[WIP] structure/dep refactor

core/chain.go

@@ -0,0 +1,124 @@
+package core
+
+import (
+	"math/big"
+
+	ethcommon "github.com/ethereum/go-ethereum/common"
+	ethconsensus "github.com/ethereum/go-ethereum/consensus"
+	ethstate "github.com/ethereum/go-ethereum/core/state"
+	ethtypes "github.com/ethereum/go-ethereum/core/types"
+	ethrpc "github.com/ethereum/go-ethereum/rpc"
+)
+
+// ChainContext implements Ethereum's core.ChainContext and consensus.Engine
+// interfaces. It is needed in order to apply and process Ethereum
+// transactions. There should only be a single implementation in Ethermint. For
+// the purposes of Ethermint, it should be support retrieving headers and
+// consensus parameters from  the current blockchain to be used during
+// transaction processing.
+//
+// NOTE: Ethermint will distribute the fees out to validators, so the structure
+// and functionality of this is a WIP and subject to change.
+type ChainContext struct {
+	coinbase ethcommon.Address
+}
+
+// Engine implements Ethereum's core.ChainContext interface. As a ChainContext
+// implements the consensus.Engine interface, it is simply returned.
+func (cc *ChainContext) Engine() ethconsensus.Engine {
+	return cc
+}
+
+// GetHeader implements Ethereum's core.ChainContext interface. It currently
+// performs a no-op.
+//
+// TODO: The Cosmos SDK supports retreiving such information in contexts and
+// multi-store, so this will be need to be integrated.
+func (cc *ChainContext) GetHeader(ethcommon.Hash, uint64) *ethtypes.Header {
+	return nil
+}
+
+// Author implements Ethereum's consensus.Engine interface. It is responsible
+// for returned the address of the validtor to receive any fees. This function
+// is only invoked if the given author in the ApplyTransaction call is nil.
+//
+// NOTE: Ethermint will distribute the fees out to validators, so the structure
+// and functionality of this is a WIP and subject to change.
+func (cc *ChainContext) Author(_ *ethtypes.Header) (ethcommon.Address, error) {
+	return cc.coinbase, nil
+}
+
+// APIs implements Ethereum's core.ChainContext interface. It currently
+// performs a no-op.
+//
+// TODO: Do we need to support such RPC APIs? This will tie into a bigger
+// discussion on if we want to support web3.
+func (cc *ChainContext) APIs(_ ethconsensus.ChainReader) []ethrpc.API {
+	return nil
+}
+
+// CalcDifficulty implements Ethereum's core.ChainContext interface. It
+// currently performs a no-op.
+func (cc *ChainContext) CalcDifficulty(_ ethconsensus.ChainReader, _ uint64, _ *ethtypes.Header) *big.Int {
+	return nil
+}
+
+// Finalize implements Ethereum's core.ChainContext interface. It currently
+// performs a no-op.
+//
+// TODO: Figure out if this needs to be hooked up to any part of the ABCI?
+func (cc *ChainContext) Finalize(
+	_ ethconsensus.ChainReader, _ *ethtypes.Header, _ *ethstate.StateDB,
+	_ []*ethtypes.Transaction, _ []*ethtypes.Header, _ []*ethtypes.Receipt,
+) (*ethtypes.Block, error) {
+	return nil, nil
+}
+
+// Prepare implements Ethereum's core.ChainContext interface. It currently
+// performs a no-op.
+//
+// TODO: Figure out if this needs to be hooked up to any part of the ABCI?
+func (cc *ChainContext) Prepare(_ ethconsensus.ChainReader, _ *ethtypes.Header) error {
+	return nil
+}
+
+// Seal implements Ethereum's core.ChainContext interface. It currently
+// performs a no-op.
+//
+// TODO: Figure out if this needs to be hooked up to any part of the ABCI?
+func (cc *ChainContext) Seal(_ ethconsensus.ChainReader, _ *ethtypes.Block, _ <-chan struct{}) (*ethtypes.Block, error) {
+	return nil, nil
+}
+
+// VerifyHeader implements Ethereum's core.ChainContext interface. It currently
+// performs a no-op.
+//
+// TODO: Figure out if this needs to be hooked up to any part of the Cosmos SDK
+// handlers?
+func (cc *ChainContext) VerifyHeader(_ ethconsensus.ChainReader, _ *ethtypes.Header, _ bool) error {
+	return nil
+}
+
+// VerifyHeaders implements Ethereum's core.ChainContext interface. It
+// currently performs a no-op.
+//
+// TODO: Figure out if this needs to be hooked up to any part of the Cosmos SDK
+// handlers?
+func (cc *ChainContext) VerifyHeaders(_ ethconsensus.ChainReader, _ []*ethtypes.Header, _ []bool) (chan<- struct{}, <-chan error) {
+	return nil, nil
+}
+
+// VerifySeal implements Ethereum's core.ChainContext interface. It currently
+// performs a no-op.
+//
+// TODO: Figure out if this needs to be hooked up to any part of the Cosmos SDK
+// handlers?
+func (cc *ChainContext) VerifySeal(_ ethconsensus.ChainReader, _ *ethtypes.Header) error {
+	return nil
+}
+
+// VerifyUncles implements Ethereum's core.ChainContext interface. It currently
+// performs a no-op.
+func (cc *ChainContext) VerifyUncles(_ ethconsensus.ChainReader, _ *ethtypes.Block) error {
+	return nil
+}

