plugeth/accounts/abi/bind/base.go
Marius van der Wijden ed0670cb17
accounts/abi/bind: allow specifying signer on transactOpts ()
This commit enables users to specify which signer they want to use while creating their transactOpts.
Previously all contract interactions used the homestead signer. Now a user can specify whether they
want to sign with homestead or EIP155 and specify the chainID which adds another layer of security.

Closes 
2020-12-08 14:44:56 +01:00

389 lines
14 KiB
Go

// Copyright 2015 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 bind
import (
"context"
"errors"
"fmt"
"math/big"
"github.com/ethereum/go-ethereum"
"github.com/ethereum/go-ethereum/accounts/abi"
"github.com/ethereum/go-ethereum/common"
"github.com/ethereum/go-ethereum/core/types"
"github.com/ethereum/go-ethereum/crypto"
"github.com/ethereum/go-ethereum/event"
)
// SignerFn is a signer function callback when a contract requires a method to
// sign the transaction before submission.
type SignerFn func(common.Address, *types.Transaction) (*types.Transaction, error)
// CallOpts is the collection of options to fine tune a contract call request.
type CallOpts struct {
Pending bool // Whether to operate on the pending state or the last known one
From common.Address // Optional the sender address, otherwise the first account is used
BlockNumber *big.Int // Optional the block number on which the call should be performed
Context context.Context // Network context to support cancellation and timeouts (nil = no timeout)
}
// TransactOpts is the collection of authorization data required to create a
// valid Ethereum transaction.
type TransactOpts struct {
From common.Address // Ethereum account to send the transaction from
Nonce *big.Int // Nonce to use for the transaction execution (nil = use pending state)
Signer SignerFn // Method to use for signing the transaction (mandatory)
Value *big.Int // Funds to transfer along the transaction (nil = 0 = no funds)
GasPrice *big.Int // Gas price to use for the transaction execution (nil = gas price oracle)
GasLimit uint64 // Gas limit to set for the transaction execution (0 = estimate)
Context context.Context // Network context to support cancellation and timeouts (nil = no timeout)
}
// FilterOpts is the collection of options to fine tune filtering for events
// within a bound contract.
type FilterOpts struct {
Start uint64 // Start of the queried range
End *uint64 // End of the range (nil = latest)
Context context.Context // Network context to support cancellation and timeouts (nil = no timeout)
}
// WatchOpts is the collection of options to fine tune subscribing for events
// within a bound contract.
type WatchOpts struct {
Start *uint64 // Start of the queried range (nil = latest)
Context context.Context // Network context to support cancellation and timeouts (nil = no timeout)
}
// BoundContract is the base wrapper object that reflects a contract on the
// Ethereum network. It contains a collection of methods that are used by the
// higher level contract bindings to operate.
type BoundContract struct {
address common.Address // Deployment address of the contract on the Ethereum blockchain
abi abi.ABI // Reflect based ABI to access the correct Ethereum methods
caller ContractCaller // Read interface to interact with the blockchain
transactor ContractTransactor // Write interface to interact with the blockchain
filterer ContractFilterer // Event filtering to interact with the blockchain
}
// NewBoundContract creates a low level contract interface through which calls
// and transactions may be made through.
func NewBoundContract(address common.Address, abi abi.ABI, caller ContractCaller, transactor ContractTransactor, filterer ContractFilterer) *BoundContract {
return &BoundContract{
address: address,
abi: abi,
caller: caller,
transactor: transactor,
filterer: filterer,
}
}
// DeployContract deploys a contract onto the Ethereum blockchain and binds the
// deployment address with a Go wrapper.
func DeployContract(opts *TransactOpts, abi abi.ABI, bytecode []byte, backend ContractBackend, params ...interface{}) (common.Address, *types.Transaction, *BoundContract, error) {
// Otherwise try to deploy the contract
c := NewBoundContract(common.Address{}, abi, backend, backend, backend)
input, err := c.abi.Pack("", params...)
if err != nil {
return common.Address{}, nil, nil, err
}
tx, err := c.transact(opts, nil, append(bytecode, input...))
if err != nil {
return common.Address{}, nil, nil, err
}
c.address = crypto.CreateAddress(opts.From, tx.Nonce())
return c.address, tx, c, 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 (c *BoundContract) Call(opts *CallOpts, results *[]interface{}, method string, params ...interface{}) error {
// Don't crash on a lazy user
if opts == nil {
opts = new(CallOpts)
}
if results == nil {
results = new([]interface{})
}
// Pack the input, call and unpack the results
input, err := c.abi.Pack(method, params...)
