// 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 . package backends import ( "context" "errors" "fmt" "math/big" "sync" "time" "github.com/ethereum/go-ethereum" "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/common/hexutil" "github.com/ethereum/go-ethereum/common/math" "github.com/ethereum/go-ethereum/consensus/ethash" "github.com/ethereum/go-ethereum/core" "github.com/ethereum/go-ethereum/core/bloombits" "github.com/ethereum/go-ethereum/core/mps" "github.com/ethereum/go-ethereum/core/rawdb" "github.com/ethereum/go-ethereum/core/state" "github.com/ethereum/go-ethereum/core/types" "github.com/ethereum/go-ethereum/core/vm" "github.com/ethereum/go-ethereum/eth" "github.com/ethereum/go-ethereum/eth/filters" "github.com/ethereum/go-ethereum/ethdb" "github.com/ethereum/go-ethereum/event" "github.com/ethereum/go-ethereum/log" "github.com/ethereum/go-ethereum/params" "github.com/ethereum/go-ethereum/rpc" ) // This nil assignment ensures at compile time that SimulatedBackend implements bind.ContractBackend. var _ bind.ContractBackend = (*SimulatedBackend)(nil) var ( errBlockNumberUnsupported = errors.New("simulatedBackend cannot access blocks other than the latest block") errBlockDoesNotExist = errors.New("block does not exist in blockchain") errTransactionDoesNotExist = errors.New("transaction does not exist") ) // SimulatedBackend implements bind.ContractBackend, simulating a blockchain in // the background. Its main purpose is to allow for easy testing of contract bindings. // Simulated backend implements the following interfaces: // ChainReader, ChainStateReader, ContractBackend, ContractCaller, ContractFilterer, ContractTransactor, // DeployBackend, GasEstimator, GasPricer, LogFilterer, PendingContractCaller, TransactionReader, and TransactionSender type SimulatedBackend struct { database ethdb.Database // In memory database to store our testing data blockchain *core.BlockChain // Ethereum blockchain to handle the consensus mu sync.Mutex pendingBlock *types.Block // Currently pending block that will be imported on request pendingState *state.StateDB // Currently pending state that will be the active on request events *filters.EventSystem // Event system for filtering log events live config *params.ChainConfig } // NewSimulatedBackendWithDatabase creates a new binding backend based on the given database // and uses a simulated blockchain for testing purposes. // A simulated backend always uses chainID 1337. func NewSimulatedBackendWithDatabase(database ethdb.Database, alloc core.GenesisAlloc, gasLimit uint64) *SimulatedBackend { genesis := core.Genesis{Config: params.AllEthashProtocolChanges, GasLimit: gasLimit, Alloc: alloc} genesis.MustCommit(database) blockchain, _ := core.NewBlockChain(database, nil, genesis.Config, ethash.NewFaker(), vm.Config{}, nil, nil, nil) backend := &SimulatedBackend{ database: database, blockchain: blockchain, config: genesis.Config, events: filters.NewEventSystem(&filterBackend{database, blockchain}, false), } backend.rollback() return backend } // Quorum // // Create a simulated backend based on existing Ethereum service func NewSimulatedBackendFrom(ethereum *eth.Ethereum) *SimulatedBackend { backend := &SimulatedBackend{ database: ethereum.ChainDb(), blockchain: ethereum.BlockChain(), config: ethereum.BlockChain().Config(), events: filters.NewEventSystem(&filterBackend{ethereum.ChainDb(), ethereum.BlockChain()}, false), } backend.rollback() return backend } // NewSimulatedBackend creates a new binding backend using a simulated blockchain // for testing purposes. // A simulated backend always uses chainID 1337. func NewSimulatedBackend(alloc core.GenesisAlloc, gasLimit uint64) *SimulatedBackend { return NewSimulatedBackendWithDatabase(rawdb.NewMemoryDatabase(), alloc, gasLimit) } // Close terminates the underlying blockchain's update loop. func (b *SimulatedBackend) Close() error { b.blockchain.Stop() return nil } // Commit imports all the pending transactions as a single block and starts a // fresh new state. func (b *SimulatedBackend) Commit() { b.mu.Lock() defer b.mu.Unlock() if _, err := b.blockchain.InsertChain([]*types.Block{b.pendingBlock}); err != nil { panic(err) // This cannot happen unless the simulator is wrong, fail in that case } b.rollback() } // Rollback aborts all pending transactions, reverting to the last committed state. func (b *SimulatedBackend) Rollback() { b.mu.Lock() defer b.mu.Unlock() b.rollback() } func (b *SimulatedBackend) rollback() { blocks, _ := core.GenerateChain(b.config, b.blockchain.CurrentBlock(), ethash.NewFaker(), b.database, 1, func(int, *core.BlockGen) {}) b.pendingBlock = blocks[0] b.pendingState, _ = state.New(b.pendingBlock.Root(), b.blockchain.StateCache(), nil) } // stateByBlockNumber retrieves a state by a given blocknumber. func (b *SimulatedBackend) stateByBlockNumber(ctx context.Context, blockNumber *big.Int) (*state.StateDB, error) { if blockNumber == nil || blockNumber.Cmp(b.blockchain.CurrentBlock().Number()) == 0 { statedb, _, err := b.blockchain.State() return statedb, err } block, err := b.blockByNumberNoLock(ctx, blockNumber) if err != nil { return nil, err } statedb, _, err := b.blockchain.StateAt(block.Root()) return statedb, err } // CodeAt returns the code associated with a certain account in the blockchain. func (b *SimulatedBackend) CodeAt(ctx context.Context, contract common.Address, blockNumber *big.Int) ([]byte, error) { b.mu.Lock() defer b.mu.Unlock() stateDB, err := b.stateByBlockNumber(ctx, blockNumber) if err != nil { return nil, err } stateDB, _, _ = b.blockchain.State() return stateDB.GetCode(contract), nil } // BalanceAt returns the wei balance of a certain account in the blockchain. func (b *SimulatedBackend) BalanceAt(ctx context.Context, contract common.Address, blockNumber *big.Int) (*big.Int, error) { b.mu.Lock() defer b.mu.Unlock() stateDB, err := b.stateByBlockNumber(ctx, blockNumber) if err != nil { return nil, err } stateDB, _, _ = b.blockchain.State() return stateDB.GetBalance(contract), nil } // NonceAt returns the nonce of a certain account in the blockchain. func (b *SimulatedBackend) NonceAt(ctx context.Context, contract common.Address, blockNumber *big.Int) (uint64, error) { b.mu.Lock() defer b.mu.Unlock() stateDB, err := b.stateByBlockNumber(ctx, blockNumber) if err != nil { return 0, err } stateDB, _, _ = b.blockchain.State() return stateDB.GetNonce(contract), nil } // StorageAt returns the value of key in the storage of an account in the blockchain. func (b *SimulatedBackend) StorageAt(ctx context.Context, contract common.Address, key common.Hash, blockNumber *big.Int) ([]byte, error) { b.mu.Lock() defer b.mu.Unlock() stateDB, err := b.stateByBlockNumber(ctx, blockNumber) if err != nil { return nil, err } stateDB, _, _ = b.blockchain.State() val := stateDB.GetState(contract, key) return val[:], nil } // TransactionReceipt returns the receipt of a transaction. func (b *SimulatedBackend) TransactionReceipt(ctx context.Context, txHash common.Hash) (*types.Receipt, error) { b.mu.Lock() defer b.mu.Unlock() receipt, _, _, _ := rawdb.ReadReceipt(b.database, txHash, b.config) return receipt, nil } // TransactionByHash checks the pool of pending transactions in addition to the // blockchain. The isPending return value indicates whether the transaction has been // mined yet. Note that the transaction may not be part of