eth, internal: implements contract backend

eth/bind.go

@@ -0,0 +1,181 @@
+// Copyright 2018 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 eth
+
+import (
+	"context"
+	"math/big"
+
+	"github.com/ethereum/go-ethereum"
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/common/hexutil"
+	"github.com/ethereum/go-ethereum/core/types"
+	"github.com/ethereum/go-ethereum/eth/filters"
+	"github.com/ethereum/go-ethereum/event"
+	"github.com/ethereum/go-ethereum/internal/ethapi"
+	"github.com/ethereum/go-ethereum/rlp"
+	"github.com/ethereum/go-ethereum/rpc"
+)
+
+// ContractBackend implements bind.ContractBackend with direct calls to Ethereum
+// internals to support operating on contracts within subprotocols like eth, les and
+// swarm.
+//
+// Internally this backend uses the already exposed API endpoints of the Ethereum
+// object. These should be rewritten to internal Go method calls when the Go API
+// is refactored to support a clean library use.
+type ContractBackend struct {
+	eapi      *ethapi.PublicEthereumAPI        // Wrapper around the Ethereum object to access metadata
+	bcapi     *ethapi.PublicBlockChainAPI      // Wrapper around the blockchain to access chain data
+	txapi     *ethapi.PublicTransactionPoolAPI // Wrapper around the transaction pool to access transaction data
+	filterapi *filters.PublicFilterAPI         // Wrapper around the filter to watch and retrieve contract logs
+}
+
+// NewContractBackend creates a new native contract backend using an existing
+// Ethereum object.
+func NewContractBackend(apiBackend ethapi.Backend, lightMode bool) *ContractBackend {
+	return &ContractBackend{
+		eapi:      ethapi.NewPublicEthereumAPI(apiBackend),
+		bcapi:     ethapi.NewPublicBlockChainAPI(apiBackend),
+		txapi:     ethapi.NewPublicTransactionPoolAPI(apiBackend, new(ethapi.AddrLocker)),
+		filterapi: filters.NewPublicFilterAPI(apiBackend.(filters.Backend), lightMode),
+	}
+}
+
+// CodeAt implements bind.ContractCaller retrieving any code associated
+// with the contract from the local API.
+func (b *ContractBackend) CodeAt(ctx context.Context, contract common.Address, blockNum *big.Int) ([]byte, error) {
+	return b.bcapi.GetCode(ctx, contract, toBlockNumber(blockNum))
+}
+
+// ContractCall implements bind.ContractCaller executing an Ethereum contract
+// call with the specified data as the input. The pending flag requests execution
+// against the pending block, not the stable head of the chain.
+func (b *ContractBackend) CallContract(ctx context.Context, msg ethereum.CallMsg, blockNum *big.Int) ([]byte, error) {
+	out, err := b.bcapi.Call(ctx, toCallArgs(msg), toBlockNumber(blockNum))
+	return out, err
+}
+
+// PendingCodeAt implements bind.ContractTransactor retrieving any code associated
+// with the contract from the local API.
+func (b *ContractBackend) PendingCodeAt(ctx context.Context, contract common.Address) ([]byte, error) {
+	return b.bcapi.GetCode(ctx, contract, rpc.PendingBlockNumber)
+}
+
+// PendingAccountNonce implements bind.ContractTransactor retrieving the current
+// pending nonce associated with an account.
+func (b *ContractBackend) PendingNonceAt(ctx context.Context, account common.Address) (nonce uint64, err error) {
+	out, err := b.txapi.GetTransactionCount(ctx, account, rpc.PendingBlockNumber)
+	if out != nil {
+		nonce = uint64(*out)
+	}
+	return nonce, err
+}
+
+// SuggestGasPrice implements bind.ContractTransactor retrieving the currently
+// suggested gas price to allow a timely execution of a transaction.
