roysc/plugeth
1
0
Fork 0
forked from cerc-io/plugeth
Code Pull Requests Activity

Merge pull request #2956 from fjl/chequebook

Browse Source 
contracts/chequebook: add chequebook contract wrapper
This commit is contained in:
Felix Lange 2016-08-29 14:06:12 +02:00 committed by GitHub
commit 3b087e03ea
7 changed files with 1930 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

68
contracts/chequebook/api.go Normal file
View File

@ -0,0 +1,68 @@
// Copyright 2016 The go-ethereum Authors
// This file is part of the go-ethereum library.
//
// The go-ethereum library is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// The go-ethereum library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
package chequebook
import (
"errors"
"math/big"
"github.com/ethereum/go-ethereum/common"
)
const Version = "1.0"
var errNoChequebook = errors.New("no chequebook")
type Api struct {
chequebookf func() *Chequebook
}
func NewApi(ch func() *Chequebook) *Api {
return &Api{ch}
}
func (self *Api) Balance() (string, error) {
ch := self.chequebookf()
if ch == nil {
return "", errNoChequebook
}
return ch.Balance().String(), nil
}
func (self *Api) Issue(beneficiary common.Address, amount *big.Int) (cheque *Cheque, err error) {
ch := self.chequebookf()
if ch == nil {
return nil, errNoChequebook
}
return ch.Issue(beneficiary, amount)
}
func (self *Api) Cash(cheque *Cheque) (txhash string, err error) {
ch := self.chequebookf()
if ch == nil {
return "", errNoChequebook
}
return ch.Cash(cheque)
}
func (self *Api) Deposit(amount *big.Int) (txhash string, err error) {
ch := self.chequebookf()
if ch == nil {
return "", errNoChequebook
}
return ch.Deposit(amount)
}

