[#973] ir: Listen and process Put/Delete events of Subnet contract

Define notification events, implement parsers. Add morph client of
Subnet contract. Listen, verify and approve events in Inner Ring app.

Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>

pkg/morph/event/subnet/put.go

@@ -0,0 +1,144 @@
+package subnetevents
+
+import (
+	"fmt"
+
+	"github.com/nspcc-dev/neo-go/pkg/core/transaction"
+	"github.com/nspcc-dev/neo-go/pkg/network/payload"
+	"github.com/nspcc-dev/neo-go/pkg/rpc/response/result/subscriptions"
+	"github.com/nspcc-dev/neo-go/pkg/util"
+	"github.com/nspcc-dev/neofs-node/pkg/morph/client"
+	"github.com/nspcc-dev/neofs-node/pkg/morph/event"
+)
+
+// Put structures information about the notification generated by Put method of Subnet contract.
+type Put struct {
+	notaryRequest *payload.P2PNotaryRequest
+
+	txHash util.Uint256
+
+	id []byte
+
+	ownerID []byte
+
+	info []byte
+}
+
+// MorphEvent implements Neo:Morph Event interface.
+func (Put) MorphEvent() {}
+
+// ID returns identifier of the creating subnet in a binary format of NeoFS API protocol.
+func (x Put) ID() []byte {
+	return x.id
+}
+
+// Owner returns subnet owner's ID in a binary format of NeoFS API protocol.
+func (x Put) Owner() []byte {
+	return x.ownerID
+}
+
+// Info returns information about the subnet in a binary format of NeoFS API protocol.
+func (x Put) Info() []byte {
+	return x.info
+}
+
+// TxHash returns hash of the transaction which thrown the notification event.
+// Makes sense only in non-notary environments (see NotaryMainTx).
+func (x Put) TxHash() util.Uint256 {
+	return x.txHash
+}
+
+// NotaryMainTx returns main transaction of the request in the Notary service.
+// Returns nil in non-notary environments.
+func (x Put) NotaryMainTx() *transaction.Transaction {
+	if x.notaryRequest != nil {
+		return x.notaryRequest.MainTransaction
+	}
+
+	return nil
+}
+
+// number of items in notification about subnet creation.
+const itemNumPut = 3
+
+// ParsePut parses the notification about the creation of a subnet which has been thrown
+// by the appropriate method of the subnet contract.
+//
+// Resulting event is of Put type.
+func ParsePut(e *subscriptions.NotificationEvent) (event.Event, error) {
+	var (
+		put Put
+		err error
+	)
+
+	items, err := event.ParseStackArray(e)
+	if err != nil {
+		return nil, fmt.Errorf("parse stack array: %w", err)
+	}
+
+	if ln := len(items); ln != itemNumPut {
+		return nil, event.WrongNumberOfParameters(itemNumPut, ln)
+	}
+
+	// parse ID
+	put.id, err = client.BytesFromStackItem(items[0])
+	if err != nil {
+		return nil, fmt.Errorf("id item: %w", err)
+	}
+
+	// parse owner
+	put.ownerID, err = client.BytesFromStackItem(items[1])
+	if err != nil {
+		return nil, fmt.Errorf("owner item: %w", err)
+	}
+
+	// parse public key
+	put.info, err = client.BytesFromStackItem(items[2])
+	if err != nil {
+		return nil, fmt.Errorf("info item: %w", err)
+	}
+
+	put.txHash = e.Container
+
+	return put, nil
+}
+
+// ParseNotaryPut parses the notary notification about the creation of a subnet which has been
+// thrown by the appropriate method of the subnet contract.
+//
+// Resulting event is of Put type.
+func ParseNotaryPut(e event.NotaryEvent) (event.Event, error) {
+	var put Put
+
+	put.notaryRequest = e.Raw()
+	if put.notaryRequest == nil {
+		panic(fmt.Sprintf("nil %T in notary environment", put.notaryRequest))
+	}
+
+	var (
+		err error
+
+		prms = e.Params()
+	)
+
+	if ln := len(prms); ln != itemNumPut {
+		return nil, event.WrongNumberOfParameters(itemNumPut, ln)
+	}
+
+	put.info, err = event.BytesFromOpcode(prms[0])
+	if err != nil {
+		return nil, fmt.Errorf("info param: %w", err)
+	}
+
+	put.ownerID, err = event.BytesFromOpcode(prms[1])
+	if err != nil {
+		return nil, fmt.Errorf("creator param: %w", err)
+	}
+
+	put.id, err = event.BytesFromOpcode(prms[2])
+	if err != nil {
+		return nil, fmt.Errorf("id param: %w", err)
+	}
+
+	return put, nil
+}