+func (b *ContractBackend) SuggestGasPrice(ctx context.Context) (*big.Int, error) {
+	return b.eapi.GasPrice(ctx)
+}
+
+// EstimateGasLimit implements bind.ContractTransactor trying to estimate the gas
+// needed to execute a specific transaction based on the current pending state of
+// the backend blockchain. There is no guarantee that this is the true gas limit
+// requirement as other transactions may be added or removed by miners, but it
+// should provide a basis for setting a reasonable default.
+func (b *ContractBackend) EstimateGas(ctx context.Context, msg ethereum.CallMsg) (uint64, error) {
+	gas, err := b.bcapi.EstimateGas(ctx, toCallArgs(msg))
+	return uint64(gas), err
+}
+
+// SendTransaction implements bind.ContractTransactor injecting the transaction
+// into the pending pool for execution.
+func (b *ContractBackend) SendTransaction(ctx context.Context, tx *types.Transaction) error {
+	raw, _ := rlp.EncodeToBytes(tx)
+	_, err := b.txapi.SendRawTransaction(ctx, raw)
+	return err
+}
+
+// FilterLogs implements bind.ContractFilterer returning logs matching the given argument
+// that are stored within the state.
+func (b *ContractBackend) FilterLogs(ctx context.Context, query ethereum.FilterQuery) ([]types.Log, error) {
+	ret, err := b.filterapi.GetLogs(ctx, filters.FilterCriteria(query))
+	if err != nil {
+		return nil, err
+	}
+	logs := make([]types.Log, len(ret))
+	for idx, log := range ret {
+		logs[idx] = *log
+	}
+	return logs, nil
+}
+
+// SubscribeFilterLogs implements bind.ContractFilterer watching new fired logs matching the given argument.
+func (b *ContractBackend) 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.filterapi.EventSystem().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 _, log := range logs {
+					select {
+					case ch <- *log:
+					case err := <-sub.Err():
+						return err
+					case <-quit:
+						return nil
+					}
+				}
+			case err := <-sub.Err():
+				return err
+			case <-quit:
+				return nil
+			}
+		}
+	}), nil
+}
+
+func toCallArgs(msg ethereum.CallMsg) ethapi.CallArgs {
+	args := ethapi.CallArgs{
+		To:   msg.To,
+		From: msg.From,
+		Data: msg.Data,
+		Gas:  hexutil.Uint64(msg.Gas),
+	}
+	if msg.GasPrice != nil {
+		args.GasPrice = hexutil.Big(*msg.GasPrice)
+	}
+	if msg.Value != nil {
+		args.Value = hexutil.Big(*msg.Value)
+	}
+	return args
+}
+
+func toBlockNumber(num *big.Int) rpc.BlockNumber {
+	if num == nil {
+		return rpc.LatestBlockNumber
+	}
+	return rpc.BlockNumber(num.Int64())
+}

eth/filters/api.go

@@ -75,6 +75,11 @@ func NewPublicFilterAPI(backend Backend, lightMode bool) *PublicFilterAPI {
 	return api
 }
 
+// EventSystem returns
+func (filter *PublicFilterAPI) EventSystem() *EventSystem {
+	return filter.events
+}
+
 // timeoutLoop runs every 5 minutes and deletes filters that have not been recently used.
 // Tt is started when the api is created.
 func (api *PublicFilterAPI) timeoutLoop() {

internal/ethapi/backend.go

@@ -24,6 +24,7 @@ import (
 	"github.com/ethereum/go-ethereum/accounts"
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/core"
+	"github.com/ethereum/go-ethereum/core/bloombits"
 	"github.com/ethereum/go-ethereum/core/state"
 	"github.com/ethereum/go-ethereum/core/types"
 	"github.com/ethereum/go-ethereum/core/vm"
@@ -44,6 +45,8 @@ type Backend interface {
 	ChainDb() ethdb.Database
 	EventMux() *event.TypeMux
 	AccountManager() *accounts.Manager
+	BloomStatus() (uint64, uint64)
+	ServiceFilter(ctx context.Context, session *bloombits.MatcherSession)
 
 	// BlockChain API
 	SetHead(number uint64)