contracts/chequebook: add chequebook contract wrapper
The wrapper code is adapted from the swarm/services/chequebook package
with the following mostly cosmetic changes:
* The code now uses the new Go API interfaces to query balances. Some
minor functional changes were required to make this work.
* The package no longer depends on swarm/services/swap/swap. References
to swap.Promise are replaced by interface{}, the base type of Promise.
This is temporary.
* The contract wrapper has been regenerated with latest abigen
and solc v0.3.6.
* There is a new generator that creates the 'deployed code' variable.
* Documentation comments now follow the recommended godoc style.
* [CHEQUEBOOK] log prefixes are gone.
* LGPL license headers have been added to all files.
This commit is contained in:
Viktor Trón
Felix Lange
643
contracts/chequebook/cheque.go
Normal file
643
contracts/chequebook/cheque.go
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@ -0,0 +1,643 @@
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// Copyright 2016 The go-ethereum Authors
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// This file is part of the go-ethereum library.
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//
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// The go-ethereum library is free software: you can redistribute it and/or modify
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// it under the terms of the GNU Lesser General Public License as published by
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// the Free Software Foundation, either version 3 of the License, or
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// (at your option) any later version.
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//
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// The go-ethereum library is distributed in the hope that it will be useful,
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// but WITHOUT ANY WARRANTY; without even the implied warranty of
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// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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// GNU Lesser General Public License for more details.
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//
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// You should have received a copy of the GNU Lesser General Public License
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// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
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// Package chequebook package wraps the 'chequebook' Ethereum smart contract.
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//
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// The functions in this package allow using chequebook for
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// issuing, receiving, verifying cheques in ether; (auto)cashing cheques in ether
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// as well as (auto)depositing ether to the chequebook contract.
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package chequebook
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//go:generate abigen --sol contract/chequebook.sol --pkg contract --out contract/chequebook.go
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//go:generate go run ./gencode.go
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import (
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"bytes"
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"crypto/ecdsa"
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"encoding/json"
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"fmt"
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"io/ioutil"
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"math/big"
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"os"
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"sync"
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"time"
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"github.com/ethereum/go-ethereum/accounts/abi/bind"
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"github.com/ethereum/go-ethereum/common"
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"github.com/ethereum/go-ethereum/contracts/chequebook/contract"
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"github.com/ethereum/go-ethereum/core/types"
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"github.com/ethereum/go-ethereum/crypto"
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"github.com/ethereum/go-ethereum/logger"
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"github.com/ethereum/go-ethereum/logger/glog"
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"golang.org/x/net/context"
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)
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// TODO(zelig): watch peer solvency and notify of bouncing cheques
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// TODO(zelig): enable paying with cheque by signing off
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// Some functionality require interacting with the blockchain:
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// * setting current balance on peer's chequebook
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// * sending the transaction to cash the cheque
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// * depositing ether to the chequebook
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// * watching incoming ether
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var (
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gasToCash = big.NewInt(2000000) // gas cost of a cash transaction using chequebook
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// gasToDeploy = big.NewInt(3000000)
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)
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// Backend wraps all methods required for chequebook operation.
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type Backend interface {
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bind.ContractBackend
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TransactionReceipt(ctx context.Context, txHash common.Hash) (*types.Receipt, error)
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BalanceAt(ctx context.Context, address common.Address, blockNum *big.Int) (*big.Int, error)
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}
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// Cheque represents a payment promise to a single beneficiary.
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type Cheque struct {
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Contract common.Address // address of chequebook, needed to avoid cross-contract submission
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Beneficiary common.Address
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Amount *big.Int // cumulative amount of all funds sent
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Sig []byte // signature Sign(Keccak256(contract, beneficiary, amount), prvKey)
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}
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func (self *Cheque) String() string {
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return fmt.Sprintf("contract: %s, beneficiary: %s, amount: %v, signature: %x", self.Contract.Hex(), self.Beneficiary.Hex(), self.Amount, self.Sig)
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}
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type Params struct {
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ContractCode, ContractAbi string
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}
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var ContractParams = &Params{contract.ChequebookBin, contract.ChequebookABI}
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// Chequebook can create and sign cheques from a single contract to multiple beneficiaries.
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// It is the outgoing payment handler for peer to peer micropayments.
