Files
sendico/api/gateway/chain/internal/service/gateway/executor.go
2025-12-26 14:09:16 +01:00

350 lines
11 KiB
Go

package gateway
import (
"context"
"errors"
"math/big"
"strings"
"time"
"github.com/ethereum/go-ethereum"
"github.com/ethereum/go-ethereum/accounts/abi"
"github.com/ethereum/go-ethereum/common"
"github.com/ethereum/go-ethereum/core/types"
"github.com/ethereum/go-ethereum/rpc"
"github.com/shopspring/decimal"
"github.com/tech/sendico/gateway/chain/internal/service/gateway/rpcclient"
"github.com/tech/sendico/gateway/chain/internal/service/gateway/shared"
"go.uber.org/zap"
"github.com/tech/sendico/gateway/chain/internal/keymanager"
"github.com/tech/sendico/gateway/chain/storage/model"
"github.com/tech/sendico/pkg/merrors"
"github.com/tech/sendico/pkg/mlogger"
)
// TransferExecutor handles on-chain submission of transfers.
type TransferExecutor interface {
SubmitTransfer(ctx context.Context, transfer *model.Transfer, source *model.ManagedWallet, destinationAddress string, network shared.Network) (string, error)
AwaitConfirmation(ctx context.Context, network shared.Network, txHash string) (*types.Receipt, error)
}
// NewOnChainExecutor constructs a TransferExecutor that talks to an EVM-compatible chain.
func NewOnChainExecutor(logger mlogger.Logger, keyManager keymanager.Manager, clients *rpcclient.Clients) TransferExecutor {
return &onChainExecutor{
logger: logger.Named("executor"),
keyManager: keyManager,
clients: clients,
}
}
type onChainExecutor struct {
logger mlogger.Logger
keyManager keymanager.Manager
clients *rpcclient.Clients
}
func (o *onChainExecutor) SubmitTransfer(ctx context.Context, transfer *model.Transfer, source *model.ManagedWallet, destinationAddress string, network shared.Network) (string, error) {
if o.keyManager == nil {
o.logger.Warn("Key manager not configured")
return "", executorInternal("key manager is not configured", nil)
}
rpcURL := strings.TrimSpace(network.RPCURL)
if rpcURL == "" {
o.logger.Warn("Network rpc url missing", zap.String("network", network.Name))
return "", executorInvalid("network rpc url is not configured")
}
if source == nil || transfer == nil {
o.logger.Warn("Transfer context missing")
return "", executorInvalid("transfer context missing")
}
if strings.TrimSpace(source.KeyReference) == "" {
o.logger.Warn("Source wallet missing key reference", zap.String("wallet_ref", source.WalletRef))
return "", executorInvalid("source wallet missing key reference")
}
if strings.TrimSpace(source.DepositAddress) == "" {
o.logger.Warn("Source wallet missing deposit address", zap.String("wallet_ref", source.WalletRef))
return "", executorInvalid("source wallet missing deposit address")
}
if !common.IsHexAddress(destinationAddress) {
o.logger.Warn("Invalid destination address", zap.String("transfer_ref", transfer.TransferRef), zap.String("address", destinationAddress))
return "", executorInvalid("invalid destination address " + destinationAddress)
}
o.logger.Info("Submitting transfer",
zap.String("transfer_ref", transfer.TransferRef),
zap.String("source_wallet_ref", source.WalletRef),
zap.String("network", network.Name),
zap.String("destination", strings.ToLower(destinationAddress)),
)
client, err := o.clients.Client(network.Name)
if err != nil {
o.logger.Warn("Failed to initialise RPC client", zap.Error(err), zap.String("network", network.Name))
return "", err
}
rpcClient, err := o.clients.RPCClient(network.Name)
if err != nil {
o.logger.Warn("Failed to initialise RPC client",
zap.String("network", network.Name),
zap.Error(err),
)
return "", err
}