the canonical chain even if // it's not pending. func (b *SimulatedBackend) TransactionByHash(ctx context.Context, txHash common.Hash) (*types.Transaction, bool, error) { b.mu.Lock() defer b.mu.Unlock() tx := b.pendingBlock.Transaction(txHash) if tx != nil { return tx, true, nil } tx, _, _, _ = rawdb.ReadTransaction(b.database, txHash) if tx != nil { return tx, false, nil } return nil, false, ethereum.NotFound } // BlockByHash retrieves a block based on the block hash. func (b *SimulatedBackend) BlockByHash(ctx context.Context, hash common.Hash) (*types.Block, error) { b.mu.Lock() defer b.mu.Unlock() if hash == b.pendingBlock.Hash() { return b.pendingBlock, nil } block := b.blockchain.GetBlockByHash(hash) if block != nil { return block, nil } return nil, errBlockDoesNotExist } // BlockByNumber retrieves a block from the database by number, caching it // (associated with its hash) if found. func (b *SimulatedBackend) BlockByNumber(ctx context.Context, number *big.Int) (*types.Block, error) { b.mu.Lock() defer b.mu.Unlock() return b.blockByNumberNoLock(ctx, number) } // blockByNumberNoLock retrieves a block from the database by number, caching it // (associated with its hash) if found without Lock. func (b *SimulatedBackend) blockByNumberNoLock(ctx context.Context, number *big.Int) (*types.Block, error) { if number == nil || number.Cmp(b.pendingBlock.Number()) == 0 { return b.blockchain.CurrentBlock(), nil } block := b.blockchain.GetBlockByNumber(uint64(number.Int64())) if block == nil { return nil, errBlockDoesNotExist } return block, nil } // HeaderByHash returns a block header from the current canonical chain. func (b *SimulatedBackend) HeaderByHash(ctx context.Context, hash common.Hash) (*types.Header, error) { b.mu.Lock() defer b.mu.Unlock() if hash == b.pendingBlock.Hash() { return b.pendingBlock.Header(), nil } header := b.blockchain.GetHeaderByHash(hash) if header == nil { return nil, errBlockDoesNotExist } return header, nil } // HeaderByNumber returns a block header from the current canonical chain. If number is // nil, the latest known header is returned. func (b *SimulatedBackend) HeaderByNumber(ctx context.Context, block *big.Int) (*types.Header, error) { b.mu.Lock() defer b.mu.Unlock() if block == nil || block.Cmp(b.pendingBlock.Number()) == 0 { return b.blockchain.CurrentHeader(), nil } return b.blockchain.GetHeaderByNumber(uint64(block.Int64())), nil } // TransactionCount returns the number of transactions in a given block. func (b *SimulatedBackend) TransactionCount(ctx context.Context, blockHash common.Hash) (uint, error) { b.mu.Lock() defer b.mu.Unlock() if blockHash == b.pendingBlock.Hash() { return uint(b.pendingBlock.Transactions().Len()), nil } block := b.blockchain.GetBlockByHash(blockHash) if block == nil { return uint(0), errBlockDoesNotExist } return uint(block.Transactions().Len()), nil } // TransactionInBlock returns the transaction for a specific block at a specific index. func (b *SimulatedBackend) TransactionInBlock(ctx context.Context, blockHash common.Hash, index uint) (*types.Transaction, error) { b.mu.Lock() defer b.mu.Unlock() if blockHash == b.pendingBlock.Hash() { transactions := b.pendingBlock.Transactions() if uint(len(transactions)) < index+1 { return nil, errTransactionDoesNotExist } return transactions[index], nil } block := b.blockchain.GetBlockByHash(blockHash) if block == nil { return nil, errBlockDoesNotExist } transactions := block.Transactions() if uint(len(transactions)) < index+1 { return nil, errTransactionDoesNotExist } return transactions[index], nil } // PendingCodeAt returns the code associated with an account in the pending state. func (b *SimulatedBackend) PendingCodeAt(ctx