31 changed files with 1559 additions and 345 deletions
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@ -92,6 +92,10 @@ Ref: https://keepachangelog.com/en/1.0.0/
 * (rpc) [\#1143](https://github.com/evmos/ethermint/pull/1143) Restrict unprotected txs on the node JSON-RPC configuration.
 * (all) [\#1137](https://github.com/evmos/ethermint/pull/1137) Rename go module to `evmos/ethermint`

+### API Breaking
+
+- (json-rpc) [tharsis#1121](https://github.com/tharsis/ethermint/pull/1121) Store eth tx index separately
+
 ### Improvements

 * (deps) [\#1147](https://github.com/evmos/ethermint/pull/1147) Bump Go version to `1.18`.
--- a/default.nix
+++ b/default.nix
@ -17,7 +17,7 @@ in
 buildGoApplication rec {
  inherit pname version tags ldflags;
  src = lib.sourceByRegex ./. [
-    "^(x|app|cmd|client|server|crypto|rpc|types|encoding|ethereum|testutil|version|go.mod|go.sum|gomod2nix.toml)($|/.*)"
+    "^(x|app|cmd|client|server|crypto|rpc|types|encoding|ethereum|indexer|testutil|version|go.mod|go.sum|gomod2nix.toml)($|/.*)"
    "^tests(/.*[.]go)?$"
  ];
  modules = ./gomod2nix.toml;
--- a/docs/api/proto-docs.md
+++ b/docs/api/proto-docs.md
@ -82,6 +82,9 @@
 - [ethermint/types/v1/dynamic_fee.proto](#ethermint/types/v1/dynamic_fee.proto)
    - [ExtensionOptionDynamicFeeTx](#ethermint.types.v1.ExtensionOptionDynamicFeeTx)
  
+- [ethermint/types/v1/indexer.proto](#ethermint/types/v1/indexer.proto)
+    - [TxResult](#ethermint.types.v1.TxResult)
+  
 - [ethermint/types/v1/web3.proto](#ethermint/types/v1/web3.proto)
    - [ExtensionOptionsWeb3Tx](#ethermint.types.v1.ExtensionOptionsWeb3Tx)
  
@ -1168,6 +1171,43 @@ ExtensionOptionDynamicFeeTx is an extension option that specify the maxPrioPrice



+ <!-- end messages -->
+
+ <!-- end enums -->
+
+ <!-- end HasExtensions -->
+
+ <!-- end services -->
+
+
+
+<a name="ethermint/types/v1/indexer.proto"></a>
+<p align="right"><a href="#top">Top</a></p>
+
+## ethermint/types/v1/indexer.proto
+
+
+
+<a name="ethermint.types.v1.TxResult"></a>
+
+### TxResult
+TxResult is the value stored in eth tx indexer
+
+
+| Field | Type | Label | Description |
+| ----- | ---- | ----- | ----------- |
+| `height` | [int64](#int64) |  | the block height |
+| `tx_index` | [uint32](#uint32) |  | cosmos tx index |
+| `msg_index` | [uint32](#uint32) |  | the msg index in a batch tx |
+| `eth_tx_index` | [int32](#int32) |  | eth tx index, the index in the list of valid eth tx in the block, aka. the transaction list returned by eth_getBlock api. |
+| `failed` | [bool](#bool) |  | if the eth tx is failed |
+| `gas_used` | [uint64](#uint64) |  | gas used by tx, if exceeds block gas limit, it's set to gas limit which is what's actually deducted by ante handler. |
+| `cumulative_gas_used` | [uint64](#uint64) |  | the cumulative gas used within current batch tx |
+
+
+
+
+
 <!-- end messages -->