if err != nil {
return err
}
var (
msg = ethereum.CallMsg{From: opts.From, To: &c.address, Data: input}
ctx = ensureContext(opts.Context)
code []byte
output []byte
)
if opts.Pending {
pb, ok := c.caller.(PendingContractCaller)
if !ok {
return ErrNoPendingState
}
output, err = pb.PendingCallContract(ctx, msg)
if err == nil && len(output) == 0 {
// Make sure we have a contract to operate on, and bail out otherwise.
if code, err = pb.PendingCodeAt(ctx, c.address); err != nil {
return err
} else if len(code) == 0 {
return ErrNoCode
}
}
} else {
output, err = c.caller.CallContract(ctx, msg, opts.BlockNumber)
if err != nil {
return err
}
if len(output) == 0 {
// Make sure we have a contract to operate on, and bail out otherwise.
if code, err = c.caller.CodeAt(ctx, c.address, opts.BlockNumber); err != nil {
return err
} else if len(code) == 0 {
return ErrNoCode
}
}
}
if len(*results) == 0 {
res, err := c.abi.Unpack(method, output)
*results = res
return err
}
res := *results
return c.abi.UnpackIntoInterface(res[0], method, output)
}
// Transact invokes the (paid) contract method with params as input values.
func (c *BoundContract) Transact(opts *TransactOpts, method string, params ...interface{}) (*types.Transaction, error) {
// Otherwise pack up the parameters and invoke the contract
input, err := c.abi.Pack(method, params...)
if err != nil {
return nil, err
}
// todo(rjl493456442) check the method is payable or not,
// reject invalid transaction at the first place
return c.transact(opts, &c.address, input)
}
// RawTransact initiates a transaction with the given raw calldata as the input.
// It's usually used to initiate transactions for invoking **Fallback** function.
func (c *BoundContract) RawTransact(opts *TransactOpts, calldata []byte) (*types.Transaction, error) {
// todo(rjl493456442) check the method is payable or not,
// reject invalid transaction at the first place
return c.transact(opts, &c.address, calldata)
}
// Transfer initiates a plain transaction to move funds to the contract, calling
// its default method if one is available.
func (c *BoundContract) Transfer(opts *TransactOpts) (*types.Transaction, error) {
// todo(rjl493456442) check the payable fallback or receive is defined
// or not, reject invalid transaction at the first place
return c.transact(opts, &c.address, nil)
}
// transact executes an actual transaction invocation, first deriving any missing
// authorization fields, and then scheduling the transaction for execution.
func (c *BoundContract) transact(opts *TransactOpts, contract *common.Address, input []byte) (*types.Transaction, error) {
var err error
// Ensure a valid value field and resolve the account nonce
value := opts.Value
if value == nil {
value = new(big.Int)
}
var nonce uint64
if opts.Nonce == nil {
nonce, err = c.transactor.PendingNonceAt(ensureContext(opts.Context), opts.From)
if err != nil {
return nil, fmt.Errorf("failed to retrieve account nonce: %v", err)
}
} else {
nonce = opts.Nonce.Uint64()
}
// Figure out the gas allowance and gas price values
gasPrice := opts.GasPrice
if gasPrice == nil {
gasPrice, err = c.transactor.SuggestGasPrice(ensureContext(opts.Context))
if err != nil {
return nil, fmt.Errorf("failed to suggest gas price: %v", err)
}
}
gasLimit := opts.GasLimit
if gasLimit == 0 {
// Gas estimation cannot succeed without code for method invocations
if contract != nil {
if code, err := c.transactor.PendingCodeAt(ensureContext(opts.Context), c.address); err != nil {
return nil, err
} else if len(code) == 0 {
return nil, ErrNoCode
}
}
// If the contract surely has code (or code is not needed), estimate the transaction
msg := ethereum.CallMsg{From: opts.From, To: contract, GasPrice: gasPrice, Value: value, Data: input}
gasLimit, err = c.transactor.EstimateGas(ensureContext(opts.Context), msg)
if err != nil {
return nil, fmt.Errorf("failed to estimate gas needed: %v", err)
}
}
// Create the transaction, sign it and schedule it for execution
var rawTx *types.Transaction
if contract == nil {
rawTx = types.NewContractCreation(nonce, value, gasLimit, gasPrice, input)
} else {
rawTx = types.NewTransaction(nonce, c.address, value, gasLimit, gasPrice, input)
}
if opts.Signer == nil {
return nil, errors.New("no signer to authorize the transaction with")
}
signedTx, err := opts.Signer(opts.From, rawTx)
if err != nil {
return nil, err
}
if err := c.transactor.SendTransaction(ensureContext(opts.Context), signedTx); err != nil {
return nil, err
}
return signedTx, nil
}
// FilterLogs filters contract logs for past blocks, returning the necessary
// channels to construct a strongly typed bound iterator on top of them.