643
contracts/chequebook/cheque.go Normal file
View File

@ -0,0 +1,643 @@
// Copyright 2016 The go-ethereum Authors
// This file is part of the go-ethereum library.
//
// The go-ethereum library is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// The go-ethereum library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
// Package chequebook package wraps the 'chequebook' Ethereum smart contract.
//
// The functions in this package allow using chequebook for
// issuing, receiving, verifying cheques in ether; (auto)cashing cheques in ether
// as well as (auto)depositing ether to the chequebook contract.
package chequebook
//go:generate abigen --sol contract/chequebook.sol --pkg contract --out contract/chequebook.go
//go:generate go run ./gencode.go
import (
"bytes"
"crypto/ecdsa"
"encoding/json"
"fmt"
"io/ioutil"
"math/big"
"os"
"sync"
"time"
"github.com/ethereum/go-ethereum/accounts/abi/bind"
"github.com/ethereum/go-ethereum/common"
"github.com/ethereum/go-ethereum/contracts/chequebook/contract"
"github.com/ethereum/go-ethereum/core/types"
"github.com/ethereum/go-ethereum/crypto"
"github.com/ethereum/go-ethereum/logger"
"github.com/ethereum/go-ethereum/logger/glog"
"golang.org/x/net/context"
)
// TODO(zelig): watch peer solvency and notify of bouncing cheques
// TODO(zelig): enable paying with cheque by signing off
// Some functionality require interacting with the blockchain:
// * setting current balance on peer's chequebook
// * sending the transaction to cash the cheque
// * depositing ether to the chequebook
// * watching incoming ether
var (
gasToCash = big.NewInt(2000000) // gas cost of a cash transaction using chequebook
// gasToDeploy = big.NewInt(3000000)
)
// Backend wraps all methods required for chequebook operation.
type Backend interface {
bind.ContractBackend
TransactionReceipt(ctx context.Context, txHash common.Hash) (*types.Receipt, error)
BalanceAt(ctx context.Context, address common.Address, blockNum *big.Int) (*big.Int, error)
}
// Cheque represents a payment promise to a single beneficiary.
type Cheque struct {
Contract common.Address // address of chequebook, needed to avoid cross-contract submission
Beneficiary common.Address
Amount *big.Int // cumulative amount of all funds sent
Sig []byte // signature Sign(Keccak256(contract, beneficiary, amount), prvKey)
}
func (self *Cheque) String() string {
return fmt.Sprintf("contract: %s, beneficiary: %s, amount: %v, signature: %x", self.Contract.Hex(), self.Beneficiary.Hex(), self.Amount, self.Sig)
}
type Params struct {
ContractCode, ContractAbi string
}
var ContractParams = &Params{contract.ChequebookBin, contract.ChequebookABI}
// Chequebook can create and sign cheques from a single contract to multiple beneficiaries.
// It is the outgoing payment handler for peer to peer micropayments.
type Chequebook struct {
path string // path to chequebook file
prvKey *ecdsa.PrivateKey // private key to sign cheque with
lock sync.Mutex //
backend Backend // blockchain API
quit chan bool // when closed causes autodeposit to stop
owner common.Address // owner address (derived from pubkey)
contract *contract.Chequebook // abigen binding
session *contract.ChequebookSession // abigen binding with Tx Opts
// persisted fields
balance *big.Int // not synced with blockchain
contractAddr common.Address // contract address
sent map[common.Address]*big.Int //tallies for beneficiarys
txhash string // tx hash of last deposit tx
threshold *big.Int // threshold that triggers autodeposit if not nil
buffer *big.Int // buffer to keep on top of balance for fork protection
}
func (self *Chequebook) String() string {
return fmt.Sprintf("contract: %s, owner: %s, balance: %v, signer: %x", self.contractAddr.Hex(), self.owner.Hex(), self.balance, self.prvKey.PublicKey)
}
// NewChequebook creates a new Chequebook.
func NewChequebook(path string, contractAddr common.Address, prvKey *ecdsa.PrivateKey, backend Backend) (self *Chequebook, err error) {
balance := new(big.Int)
sent := make(map[common.Address]*big.Int)
chbook, err := contract.NewChequebook(contractAddr, backend)
if err != nil {
return nil, err
}
transactOpts := bind.NewKeyedTransactor(prvKey)
session := &contract.ChequebookSession{
Contract: chbook,
TransactOpts: *transactOpts,
}
self = &Chequebook{
prvKey: prvKey,
balance: balance,
contractAddr: contractAddr,
sent: sent,
path: path,
backend: backend,
owner: transactOpts.From,
contract: chbook,
session: session,
}
if (contractAddr != common.Address{}) {
self.setBalanceFromBlockChain()
glog.V(logger.Detail).Infof("new chequebook initialised from %s (owner: %v, balance: %s)", contractAddr.Hex(), self.owner.Hex(), self.balance.String())
}
return
}
func (self *Chequebook) setBalanceFromBlockChain() {
balance, err := self.backend.BalanceAt(context.TODO(), self.contractAddr, nil)
if err != nil {
glog.V(logger.Error).Infof("can't get balance: %v", err)
} else {
self.balance.Set(balance)
}
}
// LoadChequebook loads a chequebook from disk (file path).
func LoadChequebook(path string, prvKey *ecdsa.PrivateKey, backend Backend, checkBalance bool) (self *Chequebook, err error) {
var data []byte
data, err = ioutil.ReadFile(path)
if err != nil {
return
}
self, _ = NewChequebook(path, common.Address{}, prvKey, backend)
err = json.Unmarshal(data, self)
if err != nil {
return nil, err
}
if checkBalance {
self.setBalanceFromBlockChain()
}
glog.V(logger.Detail).Infof("loaded chequebook (%s, owner: %v, balance: %v) initialised from %v", self.contractAddr.Hex(), self.owner.Hex(), self.balance, path)
return
}
// chequebookFile is the JSON representation of a chequebook.
type chequebookFile struct {
Balance string
Contract string
Owner string
Sent map[string]string
}
// UnmarshalJSON deserialises a chequebook.
func (self *Chequebook) UnmarshalJSON(data []byte) error {
var file chequebookFile
err := json.Unmarshal(data, &file)
if err != nil {
return err
}
_, ok := self.balance.SetString(file.Balance, 10)
if !ok {
return fmt.Errorf("cumulative amount sent: unable to convert string to big integer: %v", file.Balance)
}
self.contractAddr = common.HexToAddress(file.Contract)
for addr, sent := range file.Sent {
self.sent[common.HexToAddress(addr)], ok = new(big.Int).SetString(sent, 10)
if !ok {
return fmt.Errorf("beneficiary %v cumulative amount sent: unable to convert string to big integer: %v", addr, sent)
}
}
return nil
}
// MarshalJSON serialises a chequebook.
func (self *Chequebook) MarshalJSON() ([]byte, error) {
var file = &chequebookFile{
Balance: self.balance.String(),
Contract: self.contractAddr.Hex(),
Owner: self.owner.Hex(),
Sent: make(map[string]string),
}
for addr, sent := range self.sent {
file.Sent[addr.Hex()] = sent.String()
}
return json.Marshal(file)
}
// Save persists the chequebook on disk, remembering balance, contract address and
// cumulative amount of funds sent for each beneficiary.
func (self *Chequebook) Save() (err error) {
data, err := json.MarshalIndent(self, "", " ")
if err != nil {
return err
}
glog.V(logger.Detail).Infof("saving chequebook (%s) to %v", self.contractAddr.Hex(), self.path)
return ioutil.WriteFile(self.path, data, os.ModePerm)
}
// Stop quits the autodeposit go routine to terminate
func (self *Chequebook) Stop() {
defer self.lock.Unlock()
self.lock.Lock()
if self.quit != nil {
close(self.quit)
self.quit = nil
}
}
// Issue creates a cheque signed by the chequebook owner's private key. The
// signer commits to a contract (one that they own), a beneficiary and amount.
func (self *Chequebook) Issue(beneficiary common.Address, amount *big.Int) (ch *Cheque, err error) {
defer self.lock.Unlock()
self.lock.Lock()
if amount.Cmp(common.Big0) <= 0 {
return nil, fmt.Errorf("amount must be greater than zero (%v)", amount)
}
if self.balance.Cmp(amount) < 0 {
err = fmt.Errorf("insufficent funds to issue cheque for amount: %v. balance: %v", amount, self.balance)
} else {
var sig []byte
sent, found := self.sent[beneficiary]
if !found {
sent = new(big.Int)
self.sent[beneficiary] = sent
}
sum := new(big.Int).Set(sent)
sum.Add(sum, amount)
sig, err = crypto.Sign(sigHash(self.contractAddr, beneficiary, sum), self.prvKey)
if err == nil {
ch = &Cheque{
Contract: self.contractAddr,
Beneficiary: beneficiary,
Amount: sum,
Sig: sig,
}
sent.Set(sum)
self.balance.Sub(self.balance, amount) // subtract amount from balance
}
}
// auto deposit if threshold is set and balance is less then threshold
// note this is called even if issueing cheque fails
// so we reattempt depositing
if self.threshold != nil {
if self.balance.Cmp(self.threshold) < 0 {
send := new(big.Int).Sub(self.buffer, self.balance)
self.deposit(send)
}
}
return
}
// Cash is a convenience method to cash any cheque.
func (self *Chequebook) Cash(ch *Cheque) (txhash string, err error) {
return ch.Cash(self.session)
}
// data to sign: contract address, beneficiary, cumulative amount of funds ever sent
func sigHash(contract, beneficiary common.Address, sum *big.Int) []byte {
bigamount := sum.Bytes()
if len(bigamount) > 32 {
return nil
}
var amount32 [32]byte
copy(amount32[32-len(bigamount):32], bigamount)
input := append(contract.Bytes(), beneficiary.Bytes()...)
input = append(input, amount32[:]...)
return crypto.Keccak256(input)
}
// Balance returns the current balance of the chequebook.
func (self *Chequebook) Balance() *big.Int {
defer self.lock.Unlock()
self.lock.Lock()
return new(big.Int).Set(self.balance)
}
// Owner returns the owner account of the chequebook.
func (self *Chequebook) Owner() common.Address {
return self.owner
}
// Address returns the on-chain contract address of the chequebook.
func (self *Chequebook) Address() common.Address {
return self.contractAddr
}
// Deposit deposits money to the chequebook account.
func (self *Chequebook) Deposit(amount *big.Int) (string, error) {
defer self.lock.Unlock()
self.lock.Lock()
return self.deposit(amount)
}
// deposit deposits amount to the chequebook account.
// The caller must hold self.lock.
func (self *Chequebook) deposit(amount *big.Int) (string, error) {
// since the amount is variable here, we do not use sessions
depositTransactor := bind.NewKeyedTransactor(self.prvKey)
depositTransactor.Value = amount
chbookRaw := &contract.ChequebookRaw{Contract: self.contract}
tx, err := chbookRaw.Transfer(depositTransactor)
if err != nil {
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)
return "", err
}
// assume that transaction is actually successful, we add the amount to balance right away
self.balance.Add(self.balance, amount)
glog.V(logger.Detail).Infof("deposited %d wei to chequebook (%s, balance: %v, target: %v)", amount, self.contractAddr.Hex(), self.balance, self.buffer)
return tx.Hash().Hex(), nil
}
// AutoDeposit (re)sets interval time and amount which triggers sending funds to the
// chequebook. Contract backend needs to be set if threshold is not less than buffer, then
// deposit will be triggered on every new cheque issued.
func (self *Chequebook) AutoDeposit(interval time.Duration, threshold, buffer *big.Int) {
defer self.lock.Unlock()
self.lock.Lock()
self.threshold = threshold
self.buffer = buffer
self.autoDeposit(interval)
}
// autoDeposit starts a goroutine that periodically sends funds to the chequebook
// contract caller holds the lock the go routine terminates if Chequebook.quit is closed.
func (self *Chequebook) autoDeposit(interval time.Duration) {
if self.quit != nil {
close(self.quit)
self.quit = nil
}
// if threshold >= balance autodeposit after every cheque issued
if interval == time.Duration(0) || self.threshold != nil && self.buffer != nil && self.threshold.Cmp(self.buffer) >= 0 {
return
}
ticker := time.NewTicker(interval)
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.balance.Cmp(self.buffer) < 0 {
amount := new(big.Int).Sub(self.buffer, self.balance)
txhash, err := self.deposit(amount)
if err == nil {
self.txhash = txhash
}
}
self.lock.Unlock()
}
}
}()
return
}
// Outbox can issue cheques from a single contract to a single beneficiary.
type Outbox struct {
chequeBook *Chequebook
beneficiary common.Address
}
// NewOutbox creates an outbox.
func NewOutbox(chbook *Chequebook, beneficiary common.Address) *Outbox {
return &Outbox{chbook, beneficiary}
}
// Issue creates cheque.
func (self *Outbox) Issue(amount *big.Int) (interface{}, error) {
// TODO(fjl): the return type should be more descriptive.
return self.chequeBook.Issue(self.beneficiary, amount)
}
// AutoDeposit enables auto-deposits on the underlying chequebook.
func (self *Outbox) AutoDeposit(interval time.Duration, threshold, buffer *big.Int) {
self.chequeBook.AutoDeposit(interval, threshold, buffer)
}
// Stop helps satisfy the swap.OutPayment interface.
func (self *Outbox) Stop() {}
// String implements fmt.Stringer.
func (self *Outbox) String() string {
return fmt.Sprintf("chequebook: %v, beneficiary: %s, balance: %v", self.chequeBook.Address().Hex(), self.beneficiary.Hex(), self.chequeBook.Balance())
}
// Inbox can deposit, verify and cash cheques from a single contract to a single
// beneficiary. It is the incoming payment handler for peer to peer micropayments.
type Inbox struct {
lock sync.Mutex
contract common.Address // peer's chequebook contract
beneficiary common.Address // local peer's receiving address
sender common.Address // local peer's address to send cashing tx from
signer *ecdsa.PublicKey // peer's public key
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
maxUncashed *big.Int // threshold that triggers autocashing
cashed *big.Int // cumulative amount cashed
cheque *Cheque // last cheque, nil if none yet received
}
// 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
}