 <!-- end enums -->
--- a/indexer/kv_indexer.go
+++ b/indexer/kv_indexer.go
@ -0,0 +1,230 @@
+package indexer
+
+import (
+	"fmt"
+
+	"github.com/cosmos/cosmos-sdk/client"
+	"github.com/cosmos/cosmos-sdk/codec"
+	sdk "github.com/cosmos/cosmos-sdk/types"
+	sdkerrors "github.com/cosmos/cosmos-sdk/types/errors"
+	authante "github.com/cosmos/cosmos-sdk/x/auth/ante"
+	"github.com/ethereum/go-ethereum/common"
+	rpctypes "github.com/evmos/ethermint/rpc/types"
+	abci "github.com/tendermint/tendermint/abci/types"
+	"github.com/tendermint/tendermint/libs/log"
+	tmtypes "github.com/tendermint/tendermint/types"
+	dbm "github.com/tendermint/tm-db"
+
+	ethermint "github.com/evmos/ethermint/types"
+	evmtypes "github.com/evmos/ethermint/x/evm/types"
+)
+
+const (
+	KeyPrefixTxHash  = 1
+	KeyPrefixTxIndex = 2
+
+	// TxIndexKeyLength is the length of tx-index key
+	TxIndexKeyLength = 1 + 8 + 8
+)
+
+var _ ethermint.EVMTxIndexer = &KVIndexer{}
+
+// KVIndexer implements a eth tx indexer on a KV db.
+type KVIndexer struct {
+	db        dbm.DB
+	logger    log.Logger
+	clientCtx client.Context
+}
+
+// NewKVIndexer creates the KVIndexer
+func NewKVIndexer(db dbm.DB, logger log.Logger, clientCtx client.Context) *KVIndexer {
+	return &KVIndexer{db, logger, clientCtx}
+}
+
+// IndexBlock index all the eth txs in a block through the following steps:
+// - Iterates over all of the Txs in Block
+// - Parses eth Tx infos from cosmos-sdk events for every TxResult
+// - Iterates over all the messages of the Tx
+// - Builds and stores a indexer.TxResult based on parsed events for every message
+func (kv *KVIndexer) IndexBlock(block *tmtypes.Block, txResults []*abci.ResponseDeliverTx) error {
+	height := block.Header.Height
+
+	batch := kv.db.NewBatch()
+	defer batch.Close()
+
+	// record index of valid eth tx during the iteration
+	var ethTxIndex int32
+	for txIndex, tx := range block.Txs {
+		result := txResults[txIndex]
+		if !rpctypes.TxSuccessOrExceedsBlockGasLimit(result) {
+			continue
+		}
+
+		tx, err := kv.clientCtx.TxConfig.TxDecoder()(tx)
+		if err != nil {
+			kv.logger.Error("Fail to decode tx", "err", err, "block", height, "txIndex", txIndex)
+			continue
+		}
+
+		if !isEthTx(tx) {
+			continue
+		}
+
+		txs, err := rpctypes.ParseTxResult(result, tx)
+		if err != nil {
+			kv.logger.Error("Fail to parse event", "err", err, "block", height, "txIndex", txIndex)
+			continue
+		}
+
+		var cumulativeGasUsed uint64
+		for msgIndex, msg := range tx.GetMsgs() {
+			ethMsg := msg.(*evmtypes.MsgEthereumTx)
+			txHash := common.HexToHash(ethMsg.Hash)
+
+			txResult := ethermint.TxResult{
+				Height:     height,
+				TxIndex:    uint32(txIndex),
+				MsgIndex:   uint32(msgIndex),
+				EthTxIndex: ethTxIndex,
+			}
+			if result.Code != abci.CodeTypeOK {
+				// exceeds block gas limit scenario, set gas used to gas limit because that's what's charged by ante handler.
+				// some old versions don't emit any events, so workaround here directly.
+				txResult.GasUsed = ethMsg.GetGas()
+				txResult.Failed = true
+			} else {
+				parsedTx := txs.GetTxByMsgIndex(msgIndex)
+				if parsedTx == nil {
+					kv.logger.Error("msg index not found in events", "msgIndex", msgIndex)
+					continue
+				}
+				if parsedTx.EthTxIndex >= 0 && parsedTx.EthTxIndex != ethTxIndex {
+					kv.logger.Error("eth tx index don't match", "expect", ethTxIndex, "found", parsedTx.EthTxIndex)
+				}
+				txResult.GasUsed = parsedTx.GasUsed
+				txResult.Failed = parsedTx.Failed
+			}
+
+			cumulativeGasUsed += txResult.GasUsed
+			txResult.CumulativeGasUsed = cumulativeGasUsed
+			ethTxIndex++
+
+			if err := saveTxResult(kv.clientCtx.Codec, batch, txHash, &txResult); err != nil {
+				return sdkerrors.Wrapf(err, "IndexBlock %d", height)
+			}
+		}
+	}
+	if err := batch.Write(); err != nil {
+		return sdkerrors.Wrapf(err, "IndexBlock %d, write batch", block.Height)
+	}
+	return nil
+}
+
+// LastIndexedBlock returns the latest indexed block number, returns -1 if db is empty
+func (kv *KVIndexer) LastIndexedBlock() (int64, error) {
+	return LoadLastBlock(kv.db)
+}
+
+// FirstIndexedBlock returns the first indexed block number, returns -1 if db is empty
+func (kv *KVIndexer) FirstIndexedBlock() (int64, error) {
+	return LoadFirstBlock(kv.db)
+}
+
+// GetByTxHash finds eth tx by eth tx hash
+func (kv *KVIndexer) GetByTxHash(hash common.Hash) (*ethermint.TxResult, error) {
+	bz, err := kv.db.Get(TxHashKey(hash))
+	if err != nil {
+		return nil, sdkerrors.Wrapf(err, "GetByTxHash %s", hash.Hex())
+	}
+	if len(bz) == 0 {
+		return nil, fmt.Errorf("tx not found, hash: %s", hash.Hex())
+	}
+	var txKey ethermint.TxResult
+	if err := kv.clientCtx.Codec.Unmarshal(bz, &txKey); err != nil {
+		return nil, sdkerrors.Wrapf(err, "GetByTxHash %s", hash.Hex())
+	}
+	return &txKey, nil
+}
+
+// GetByBlockAndIndex finds eth tx by block number and eth tx index
+func (kv *KVIndexer) GetByBlockAndIndex(blockNumber int64, txIndex int32) (*ethermint.TxResult, error) {
+	bz, err := kv.db.Get(TxIndexKey(blockNumber, txIndex))