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type Chequebook struct {
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path string // path to chequebook file
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prvKey *ecdsa.PrivateKey // private key to sign cheque with
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lock sync.Mutex //
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backend Backend // blockchain API
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quit chan bool // when closed causes autodeposit to stop
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owner common.Address // owner address (derived from pubkey)
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contract *contract.Chequebook // abigen binding
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session *contract.ChequebookSession // abigen binding with Tx Opts
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// persisted fields
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balance *big.Int // not synced with blockchain
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contractAddr common.Address // contract address
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sent map[common.Address]*big.Int //tallies for beneficiarys
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txhash string // tx hash of last deposit tx
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threshold *big.Int // threshold that triggers autodeposit if not nil
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buffer *big.Int // buffer to keep on top of balance for fork protection
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}
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func (self *Chequebook) String() string {
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return fmt.Sprintf("contract: %s, owner: %s, balance: %v, signer: %x", self.contractAddr.Hex(), self.owner.Hex(), self.balance, self.prvKey.PublicKey)
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}
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// NewChequebook creates a new Chequebook.
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func NewChequebook(path string, contractAddr common.Address, prvKey *ecdsa.PrivateKey, backend Backend) (self *Chequebook, err error) {
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balance := new(big.Int)
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sent := make(map[common.Address]*big.Int)
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chbook, err := contract.NewChequebook(contractAddr, backend)
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if err != nil {
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return nil, err
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}
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transactOpts := bind.NewKeyedTransactor(prvKey)
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session := &contract.ChequebookSession{
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Contract: chbook,
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TransactOpts: *transactOpts,
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}
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self = &Chequebook{
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prvKey: prvKey,
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balance: balance,
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contractAddr: contractAddr,
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sent: sent,
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path: path,
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backend: backend,
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owner: transactOpts.From,
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contract: chbook,
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session: session,
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}
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if (contractAddr != common.Address{}) {
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self.setBalanceFromBlockChain()
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glog.V(logger.Detail).Infof("new chequebook initialised from %s (owner: %v, balance: %s)", contractAddr.Hex(), self.owner.Hex(), self.balance.String())
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}
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return
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}
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func (self *Chequebook) setBalanceFromBlockChain() {
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balance, err := self.backend.BalanceAt(context.TODO(), self.contractAddr, nil)
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if err != nil {
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glog.V(logger.Error).Infof("can't get balance: %v", err)
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} else {
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self.balance.Set(balance)
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}
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}
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// LoadChequebook loads a chequebook from disk (file path).
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func LoadChequebook(path string, prvKey *ecdsa.PrivateKey, backend Backend, checkBalance bool) (self *Chequebook, err error) {
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var data []byte
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data, err = ioutil.ReadFile(path)
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if err != nil {
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return
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}
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self, _ = NewChequebook(path, common.Address{}, prvKey, backend)
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err = json.Unmarshal(data, self)
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if err != nil {
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return nil, err
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}
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if checkBalance {
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self.setBalanceFromBlockChain()
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}
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glog.V(logger.Detail).Infof("loaded chequebook (%s, owner: %v, balance: %v) initialised from %v", self.contractAddr.Hex(), self.owner.Hex(), self.balance, path)
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return
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}
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// chequebookFile is the JSON representation of a chequebook.
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type chequebookFile struct {
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Balance string
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Contract string
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Owner string
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Sent map[string]string
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}
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// UnmarshalJSON deserialises a chequebook.
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func (self *Chequebook) UnmarshalJSON(data []byte) error {
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var file chequebookFile
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err := json.Unmarshal(data, &file)
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if err != nil {
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return err
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}
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_, ok := self.balance.SetString(file.Balance, 10)
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if !ok {
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return fmt.Errorf("cumulative amount sent: unable to convert string to big integer: %v", file.Balance)
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}
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self.contractAddr = common.HexToAddress(file.Contract)
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for addr, sent := range file.Sent {
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self.sent[common.HexToAddress(addr)], ok = new(big.Int).SetString(sent, 10)
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if !ok {
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return fmt.Errorf("beneficiary %v cumulative amount sent: unable to convert string to big integer: %v", addr, sent)
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}
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}
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return nil
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}
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// MarshalJSON serialises a chequebook.
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func (self *Chequebook) MarshalJSON() ([]byte, error) {
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var file = &chequebookFile{
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Balance: self.balance.String(),
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Contract: self.contractAddr.Hex(),
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Owner: self.owner.Hex(),
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Sent: make(map[string]string),
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}
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for addr, sent := range self.sent {
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file.Sent[addr.Hex()] = sent.String()
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}
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return json.Marshal(file)
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}
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// Save persists the chequebook on disk, remembering balance, contract address and
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// cumulative amount of funds sent for each beneficiary.
