item slice")
 	}
 
 	var id cid.ID
@@ -161,7 +102,6 @@ func (n *NNS) ResolveContainerName(name string) (cid.ID, error) {
 			return id, nil
 		}
 	}
-	}
 
 	return cid.ID{}, errNotFound
 }

ns/nns_test.go

@@ -9,11 +9,9 @@ import (
 	"testing"
 
 	"github.com/nspcc-dev/neo-go/pkg/neorpc/result"
-	"github.com/nspcc-dev/neo-go/pkg/smartcontract"
 	"github.com/nspcc-dev/neo-go/pkg/util"
 	"github.com/nspcc-dev/neo-go/pkg/vm/stackitem"
 	"github.com/nspcc-dev/neo-go/pkg/vm/vmstate"
-	"github.com/nspcc-dev/neofs-contract/nns"
 	cidtest "github.com/nspcc-dev/neofs-sdk-go/container/id/test"
 	"github.com/stretchr/testify/require"
 )
@@ -30,18 +28,16 @@ type testNeoClient struct {
 	err error
 }
 
-func (x *testNeoClient) call(contract util.Uint160, method string, prm []smartcontract.Parameter) (*result.Invoke, error) {
+func (x *testNeoClient) Call(contract util.Uint160, operation string, params ...interface{}) (*result.Invoke, error) {
-	require.Equal(x.t, x.expectedContract, contract)
+	var domain string
-	require.Equal(x.t, "resolve", method)
-	require.Len(x.t, prm, 2)
-	require.Equal(x.t, smartcontract.StringType, prm[0].Type)
-	require.Equal(x.t, smartcontract.IntegerType, prm[1].Type)
-	require.EqualValues(x.t, big.NewInt(int64(nns.TXT)), prm[1].Value)
 
-	val, ok := prm[0].Value.(string)
+	require.Equal(x.t, x.expectedContract, contract)
-	require.True(x.t, ok)
+	require.Equal(x.t, "resolve", operation)
-	require.True(x.t, strings.HasSuffix(val, ".container"))
+	require.Len(x.t, params, 2)
-	require.NotEmpty(x.t, strings.TrimSuffix(val, ".container"))
+	require.NotPanics(x.t, func() { domain = params[0].(string) })
+	require.NotPanics(x.t, func() { _ = params[1].(int64) })
+	require.True(x.t, strings.HasSuffix(domain, ".container"))
+	require.NotEmpty(x.t, strings.TrimSuffix(domain, ".container"))
 
 	return &x.res, x.err
 }
@@ -78,14 +74,15 @@ func TestNNS_ResolveContainerName(t *testing.T) {
 
 	n := NNS{
 		nnsContract: nnsContract,
-		neoClient:   testC,
+		invoker:     testC,
 	}
 
 	t.Run("invocation failure", func(t *testing.T) {
-		testC.err = errors.New("invoke err")
+		err1 := errors.New("invoke err")
+		testC.err = err1
 
-		_, err := n.ResolveContainerName(testContainerName)
+		_, err2 := n.ResolveContainerName(testContainerName)
-		require.Error(t, err)
+		require.ErrorIs(t, err2, err1)
 	})
 
 	testC.err = nil