+	if err != nil {
+		return nil, sdkerrors.Wrapf(err, "GetByBlockAndIndex %d %d", blockNumber, txIndex)
+	}
+	if len(bz) == 0 {
+		return nil, fmt.Errorf("tx not found, block: %d, eth-index: %d", blockNumber, txIndex)
+	}
+	return kv.GetByTxHash(common.BytesToHash(bz))
+}
+
+// TxHashKey returns the key for db entry: `tx hash -> tx result struct`
+func TxHashKey(hash common.Hash) []byte {
+	return append([]byte{KeyPrefixTxHash}, hash.Bytes()...)
+}
+
+// TxIndexKey returns the key for db entry: `(block number, tx index) -> tx hash`
+func TxIndexKey(blockNumber int64, txIndex int32) []byte {
+	bz1 := sdk.Uint64ToBigEndian(uint64(blockNumber))
+	bz2 := sdk.Uint64ToBigEndian(uint64(txIndex))
+	return append(append([]byte{KeyPrefixTxIndex}, bz1...), bz2...)
+}
+
+// LoadLastBlock returns the latest indexed block number, returns -1 if db is empty
+func LoadLastBlock(db dbm.DB) (int64, error) {
+	it, err := db.ReverseIterator([]byte{KeyPrefixTxIndex}, []byte{KeyPrefixTxIndex + 1})
+	if err != nil {
+		return 0, sdkerrors.Wrap(err, "LoadLastBlock")
+	}
+	defer it.Close()
+	if !it.Valid() {
+		return -1, nil
+	}
+	return parseBlockNumberFromKey(it.Key())
+}
+
+// LoadFirstBlock loads the first indexed block, returns -1 if db is empty
+func LoadFirstBlock(db dbm.DB) (int64, error) {
+	it, err := db.Iterator([]byte{KeyPrefixTxIndex}, []byte{KeyPrefixTxIndex + 1})
+	if err != nil {
+		return 0, sdkerrors.Wrap(err, "LoadFirstBlock")
+	}
+	defer it.Close()
+	if !it.Valid() {
+		return -1, nil
+	}
+	return parseBlockNumberFromKey(it.Key())
+}
+
+// isEthTx check if the tx is an eth tx
+func isEthTx(tx sdk.Tx) bool {
+	extTx, ok := tx.(authante.HasExtensionOptionsTx)
+	if !ok {
+		return false
+	}
+	opts := extTx.GetExtensionOptions()
+	if len(opts) != 1 || opts[0].GetTypeUrl() != "/ethermint.evm.v1.ExtensionOptionsEthereumTx" {
+		return false
+	}
+	return true
+}
+
+// saveTxResult index the txResult into the kv db batch
+func saveTxResult(codec codec.Codec, batch dbm.Batch, txHash common.Hash, txResult *ethermint.TxResult) error {
+	bz := codec.MustMarshal(txResult)
+	if err := batch.Set(TxHashKey(txHash), bz); err != nil {
+		return sdkerrors.Wrap(err, "set tx-hash key")
+	}
+	if err := batch.Set(TxIndexKey(txResult.Height, txResult.EthTxIndex), txHash.Bytes()); err != nil {
+		return sdkerrors.Wrap(err, "set tx-index key")
+	}
+	return nil
+}
+
+func parseBlockNumberFromKey(key []byte) (int64, error) {
+	if len(key) != TxIndexKeyLength {
+		return 0, fmt.Errorf("wrong tx index key length, expect: %d, got: %d", TxIndexKeyLength, len(key))
+	}
+
+	return int64(sdk.BigEndianToUint64(key[1:9])), nil
+}
--- a/indexer/kv_indexer_test.go
+++ b/indexer/kv_indexer_test.go
@ -0,0 +1,189 @@
+package indexer_test
+
+import (
+	"math/big"
+	"testing"
+
+	"github.com/cosmos/cosmos-sdk/client"
+	"github.com/cosmos/cosmos-sdk/simapp/params"
+	"github.com/ethereum/go-ethereum/common"
+	ethtypes "github.com/ethereum/go-ethereum/core/types"
+	"github.com/evmos/ethermint/app"
+	"github.com/evmos/ethermint/crypto/ethsecp256k1"
+	evmenc "github.com/evmos/ethermint/encoding"
+	"github.com/evmos/ethermint/indexer"
+	"github.com/evmos/ethermint/tests"
+	"github.com/evmos/ethermint/x/evm/types"
+	"github.com/stretchr/testify/require"
+	abci "github.com/tendermint/tendermint/abci/types"
+	tmlog "github.com/tendermint/tendermint/libs/log"
+	tmtypes "github.com/tendermint/tendermint/types"
+	dbm "github.com/tendermint/tm-db"
+)
+
+func TestKVIndexer(t *testing.T) {
+	priv, err := ethsecp256k1.GenerateKey()
+	require.NoError(t, err)
+	from := common.BytesToAddress(priv.PubKey().Address().Bytes())
+	signer := tests.NewSigner(priv)
+	ethSigner := ethtypes.LatestSignerForChainID(nil)
+
+	to := common.BigToAddress(big.NewInt(1))
+	tx := types.NewTx(
+		nil, 0, &to, big.NewInt(1000), 21000, nil, nil, nil, nil, nil,
+	)
+	tx.From = from.Hex()
+	require.NoError(t, tx.Sign(ethSigner, signer))
+	txHash := tx.AsTransaction().Hash()
+
+	encodingConfig := MakeEncodingConfig()
+	clientCtx := client.Context{}.WithTxConfig(encodingConfig.TxConfig).WithCodec(encodingConfig.Codec)
+
+	// build cosmos-sdk wrapper tx
+	tmTx, err := tx.BuildTx(clientCtx.TxConfig.NewTxBuilder(), "aphoton")
+	require.NoError(t, err)
+	txBz, err := clientCtx.TxConfig.TxEncoder()(tmTx)
+	require.NoError(t, err)
+
+	// build an invalid wrapper tx
+	builder := clientCtx.TxConfig.NewTxBuilder()
+	require.NoError(t, builder.SetMsgs(tx))
+	tmTx2 := builder.GetTx()
+	txBz2, err := clientCtx.TxConfig.TxEncoder()(tmTx2)
+	require.NoError(t, err)
+
+	testCases := []struct {
+		name        string
+		block       *tmtypes.Block
+		blockResult []*abci.ResponseDeliverTx
+		expSuccess  bool
+	}{
+		{
+			"success, format 1",
+			&tmtypes.Block{Header: tmtypes.Header{Height: 1}, Data: tmtypes.Data{Txs: []tmtypes.Tx{txBz}}},
+			[]*abci.ResponseDeliverTx{
+				&abci.ResponseDeliverTx{
+					Code: 0,
+					Events: []abci.Event{
+						{Type: types.EventTypeEthereumTx, Attributes: []abci.EventAttribute{