sourceAddress := common.HexToAddress(source.DepositAddress)
destination := common.HexToAddress(destinationAddress)
ctx, cancel := context.WithTimeout(ctx, 60*time.Second)
defer cancel()
nonce, err := client.PendingNonceAt(ctx, sourceAddress)
if err != nil {
o.logger.Warn("Failed to fetch nonce", zap.Error(err),
zap.String("transfer_ref", transfer.TransferRef),
zap.String("wallet_ref", source.WalletRef),
)
return "", executorInternal("failed to fetch nonce", err)
}
gasPrice, err := client.SuggestGasPrice(ctx)
if err != nil {
o.logger.Warn("Failed to suggest gas price",
zap.String("transfer_ref", transfer.TransferRef),
zap.String("network", network.Name),
zap.Error(err),
)
return "", executorInternal("failed to suggest gas price", err)
}
var tx *types.Transaction
var txHash string
chainID := new(big.Int).SetUint64(network.ChainID)
if strings.TrimSpace(transfer.ContractAddress) == "" {
o.logger.Warn("Native token transfer requested but not supported", zap.String("transfer_ref", transfer.TransferRef))
return "", merrors.NotImplemented("executor: native token transfers not yet supported")
}
if !common.IsHexAddress(transfer.ContractAddress) {
o.logger.Warn("Invalid token contract address",
zap.String("transfer_ref", transfer.TransferRef),
zap.String("contract", transfer.ContractAddress),
)
return "", executorInvalid("invalid token contract address " + transfer.ContractAddress)
}
tokenAddress := common.HexToAddress(transfer.ContractAddress)
decimals, err := erc20Decimals(ctx, rpcClient, tokenAddress)
if err != nil {
o.logger.Warn("Failed to read token decimals", zap.Error(err),
zap.String("transfer_ref", transfer.TransferRef),
zap.String("contract", transfer.ContractAddress),
)
return "", err
}
amount := transfer.NetAmount
if amount == nil || strings.TrimSpace(amount.Amount) == "" {
o.logger.Warn("Transfer missing net amount", zap.String("transfer_ref", transfer.TransferRef))
return "", executorInvalid("transfer missing net amount")
}
amountInt, err := toBaseUnits(amount.Amount, decimals)
if err != nil {
o.logger.Warn("Failed to convert amount to base units", zap.Error(err),
zap.String("transfer_ref", transfer.TransferRef),
zap.String("amount", amount.Amount),
)
return "", err
}
input, err := erc20ABI.Pack("transfer", destination, amountInt)
if err != nil {
o.logger.Warn("Failed to encode transfer call",
zap.String("transfer_ref", transfer.TransferRef),
zap.Error(err),
)
return "", executorInternal("failed to encode transfer call", err)
}
callMsg := ethereum.CallMsg{
From: sourceAddress,
To: &tokenAddress,
GasPrice: gasPrice,
Data: input,
}
gasLimit, err := client.EstimateGas(ctx, callMsg)
if err != nil {
o.logger.Warn("Failed to estimate gas",
zap.String("transfer_ref", transfer.TransferRef),
zap.Error(err),
)
return "", executorInternal("failed to estimate gas", err)
}
tx = types.NewTransaction(nonce, tokenAddress, big.NewInt(0), gasLimit, gasPrice, input)
signedTx, err := o.keyManager.SignTransaction(ctx, source.KeyReference, tx, chainID)
if err != nil {
o.logger.Warn("Failed to sign transaction", zap.Error(err),
zap.String("transfer_ref", transfer.TransferRef),
zap.String("wallet_ref", source.WalletRef),
)
return "", err
}
if err := client.SendTransaction(ctx, signedTx); err != nil {
o.logger.Warn("Failed to send transaction", zap.Error(err),
zap.String("transfer_ref", transfer.TransferRef),
)
return "", executorInternal("failed to send transaction", err)
}
txHash = signedTx.Hash().Hex()
o.logger.Info("Transaction submitted",
zap.String("transfer_ref", transfer.TransferRef),
zap.String("tx_hash", txHash),