core/ethdb.go

@@ -0,0 +1,65 @@
+package core
+
+import (
+	ethdb "github.com/ethereum/go-ethereum/ethdb"
+	dbm "github.com/tendermint/tendermint/libs/db"
+)
+
+// EthereumDB implements Ethereum's ethdb.Database and ethdb.Batch interfaces.
+// It will be used to facilitate persistence of codeHash => code mappings.
+type EthereumDB struct {
+	codeDB dbm.DB
+}
+
+// Put implements Ethereum's ethdb.Putter interface. It wraps the database
+// write operation supported by both batches and regular databases.
+func (edb *EthereumDB) Put(key []byte, value []byte) error {
+	edb.codeDB.Set(key, value)
+	return nil
+}
+
+// Get implements Ethereum's ethdb.Database interface. It returns a value for a
+// given key.
+func (edb *EthereumDB) Get(key []byte) ([]byte, error) {
+	return edb.codeDB.Get(key), nil
+}
+
+// Has implements Ethereum's ethdb.Database interface. It returns a boolean
+// determining if the underlying database has the given key or not.
+func (edb *EthereumDB) Has(key []byte) (bool, error) {
+	return edb.codeDB.Has(key), nil
+}
+
+// Delete implements Ethereum's ethdb.Database interface. It removes a given
+// key from the underlying database.
+func (edb *EthereumDB) Delete(key []byte) error {
+	edb.codeDB.Delete(key)
+	return nil
+}
+
+// Close implements Ethereum's ethdb.Database interface. It closes the
+// underlying database.
+func (edb *EthereumDB) Close() {
+	edb.codeDB.Close()
+}
+
+// NewBatch implements Ethereum's ethdb.Database interface. It returns a new
+// Batch object used for batch database operations.
+func (edb *EthereumDB) NewBatch() ethdb.Batch {
+	return edb
+}
+
+// ValueSize implements Ethereum's ethdb.Database interface. It performs a
+// no-op.
+func (edb *EthereumDB) ValueSize() int {
+	return 0
+}
+
+// Write implements Ethereum's ethdb.Database interface. It performs a no-op.
+func (edb *EthereumDB) Write() error {
+	return nil
+}
+
+// Reset implements Ethereum's ethdb.Database interface. It performs a no-op.
+func (edb *EthereumDB) Reset() {
+}