+							{Key: []byte("ethereumTxHash"), Value: []byte(txHash.Hex())},
+							{Key: []byte("txIndex"), Value: []byte("0")},
+							{Key: []byte("amount"), Value: []byte("1000")},
+							{Key: []byte("txGasUsed"), Value: []byte("21000")},
+							{Key: []byte("txHash"), Value: []byte("")},
+							{Key: []byte("recipient"), Value: []byte("0x775b87ef5D82ca211811C1a02CE0fE0CA3a455d7")},
+						}},
+					},
+				},
+			},
+			true,
+		},
+		{
+			"success, format 2",
+			&tmtypes.Block{Header: tmtypes.Header{Height: 1}, Data: tmtypes.Data{Txs: []tmtypes.Tx{txBz}}},
+			[]*abci.ResponseDeliverTx{
+				&abci.ResponseDeliverTx{
+					Code: 0,
+					Events: []abci.Event{
+						{Type: types.EventTypeEthereumTx, Attributes: []abci.EventAttribute{
+							{Key: []byte("ethereumTxHash"), Value: []byte(txHash.Hex())},
+							{Key: []byte("txIndex"), Value: []byte("0")},
+						}},
+						{Type: types.EventTypeEthereumTx, Attributes: []abci.EventAttribute{
+							{Key: []byte("amount"), Value: []byte("1000")},
+							{Key: []byte("txGasUsed"), Value: []byte("21000")},
+							{Key: []byte("txHash"), Value: []byte("14A84ED06282645EFBF080E0B7ED80D8D8D6A36337668A12B5F229F81CDD3F57")},
+							{Key: []byte("recipient"), Value: []byte("0x775b87ef5D82ca211811C1a02CE0fE0CA3a455d7")},
+						}},
+					},
+				},
+			},
+			true,
+		},
+		{
+			"success, exceed block gas limit",
+			&tmtypes.Block{Header: tmtypes.Header{Height: 1}, Data: tmtypes.Data{Txs: []tmtypes.Tx{txBz}}},
+			[]*abci.ResponseDeliverTx{
+				&abci.ResponseDeliverTx{
+					Code:   11,
+					Log:    "out of gas in location: block gas meter; gasWanted: 21000",
+					Events: []abci.Event{},
+				},
+			},
+			true,
+		},
+		{
+			"fail, failed eth tx",
+			&tmtypes.Block{Header: tmtypes.Header{Height: 1}, Data: tmtypes.Data{Txs: []tmtypes.Tx{txBz}}},
+			[]*abci.ResponseDeliverTx{
+				&abci.ResponseDeliverTx{
+					Code:   15,
+					Log:    "nonce mismatch",
+					Events: []abci.Event{},
+				},
+			},
+			false,
+		},
+		{
+			"fail, invalid events",
+			&tmtypes.Block{Header: tmtypes.Header{Height: 1}, Data: tmtypes.Data{Txs: []tmtypes.Tx{txBz}}},
+			[]*abci.ResponseDeliverTx{
+				&abci.ResponseDeliverTx{
+					Code:   0,
+					Events: []abci.Event{},
+				},
+			},
+			false,
+		},
+		{
+			"fail, not eth tx",
+			&tmtypes.Block{Header: tmtypes.Header{Height: 1}, Data: tmtypes.Data{Txs: []tmtypes.Tx{txBz2}}},
+			[]*abci.ResponseDeliverTx{
+				&abci.ResponseDeliverTx{
+					Code:   0,
+					Events: []abci.Event{},
+				},
+			},
+			false,
+		},
+	}
+
+	for _, tc := range testCases {
+		t.Run(tc.name, func(t *testing.T) {
+			db := dbm.NewMemDB()
+			idxer := indexer.NewKVIndexer(db, tmlog.NewNopLogger(), clientCtx)
+
+			err = idxer.IndexBlock(tc.block, tc.blockResult)
+			require.NoError(t, err)
+			if !tc.expSuccess {
+				first, err := idxer.FirstIndexedBlock()
+				require.NoError(t, err)
+				require.Equal(t, int64(-1), first)
+
+				last, err := idxer.LastIndexedBlock()
+				require.NoError(t, err)
+				require.Equal(t, int64(-1), last)
+			} else {
+				first, err := idxer.FirstIndexedBlock()
+				require.NoError(t, err)
+				require.Equal(t, tc.block.Header.Height, first)
+
+				last, err := idxer.LastIndexedBlock()
+				require.NoError(t, err)
+				require.Equal(t, tc.block.Header.Height, last)
+
+				res1, err := idxer.GetByTxHash(txHash)
+				require.NoError(t, err)
+				require.NotNil(t, res1)
+				res2, err := idxer.GetByBlockAndIndex(1, 0)
+				require.NoError(t, err)
+				require.Equal(t, res1, res2)
+			}
+		})
+	}
+}
+
+// MakeEncodingConfig creates the EncodingConfig
+func MakeEncodingConfig() params.EncodingConfig {
+	return evmenc.MakeConfig(app.ModuleBasics)
+}
--- a/proto/ethermint/types/v1/indexer.proto
+++ b/proto/ethermint/types/v1/indexer.proto
@ -0,0 +1,29 @@
+syntax = "proto3";
+package ethermint.types.v1;
+
+import "gogoproto/gogo.proto";
+
+option go_package = "github.com/evmos/ethermint/types";
+
+// TxResult is the value stored in eth tx indexer
+message TxResult {
+    option (gogoproto.goproto_getters) = false;
+
+    // the block height
+    int64 height = 1;
+    // cosmos tx index
+    uint32 tx_index = 2;
+    // the msg index in a batch tx
+    uint32 msg_index = 3;
+
+    // eth tx index, the index in the list of valid eth tx in the block, 
+    // aka. the transaction list returned by eth_getBlock api.
+    int32 eth_tx_index = 4;
+    // if the eth tx is failed
+    bool failed = 5;
+    // gas used by tx, if exceeds block gas limit,
+    // it's set to gas limit which is what's actually deducted by ante handler.
+    uint64 gas_used = 6;
+    // the cumulative gas used within current batch tx
+    uint64 cumulative_gas_used = 7;
+}
--- a/rpc/apis.go
+++ b/rpc/apis.go
@ -19,6 +19,7 @@ import (
 	"github.com/evmos/ethermint/rpc/namespaces/ethereum/personal"
 	"github.com/evmos/ethermint/rpc/namespaces/ethereum/txpool"
 	"github.com/evmos/ethermint/rpc/namespaces/ethereum/web3"
+	ethermint "github.com/evmos/ethermint/types"