zap.String("network", network.Name),
)
return txHash, nil
}
func (o *onChainExecutor) AwaitConfirmation(ctx context.Context, network shared.Network, txHash string) (*types.Receipt, error) {
if strings.TrimSpace(txHash) == "" {
o.logger.Warn("Missing transaction hash for confirmation", zap.String("network", network.Name))
return nil, executorInvalid("tx hash is required")
}
rpcURL := strings.TrimSpace(network.RPCURL)
if rpcURL == "" {
o.logger.Warn("Network RPC url missing while awaiting confirmation", zap.String("tx_hash", txHash))
return nil, executorInvalid("network rpc url is not configured")
}
client, err := o.clients.Client(network.Name)
if err != nil {
return nil, err
}
hash := common.HexToHash(txHash)
ticker := time.NewTicker(3 * time.Second)
defer ticker.Stop()
for {
receipt, err := client.TransactionReceipt(ctx, hash)
if err != nil {
if errors.Is(err, ethereum.NotFound) {
select {
case <-ticker.C:
o.logger.Debug("Transaction not yet mined",
zap.String("tx_hash", txHash),
zap.String("network", network.Name),
)
continue
case <-ctx.Done():
o.logger.Warn("Context cancelled while awaiting confirmation",
zap.String("tx_hash", txHash),
zap.String("network", network.Name),
)
return nil, ctx.Err()
}
}
o.logger.Warn("Failed to fetch transaction receipt",
zap.String("tx_hash", txHash),
zap.String("network", network.Name),
zap.Error(err),
)
return nil, executorInternal("failed to fetch transaction receipt", err)
}
o.logger.Info("Transaction confirmed",
zap.String("tx_hash", txHash),
zap.String("network", network.Name),
zap.Uint64("block_number", receipt.BlockNumber.Uint64()),
zap.Uint64("status", receipt.Status),
)
return receipt, nil
}
}
var (
erc20ABI abi.ABI
)
func init() {
var err error
erc20ABI, err = abi.JSON(strings.NewReader(erc20ABIJSON))
if err != nil {
panic("executor: failed to parse erc20 abi: " + err.Error())
}
}
const erc20ABIJSON = `
[
{
"constant": false,
"inputs": [
{ "name": "_to", "type": "address" },
{ "name": "_value", "type": "uint256" }
],
"name": "transfer",
"outputs": [{ "name": "", "type": "bool" }],
"payable": false,
"stateMutability": "nonpayable",
"type": "function"
},
{
"constant": true,
"inputs": [],
"name": "decimals",
"outputs": [{ "name": "", "type": "uint8" }],
"payable": false,
"stateMutability": "view",
"type": "function"
}
]`
func erc20Decimals(ctx context.Context, client *rpc.Client, token common.Address) (uint8, error) {
call := map[string]string{
"to": strings.ToLower(token.Hex()),
"data": "0x313ce567",
}
var hexResp string
if err := client.CallContext(ctx, &hexResp, "eth_call", call, "latest"); err != nil {
return 0, executorInternal("decimals call failed", err)
}
val, err := shared.DecodeHexUint8(hexResp)
if err != nil {
return 0, executorInternal("decimals decode failed", err)
}
return val, nil
}
func toBaseUnits(amount string, decimals uint8) (*big.Int, error) {
value, err := decimal.NewFromString(strings.TrimSpace(amount))
if err != nil {
return nil, executorInvalid("invalid amount " + amount + ": " + err.Error())
}
if value.IsNegative() {
return nil, executorInvalid("amount must be positive")
}
multiplier := decimal.NewFromInt(1).Shift(int32(decimals))
scaled := value.Mul(multiplier)
if !scaled.Equal(scaled.Truncate(0)) {
return nil, executorInvalid("amount " + amount + " exceeds token precision")
}
return scaled.BigInt(), nil
}
func executorInvalid(msg string) error {
return merrors.InvalidArgument("executor: " + msg)
}
func executorInternal(msg string, err error) error {
if err != nil {
msg = msg + ": " + err.Error()
}
return merrors.Internal("executor: " + msg)
}