context.Context, contract common.Address) ([]byte, error) { b.mu.Lock() defer b.mu.Unlock() return b.pendingState.GetCode(contract), nil } func newRevertError(result *core.ExecutionResult) *revertError { reason, errUnpack := abi.UnpackRevert(result.Revert()) err := errors.New("execution reverted") if errUnpack == nil { err = fmt.Errorf("execution reverted: %v", reason) } return &revertError{ error: err, reason: hexutil.Encode(result.Revert()), } } // revertError is an API error that encompasses an EVM revert with JSON error // code and a binary data blob. type revertError struct { error reason string // revert reason hex encoded } // ErrorCode returns the JSON error code for a revert. // See: https://github.com/ethereum/wiki/wiki/JSON-RPC-Error-Codes-Improvement-Proposal func (e *revertError) ErrorCode() int { return 3 } // ErrorData returns the hex encoded revert reason. func (e *revertError) ErrorData() interface{} { return e.reason } // CallContract executes a contract call. func (b *SimulatedBackend) CallContract(ctx context.Context, call ethereum.CallMsg, blockNumber *big.Int) ([]byte, error) { b.mu.Lock() defer b.mu.Unlock() if blockNumber != nil && blockNumber.Cmp(b.blockchain.CurrentBlock().Number()) != 0 { return nil, errBlockNumberUnsupported } stateDB, _, err := b.blockchain.State() if err != nil { return nil, err } res, err := b.callContract(ctx, call, b.blockchain.CurrentBlock(), stateDB, stateDB) if err != nil { return nil, err } // If the result contains a revert reason, try to unpack and return it. if len(res.Revert()) > 0 { return nil, newRevertError(res) } return res.Return(), res.Err } // PendingCallContract executes a contract call on the pending state. func (b *SimulatedBackend) PendingCallContract(ctx context.Context, call ethereum.CallMsg) ([]byte, error) { b.mu.Lock() defer b.mu.Unlock() defer b.pendingState.RevertToSnapshot(b.pendingState.Snapshot()) res, err := b.callContract(ctx, call, b.pendingBlock, b.pendingState, b.pendingState) if err != nil { return nil, err } // If the result contains a revert reason, try to unpack and return it. if len(res.Revert()) > 0 { return nil, newRevertError(res) } return res.Return(), res.Err } // PendingNonceAt implements PendingStateReader.PendingNonceAt, retrieving // the nonce currently pending for the account. func (b *SimulatedBackend) PendingNonceAt(ctx context.Context, account common.Address) (uint64, error) { b.mu.Lock() defer b.mu.Unlock() return b.pendingState.GetOrNewStateObject(account).Nonce(), nil } // SuggestGasPrice implements ContractTransactor.SuggestGasPrice. Since the simulated // chain doesn't have miners, we just return a gas price of 1 for any call. func (b *SimulatedBackend) SuggestGasPrice(ctx context.Context) (*big.Int, error) { return big.NewInt(1), nil } // EstimateGas executes the requested code against the currently pending block/state and // returns the used amount of gas. func (b *SimulatedBackend) EstimateGas(ctx context.Context, call ethereum.CallMsg) (uint64, error) { b.mu.Lock() defer b.mu.Unlock() // Determine the lowest and highest possible gas limits to binary search in between var ( lo uint64 = params.TxGas - 1 hi uint64 cap uint64 ) if call.Gas >= params.TxGas { hi = call.Gas } else { hi = b.pendingBlock.GasLimit() } // Recap the highest gas allowance with account's balance. if call.GasPrice != nil && call.GasPrice.BitLen() != 0 { balance := b.pendingState.GetBalance(call.From) // from can't be nil available := new(big.Int).Set(balance) if call.Value != nil { if call.Value.Cmp(available) >= 0 { return 0, errors.New("insufficient funds for transfer") } available.Sub(available, call.Value) } allowance := new(big.Int).Div(available, call.GasPrice) if allowance.IsUint64() && hi > allowance.Uint64() { transfer := call.Value if transfer == nil { transfer = new(big.Int) } log.Warn("Gas estimation capped by limited funds", "original", hi, "balance", balance, "sent", transfer, "gasprice", call.GasPrice, "fundable", allowance) hi = allowance.Uint64() } } cap = hi // Create a helper to check if a gas allowance results in an executable transaction executable := func(gas uint64) (bool, *core.ExecutionResult, error) { call.Gas = gas snapshot := b.pendingState.Snapshot() res, err := b.callContract(ctx, call, b.pendingBlock, b.pendingState, b.pendingState) b.pendingState.RevertToSnapshot(snapshot) if err != nil { if errors.Is(err, core.ErrIntrinsicGas) { return true, nil, nil // Special case, raise gas limit } return true, nil, err // Bail out } return res.Failed(), res, nil } // Execute the binary search and hone in on an executable gas limit for lo+1 < hi { mid := (hi + lo) / 2 failed, _, err := executable(mid) // If the error is not nil(consensus error), it means the provided message // call or transaction will never be accepted no matter how much gas it is // assigned. Return the error directly, don't struggle any more if err != nil { return 0, err } if failed { lo = mid } else { hi = mid } } // Reject the transaction as invalid if it still fails at the highest allowance if hi == cap { failed, result, err := executable(hi) if err != nil { return 0, err } if failed { if result != nil && result.Err != vm.ErrOutOfGas { if len(result.Revert()) > 0 { return 0, newRevertError(result) } return 0, result.Err } // Otherwise, the specified gas cap is too low return 0, fmt.Errorf("gas required exceeds allowance (%d)", cap) } } return hi, nil } // callContract implements common code between normal and pending contract calls. // state is modified during execution, make sure to copy it if necessary. func (b *SimulatedBackend) callContract(ctx context.Context, call ethereum.CallMsg, block *types.Block, stateDB *state.StateDB, privateState *state.StateDB) (*core.ExecutionResult, error) { // Ensure message is initialized properly. if call.GasPrice == nil { call.GasPrice = big.NewInt(1) } if call.Gas == 0 { call.Gas = 50000000 } if call.Value == nil { call.Value = new(big.Int) } // Set infinite balance to the fake caller account. from := stateDB.GetOrNewStateObject(call.From) from.SetBalance(math.MaxBig256) // Execute the call. msg := callMsg{call} txContext := core.NewEVMTxContext(msg) evmContext := core.NewEVMBlockContext(block.Header(), b.blockchain, nil) // Create a new environment which holds all relevant information // about the transaction and calling mechanisms. vmEnv := vm.NewEVM(evmContext, txContext, stateDB, privateState, b.config, vm.Config{}) gasPool := new(core.GasPool).AddGas(math.MaxUint64) return core.NewStateTransition(vmEnv, msg, gasPool).TransitionDb() } // SendTransaction updates the pending block to include the given transaction. // It panics if the transaction is invalid. func (b *SimulatedBackend) SendTransaction(ctx context.Context, tx *types.Transaction, args bind.PrivateTxArgs) error { b.mu.Lock() defer b.mu.Unlock() // Check transaction validity. block := b.blockchain.CurrentBlock() signer := types.MakeSigner(b.blockchain.Config(), block.Number()) sender, err := types.Sender(signer, tx) if err != nil { panic(fmt.Errorf("invalid transaction: %v", err)) } nonce := b.pendingState.GetNonce(sender) if tx.Nonce() != nonce { panic(fmt.Errorf("invalid transaction nonce: got %d, want %d", tx.Nonce(), nonce)) } // Include tx in chain. blocks, _ := core.GenerateChain(b.config, block, ethash.NewFaker(), b.database, 1, func(number int, block *core.BlockGen) { for _, tx := range b.pendingBlock.Transactions() { block.AddTxWithChain(b.blockchain, tx) } block.AddTxWithChain(b.blockchain, tx) }) stateDB, _, _ := b.blockchain.State() b.pendingBlock = blocks[0] b.pendingState, _ = state.New(b.pendingBlock.Root(), stateDB.Database(), nil) return nil } // PreparePrivateTransaction dummy implementation func (b *SimulatedBackend) PreparePrivateTransaction(data []byte, privateFrom string) (common.EncryptedPayloadHash, error) { return common.EncryptedPayloadHash{}, nil } func (b *SimulatedBackend) DistributeTransaction(ctx context.Context, tx *types.Transaction, args bind.PrivateTxArgs) (string, error) { return tx.Hash().String(), nil } // FilterLogs executes a log filter operation, blocking during execution and // returning all the results in one batch. // // TODO(karalabe): Deprecate when the subscription one can return past data too. func (b *SimulatedBackend) FilterLogs(ctx context.Context, query ethereum.FilterQuery) ([]types.Log, error) { var filter *filters.Filter if query.BlockHash != nil { // Block filter requested, construct a single-shot filter filter = filters.NewBlockFilter(&filterBackend{b.database, b.blockchain}, *query.BlockHash, query.Addresses, query.Topics, query.PSI) } else { // Initialize unset filter boundaries to run from genesis to chain head from := int64(0) if query.FromBlock != nil { from = query.FromBlock.Int64() } to := int64(-1) if query.ToBlock != nil { to = query.ToBlock.Int64() } // Construct the range filter filter = filters.NewRangeFilter(&filterBackend{b.database, b.blockchain}, from, to, query.Addresses, query.Topics, query.PSI) } // Run the filter and return all the logs logs, err := filter.Logs(ctx) if err != nil { return nil, err } res := make([]types.Log, len(logs)) for i, nLog := range logs { res[i] = *nLog } return res, nil } // SubscribeFilterLogs creates a background log filtering operation, returning a // subscription immediately, which can be used to stream the found events. func (b *SimulatedBackend) SubscribeFilterLogs(ctx context.Context, query ethereum.FilterQuery, ch chan<- types.Log) (ethereum.Subscription, error) { // Subscribe to contract events sink := make(chan []*types.Log) sub, err := b.events.SubscribeLogs(query, sink) if err != nil { return nil, err } // Since we're getting logs in batches, we need to flatten them into a plain stream return event.NewSubscription(func(quit <-chan struct{}) error { defer sub.Unsubscribe() for { select { case logs := <-sink: for _, nlog := range logs { select { case ch <- *nlog: case err := <-sub.Err(): return err case <-quit: return nil } } case err := <-sub.Err(): return err case <-quit: return nil } } }), nil } // SubscribeNewHead returns an event subscription for a new header. func (b *SimulatedBackend) SubscribeNewHead(ctx context.Context, ch chan<- *types.Header) (ethereum.Subscription, error) { // subscribe to a new head sink := make(chan *types.Header) sub := b.events.SubscribeNewHeads(sink) return event.NewSubscription(func(quit <-chan struct{}) error { defer sub.Unsubscribe() for { select { case head := <-sink: select { case ch <- head: case err := <-sub.Err(): return err case <-quit: return nil } case err := <-sub.Err(): return err case <-quit: return nil } } }), nil } // AdjustTime adds a time shift to the simulated clock. // It can only be called on empty blocks. func (b *SimulatedBackend) AdjustTime(adjustment time.Duration) error { b.mu.Lock() defer b.mu.Unlock() if len(b.pendingBlock.Transactions()) != 0 { return errors.New("Could not adjust time on non-empty block") } blocks, _ := core.GenerateChain(b.config, b.blockchain.CurrentBlock(), ethash.NewFaker(), b.database, 1, func(number