 	rpcclient "github.com/tendermint/tendermint/rpc/jsonrpc/client"
 )
@ -48,6 +49,7 @@ type APICreator = func(
 	clientCtx client.Context,
 	tendermintWebsocketClient *rpcclient.WSClient,
 	allowUnprotectedTxs bool,
+	indexer ethermint.EVMTxIndexer,
 ) []rpc.API

 // apiCreators defines the JSON-RPC API namespaces.
@ -55,8 +57,8 @@ var apiCreators map[string]APICreator

 func init() {
 	apiCreators = map[string]APICreator{
-		EthNamespace: func(ctx *server.Context, clientCtx client.Context, tmWSClient *rpcclient.WSClient, allowUnprotectedTxs bool) []rpc.API {
-			evmBackend := backend.NewBackend(ctx, ctx.Logger, clientCtx, allowUnprotectedTxs)
+		EthNamespace: func(ctx *server.Context, clientCtx client.Context, tmWSClient *rpcclient.WSClient, allowUnprotectedTxs bool, indexer ethermint.EVMTxIndexer) []rpc.API {
+			evmBackend := backend.NewBackend(ctx, ctx.Logger, clientCtx, allowUnprotectedTxs, indexer)
 			return []rpc.API{
 				{
 					Namespace: EthNamespace,
@ -72,7 +74,7 @@ func init() {
 				},
 			}
 		},
-		Web3Namespace: func(*server.Context, client.Context, *rpcclient.WSClient, bool) []rpc.API {
+		Web3Namespace: func(*server.Context, client.Context, *rpcclient.WSClient, bool, ethermint.EVMTxIndexer) []rpc.API {
 			return []rpc.API{
 				{
 					Namespace: Web3Namespace,
@ -82,7 +84,7 @@ func init() {
 				},
 			}
 		},
-		NetNamespace: func(_ *server.Context, clientCtx client.Context, _ *rpcclient.WSClient, _ bool) []rpc.API {
+		NetNamespace: func(_ *server.Context, clientCtx client.Context, _ *rpcclient.WSClient, _ bool, _ ethermint.EVMTxIndexer) []rpc.API {
 			return []rpc.API{
 				{
 					Namespace: NetNamespace,
@ -92,8 +94,8 @@ func init() {
 				},
 			}
 		},
-		PersonalNamespace: func(ctx *server.Context, clientCtx client.Context, _ *rpcclient.WSClient, allowUnprotectedTxs bool) []rpc.API {
-			evmBackend := backend.NewBackend(ctx, ctx.Logger, clientCtx, allowUnprotectedTxs)
+		PersonalNamespace: func(ctx *server.Context, clientCtx client.Context, _ *rpcclient.WSClient, allowUnprotectedTxs bool, indexer ethermint.EVMTxIndexer) []rpc.API {
+			evmBackend := backend.NewBackend(ctx, ctx.Logger, clientCtx, allowUnprotectedTxs, indexer)
 			return []rpc.API{
 				{
 					Namespace: PersonalNamespace,
@ -103,7 +105,7 @@ func init() {
 				},
 			}
 		},
-		TxPoolNamespace: func(ctx *server.Context, _ client.Context, _ *rpcclient.WSClient, _ bool) []rpc.API {
+		TxPoolNamespace: func(ctx *server.Context, _ client.Context, _ *rpcclient.WSClient, _ bool, _ ethermint.EVMTxIndexer) []rpc.API {
 			return []rpc.API{
 				{
 					Namespace: TxPoolNamespace,
@ -113,8 +115,8 @@ func init() {
 				},
 			}
 		},
-		DebugNamespace: func(ctx *server.Context, clientCtx client.Context, _ *rpcclient.WSClient, allowUnprotectedTxs bool) []rpc.API {
-			evmBackend := backend.NewBackend(ctx, ctx.Logger, clientCtx, allowUnprotectedTxs)
+		DebugNamespace: func(ctx *server.Context, clientCtx client.Context, _ *rpcclient.WSClient, allowUnprotectedTxs bool, indexer ethermint.EVMTxIndexer) []rpc.API {
+			evmBackend := backend.NewBackend(ctx, ctx.Logger, clientCtx, allowUnprotectedTxs, indexer)
 			return []rpc.API{
 				{
 					Namespace: DebugNamespace,
@ -124,8 +126,8 @@ func init() {
 				},
 			}
 		},
-		MinerNamespace: func(ctx *server.Context, clientCtx client.Context, _ *rpcclient.WSClient, allowUnprotectedTxs bool) []rpc.API {
-			evmBackend := backend.NewBackend(ctx, ctx.Logger, clientCtx, allowUnprotectedTxs)
+		MinerNamespace: func(ctx *server.Context, clientCtx client.Context, _ *rpcclient.WSClient, allowUnprotectedTxs bool, indexer ethermint.EVMTxIndexer) []rpc.API {
+			evmBackend := backend.NewBackend(ctx, ctx.Logger, clientCtx, allowUnprotectedTxs, indexer)
 			return []rpc.API{
 				{
 					Namespace: MinerNamespace,
@ -139,12 +141,12 @@ func init() {
 }