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func (self *Chequebook) Save() (err error) {
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data, err := json.MarshalIndent(self, "", " ")
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if err != nil {
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return err
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}
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glog.V(logger.Detail).Infof("saving chequebook (%s) to %v", self.contractAddr.Hex(), self.path)
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return ioutil.WriteFile(self.path, data, os.ModePerm)
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}
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// Stop quits the autodeposit go routine to terminate
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func (self *Chequebook) Stop() {
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defer self.lock.Unlock()
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self.lock.Lock()
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if self.quit != nil {
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close(self.quit)
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self.quit = nil
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}
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}
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// Issue creates a cheque signed by the chequebook owner's private key. The
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// signer commits to a contract (one that they own), a beneficiary and amount.
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func (self *Chequebook) Issue(beneficiary common.Address, amount *big.Int) (ch *Cheque, err error) {
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defer self.lock.Unlock()
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self.lock.Lock()
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if amount.Cmp(common.Big0) <= 0 {
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return nil, fmt.Errorf("amount must be greater than zero (%v)", amount)
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}
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if self.balance.Cmp(amount) < 0 {
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err = fmt.Errorf("insufficent funds to issue cheque for amount: %v. balance: %v", amount, self.balance)
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} else {
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var sig []byte
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sent, found := self.sent[beneficiary]
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if !found {
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sent = new(big.Int)
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self.sent[beneficiary] = sent
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}
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sum := new(big.Int).Set(sent)
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sum.Add(sum, amount)
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sig, err = crypto.Sign(sigHash(self.contractAddr, beneficiary, sum), self.prvKey)
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if err == nil {
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ch = &Cheque{
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Contract: self.contractAddr,
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Beneficiary: beneficiary,
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Amount: sum,
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Sig: sig,
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}
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sent.Set(sum)
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self.balance.Sub(self.balance, amount) // subtract amount from balance
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}
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}
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// auto deposit if threshold is set and balance is less then threshold
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// note this is called even if issueing cheque fails
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// so we reattempt depositing
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if self.threshold != nil {
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if self.balance.Cmp(self.threshold) < 0 {
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send := new(big.Int).Sub(self.buffer, self.balance)
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self.deposit(send)
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}
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}
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return
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}
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// Cash is a convenience method to cash any cheque.
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func (self *Chequebook) Cash(ch *Cheque) (txhash string, err error) {
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return ch.Cash(self.session)
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}
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// data to sign: contract address, beneficiary, cumulative amount of funds ever sent
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func sigHash(contract, beneficiary common.Address, sum *big.Int) []byte {
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bigamount := sum.Bytes()
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if len(bigamount) > 32 {
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return nil
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}
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var amount32 [32]byte
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copy(amount32[32-len(bigamount):32], bigamount)
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input := append(contract.Bytes(), beneficiary.Bytes()...)
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input = append(input, amount32[:]...)
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return crypto.Keccak256(input)
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}
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// Balance returns the current balance of the chequebook.
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func (self *Chequebook) Balance() *big.Int {
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defer self.lock.Unlock()
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self.lock.Lock()
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return new(big.Int).Set(self.balance)
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}
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// Owner returns the owner account of the chequebook.
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func (self *Chequebook) Owner() common.Address {
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return self.owner
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}
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// Address returns the on-chain contract address of the chequebook.
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func (self *Chequebook) Address() common.Address {
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return self.contractAddr
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}
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// Deposit deposits money to the chequebook account.
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func (self *Chequebook) Deposit(amount *big.Int) (string, error) {
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defer self.lock.Unlock()
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self.lock.Lock()
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return self.deposit(amount)
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}
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// deposit deposits amount to the chequebook account.
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// The caller must hold self.lock.
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func (self *Chequebook) deposit(amount *big.Int) (string, error) {
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// since the amount is variable here, we do not use sessions
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depositTransactor := bind.NewKeyedTransactor(self.prvKey)
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depositTransactor.Value = amount
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chbookRaw := &contract.ChequebookRaw{Contract: self.contract}
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tx, err := chbookRaw.Transfer(depositTransactor)
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if err != nil {
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glog.V(logger.Warn).Infof("error depositing %d wei to chequebook (%s, balance: %v, target: %v): %v", amount, self.contractAddr.Hex(), self.balance, self.buffer, err)
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return "", err
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}
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// assume that transaction is actually successful, we add the amount to balance right away
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self.balance.Add(self.balance, amount)
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glog.V(logger.Detail).Infof("deposited %d wei to chequebook (%s, balance: %v, target: %v)", amount, self.contractAddr.Hex(), self.balance, self.buffer)
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return tx.Hash().Hex(), nil
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}
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// AutoDeposit (re)sets interval time and amount which triggers sending funds to the
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// chequebook. Contract backend needs to be set if threshold is not less than buffer, then
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// deposit will be triggered on every new cheque issued.
