[#128] innerring: Add GAS pouring mechanism for a configurable list of wallets

Signed-off-by: Artem Tataurov <a.tataurov@yadro.com>

pkg/innerring/innerring.go

@@ -49,7 +49,9 @@ import (
 	"github.com/nspcc-dev/neo-go/pkg/core/block"
 	"github.com/nspcc-dev/neo-go/pkg/core/transaction"
 	"github.com/nspcc-dev/neo-go/pkg/crypto/keys"
+	"github.com/nspcc-dev/neo-go/pkg/encoding/address"
 	"github.com/nspcc-dev/neo-go/pkg/encoding/fixedn"
+	"github.com/nspcc-dev/neo-go/pkg/util"
 	"github.com/panjf2000/ants/v2"
 	"github.com/spf13/viper"
 	"go.uber.org/atomic"
@@ -803,8 +805,14 @@ func New(ctx context.Context, log *logger.Logger, cfg *viper.Viper, errChan chan
 		}
 	}
 
+	parsedWallets, err := parseWalletAddressesFromStrings(cfg.GetStringSlice("emit.extra_wallets"))
+	if err != nil {
+		return nil, err
+	}
+
 	// create alphabet processor
 	alphabetProcessor, err := alphabet.New(&alphabet.Params{
+		ParsedWallets:     parsedWallets,
 		Log:               log,
 		PoolSize:          cfg.GetInt("workers.alphabet"),
 		AlphabetContracts: server.contracts.alphabet,
@@ -1034,6 +1042,24 @@ func ParsePublicKeysFromStrings(pubKeys []string) (keys.PublicKeys, error) {
 	return publicKeys, nil
 }
 
+// parseWalletAddressesFromStrings returns a slice of util.Uint160 from a slice
+// of strings.
+func parseWalletAddressesFromStrings(wallets []string) ([]util.Uint160, error) {
+	if len(wallets) == 0 {
+		return nil, nil
+	}
+
+	var err error
+	extraWallets := make([]util.Uint160, len(wallets))
+	for i := range wallets {
+		extraWallets[i], err = address.StringToUint160(wallets[i])
+		if err != nil {
+			return nil, err
+		}
+	}
+	return extraWallets, nil
+}
+
 func (s *Server) initConfigFromBlockchain() error {
 	// get current epoch
 	epoch, err := s.netmapClient.Epoch()

pkg/innerring/processors/alphabet/process_emit.go

@@ -57,7 +57,7 @@ func (ap *Processor) processEmit() {
 		return
 	}
 
-	gasPerNode := fixedn.Fixed8(ap.storageEmission / uint64(ln))
+	gasPerNode := fixedn.Fixed8(ap.storageEmission / uint64(ln+len(ap.parsedWallets)))
 
 	for i := range nmNodes {
 		keyBytes := nmNodes[i].PublicKey()
@@ -79,4 +79,17 @@ func (ap *Processor) processEmit() {
 			)
 		}
 	}
+
+	err = ap.morphClient.BatchTransferGas(ap.parsedWallets, gasPerNode)
+	if err != nil {
+		receiversLog := make([]string, len(ap.parsedWallets))
+		for i, addr := range ap.parsedWallets {
+			receiversLog[i] = addr.StringLE()
+		}
+		ap.log.Warn("can't transfer gas to wallet",
+			zap.Strings("receivers", receiversLog),
+			zap.Int64("amount", int64(gasPerNode)),
+			zap.String("error", err.Error()),
+		)
+	}
 }

pkg/innerring/processors/alphabet/processor.go

@@ -33,6 +33,7 @@ type (
 
 	// Processor of events produced for alphabet contracts in the sidechain.
 	Processor struct {
+		parsedWallets     []util.Uint160
 		log               *logger.Logger
 		pool              *ants.Pool
 		alphabetContracts Contracts
@@ -44,6 +45,7 @@ type (
 
 	// Params of the processor constructor.
 	Params struct {
+		ParsedWallets     []util.Uint160
 		Log               *logger.Logger
 		PoolSize          int
 		AlphabetContracts Contracts
@@ -73,6 +75,7 @@ func New(p *Params) (*Processor, error) {
 	}
 
 	return &Processor{
+		parsedWallets:     p.ParsedWallets,
 		log:               p.Log,
 		pool:              pool,
 		alphabetContracts: p.AlphabetContracts,

pkg/morph/client/client.go

@@ -244,6 +244,40 @@ func (c *Client) TransferGas(receiver util.Uint160, amount fixedn.Fixed8) error
 	return nil
 }
 
+func (c *Client) BatchTransferGas(receivers []util.Uint160, amount fixedn.Fixed8) error {
+	c.switchLock.RLock()
+	defer c.switchLock.RUnlock()
+
+	if c.inactive {
+		return ErrConnectionLost
+	}
+
+	transferParams := make([]nep17.TransferParameters, len(receivers))
+	receiversLog := make([]string, len(receivers))
+
+	for i, receiver := range receivers {
+		transferParams[i] = nep17.TransferParameters{
+			From:   c.accAddr,
+			To:     receiver,
+			Amount: big.NewInt(int64(amount)),
+			Data:   nil,
+		}
+		receiversLog[i] = receiver.StringLE()
+	}
+
+	txHash, vub, err := c.gasToken.MultiTransfer(transferParams)
+	if err != nil {
+		return err
+	}
+
+	c.logger.Debug("batch gas transfer invoke",
+		zap.Strings("to", receiversLog),
+		zap.Stringer("tx_hash", txHash.Reverse()),
+		zap.Uint32("vub", vub))
+
+	return nil
+}
+
 // Wait function blocks routing execution until there
 // are `n` new blocks in the chain.
 //