 // GetRPCAPIs returns the list of all APIs
-func GetRPCAPIs(ctx *server.Context, clientCtx client.Context, tmWSClient *rpcclient.WSClient, allowUnprotectedTxs bool, selectedAPIs []string) []rpc.API {
+func GetRPCAPIs(ctx *server.Context, clientCtx client.Context, tmWSClient *rpcclient.WSClient, allowUnprotectedTxs bool, indexer ethermint.EVMTxIndexer, selectedAPIs []string) []rpc.API {
 	var apis []rpc.API

 	for _, ns := range selectedAPIs {
 		if creator, ok := apiCreators[ns]; ok {
-			apis = append(apis, creator(ctx, clientCtx, tmWSClient, allowUnprotectedTxs)...)
+			apis = append(apis, creator(ctx, clientCtx, tmWSClient, allowUnprotectedTxs, indexer)...)
 		} else {
 			ctx.Logger.Error("invalid namespace value", "namespace", ns)
 		}
--- a/rpc/backend/backend.go
+++ b/rpc/backend/backend.go
@ -103,8 +103,8 @@ type EVMBackend interface {

 	// Tx Info
 	GetTransactionByHash(txHash common.Hash) (*rpctypes.RPCTransaction, error)
-	GetTxByEthHash(txHash common.Hash) (*tmrpctypes.ResultTx, error)
-	GetTxByTxIndex(height int64, txIndex uint) (*tmrpctypes.ResultTx, error)
+	GetTxByEthHash(txHash common.Hash) (*ethermint.TxResult, error)
+	GetTxByTxIndex(height int64, txIndex uint) (*ethermint.TxResult, error)
 	GetTransactionByBlockAndIndex(block *tmrpctypes.ResultBlock, idx hexutil.Uint) (*rpctypes.RPCTransaction, error)
 	GetTransactionReceipt(hash common.Hash) (map[string]interface{}, error)
 	GetTransactionByBlockHashAndIndex(hash common.Hash, idx hexutil.Uint) (*rpctypes.RPCTransaction, error)
@ -140,10 +140,17 @@ type Backend struct {
 	chainID             *big.Int
 	cfg                 config.Config
 	allowUnprotectedTxs bool
+	indexer             ethermint.EVMTxIndexer
 }

 // NewBackend creates a new Backend instance for cosmos and ethereum namespaces
-func NewBackend(ctx *server.Context, logger log.Logger, clientCtx client.Context, allowUnprotectedTxs bool) *Backend {
+func NewBackend(
+	ctx *server.Context,
+	logger log.Logger,
+	clientCtx client.Context,
+	allowUnprotectedTxs bool,
+	indexer ethermint.EVMTxIndexer,
+) *Backend {
 	chainID, err := ethermint.ParseChainID(clientCtx.ChainID)
 	if err != nil {
 		panic(err)
@ -176,5 +183,6 @@ func NewBackend(ctx *server.Context, logger log.Logger, clientCtx client.Context
 		chainID:             chainID,
 		cfg:                 appConf,
 		allowUnprotectedTxs: allowUnprotectedTxs,
+		indexer:             indexer,
 	}
 }
--- a/rpc/backend/backend_suite_test.go
+++ b/rpc/backend/backend_suite_test.go
@ -8,6 +8,8 @@ import (
 	"path/filepath"
 	"testing"

+	dbm "github.com/tendermint/tm-db"
+
 	"github.com/cosmos/cosmos-sdk/client"
 	"github.com/cosmos/cosmos-sdk/crypto/keyring"
 	"github.com/cosmos/cosmos-sdk/server"
@ -20,6 +22,7 @@ import (
 	"github.com/evmos/ethermint/app"
 	"github.com/evmos/ethermint/crypto/hd"
 	"github.com/evmos/ethermint/encoding"
+	"github.com/evmos/ethermint/indexer"
 	"github.com/evmos/ethermint/rpc/backend/mocks"
 	rpctypes "github.com/evmos/ethermint/rpc/types"
 	evmtypes "github.com/evmos/ethermint/x/evm/types"
@ -56,7 +59,9 @@ func (suite *BackendTestSuite) SetupTest() {

 	allowUnprotectedTxs := false

-	suite.backend = NewBackend(ctx, ctx.Logger, clientCtx, allowUnprotectedTxs)
+	idxer := indexer.NewKVIndexer(dbm.NewMemDB(), ctx.Logger, clientCtx)
+
+	suite.backend = NewBackend(ctx, ctx.Logger, clientCtx, allowUnprotectedTxs, idxer)
 	suite.backend.queryClient.QueryClient = mocks.NewQueryClient(suite.T())
 	suite.backend.clientCtx.Client = mocks.NewClient(suite.T())
 	suite.backend.ctx = rpctypes.ContextWithHeight(1)
--- a/rpc/backend/blocks_info.go
+++ b/rpc/backend/blocks_info.go
@ -297,7 +297,7 @@ func (b *Backend) GetEthereumMsgsFromTendermintBlock(
 		// Check if tx exists on EVM by cross checking with blockResults:
 		//  - Include unsuccessful tx that exceeds block gas limit
 		//  - Exclude unsuccessful tx with any other error but ExceedBlockGasLimit
-		if !TxSuccessOrExceedsBlockGasLimit(txResults[i]) {
+		if !rpctypes.TxSuccessOrExceedsBlockGasLimit(txResults[i]) {
 			b.logger.Debug("invalid tx result code", "cosmos-hash", hexutil.Encode(tx.Hash()))
 			continue
 		}
--- a/rpc/backend/evm_backend_test.go
+++ b/rpc/backend/evm_backend_test.go
@ -949,7 +949,7 @@ func (suite *BackendTestSuite) TestGetEthereumMsgsFromTendermintBlock() {
 				TxsResults: []*types.ResponseDeliverTx{
 					{
 						Code: 1,
-						Log:  ExceedBlockGasLimitError,
+						Log:  ethrpc.ExceedBlockGasLimitError,
 					},
 				},
 			},
@ -964,7 +964,7 @@ func (suite *BackendTestSuite) TestGetEthereumMsgsFromTendermintBlock() {
 				TxsResults: []*types.ResponseDeliverTx{
 					{
 						Code: 0,
-						Log:  ExceedBlockGasLimitError,
+						Log:  ethrpc.ExceedBlockGasLimitError,
 					},
 				},
 			},
--- a/rpc/backend/tracing.go
+++ b/rpc/backend/tracing.go
@ -32,23 +32,14 @@ func (b *Backend) TraceTransaction(hash common.Hash, config *evmtypes.TraceConfi
 		return nil, err
 	}