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func (self *Chequebook) AutoDeposit(interval time.Duration, threshold, buffer *big.Int) {
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defer self.lock.Unlock()
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self.lock.Lock()
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self.threshold = threshold
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self.buffer = buffer
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self.autoDeposit(interval)
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}
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// autoDeposit starts a goroutine that periodically sends funds to the chequebook
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// contract caller holds the lock the go routine terminates if Chequebook.quit is closed.
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func (self *Chequebook) autoDeposit(interval time.Duration) {
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if self.quit != nil {
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close(self.quit)
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self.quit = nil
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}
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// if threshold >= balance autodeposit after every cheque issued
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if interval == time.Duration(0) || self.threshold != nil && self.buffer != nil && self.threshold.Cmp(self.buffer) >= 0 {
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return
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}
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ticker := time.NewTicker(interval)
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self.quit = make(chan bool)
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quit := self.quit
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go func() {
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FOR:
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for {
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select {
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case <-quit:
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break FOR
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case <-ticker.C:
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self.lock.Lock()
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if self.balance.Cmp(self.buffer) < 0 {
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amount := new(big.Int).Sub(self.buffer, self.balance)
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txhash, err := self.deposit(amount)
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if err == nil {
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self.txhash = txhash
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}
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}
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self.lock.Unlock()
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}
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}
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}()
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return
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}
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// Outbox can issue cheques from a single contract to a single beneficiary.
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type Outbox struct {
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chequeBook *Chequebook
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beneficiary common.Address
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}
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// NewOutbox creates an outbox.
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func NewOutbox(chbook *Chequebook, beneficiary common.Address) *Outbox {
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return &Outbox{chbook, beneficiary}
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}
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// Issue creates cheque.
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func (self *Outbox) Issue(amount *big.Int) (interface{}, error) {
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// TODO(fjl): the return type should be more descriptive.
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return self.chequeBook.Issue(self.beneficiary, amount)
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}
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// AutoDeposit enables auto-deposits on the underlying chequebook.
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func (self *Outbox) AutoDeposit(interval time.Duration, threshold, buffer *big.Int) {
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self.chequeBook.AutoDeposit(interval, threshold, buffer)
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}
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// Stop helps satisfy the swap.OutPayment interface.
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func (self *Outbox) Stop() {}
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// String implements fmt.Stringer.
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func (self *Outbox) String() string {
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return fmt.Sprintf("chequebook: %v, beneficiary: %s, balance: %v", self.chequeBook.Address().Hex(), self.beneficiary.Hex(), self.chequeBook.Balance())
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}
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// Inbox can deposit, verify and cash cheques from a single contract to a single
|
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// beneficiary. It is the incoming payment handler for peer to peer micropayments.
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type Inbox struct {
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lock sync.Mutex
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contract common.Address // peer's chequebook contract
|
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beneficiary common.Address // local peer's receiving address
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||||
sender common.Address // local peer's address to send cashing tx from
|
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signer *ecdsa.PublicKey // peer's public key
|
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txhash string // tx hash of last cashing tx
|
||||
abigen bind.ContractBackend // blockchain API
|
||||
session *contract.ChequebookSession // abi contract backend with tx opts
|
||||
quit chan bool // when closed causes autocash to stop
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||||
maxUncashed *big.Int // threshold that triggers autocashing
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||||
cashed *big.Int // cumulative amount cashed
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||||
cheque *Cheque // last cheque, nil if none yet received
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}
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|
||||
// NewInbox creates an Inbox. An Inboxes is not persisted, the cumulative sum is updated
|
||||
// from blockchain when first cheque is received.