528
contracts/chequebook/cheque_test.go Normal file
View File

@ -0,0 +1,528 @@
// Copyright 2016 The go-ethereum Authors
// This file is part of the go-ethereum library.
//
// The go-ethereum library is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// The go-ethereum library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
package chequebook
import (
"crypto/ecdsa"
"math/big"
"os"
"path/filepath"
"testing"
"time"
"github.com/ethereum/go-ethereum/accounts/abi/bind"
"github.com/ethereum/go-ethereum/accounts/abi/bind/backends"
"github.com/ethereum/go-ethereum/common"
"github.com/ethereum/go-ethereum/contracts/chequebook/contract"
"github.com/ethereum/go-ethereum/core"
"github.com/ethereum/go-ethereum/crypto"
)
var (
key0, _ = crypto.HexToECDSA("b71c71a67e1177ad4e901695e1b4b9ee17ae16c6668d313eac2f96dbcda3f291")
key1, _ = crypto.HexToECDSA("8a1f9a8f95be41cd7ccb6168179afb4504aefe388d1e14474d32c45c72ce7b7a")
key2, _ = crypto.HexToECDSA("49a7b37aa6f6645917e7b807e9d1c00d4fa71f18343b0d4122a4d2df64dd6fee")
addr0 = crypto.PubkeyToAddress(key0.PublicKey)
addr1 = crypto.PubkeyToAddress(key1.PublicKey)
addr2 = crypto.PubkeyToAddress(key2.PublicKey)
)
func newTestBackend() *backends.SimulatedBackend {
return backends.NewSimulatedBackend(
core.GenesisAccount{Address: addr0, Balance: big.NewInt(1000000000)},
core.GenesisAccount{Address: addr1, Balance: big.NewInt(1000000000)},
core.GenesisAccount{Address: addr2, Balance: big.NewInt(1000000000)},
)
}
func deploy(prvKey *ecdsa.PrivateKey, amount *big.Int, backend *backends.SimulatedBackend) (common.Address, error) {
deployTransactor := bind.NewKeyedTransactor(prvKey)
deployTransactor.Value = amount
addr, _, _, err := contract.DeployChequebook(deployTransactor, backend)
if err != nil {
return common.Address{}, err
}
backend.Commit()
return addr, nil
}
func TestIssueAndReceive(t *testing.T) {
path := filepath.Join(os.TempDir(), "chequebook-test.json")
backend := newTestBackend()
addr0, err := deploy(key0, big.NewInt(0), backend)
if err != nil {
t.Fatalf("deploy contract: expected no error, got %v", err)
}
chbook, err := NewChequebook(path, addr0, key0, backend)
if err != nil {
t.Fatalf("expected no error, got %v", err)
}
chbook.sent[addr1] = new(big.Int).SetUint64(42)
amount := common.Big1
ch, err := chbook.Issue(addr1, amount)
if err == nil {
t.Fatalf("expected insufficient funds error, got none")
}
chbook.balance = new(big.Int).Set(common.Big1)
if chbook.Balance().Cmp(common.Big1) != 0 {
t.Fatalf("expected: %v, got %v", "0", chbook.Balance())
}
ch, err = chbook.Issue(addr1, amount)
if err != nil {
t.Fatalf("expected no error, got %v", err)
}
if chbook.Balance().Cmp(common.Big0) != 0 {
t.Errorf("expected: %v, got %v", "0", chbook.Balance())
}
chbox, err := NewInbox(key1, addr0, addr1, &key0.PublicKey, backend)
if err != nil {
t.Fatalf("expected no error, got %v", err)
}
received, err := chbox.Receive(ch)
if err != nil {
t.Fatalf("expected no error, got %v", err)
}
if received.Cmp(big.NewInt(43)) != 0 {
t.Errorf("expected: %v, got %v", "43", received)
}
}
func TestCheckbookFile(t *testing.T) {
path := filepath.Join(os.TempDir(), "chequebook-test.json")
backend := newTestBackend()
chbook, err := NewChequebook(path, addr0, key0, backend)
if err != nil {
t.Fatalf("expected no error, got %v", err)
}
chbook.sent[addr1] = new(big.Int).SetUint64(42)
chbook.balance = new(big.Int).Set(common.Big1)
chbook.Save()
chbook, err = LoadChequebook(path, key0, backend, false)
if err != nil {
t.Fatalf("expected no error, got %v", err)
}
if chbook.Balance().Cmp(common.Big1) != 0 {
t.Errorf("expected: %v, got %v", "0", chbook.Balance())
}
ch, err := chbook.Issue(addr1, common.Big1)
if err != nil {
t.Fatalf("expected no error, got %v", err)
}
if ch.Amount.Cmp(new(big.Int).SetUint64(43)) != 0 {
t.Errorf("expected: %v, got %v", "0", ch.Amount)
}
err = chbook.Save()
if err != nil {
t.Fatalf("expected no error, got %v", err)
}
}
func TestVerifyErrors(t *testing.T) {
path0 := filepath.Join(os.TempDir(), "chequebook-test-0.json")
backend := newTestBackend()
contr0, err := deploy(key0, common.Big2, backend)
if err != nil {
t.Errorf("expected no error, got %v", err)
}
chbook0, err := NewChequebook(path0, contr0, key0, backend)
if err != nil {
t.Errorf("expected no error, got %v", err)
}
path1 := filepath.Join(os.TempDir(), "chequebook-test-1.json")
contr1, err := deploy(key1, common.Big2, backend)
chbook1, err := NewChequebook(path1, contr1, key1, backend)
if err != nil {
t.Errorf("expected no error, got %v", err)
}
chbook0.sent[addr1] = new(big.Int).SetUint64(42)
chbook0.balance = new(big.Int).Set(common.Big2)
chbook1.balance = new(big.Int).Set(common.Big1)
amount := common.Big1
ch0, err := chbook0.Issue(addr1, amount)
if err != nil {
t.Fatalf("expected no error, got %v", err)
}
time.Sleep(5)
chbox, err := NewInbox(key1, contr0, addr1, &key0.PublicKey, backend)
if err != nil {
t.Fatalf("expected no error, got %v", err)
}
received, err := chbox.Receive(ch0)
if err != nil {
t.Fatalf("expected no error, got %v", err)
}
if received.Cmp(big.NewInt(43)) != 0 {
t.Errorf("expected: %v, got %v", "43", received)
}
ch1, err := chbook0.Issue(addr2, amount)
if err != nil {
t.Fatalf("expected no error, got %v", err)
}
received, err = chbox.Receive(ch1)
t.Logf("correct error: %v", err)
if err == nil {
t.Fatalf("expected receiver error, got none")
}
ch2, err := chbook1.Issue(addr1, amount)
if err != nil {
t.Fatalf("expected no error, got %v", err)
}
received, err = chbox.Receive(ch2)
t.Logf("correct error: %v", err)
if err == nil {
t.Fatalf("expected sender error, got none")
}
_, err = chbook1.Issue(addr1, new(big.Int).SetInt64(-1))
t.Logf("correct error: %v", err)
if err == nil {
t.Fatalf("expected incorrect amount error, got none")
}
received, err = chbox.Receive(ch0)
t.Logf("correct error: %v", err)
if err == nil {
t.Fatalf("expected incorrect amount error, got none")
}
}
func TestDeposit(t *testing.T) {
path0 := filepath.Join(os.TempDir(), "chequebook-test-0.json")
backend := newTestBackend()
contr0, err := deploy(key0, new(big.Int), backend)
chbook, err := NewChequebook(path0, contr0, key0, backend)
if err != nil {
t.Errorf("expected no error, got %v", err)
}
balance := new(big.Int).SetUint64(42)
chbook.Deposit(balance)
backend.Commit()
if chbook.balance.Cmp(balance) != 0 {
t.Fatalf("expected balance %v, got %v", balance, chbook.balance)
}
amount := common.Big1
_, err = chbook.Issue(addr1, amount)
if err != nil {
t.Fatalf("expected no error, got %v", err)
}
backend.Commit()
exp := new(big.Int).SetUint64(41)
if chbook.balance.Cmp(exp) != 0 {
t.Fatalf("expected balance %v, got %v", exp, chbook.balance)
}
// autodeposit on each issue
chbook.AutoDeposit(0, balance, balance)
_, err = chbook.Issue(addr1, amount)
if err != nil {
t.Fatalf("expected no error, got %v", err)
}
backend.Commit()
_, err = chbook.Issue(addr1, amount)
if err != nil {