-	parsedTxs, err := rpctypes.ParseTxResult(&transaction.TxResult)
-	if err != nil {
-		return nil, fmt.Errorf("failed to parse tx events: %s", hash.Hex())
-	}
-	parsedTx := parsedTxs.GetTxByHash(hash)
-	if parsedTx == nil {
-		return nil, fmt.Errorf("ethereum tx not found in msgs: %s", hash.Hex())
-	}
-
 	// check tx index is not out of bound
-	if uint32(len(blk.Block.Txs)) < transaction.Index {
-		b.logger.Debug("tx index out of bounds", "index", transaction.Index, "hash", hash.String(), "height", blk.Block.Height)
+	if uint32(len(blk.Block.Txs)) < transaction.TxIndex {
+		b.logger.Debug("tx index out of bounds", "index", transaction.TxIndex, "hash", hash.String(), "height", blk.Block.Height)
 		return nil, fmt.Errorf("transaction not included in block %v", blk.Block.Height)
 	}

 	var predecessors []*evmtypes.MsgEthereumTx
-	for _, txBz := range blk.Block.Txs[:transaction.Index] {
+	for _, txBz := range blk.Block.Txs[:transaction.TxIndex] {
 		tx, err := b.clientCtx.TxConfig.TxDecoder()(txBz)
 		if err != nil {
 			b.logger.Debug("failed to decode transaction in block", "height", blk.Block.Height, "error", err.Error())
@ -64,14 +55,14 @@ func (b *Backend) TraceTransaction(hash common.Hash, config *evmtypes.TraceConfi
 		}
 	}

-	tx, err := b.clientCtx.TxConfig.TxDecoder()(transaction.Tx)
+	tx, err := b.clientCtx.TxConfig.TxDecoder()(blk.Block.Txs[transaction.TxIndex])
 	if err != nil {
 		b.logger.Debug("tx not found", "hash", hash)
 		return nil, err
 	}

 	// add predecessor messages in current cosmos tx
-	for i := 0; i < parsedTx.MsgIndex; i++ {
+	for i := 0; i < int(transaction.MsgIndex); i++ {
 		ethMsg, ok := tx.GetMsgs()[i].(*evmtypes.MsgEthereumTx)
 		if !ok {
 			continue
@ -79,7 +70,7 @@ func (b *Backend) TraceTransaction(hash common.Hash, config *evmtypes.TraceConfi
 		predecessors = append(predecessors, ethMsg)
 	}

-	ethMessage, ok := tx.GetMsgs()[parsedTx.MsgIndex].(*evmtypes.MsgEthereumTx)
+	ethMessage, ok := tx.GetMsgs()[transaction.MsgIndex].(*evmtypes.MsgEthereumTx)
 	if !ok {
 		b.logger.Debug("invalid transaction type", "type", fmt.Sprintf("%T", tx))
 		return nil, fmt.Errorf("invalid transaction type %T", tx)
--- a/rpc/backend/tx_info.go
+++ b/rpc/backend/tx_info.go
@ -3,11 +3,14 @@ package backend
 import (
 	"fmt"

+	sdk "github.com/cosmos/cosmos-sdk/types"
+	sdkerrors "github.com/cosmos/cosmos-sdk/types/errors"
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/common/hexutil"
 	ethtypes "github.com/ethereum/go-ethereum/core/types"
 	"github.com/ethereum/go-ethereum/crypto"
 	rpctypes "github.com/evmos/ethermint/rpc/types"
+	ethermint "github.com/evmos/ethermint/types"
 	evmtypes "github.com/evmos/ethermint/x/evm/types"
 	"github.com/pkg/errors"
 	tmrpctypes "github.com/tendermint/tendermint/rpc/core/types"
@ -19,6 +22,64 @@ func (b *Backend) GetTransactionByHash(txHash common.Hash) (*rpctypes.RPCTransac
 	hexTx := txHash.Hex()

 	if err != nil {
+		return b.getTransactionByHashPending(txHash)
+	}
+
+	block, err := b.GetTendermintBlockByNumber(rpctypes.BlockNumber(res.Height))
+	if err != nil {
+		return nil, err
+	}
+
+	tx, err := b.clientCtx.TxConfig.TxDecoder()(block.Block.Txs[res.TxIndex])
+	if err != nil {
+		return nil, err
+	}
+
+	// the `res.MsgIndex` is inferred from tx index, should be within the bound.
+	msg, ok := tx.GetMsgs()[res.MsgIndex].(*evmtypes.MsgEthereumTx)
+	if !ok {
+		return nil, errors.New("invalid ethereum tx")
+	}
+
+	blockRes, err := b.GetTendermintBlockResultByNumber(&block.Block.Height)
+	if err != nil {
+		b.logger.Debug("block result not found", "height", block.Block.Height, "error", err.Error())
+		return nil, nil
+	}
+
+	if res.EthTxIndex == -1 {
+		// Fallback to find tx index by iterating all valid eth transactions
+		msgs := b.GetEthereumMsgsFromTendermintBlock(block, blockRes)
+		for i := range msgs {
+			if msgs[i].Hash == hexTx {
+				res.EthTxIndex = int32(i)
+				break
+			}
+		}
+	}
+	// if we still unable to find the eth tx index, return error, shouldn't happen.
+	if res.EthTxIndex == -1 {
+		return nil, errors.New("can't find index of ethereum tx")
+	}
+
+	baseFee, err := b.BaseFee(blockRes)
+	if err != nil {
+		// handle the error for pruned node.
+		b.logger.Error("failed to fetch Base Fee from prunned block. Check node prunning configuration", "height", blockRes.Height, "error", err)
+	}
+
+	return rpctypes.NewTransactionFromMsg(
+		msg,
+		common.BytesToHash(block.BlockID.Hash.Bytes()),
+		uint64(res.Height),
+		uint64(res.EthTxIndex),
+		baseFee,
+	)
+}
+
+// getTransactionByHashPending find pending tx from mempool
+func (b *Backend) getTransactionByHashPending(txHash common.Hash) (*rpctypes.RPCTransaction, error) {
+	hexTx := txHash.Hex()
 	// try to find tx in mempool
 	txs, err := b.PendingTransactions()
 	if err != nil {
@ -34,6 +95,7 @@ func (b *Backend) GetTransactionByHash(txHash common.Hash) (*rpctypes.RPCTransac
 		}