|
||||
func NewInbox(prvKey *ecdsa.PrivateKey, contractAddr, beneficiary common.Address, signer *ecdsa.PublicKey, abigen bind.ContractBackend) (self *Inbox, err error) {
|
||||
if signer == nil {
|
||||
return nil, fmt.Errorf("signer is null")
|
||||
}
|
||||
chbook, err := contract.NewChequebook(contractAddr, abigen)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
transactOpts := bind.NewKeyedTransactor(prvKey)
|
||||
transactOpts.GasLimit = gasToCash
|
||||
session := &contract.ChequebookSession{
|
||||
Contract: chbook,
|
||||
TransactOpts: *transactOpts,
|
||||
}
|
||||
sender := transactOpts.From
|
||||
|
||||
self = &Inbox{
|
||||
contract: contractAddr,
|
||||
beneficiary: beneficiary,
|
||||
sender: sender,
|
||||
signer: signer,
|
||||
session: session,
|
||||
cashed: new(big.Int).Set(common.Big0),
|
||||
}
|
||||
glog.V(logger.Detail).Infof("initialised inbox (%s -> %s) expected signer: %x", self.contract.Hex(), self.beneficiary.Hex(), crypto.FromECDSAPub(signer))
|
||||
return
|
||||
}
|
||||
|
||||
func (self *Inbox) String() string {
|
||||
return fmt.Sprintf("chequebook: %v, beneficiary: %s, balance: %v", self.contract.Hex(), self.beneficiary.Hex(), self.cheque.Amount)
|
||||
}
|
||||
|
||||
// Stop quits the autocash goroutine.
|
||||
func (self *Inbox) Stop() {
|
||||
defer self.lock.Unlock()
|
||||
self.lock.Lock()
|
||||
if self.quit != nil {
|
||||
close(self.quit)
|
||||
self.quit = nil
|
||||
}
|
||||
}
|
||||
|
||||
// Cash attempts to cash the current cheque.
|
||||
func (self *Inbox) Cash() (txhash string, err error) {
|
||||
if self.cheque != nil {
|
||||
txhash, err = self.cheque.Cash(self.session)
|
||||
glog.V(logger.Detail).Infof("cashing cheque (total: %v) on chequebook (%s) sending to %v", self.cheque.Amount, self.contract.Hex(), self.beneficiary.Hex())
|
||||
self.cashed = self.cheque.Amount
|
||||
}
|
||||
return
|
||||
}
|
||||
|
||||
// AutoCash (re)sets maximum time and amount which triggers cashing of the last uncashed
|
||||
// cheque if maxUncashed is set to 0, then autocash on receipt.
|
||||
func (self *Inbox) AutoCash(cashInterval time.Duration, maxUncashed *big.Int) {
|
||||
defer self.lock.Unlock()
|
||||
self.lock.Lock()
|
||||
self.maxUncashed = maxUncashed
|
||||
self.autoCash(cashInterval)
|
||||
}
|
||||
|
||||
// autoCash starts a loop that periodically clears the last check
|
||||
// if the peer is trusted. Clearing period could be 24h or a week.
|
||||
//
|
||||
// The caller must hold self.lock.
|
||||
func (self *Inbox) autoCash(cashInterval time.Duration) {
|
||||
if self.quit != nil {
|
||||
close(self.quit)
|
||||
self.quit = nil
|
||||
}
|
||||
// if maxUncashed is set to 0, then autocash on receipt
|
||||
if cashInterval == time.Duration(0) || self.maxUncashed != nil && self.maxUncashed.Cmp(common.Big0) == 0 {
|
||||
return
|
||||
}
|
||||
|
||||
ticker := time.NewTicker(cashInterval)
|
||||
self.quit = make(chan bool)
|
||||
quit := self.quit
|
||||
go func() {
|
||||
FOR:
|
||||
for {
|
||||
select {
|
||||
case <-quit:
|
||||
break FOR
|
||||
case <-ticker.C:
|
||||
self.lock.Lock()
|
||||
if self.cheque != nil && self.cheque.Amount.Cmp(self.cashed) != 0 {
|
||||
txhash, err := self.Cash()
|
||||
if err == nil {
|
||||
self.txhash = txhash
|
||||
}
|
||||
}
|
||||
self.lock.Unlock()
|
||||
}
|
||||
}
|
||||
}()
|
||||
return
|
||||
}
|
||||
|
||||
// Receive is called to deposit the latest cheque to the incoming Inbox.
|
||||
// The given promise must be a *Cheque.