t.Fatalf("expected no error, got %v", err)
}
backend.Commit()
if chbook.balance.Cmp(balance) != 0 {
t.Fatalf("expected balance %v, got %v", balance, chbook.balance)
}
// autodeposit off
chbook.AutoDeposit(0, common.Big0, balance)
_, err = chbook.Issue(addr1, amount)
if err != nil {
t.Fatalf("expected no error, got %v", err)
}
backend.Commit()
_, err = chbook.Issue(addr1, amount)
if err != nil {
t.Fatalf("expected no error, got %v", err)
}
backend.Commit()
exp = new(big.Int).SetUint64(40)
if chbook.balance.Cmp(exp) != 0 {
t.Fatalf("expected balance %v, got %v", exp, chbook.balance)
}
// autodeposit every 10ms if new cheque issued
interval := 30 * time.Millisecond
chbook.AutoDeposit(interval, common.Big1, balance)
_, err = chbook.Issue(addr1, amount)
if err != nil {
t.Fatalf("expected no error, got %v", err)
}
backend.Commit()
_, err = chbook.Issue(addr1, amount)
if err != nil {
t.Fatalf("expected no error, got %v", err)
}
backend.Commit()
exp = new(big.Int).SetUint64(38)
if chbook.balance.Cmp(exp) != 0 {
t.Fatalf("expected balance %v, got %v", exp, chbook.balance)
}
time.Sleep(3 * interval)
backend.Commit()
if chbook.balance.Cmp(balance) != 0 {
t.Fatalf("expected balance %v, got %v", balance, chbook.balance)
}
exp = new(big.Int).SetUint64(40)
chbook.AutoDeposit(4*interval, exp, balance)
_, err = chbook.Issue(addr1, amount)
if err != nil {
t.Fatalf("expected no error, got %v", err)
}
backend.Commit()
_, err = chbook.Issue(addr1, amount)
if err != nil {
t.Fatalf("expected no error, got %v", err)
}
time.Sleep(3 * interval)
backend.Commit()
if chbook.balance.Cmp(exp) != 0 {
t.Fatalf("expected balance %v, got %v", exp, chbook.balance)
}
_, err = chbook.Issue(addr1, amount)
if err != nil {
t.Fatalf("expected no error, got %v", err)
}
time.Sleep(1 * interval)
backend.Commit()
if chbook.balance.Cmp(balance) != 0 {
t.Fatalf("expected balance %v, got %v", balance, chbook.balance)
}
chbook.AutoDeposit(1*interval, common.Big0, balance)
chbook.Stop()
_, err = chbook.Issue(addr1, common.Big1)
if err != nil {
t.Fatalf("expected no error, got %v", err)
}
backend.Commit()
_, err = chbook.Issue(addr1, common.Big2)
if err != nil {
t.Fatalf("expected no error, got %v", err)
}
time.Sleep(1 * interval)
backend.Commit()
exp = new(big.Int).SetUint64(39)
if chbook.balance.Cmp(exp) != 0 {
t.Fatalf("expected balance %v, got %v", exp, chbook.balance)
}
}
func TestCash(t *testing.T) {
path := filepath.Join(os.TempDir(), "chequebook-test.json")
backend := newTestBackend()
contr0, err := deploy(key0, common.Big2, backend)
chbook, err := NewChequebook(path, contr0, key0, backend)
if err != nil {
t.Errorf("expected no error, got %v", err)
}
chbook.sent[addr1] = new(big.Int).SetUint64(42)
amount := common.Big1
chbook.balance = new(big.Int).Set(common.Big1)
ch, err := chbook.Issue(addr1, amount)
if err != nil {
t.Fatalf("expected no error, got %v", err)
}
backend.Commit()
chbox, err := NewInbox(key1, contr0, addr1, &key0.PublicKey, backend)
if err != nil {
t.Fatalf("expected no error, got %v", err)
}
// cashing latest cheque
_, err = chbox.Receive(ch)
if err != nil {
t.Fatalf("expected no error, got %v", err)
}
_, err = ch.Cash(chbook.session)
backend.Commit()
chbook.balance = new(big.Int).Set(common.Big3)
ch0, err := chbook.Issue(addr1, amount)
if err != nil {
t.Fatalf("expected no error, got %v", err)
}
backend.Commit()
ch1, err := chbook.Issue(addr1, amount)
if err != nil {
t.Fatalf("expected no error, got %v", err)
}
backend.Commit()
interval := 10 * time.Millisecond
// setting autocash with interval of 10ms
chbox.AutoCash(interval, nil)
_, err = chbox.Receive(ch0)
if err != nil {
t.Fatalf("expected no error, got %v", err)
}
_, err = chbox.Receive(ch1)
if err != nil {
t.Fatalf("expected no error, got %v", err)
}
backend.Commit()
// expBalance := big.NewInt(2)
// gotBalance := backend.BalanceAt(addr1)
// if gotBalance.Cmp(expBalance) != 0 {
// t.Fatalf("expected beneficiary balance %v, got %v", expBalance, gotBalance)
// }
// after 3x interval time and 2 cheques received, exactly one cashing tx is sent
time.Sleep(4 * interval)
backend.Commit()
// expBalance = big.NewInt(4)
// gotBalance = backend.BalanceAt(addr1)
// if gotBalance.Cmp(expBalance) != 0 {
// t.Fatalf("expected beneficiary balance %v, got %v", expBalance, gotBalance)
// }
// after stopping autocash no more tx are sent
ch2, err := chbook.Issue(addr1, amount)
if err != nil {
t.Fatalf("expected no error, got %v", err)
}
chbox.Stop()
_, err = chbox.Receive(ch2)
if err != nil {
t.Fatalf("expected no error, got %v", err)
}
time.Sleep(2 * interval)
backend.Commit()
// expBalance = big.NewInt(4)
// gotBalance = backend.BalanceAt(addr1)
// if gotBalance.Cmp(expBalance) != 0 {
// t.Fatalf("expected beneficiary balance %v, got %v", expBalance, gotBalance)
// }
// autocash below 1
chbook.balance = big.NewInt(2)
chbox.AutoCash(0, common.Big1)
ch3, err := chbook.Issue(addr1, amount)
if err != nil {
t.Fatalf("expected no error, got %v", err)
}
backend.Commit()
// expBalance = big.NewInt(4)
// gotBalance = backend.BalanceAt(addr1)
// if gotBalance.Cmp(expBalance) != 0 {
// t.Fatalf("expected beneficiary balance %v, got %v", expBalance, gotBalance)
// }
ch4, err := chbook.Issue(addr1, amount)
if err != nil {
t.Fatalf("expected no error, got %v", err)
}
backend.Commit()
_, err = chbox.Receive(ch3)
if err != nil {
t.Fatalf("expected no error, got %v", err)
}
backend.Commit()
_, err = chbox.Receive(ch4)
if err != nil {
t.Fatalf("expected no error, got %v", err)
}
backend.Commit()
// 2 checks of amount 1 received, exactly 1 tx is sent
// expBalance = big.NewInt(6)
// gotBalance = backend.BalanceAt(addr1)
// if gotBalance.Cmp(expBalance) != 0 {
// t.Fatalf("expected beneficiary balance %v, got %v", expBalance, gotBalance)
// }
// autochash on receipt when maxUncashed is 0
chbook.balance = new(big.Int).Set(common.Big2)
chbox.AutoCash(0, common.Big0)
ch5, err := chbook.Issue(addr1, amount)
if err != nil {
t.Fatalf("expected no error, got %v", err)
}
backend.Commit()
// expBalance = big.NewInt(5)
// gotBalance = backend.BalanceAt(addr1)
// if gotBalance.Cmp(expBalance) != 0 {
// t.Fatalf("expected beneficiary balance %v, got %v", expBalance, gotBalance)
// }
ch6, err := chbook.Issue(addr1, amount)
if err != nil {
t.Fatalf("expected no error, got %v", err)
}
_, err = chbox.Receive(ch5)
if err != nil {
t.Fatalf("expected no error, got %v", err)
}
backend.Commit()
// expBalance = big.NewInt(4)
// gotBalance = backend.BalanceAt(addr1)
// if gotBalance.Cmp(expBalance) != 0 {
// t.Fatalf("expected beneficiary balance %v, got %v", expBalance, gotBalance)
// }
_, err = chbox.Receive(ch6)
if err != nil {
t.Fatalf("expected no error, got %v", err)
}
backend.Commit()
// expBalance = big.NewInt(6)
// gotBalance = backend.BalanceAt(addr1)
// if gotBalance.Cmp(expBalance) != 0 {
// t.Fatalf("expected beneficiary balance %v, got %v", expBalance, gotBalance)
// }
}

