[#705] pkg/morph/netmap: Add `innerRingList` method

Add `innerRingList` method to `netmap` client
wrapper. Method parses current IR nodes list.

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

pkg/morph/client/netmap/client.go

@@ -33,6 +33,7 @@ type Option func(*cfg)
 type cfg struct {
 	addPeerMethod, // add peer method name for invocation
 	newEpochMethod, // new epoch method name for invocation
+	innerRingList, // get innerring list method name for invocation
 	netMapMethod, // get network map method name
 	netMapCandidatesMethod, // get network candidates method name
 	snapshotMethod, // get network map snapshot method name
@@ -48,6 +49,7 @@ const (
 	defaultAddPeerMethod         = "addPeer"          // default add peer method name
 	defaultConfigMethod          = "config"           // default get config value method name
 	defaultEpochMethod           = "epoch"            // default get epoch number method name
+	defaultInnerRingListMethod   = "innerRingList"    // default get innerring list method name
 	defaultNetMapCandidateMethod = "netmapCandidates" // default get network candidates method name
 	defaultNetMapMethod          = "netmap"           // default get network map method name
 	defaultNewEpochMethod        = "newEpoch"         // default new epoch method name
@@ -64,6 +66,7 @@ func defaultConfig() *cfg {
 		addPeerMethod:          defaultAddPeerMethod,
 		configMethod:           defaultConfigMethod,
 		epochMethod:            defaultEpochMethod,
+		innerRingList:          defaultInnerRingListMethod,
 		netMapCandidatesMethod: defaultNetMapCandidateMethod,
 		netMapMethod:           defaultNetMapMethod,
 		newEpochMethod:         defaultNewEpochMethod,

pkg/morph/client/netmap/innerring.go

@@ -1,6 +1,13 @@
 package netmap
 
-import "github.com/nspcc-dev/neo-go/pkg/crypto/keys"
+import (
+	"crypto/elliptic"
+	"fmt"
+
+	"github.com/nspcc-dev/neo-go/pkg/crypto/keys"
+	"github.com/nspcc-dev/neo-go/pkg/vm/stackitem"
+	"github.com/nspcc-dev/neofs-node/pkg/morph/client"
+)
 
 // SetInnerRing updates inner ring members in netmap contract.
 func (c *Client) SetInnerRing(keys keys.PublicKeys) error {
@@ -11,3 +18,60 @@ func (c *Client) SetInnerRing(keys keys.PublicKeys) error {
 
 	return c.client.Invoke(c.setInnerRing, args)
 }
+
+// InnerRingList returns public keys of inner ring members in
+// netmap contract.
+func (c *Client) InnerRingList() (keys.PublicKeys, error) {
+	prms, err := c.client.TestInvoke(
+		c.innerRingList,
+	)
+	if err != nil {
+		return nil, fmt.Errorf("could not perform test invocation (%s): %w", c.innerRingList, err)
+	}
+
+	return irKeysFromStackItem(prms, c.innerRingList)
+}
+
+func irKeysFromStackItem(stack []stackitem.Item, method string) (keys.PublicKeys, error) {
+	if ln := len(stack); ln != 1 {
+		return nil, fmt.Errorf("unexpected stack item count (%s): %d", method, ln)
+	}
+
+	irs, err := client.ArrayFromStackItem(stack[0])
+	if err != nil {
+		return nil, fmt.Errorf("could not get stack item array from stack item (%s): %w", method, err)
+	}
+
+	irKeys := make(keys.PublicKeys, len(irs))
+
+	for i := range irs {
+		irKeys[i], err = irKeyFromStackItem(irs[i])
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	return irKeys, nil
+}
+
+const irNodeFixedPrmNumber = 1
+
+func irKeyFromStackItem(prm stackitem.Item) (*keys.PublicKey, error) {
+	prms, err := client.ArrayFromStackItem(prm)
+	if err != nil {
+		return nil, fmt.Errorf("could not get stack item array (IRNode): %w", err)
+	} else if ln := len(prms); ln != irNodeFixedPrmNumber {
+		return nil, fmt.Errorf(
+			"unexpected stack item count (IRNode): expected %d, has %d",
+			irNodeFixedPrmNumber,
+			ln,
+		)
+	}
+
+	byteKey, err := client.BytesFromStackItem(prms[0])
+	if err != nil {
+		return nil, fmt.Errorf("could not parse bytes from stack item (IRNode): %w", err)
+	}
+
+	return keys.NewPublicKeyFromBytes(byteKey, elliptic.P256())
+}