|
||||
func (self *Inbox) Receive(promise interface{}) (*big.Int, error) {
|
||||
// TODO(fjl): the type of promise should be safer
|
||||
ch := promise.(*Cheque)
|
||||
|
||||
defer self.lock.Unlock()
|
||||
self.lock.Lock()
|
||||
|
||||
var sum *big.Int
|
||||
if self.cheque == nil {
|
||||
// the sum is checked against the blockchain once a check is received
|
||||
tally, err := self.session.Sent(self.beneficiary)
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("inbox: error calling backend to set amount: %v", err)
|
||||
}
|
||||
sum = tally
|
||||
} else {
|
||||
sum = self.cheque.Amount
|
||||
}
|
||||
|
||||
amount, err := ch.Verify(self.signer, self.contract, self.beneficiary, sum)
|
||||
var uncashed *big.Int
|
||||
if err == nil {
|
||||
self.cheque = ch
|
||||
|
||||
if self.maxUncashed != nil {
|
||||
uncashed = new(big.Int).Sub(ch.Amount, self.cashed)
|
||||
if self.maxUncashed.Cmp(uncashed) < 0 {
|
||||
self.Cash()
|
||||
}
|
||||
}
|
||||
glog.V(logger.Detail).Infof("received cheque of %v wei in inbox (%s, uncashed: %v)", amount, self.contract.Hex(), uncashed)
|
||||
}
|
||||
|
||||
return amount, err
|
||||
}
|
||||
|
||||
// Verify verifies cheque for signer, contract, beneficiary, amount, valid signature.
|
||||
func (self *Cheque) Verify(signerKey *ecdsa.PublicKey, contract, beneficiary common.Address, sum *big.Int) (*big.Int, error) {
|
||||
glog.V(logger.Detail).Infof("verify cheque: %v - sum: %v", self, sum)
|
||||
if sum == nil {
|
||||
return nil, fmt.Errorf("invalid amount")
|
||||
}
|
||||
|
||||
if self.Beneficiary != beneficiary {
|
||||
return nil, fmt.Errorf("beneficiary mismatch: %v != %v", self.Beneficiary.Hex(), beneficiary.Hex())
|
||||
}
|
||||
if self.Contract != contract {
|
||||
return nil, fmt.Errorf("contract mismatch: %v != %v", self.Contract.Hex(), contract.Hex())
|
||||
}
|
||||
|
||||
amount := new(big.Int).Set(self.Amount)
|
||||
if sum != nil {
|
||||
amount.Sub(amount, sum)
|
||||
if amount.Cmp(common.Big0) <= 0 {
|
||||
return nil, fmt.Errorf("incorrect amount: %v <= 0", amount)
|
||||
}
|
||||
}
|
||||
|
||||
pubKey, err := crypto.SigToPub(sigHash(self.Contract, beneficiary, self.Amount), self.Sig)
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("invalid signature: %v", err)
|
||||
}
|
||||
if !bytes.Equal(crypto.FromECDSAPub(pubKey), crypto.FromECDSAPub(signerKey)) {
|
||||
return nil, fmt.Errorf("signer mismatch: %x != %x", crypto.FromECDSAPub(pubKey), crypto.FromECDSAPub(signerKey))
|
||||
}
|
||||
return amount, nil
|
||||
}
|
||||
|
||||
// v/r/s representation of signature
|
||||
func sig2vrs(sig []byte) (v byte, r, s [32]byte) {
|
||||
v = sig[64] + 27
|
||||
copy(r[:], sig[:32])
|
||||
copy(s[:], sig[32:64])
|
||||
return
|
||||
}
|
||||
|
||||
// Cash cashes the cheque by sending an Ethereum transaction.
|
||||
func (self *Cheque) Cash(session *contract.ChequebookSession) (string, error) {
|
||||
v, r, s := sig2vrs(self.Sig)
|
||||
tx, err := session.Cash(self.Beneficiary, self.Amount, v, r, s)
|
||||
if err != nil {
|
||||
return "", err
|
||||
}
|
||||
return tx.Hash().Hex(), nil
|
||||
}
|
||||
|
||||
// ValidateCode checks that the on-chain code at address matches the expected chequebook
|
||||
// contract code. This is used to detect suicided chequebooks.
|
||||
func ValidateCode(ctx context.Context, b Backend, address common.Address) (ok bool, err error) {
|
||||
code, err := b.CodeAt(ctx, address, nil)
|
||||
if err != nil {
|
||||
return false, err
|
||||
}
|
||||
return bytes.Equal(code, common.FromHex(contract.ContractDeployedCode)), nil
|
||||
}
|
||||
Reference in New Issue
Block a user