554
contracts/chequebook/contract/chequebook.go Normal file
View File

@ -0,0 +1,554 @@
// Copyright 2016 The go-ethereum Authors
// This file is part of the go-ethereum library.
//
// The go-ethereum library is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// The go-ethereum library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
package contract
import (
"math/big"
"strings"
"github.com/ethereum/go-ethereum/accounts/abi"
"github.com/ethereum/go-ethereum/accounts/abi/bind"
"github.com/ethereum/go-ethereum/common"
"github.com/ethereum/go-ethereum/core/types"
)
// ChequebookABI is the input ABI used to generate the binding from.
const ChequebookABI = `[{"constant":false,"inputs":[],"name":"kill","outputs":[],"type":"function"},{"constant":true,"inputs":[{"name":"","type":"address"}],"name":"sent","outputs":[{"name":"","type":"uint256"}],"type":"function"},{"constant":false,"inputs":[{"name":"beneficiary","type":"address"},{"name":"amount","type":"uint256"},{"name":"sig_v","type":"uint8"},{"name":"sig_r","type":"bytes32"},{"name":"sig_s","type":"bytes32"}],"name":"cash","outputs":[],"type":"function"},{"anonymous":false,"inputs":[{"indexed":false,"name":"deadbeat","type":"address"}],"name":"Overdraft","type":"event"}]`
// ChequebookBin is the compiled bytecode used for deploying new contracts.
const ChequebookBin = `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`
// DeployChequebook deploys a new Ethereum contract, binding an instance of Chequebook to it.
func DeployChequebook(auth *bind.TransactOpts, backend bind.ContractBackend) (common.Address, *types.Transaction, *Chequebook, error) {
parsed, err := abi.JSON(strings.NewReader(ChequebookABI))
if err != nil {
return common.Address{}, nil, nil, err
}
address, tx, contract, err := bind.DeployContract(auth, parsed, common.FromHex(ChequebookBin), backend)
if err != nil {
return common.Address{}, nil, nil, err
}
return address, tx, &Chequebook{ChequebookCaller: ChequebookCaller{contract: contract}, ChequebookTransactor: ChequebookTransactor{contract: contract}}, nil
}
// Chequebook is an auto generated Go binding around an Ethereum contract.
type Chequebook struct {
ChequebookCaller // Read-only binding to the contract
ChequebookTransactor // Write-only binding to the contract
}
// ChequebookCaller is an auto generated read-only Go binding around an Ethereum contract.
type ChequebookCaller struct {
contract *bind.BoundContract // Generic contract wrapper for the low level calls
}
// ChequebookTransactor is an auto generated write-only Go binding around an Ethereum contract.
type ChequebookTransactor struct {
contract *bind.BoundContract // Generic contract wrapper for the low level calls
}
// ChequebookSession is an auto generated Go binding around an Ethereum contract,
// with pre-set call and transact options.
type ChequebookSession struct {
Contract *Chequebook // Generic contract binding to set the session for
CallOpts bind.CallOpts // Call options to use throughout this session
TransactOpts bind.TransactOpts // Transaction auth options to use throughout this session
}
// ChequebookCallerSession is an auto generated read-only Go binding around an Ethereum contract,
// with pre-set call options.
type ChequebookCallerSession struct {
Contract *ChequebookCaller // Generic contract caller binding to set the session for
CallOpts bind.CallOpts // Call options to use throughout this session
}
// ChequebookTransactorSession is an auto generated write-only Go binding around an Ethereum contract,
// with pre-set transact options.
type ChequebookTransactorSession struct {
Contract *ChequebookTransactor // Generic contract transactor binding to set the session for
TransactOpts bind.TransactOpts // Transaction auth options to use throughout this session
}
// ChequebookRaw is an auto generated low-level Go binding around an Ethereum contract.
type ChequebookRaw struct {
Contract *Chequebook // Generic contract binding to access the raw methods on
}
// ChequebookCallerRaw is an auto generated low-level read-only Go binding around an Ethereum contract.
type ChequebookCallerRaw struct {
Contract *ChequebookCaller // Generic read-only contract binding to access the raw methods on
}
// ChequebookTransactorRaw is an auto generated low-level write-only Go binding around an Ethereum contract.
type ChequebookTransactorRaw struct {
Contract *ChequebookTransactor // Generic write-only contract binding to access the raw methods on
}
// NewChequebook creates a new instance of Chequebook, bound to a specific deployed contract.
func NewChequebook(address common.Address, backend bind.ContractBackend) (*Chequebook, error) {
contract, err := bindChequebook(address, backend, backend)
if err != nil {
return nil, err
}
return &Chequebook{ChequebookCaller: ChequebookCaller{contract: contract}, ChequebookTransactor: ChequebookTransactor{contract: contract}}, nil
}
// NewChequebookCaller creates a new read-only instance of Chequebook, bound to a specific deployed contract.
func NewChequebookCaller(address common.Address, caller bind.ContractCaller) (*ChequebookCaller, error) {
contract, err := bindChequebook(address, caller, nil)
if err != nil {
return nil, err
}
return &ChequebookCaller{contract: contract}, nil
}
// NewChequebookTransactor creates a new write-only instance of Chequebook, bound to a specific deployed contract.
func NewChequebookTransactor(address common.Address, transactor bind.ContractTransactor) (*ChequebookTransactor, error) {
contract, err := bindChequebook(address, nil, transactor)
if err != nil {
return nil, err
}
return &ChequebookTransactor{contract: contract}, nil
}
// bindChequebook binds a generic wrapper to an already deployed contract.
func bindChequebook(address common.Address, caller bind.ContractCaller, transactor bind.ContractTransactor) (*bind.BoundContract, error) {
parsed, err := abi.JSON(strings.NewReader(ChequebookABI))
if err != nil {
return nil, err
}
return bind.NewBoundContract(address, parsed, caller, transactor), nil
}
// Call invokes the (constant) contract method with params as input values and
// sets the output to result. The result type might be a single field for simple
// returns, a slice of interfaces for anonymous returns and a struct for named
// returns.
func (_Chequebook *ChequebookRaw) Call(opts *bind.CallOpts, result interface{}, method string, params ...interface{}) error {
return _Chequebook.Contract.ChequebookCaller.contract.Call(opts, result, method, params...)
}
// Transfer initiates a plain transaction to move funds to the contract, calling
// its default method if one is available.
func (_Chequebook *ChequebookRaw) Transfer(opts *bind.TransactOpts) (*types.Transaction, error) {
return _Chequebook.Contract.ChequebookTransactor.contract.Transfer(opts)
}
// Transact invokes the (paid) contract method with params as input values.
func (_Chequebook *ChequebookRaw) Transact(opts *bind.TransactOpts, method string, params ...interface{}) (*types.Transaction, error) {
return _Chequebook.Contract.ChequebookTransactor.contract.Transact(opts, method, params...)
}
// Call invokes the (constant) contract method with params as input values and
// sets the output to result. The result type might be a single field for simple
// returns, a slice of interfaces for anonymous returns and a struct for named
// returns.
func (_Chequebook *ChequebookCallerRaw) Call(opts *bind.CallOpts, result interface{}, method string, params ...interface{}) error {
return _Chequebook.Contract.contract.Call(opts, result, method, params...)
}
// Transfer initiates a plain transaction to move funds to the contract, calling
// its default method if one is available.
func (_Chequebook *ChequebookTransactorRaw) Transfer(opts *bind.TransactOpts) (*types.Transaction, error) {
return _Chequebook.Contract.contract.Transfer(opts)
}
// Transact invokes the (paid) contract method with params as input values.
func (_Chequebook *ChequebookTransactorRaw) Transact(opts *bind.TransactOpts, method string, params ...interface{}) (*types.Transaction, error) {
return _Chequebook.Contract.contract.Transact(opts, method, params...)
}
// Sent is a free data retrieval call binding the contract method 0x7bf786f8.
//
// Solidity: function sent( address) constant returns(uint256)
func (_Chequebook *ChequebookCaller) Sent(opts *bind.CallOpts, arg0 common.Address) (*big.Int, error) {
var (
ret0 = new(*big.Int)
)
out := ret0
err := _Chequebook.contract.Call(opts, out, "sent", arg0)
return *ret0, err
}
