leveldb reader

pkg/api.go

@@ -26,14 +26,13 @@ const APIName = "statediff"
 // APIVersion is the version of the state diffing service API
 const APIVersion = "0.0.1"
 
-// PublicStateDiffAPI provides an RPC subscription interface
-// that can be used to stream out state diffs as they
-// are produced by a full node
+// PublicStateDiffAPI provides an RPC interface
+// that can be used to fetch historical diffs from leveldb directly
 type PublicStateDiffAPI struct {
 	sds IService
 }
 
-// NewPublicStateDiffAPI creates an rpc subscription interface for the underlying statediff service
+// NewPublicStateDiffAPI creates an rpc interface for the underlying statediff service
 func NewPublicStateDiffAPI(sds IService) *PublicStateDiffAPI {
 	return &PublicStateDiffAPI{
 		sds: sds,

pkg/reader.go

@@ -0,0 +1,101 @@
+// Copyright © 2020 Vulcanize, Inc
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program 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 Affero General Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with this program. If not, see <http://www.gnu.org/licenses/>.
+
+package statediff
+
+import (
+	"fmt"
+	"math/big"
+
+	"github.com/ethereum/go-ethereum/common"
+	"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/ethdb"
+	"github.com/ethereum/go-ethereum/params"
+)
+
+// LvlDBReader exposes the necessary read functions on lvldb
+type LvlDBReader struct {
+	ethDB         ethdb.Database
+	stateDB       state.Database
+	chainConfig   *params.ChainConfig
+}
+
+// NewLvlDBReader creates a new LvlDBReader
+func NewLvlDBReader(path, ancient string, chainConfig *params.ChainConfig) (*LvlDBReader, error) {
+	edb, err := rawdb.NewLevelDBDatabaseWithFreezer(path, 1024, 256, ancient, "eth-statediff-service")
+	if err != nil {
+		return nil, err
+	}
+	return &LvlDBReader{
+		ethDB: edb,
+		stateDB: state.NewDatabase(edb),
+		chainConfig: chainConfig,
+	}, nil
+}
+
+// GetBlockByHash gets block by hash
+func (ldr *LvlDBReader) GetBlockByHash(hash common.Hash) (*types.Block, error) {
+	height := rawdb.ReadHeaderNumber(ldr.ethDB, hash)
+	if height == nil {
+		return nil, fmt.Errorf("unable to read header height for header hash %s", hash.String())
+	}
+	block := rawdb.ReadBlock(ldr.ethDB, hash, *height)
+	if block == nil {
+		return nil, fmt.Errorf("unable to read block at height %d hash %s", *height, hash.String())
+	}
+	return block, nil
+}
+
+func (ldr *LvlDBReader) GetBlockByNumber(number uint64) (*types.Block, error) {
+	hash := rawdb.ReadCanonicalHash(ldr.ethDB, number)
+	block := rawdb.ReadBlock(ldr.ethDB, hash, number)
+	if block == nil {
+		return nil, fmt.Errorf("unable to read block at height %d hash %s", number, hash.String())
+	}
+	return block, nil
+}
+
+// GetReceiptsByHash gets receipt by hash
+func (ldr *LvlDBReader) GetReceiptsByHash(hash common.Hash) (types.Receipts, error) {
+	number := rawdb.ReadHeaderNumber(ldr.ethDB, hash)
+	if number == nil {
+		return nil, fmt.Errorf("unable to read header height for header hash %s", hash.String())
+	}
+	receipts := rawdb.ReadReceipts(ldr.ethDB, hash, *number, ldr.chainConfig)
+	if receipts == nil {
+		return nil, fmt.Errorf("unable to read receipts at height %d hash %s", number, hash.String())
+	}
+	return receipts, nil
+}
+
+// GetTdByHash gets td by hash
+func (ldr *LvlDBReader) GetTdByHash(hash common.Hash) (*big.Int, error) {
+	number := rawdb.ReadHeaderNumber(ldr.ethDB, hash)
+	if number == nil {
+		return nil, fmt.Errorf("unable to read header height for header hash %s", hash.String())
+	}
+	td := rawdb.ReadTd(ldr.ethDB, hash, *number)
+	if td == nil {
+		return nil, fmt.Errorf("unable to read total difficulty at height %d hash %s", number, hash.String())
+	}
+	return td, nil
+}
+
+// StateDB returns the underlying statedb
+func (ldr *LvlDBReader) StateDB() state.Database {
+	return ldr.stateDB
+}