int, block *core.BlockGen) { block.OffsetTime(int64(adjustment.Seconds())) }) stateDB, _, _ := b.blockchain.State() b.pendingBlock = blocks[0] b.pendingState, _ = state.New(b.pendingBlock.Root(), stateDB.Database(), nil) return nil } // Blockchain returns the underlying blockchain. func (b *SimulatedBackend) Blockchain() *core.BlockChain { return b.blockchain } // callMsg implements core.Message to allow passing it as a transaction simulator. type callMsg struct { ethereum.CallMsg } func (m callMsg) From() common.Address { return m.CallMsg.From } func (m callMsg) Nonce() uint64 { return 0 } func (m callMsg) CheckNonce() bool { return false } func (m callMsg) To() *common.Address { return m.CallMsg.To } func (m callMsg) GasPrice() *big.Int { return m.CallMsg.GasPrice } func (m callMsg) Gas() uint64 { return m.CallMsg.Gas } func (m callMsg) Value() *big.Int { return m.CallMsg.Value } func (m callMsg) Data() []byte { return m.CallMsg.Data } func (m callMsg) AccessList() types.AccessList { return m.CallMsg.AccessList } // filterBackend implements filters.Backend to support filtering for logs without // taking bloom-bits acceleration structures into account. type filterBackend struct { db ethdb.Database bc *core.BlockChain } func (fb *filterBackend) ChainDb() ethdb.Database { return fb.db } func (fb *filterBackend) EventMux() *event.TypeMux { panic("not supported") } func (fb *filterBackend) PSMR() mps.PrivateStateMetadataResolver { return fb.bc.PrivateStateManager() } func (fb *filterBackend) HeaderByNumber(ctx context.Context, block rpc.BlockNumber) (*types.Header, error) { if block == rpc.LatestBlockNumber { return fb.bc.CurrentHeader(), nil } return fb.bc.GetHeaderByNumber(uint64(block.Int64())), nil } func (fb *filterBackend) HeaderByHash(ctx context.Context, hash common.Hash) (*types.Header, error) { return fb.bc.GetHeaderByHash(hash), nil } func (fb *filterBackend) GetReceipts(ctx context.Context, hash common.Hash) (types.Receipts, error) { number := rawdb.ReadHeaderNumber(fb.db, hash) if number == nil { return nil, nil } return rawdb.ReadReceipts(fb.db, hash, *number, fb.bc.Config()), nil } func (fb *filterBackend) GetLogs(ctx context.Context, hash common.Hash) ([][]*types.Log, error) { number := rawdb.ReadHeaderNumber(fb.db, hash) if number == nil { return nil, nil } receipts := rawdb.ReadReceipts(fb.db, hash, *number, fb.bc.Config()) if receipts == nil { return nil, nil } logs := make([][]*types.Log, len(receipts)) for i, receipt := range receipts { logs[i] = receipt.Logs } return logs, nil } func (fb *filterBackend) SubscribeNewTxsEvent(ch chan<- core.NewTxsEvent) event.Subscription { return nullSubscription() } func (fb *filterBackend) SubscribeChainEvent(ch chan<- core.ChainEvent) event.Subscription { return fb.bc.SubscribeChainEvent(ch) } func (fb *filterBackend) SubscribeRemovedLogsEvent(ch chan<- core.RemovedLogsEvent) event.Subscription { return fb.bc.SubscribeRemovedLogsEvent(ch) } func (fb *filterBackend) SubscribeLogsEvent(ch chan<- []*types.Log) event.Subscription { return fb.bc.SubscribeLogsEvent(ch) } func (fb *filterBackend) SubscribePendingLogsEvent(ch chan<- []*types.Log) event.Subscription { return nullSubscription() } func (fb *filterBackend) BloomStatus() (uint64, uint64) { return 4096, 0 } func (fb *filterBackend) ServiceFilter(ctx context.Context, ms *bloombits.MatcherSession) { panic("not supported") } func (fb *filterBackend) AccountExtraDataStateGetterByNumber(context.Context, rpc.BlockNumber) (vm.AccountExtraDataStateGetter, error) { panic("not supported") } func nullSubscription() event.Subscription { return event.NewSubscription(func(quit <-chan struct{}) error { <-quit return nil }) }