// Sent is a free data retrieval call binding the contract method 0x7bf786f8.
//
// Solidity: function sent( address) constant returns(uint256)
func (_Chequebook *ChequebookSession) Sent(arg0 common.Address) (*big.Int, error) {
return _Chequebook.Contract.Sent(&_Chequebook.CallOpts, arg0)
}
// Sent is a free data retrieval call binding the contract method 0x7bf786f8.
//
// Solidity: function sent( address) constant returns(uint256)
func (_Chequebook *ChequebookCallerSession) Sent(arg0 common.Address) (*big.Int, error) {
return _Chequebook.Contract.Sent(&_Chequebook.CallOpts, arg0)
}
// Cash is a paid mutator transaction binding the contract method 0xfbf788d6.
//
// Solidity: function cash(beneficiary address, amount uint256, sig_v uint8, sig_r bytes32, sig_s bytes32) returns()
func (_Chequebook *ChequebookTransactor) Cash(opts *bind.TransactOpts, beneficiary common.Address, amount *big.Int, sig_v uint8, sig_r [32]byte, sig_s [32]byte) (*types.Transaction, error) {
return _Chequebook.contract.Transact(opts, "cash", beneficiary, amount, sig_v, sig_r, sig_s)
}
// Cash is a paid mutator transaction binding the contract method 0xfbf788d6.
//
// Solidity: function cash(beneficiary address, amount uint256, sig_v uint8, sig_r bytes32, sig_s bytes32) returns()
func (_Chequebook *ChequebookSession) Cash(beneficiary common.Address, amount *big.Int, sig_v uint8, sig_r [32]byte, sig_s [32]byte) (*types.Transaction, error) {
return _Chequebook.Contract.Cash(&_Chequebook.TransactOpts, beneficiary, amount, sig_v, sig_r, sig_s)
}
// Cash is a paid mutator transaction binding the contract method 0xfbf788d6.
//
// Solidity: function cash(beneficiary address, amount uint256, sig_v uint8, sig_r bytes32, sig_s bytes32) returns()
func (_Chequebook *ChequebookTransactorSession) Cash(beneficiary common.Address, amount *big.Int, sig_v uint8, sig_r [32]byte, sig_s [32]byte) (*types.Transaction, error) {
return _Chequebook.Contract.Cash(&_Chequebook.TransactOpts, beneficiary, amount, sig_v, sig_r, sig_s)
}
// Kill is a paid mutator transaction binding the contract method 0x41c0e1b5.
//
// Solidity: function kill() returns()
func (_Chequebook *ChequebookTransactor) Kill(opts *bind.TransactOpts) (*types.Transaction, error) {
return _Chequebook.contract.Transact(opts, "kill")
}
// Kill is a paid mutator transaction binding the contract method 0x41c0e1b5.
//
// Solidity: function kill() returns()
func (_Chequebook *ChequebookSession) Kill() (*types.Transaction, error) {
return _Chequebook.Contract.Kill(&_Chequebook.TransactOpts)
}
// Kill is a paid mutator transaction binding the contract method 0x41c0e1b5.
//
// Solidity: function kill() returns()
func (_Chequebook *ChequebookTransactorSession) Kill() (*types.Transaction, error) {
return _Chequebook.Contract.Kill(&_Chequebook.TransactOpts)
}
// MortalABI is the input ABI used to generate the binding from.
const MortalABI = `[{"constant":false,"inputs":[],"name":"kill","outputs":[],"type":"function"}]`
// MortalBin is the compiled bytecode used for deploying new contracts.
const MortalBin = `0x606060405260008054600160a060020a03191633179055605c8060226000396000f3606060405260e060020a600035046341c0e1b58114601a575b005b60186000543373ffffffffffffffffffffffffffffffffffffffff90811691161415605a5760005473ffffffffffffffffffffffffffffffffffffffff16ff5b56`
// DeployMortal deploys a new Ethereum contract, binding an instance of Mortal to it.
func DeployMortal(auth *bind.TransactOpts, backend bind.ContractBackend) (common.Address, *types.Transaction, *Mortal, error) {
parsed, err := abi.JSON(strings.NewReader(MortalABI))
if err != nil {
return common.Address{}, nil, nil, err
}
address, tx, contract, err := bind.DeployContract(auth, parsed, common.FromHex(MortalBin), backend)
if err != nil {
return common.Address{}, nil, nil, err
}
return address, tx, &Mortal{MortalCaller: MortalCaller{contract: contract}, MortalTransactor: MortalTransactor{contract: contract}}, nil
}
// Mortal is an auto generated Go binding around an Ethereum contract.
type Mortal struct {
MortalCaller // Read-only binding to the contract
MortalTransactor // Write-only binding to the contract
}
// MortalCaller is an auto generated read-only Go binding around an Ethereum contract.
type MortalCaller struct {
contract *bind.BoundContract // Generic contract wrapper for the low level calls
}
// MortalTransactor is an auto generated write-only Go binding around an Ethereum contract.
type MortalTransactor struct {
contract *bind.BoundContract // Generic contract wrapper for the low level calls
}
// MortalSession is an auto generated Go binding around an Ethereum contract,
// with pre-set call and transact options.
type MortalSession struct {
Contract *Mortal // Generic contract binding to set the session for
CallOpts bind.CallOpts // Call options to use throughout this session
TransactOpts bind.TransactOpts // Transaction auth options to use throughout this session
}
// MortalCallerSession is an auto generated read-only Go binding around an Ethereum contract,
// with pre-set call options.
type MortalCallerSession struct {
Contract *MortalCaller // Generic contract caller binding to set the session for
CallOpts bind.CallOpts // Call options to use throughout this session
}
// MortalTransactorSession is an auto generated write-only Go binding around an Ethereum contract,
// with pre-set transact options.
type MortalTransactorSession struct {
Contract *MortalTransactor // Generic contract transactor binding to set the session for
TransactOpts bind.TransactOpts // Transaction auth options to use throughout this session
}
// MortalRaw is an auto generated low-level Go binding around an Ethereum contract.
type MortalRaw struct {
Contract *Mortal // Generic contract binding to access the raw methods on
}
// MortalCallerRaw is an auto generated low-level read-only Go binding around an Ethereum contract.
type MortalCallerRaw struct {
Contract *MortalCaller // Generic read-only contract binding to access the raw methods on
}
// MortalTransactorRaw is an auto generated low-level write-only Go binding around an Ethereum contract.
type MortalTransactorRaw struct {
Contract *MortalTransactor // Generic write-only contract binding to access the raw methods on
}
// NewMortal creates a new instance of Mortal, bound to a specific deployed contract.
func NewMortal(address common.Address, backend bind.ContractBackend) (*Mortal, error) {
contract, err := bindMortal(address, backend, backend)
if err != nil {
return nil, err
}
return &Mortal{MortalCaller: MortalCaller{contract: contract}, MortalTransactor: MortalTransactor{contract: contract}}, nil
}
// NewMortalCaller creates a new read-only instance of Mortal, bound to a specific deployed contract.
func NewMortalCaller(address common.Address, caller bind.ContractCaller) (*MortalCaller, error) {
contract, err := bindMortal(address, caller, nil)
if err != nil {
return nil, err
}
return &MortalCaller{contract: contract}, nil
}
// NewMortalTransactor creates a new write-only instance of Mortal, bound to a specific deployed contract.
func NewMortalTransactor(address common.Address, transactor bind.ContractTransactor) (*MortalTransactor, error) {
contract, err := bindMortal(address, nil, transactor)
if err != nil {
return nil, err
}
return &MortalTransactor{contract: contract}, nil
}
// bindMortal binds a generic wrapper to an already deployed contract.
func bindMortal(address common.Address, caller bind.ContractCaller, transactor bind.ContractTransactor) (*bind.BoundContract, error) {
parsed, err := abi.JSON(strings.NewReader(MortalABI))
if err != nil {
return nil, err
}
return bind.NewBoundContract(address, parsed, caller, transactor), nil
}
// Call invokes the (constant) contract method with params as input values and
// sets the output to result. The result type might be a single field for simple
// returns, a slice of interfaces for anonymous returns and a struct for named
// returns.
func (_Mortal *MortalRaw) Call(opts *bind.CallOpts, result interface{}, method string, params ...interface{}) error {
return _Mortal.Contract.MortalCaller.contract.Call(opts, result, method, params...)
}
// Transfer initiates a plain transaction to move funds to the contract, calling
// its default method if one is available.
func (_Mortal *MortalRaw) Transfer(opts *bind.TransactOpts) (*types.Transaction, error) {
return _Mortal.Contract.MortalTransactor.contract.Transfer(opts)
}
// Transact invokes the (paid) contract method with params as input values.