func (c *BoundContract) FilterLogs(opts *FilterOpts, name string, query ...[]interface{}) (chan types.Log, event.Subscription, error) {
// Don't crash on a lazy user
if opts == nil {
opts = new(FilterOpts)
}
// Append the event selector to the query parameters and construct the topic set
query = append([][]interface{}{{c.abi.Events[name].ID}}, query...)
topics, err := abi.MakeTopics(query...)
if err != nil {
return nil, nil, err
}
// Start the background filtering
logs := make(chan types.Log, 128)
config := ethereum.FilterQuery{
Addresses: []common.Address{c.address},
Topics: topics,
FromBlock: new(big.Int).SetUint64(opts.Start),
}
if opts.End != nil {
config.ToBlock = new(big.Int).SetUint64(*opts.End)
}
/* TODO(karalabe): Replace the rest of the method below with this when supported
sub, err := c.filterer.SubscribeFilterLogs(ensureContext(opts.Context), config, logs)
*/
buff, err := c.filterer.FilterLogs(ensureContext(opts.Context), config)
if err != nil {
return nil, nil, err
}
sub, err := event.NewSubscription(func(quit <-chan struct{}) error {
for _, log := range buff {
select {
case logs <- log:
case <-quit:
return nil
}
}
return nil
}), nil
if err != nil {
return nil, nil, err
}
return logs, sub, nil
}
// WatchLogs filters subscribes to contract logs for future blocks, returning a
// subscription object that can be used to tear down the watcher.
func (c *BoundContract) WatchLogs(opts *WatchOpts, name string, query ...[]interface{}) (chan types.Log, event.Subscription, error) {
// Don't crash on a lazy user
if opts == nil {
opts = new(WatchOpts)
}
// Append the event selector to the query parameters and construct the topic set
query = append([][]interface{}{{c.abi.Events[name].ID}}, query...)
topics, err := abi.MakeTopics(query...)
if err != nil {
return nil, nil, err
}
// Start the background filtering
logs := make(chan types.Log, 128)
config := ethereum.FilterQuery{
Addresses: []common.Address{c.address},
Topics: topics,
}
if opts.Start != nil {
config.FromBlock = new(big.Int).SetUint64(*opts.Start)
}
sub, err := c.filterer.SubscribeFilterLogs(ensureContext(opts.Context), config, logs)
if err != nil {
return nil, nil, err
}
return logs, sub, nil
}
// UnpackLog unpacks a retrieved log into the provided output structure.
func (c *BoundContract) UnpackLog(out interface{}, event string, log types.Log) error {
if len(log.Data) > 0 {
if err := c.abi.UnpackIntoInterface(out, event, log.Data); err != nil {
return err
}
}
var indexed abi.Arguments
for _, arg := range c.abi.Events[event].Inputs {
if arg.Indexed {
indexed = append(indexed, arg)
}
}
return abi.ParseTopics(out, indexed, log.Topics[1:])
}
// UnpackLogIntoMap unpacks a retrieved log into the provided map.
func (c *BoundContract) UnpackLogIntoMap(out map[string]interface{}, event string, log types.Log) error {
if len(log.Data) > 0 {
if err := c.abi.UnpackIntoMap(out, event, log.Data); err != nil {
return err
}
}
var indexed abi.Arguments
for _, arg := range c.abi.Events[event].Inputs {
if arg.Indexed {
indexed = append(indexed, arg)
}
}
return abi.ParseTopicsIntoMap(out, indexed, log.Topics[1:])
}
// ensureContext is a helper method to ensure a context is not nil, even if the
// user specified it as such.
func ensureContext(ctx context.Context) context.Context {
if ctx == nil {
return context.TODO()
}
return ctx
}