func (_Mortal *MortalRaw) Transact(opts *bind.TransactOpts, method string, params ...interface{}) (*types.Transaction, error) {
return _Mortal.Contract.MortalTransactor.contract.Transact(opts, method, params...)
}
// Call invokes the (constant) contract method with params as input values and
// sets the output to result. The result type might be a single field for simple
// returns, a slice of interfaces for anonymous returns and a struct for named
// returns.
func (_Mortal *MortalCallerRaw) Call(opts *bind.CallOpts, result interface{}, method string, params ...interface{}) error {
return _Mortal.Contract.contract.Call(opts, result, method, params...)
}
// Transfer initiates a plain transaction to move funds to the contract, calling
// its default method if one is available.
func (_Mortal *MortalTransactorRaw) Transfer(opts *bind.TransactOpts) (*types.Transaction, error) {
return _Mortal.Contract.contract.Transfer(opts)
}
// Transact invokes the (paid) contract method with params as input values.
func (_Mortal *MortalTransactorRaw) Transact(opts *bind.TransactOpts, method string, params ...interface{}) (*types.Transaction, error) {
return _Mortal.Contract.contract.Transact(opts, method, params...)
}
// Kill is a paid mutator transaction binding the contract method 0x41c0e1b5.
//
// Solidity: function kill() returns()
func (_Mortal *MortalTransactor) Kill(opts *bind.TransactOpts) (*types.Transaction, error) {
return _Mortal.contract.Transact(opts, "kill")
}
// Kill is a paid mutator transaction binding the contract method 0x41c0e1b5.
//
// Solidity: function kill() returns()
func (_Mortal *MortalSession) Kill() (*types.Transaction, error) {
return _Mortal.Contract.Kill(&_Mortal.TransactOpts)
}
// Kill is a paid mutator transaction binding the contract method 0x41c0e1b5.
//
// Solidity: function kill() returns()
func (_Mortal *MortalTransactorSession) Kill() (*types.Transaction, error) {
return _Mortal.Contract.Kill(&_Mortal.TransactOpts)
}
// OwnedABI is the input ABI used to generate the binding from.
const OwnedABI = `[{"inputs":[],"type":"constructor"}]`
// OwnedBin is the compiled bytecode used for deploying new contracts.
const OwnedBin = `0x606060405260008054600160a060020a0319163317905560068060226000396000f3606060405200`
// DeployOwned deploys a new Ethereum contract, binding an instance of Owned to it.
func DeployOwned(auth *bind.TransactOpts, backend bind.ContractBackend) (common.Address, *types.Transaction, *Owned, error) {
parsed, err := abi.JSON(strings.NewReader(OwnedABI))
if err != nil {
return common.Address{}, nil, nil, err
}
address, tx, contract, err := bind.DeployContract(auth, parsed, common.FromHex(OwnedBin), backend)
if err != nil {
return common.Address{}, nil, nil, err
}
return address, tx, &Owned{OwnedCaller: OwnedCaller{contract: contract}, OwnedTransactor: OwnedTransactor{contract: contract}}, nil
}
// Owned is an auto generated Go binding around an Ethereum contract.
type Owned struct {
OwnedCaller // Read-only binding to the contract
OwnedTransactor // Write-only binding to the contract
}
// OwnedCaller is an auto generated read-only Go binding around an Ethereum contract.
type OwnedCaller struct {
contract *bind.BoundContract // Generic contract wrapper for the low level calls
}
// OwnedTransactor is an auto generated write-only Go binding around an Ethereum contract.
type OwnedTransactor struct {
contract *bind.BoundContract // Generic contract wrapper for the low level calls
}
// OwnedSession is an auto generated Go binding around an Ethereum contract,
// with pre-set call and transact options.
type OwnedSession struct {
Contract *Owned // Generic contract binding to set the session for
CallOpts bind.CallOpts // Call options to use throughout this session
TransactOpts bind.TransactOpts // Transaction auth options to use throughout this session
}
// OwnedCallerSession is an auto generated read-only Go binding around an Ethereum contract,
// with pre-set call options.
type OwnedCallerSession struct {
Contract *OwnedCaller // Generic contract caller binding to set the session for
CallOpts bind.CallOpts // Call options to use throughout this session
}
// OwnedTransactorSession is an auto generated write-only Go binding around an Ethereum contract,
// with pre-set transact options.
type OwnedTransactorSession struct {
Contract *OwnedTransactor // Generic contract transactor binding to set the session for
TransactOpts bind.TransactOpts // Transaction auth options to use throughout this session
}
// OwnedRaw is an auto generated low-level Go binding around an Ethereum contract.
type OwnedRaw struct {
Contract *Owned // Generic contract binding to access the raw methods on
}
// OwnedCallerRaw is an auto generated low-level read-only Go binding around an Ethereum contract.
type OwnedCallerRaw struct {
Contract *OwnedCaller // Generic read-only contract binding to access the raw methods on
}
// OwnedTransactorRaw is an auto generated low-level write-only Go binding around an Ethereum contract.
type OwnedTransactorRaw struct {
Contract *OwnedTransactor // Generic write-only contract binding to access the raw methods on
}
// NewOwned creates a new instance of Owned, bound to a specific deployed contract.
func NewOwned(address common.Address, backend bind.ContractBackend) (*Owned, error) {
contract, err := bindOwned(address, backend, backend)
if err != nil {
return nil, err
}
return &Owned{OwnedCaller: OwnedCaller{contract: contract}, OwnedTransactor: OwnedTransactor{contract: contract}}, nil
}
// NewOwnedCaller creates a new read-only instance of Owned, bound to a specific deployed contract.
func NewOwnedCaller(address common.Address, caller bind.ContractCaller) (*OwnedCaller, error) {
contract, err := bindOwned(address, caller, nil)
if err != nil {
return nil, err
}
return &OwnedCaller{contract: contract}, nil
}
// NewOwnedTransactor creates a new write-only instance of Owned, bound to a specific deployed contract.
func NewOwnedTransactor(address common.Address, transactor bind.ContractTransactor) (*OwnedTransactor, error) {
contract, err := bindOwned(address, nil, transactor)
if err != nil {
return nil, err
}
return &OwnedTransactor{contract: contract}, nil
}
// bindOwned binds a generic wrapper to an already deployed contract.
func bindOwned(address common.Address, caller bind.ContractCaller, transactor bind.ContractTransactor) (*bind.BoundContract, error) {
parsed, err := abi.JSON(strings.NewReader(OwnedABI))
if err != nil {
return nil, err
}
return bind.NewBoundContract(address, parsed, caller, transactor), nil
}
// Call invokes the (constant) contract method with params as input values and
// sets the output to result. The result type might be a single field for simple
// returns, a slice of interfaces for anonymous returns and a struct for named
// returns.
func (_Owned *OwnedRaw) Call(opts *bind.CallOpts, result interface{}, method string, params ...interface{}) error {
return _Owned.Contract.OwnedCaller.contract.Call(opts, result, method, params...)
}
// Transfer initiates a plain transaction to move funds to the contract, calling
// its default method if one is available.
func (_Owned *OwnedRaw) Transfer(opts *bind.TransactOpts) (*types.Transaction, error) {
return _Owned.Contract.OwnedTransactor.contract.Transfer(opts)
}
// Transact invokes the (paid) contract method with params as input values.
func (_Owned *OwnedRaw) Transact(opts *bind.TransactOpts, method string, params ...interface{}) (*types.Transaction, error) {
return _Owned.Contract.OwnedTransactor.contract.Transact(opts, method, params...)
}
// Call invokes the (constant) contract method with params as input values and
// sets the output to result. The result type might be a single field for simple
// returns, a slice of interfaces for anonymous returns and a struct for named
// returns.
func (_Owned *OwnedCallerRaw) Call(opts *bind.CallOpts, result interface{}, method string, params ...interface{}) error {
return _Owned.Contract.contract.Call(opts, result, method, params...)
}
// Transfer initiates a plain transaction to move funds to the contract, calling
// its default method if one is available.
func (_Owned *OwnedTransactorRaw) Transfer(opts *bind.TransactOpts) (*types.Transaction, error) {
return _Owned.Contract.contract.Transfer(opts)
}
// Transact invokes the (paid) contract method with params as input values.
func (_Owned *OwnedTransactorRaw) Transact(opts *bind.TransactOpts, method string, params ...interface{}) (*types.Transaction, error) {
return _Owned.Contract.contract.Transact(opts, method, params...)
}

43
contracts/chequebook/contract/chequebook.sol Normal file
View File

@ -0,0 +1,43 @@
import "mortal";
/// @title Chequebook for Ethereum micropayments
/// @author Daniel A. Nagy <daniel@ethdev.com>
contract chequebook is mortal {
// Cumulative paid amount in wei to each beneficiary
mapping (address => uint256) public sent;
/// @notice Overdraft event
event Overdraft(address deadbeat);
/// @notice Cash cheque
///
/// @param beneficiary beneficiary address
/// @param amount cumulative amount in wei
/// @param sig_v signature parameter v
/// @param sig_r signature parameter r
/// @param sig_s signature parameter s
/// The digital signature is calculated on the concatenated triplet of contract address, beneficiary address and cumulative amount
function cash(address beneficiary, uint256 amount,
uint8 sig_v, bytes32 sig_r, bytes32 sig_s) {
// Check if the cheque is old.
// Only cheques that are more recent than the last cashed one are considered.
if(amount <= sent[beneficiary]) return;
// Check the digital signature of the cheque.
bytes32 hash = sha3(address(this), beneficiary, amount);
if(owner != ecrecover(hash, sig_v, sig_r, sig_s)) return;
// Attempt sending the difference between the cumulative amount on the cheque
// and the cumulative amount on the last cashed cheque to beneficiary.
if (amount - sent[beneficiary] >= this.balance) {
if (beneficiary.send(amount - sent[beneficiary])) {
// Upon success, update the cumulative amount.
sent[beneficiary] = amount;
}
} else {
// Upon failure, punish owner for writing a bounced cheque.
// owner.sendToDebtorsPrison();
Overdraft(owner);
// Compensate beneficiary.
suicide(beneficiary);
}
}
}

21
contracts/chequebook/contract/code.go Normal file
View File

@ -0,0 +1,21 @@
// Copyright 2016 The go-ethereum Authors
// This file is part of the go-ethereum library.
//
// The go-ethereum library is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// The go-ethereum library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
package contract
// ContractDeployedCode is used to detect suicides. This constant needs to be
// updated when the contract code is changed.
const ContractDeployedCode = "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"

73
contracts/chequebook/gencode.go Normal file
View File

@ -0,0 +1,73 @@
// Copyright 2016 The go-ethereum Authors
// This file is part of the go-ethereum library.
//
// The go-ethereum library is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// The go-ethereum library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
// +build none
// This program generates contract/code.go, which contains the chequebook code
// after deployment.
package main
import (
"fmt"
"io/ioutil"
"math/big"
"github.com/ethereum/go-ethereum/accounts/abi/bind"
"github.com/ethereum/go-ethereum/accounts/abi/bind/backends"
"github.com/ethereum/go-ethereum/contracts/chequebook/contract"
"github.com/ethereum/go-ethereum/core"
"github.com/ethereum/go-ethereum/crypto"
)
var (
testKey, _ = crypto.HexToECDSA("b71c71a67e1177ad4e901695e1b4b9ee17ae16c6668d313eac2f96dbcda3f291")
testAccount = core.GenesisAccount{
Address: crypto.PubkeyToAddress(testKey.PublicKey),
Balance: big.NewInt(500000000000),
}
)
func main() {
backend := backends.NewSimulatedBackend(testAccount)
auth := bind.NewKeyedTransactor(testKey)
// Deploy the contract, get the code.
addr, _, _, err := contract.DeployChequebook(auth, backend)
if err != nil {
panic(err)
}
backend.Commit()
code, err := backend.CodeAt(nil, addr, nil)
if err != nil {
panic(err)
}
if len(code) == 0 {
panic("empty code")
}
// Write the output file.
content := fmt.Sprintf(`// TODO: insert license header
package contract
// ContractDeployedCode is used to detect suicides. This constant needs to be
// updated when the contract code is changed.
const ContractDeployedCode = "%#x"
`, code)
if err := ioutil.WriteFile("contract/code.go", []byte(content), 0644); err != nil {
panic(err)
}
}