 		if msg.Hash == hexTx {
+			// use zero block values since it's not included in a block yet
 			rpctx, err := rpctypes.NewTransactionFromMsg(
 				msg,
 				common.Hash{},
@ -52,72 +114,6 @@ func (b *Backend) GetTransactionByHash(txHash common.Hash) (*rpctypes.RPCTransac
 	return nil, nil
 }

-	if !TxSuccessOrExceedsBlockGasLimit(&res.TxResult) {
-		return nil, errors.New("invalid ethereum tx")
-	}
-
-	parsedTxs, err := rpctypes.ParseTxResult(&res.TxResult)
-	if err != nil {
-		return nil, fmt.Errorf("failed to parse tx events: %s", hexTx)
-	}
-
-	parsedTx := parsedTxs.GetTxByHash(txHash)
-	if parsedTx == nil {
-		return nil, fmt.Errorf("ethereum tx not found in msgs: %s", hexTx)
-	}
-
-	tx, err := b.clientCtx.TxConfig.TxDecoder()(res.Tx)
-	if err != nil {
-		return nil, err
-	}
-
-	// the `msgIndex` is inferred from tx events, should be within the bound.
-	msg, ok := tx.GetMsgs()[parsedTx.MsgIndex].(*evmtypes.MsgEthereumTx)
-	if !ok {
-		return nil, errors.New("invalid ethereum tx")
-	}
-
-	block, err := b.clientCtx.Client.Block(b.ctx, &res.Height)
-	if err != nil {
-		b.logger.Debug("block not found", "height", res.Height, "error", err.Error())
-		return nil, err
-	}
-
-	blockRes, err := b.GetTendermintBlockResultByNumber(&block.Block.Height)
-	if err != nil {
-		b.logger.Debug("block result not found", "height", block.Block.Height, "error", err.Error())
-		return nil, nil
-	}
-
-	if parsedTx.EthTxIndex == -1 {
-		// Fallback to find tx index by iterating all valid eth transactions
-		msgs := b.GetEthereumMsgsFromTendermintBlock(block, blockRes)
-		for i := range msgs {
-			if msgs[i].Hash == hexTx {
-				parsedTx.EthTxIndex = int64(i)
-				break
-			}
-		}
-	}
-	if parsedTx.EthTxIndex == -1 {
-		return nil, errors.New("can't find index of ethereum tx")
-	}
-
-	baseFee, err := b.BaseFee(blockRes)
-	if err != nil {
-		// handle the error for pruned node.
-		b.logger.Error("failed to fetch Base Fee from prunned block. Check node prunning configuration", "height", blockRes.Height, "error", err)
-	}
-
-	return rpctypes.NewTransactionFromMsg(
-		msg,
-		common.BytesToHash(block.BlockID.Hash.Bytes()),
-		uint64(res.Height),
-		uint64(parsedTx.EthTxIndex),
-		baseFee,
-	)
-}
-
 // GetTransactionReceipt returns the transaction receipt identified by hash.
 func (b *Backend) GetTransactionReceipt(hash common.Hash) (map[string]interface{}, error) {
 	hexTx := hash.Hex()
@ -129,44 +125,17 @@ func (b *Backend) GetTransactionReceipt(hash common.Hash) (map[string]interface{
 		return nil, nil
 	}

-	// don't ignore the txs which exceed block gas limit.
-	if !TxSuccessOrExceedsBlockGasLimit(&res.TxResult) {
-		return nil, nil
-	}
-
-	parsedTxs, err := rpctypes.ParseTxResult(&res.TxResult)
-	if err != nil {
-		return nil, fmt.Errorf("failed to parse tx events: %s, %v", hexTx, err)
-	}
-
-	parsedTx := parsedTxs.GetTxByHash(hash)
-	if parsedTx == nil {
-		return nil, fmt.Errorf("ethereum tx not found in msgs: %s", hexTx)
-	}
-
-	resBlock, err := b.clientCtx.Client.Block(b.ctx, &res.Height)
+	resBlock, err := b.GetTendermintBlockByNumber(rpctypes.BlockNumber(res.Height))
 	if err != nil {
 		b.logger.Debug("block not found", "height", res.Height, "error", err.Error())
 		return nil, nil
 	}
-
-	tx, err := b.clientCtx.TxConfig.TxDecoder()(res.Tx)
+	tx, err := b.clientCtx.TxConfig.TxDecoder()(resBlock.Block.Txs[res.TxIndex])
 	if err != nil {
 		b.logger.Debug("decoding failed", "error", err.Error())
 		return nil, fmt.Errorf("failed to decode tx: %w", err)
 	}
-
-	if res.TxResult.Code != 0 {
-		// tx failed, we should return gas limit as gas used, because that's how the fee get deducted.
-		for i := 0; i <= parsedTx.MsgIndex; i++ {
-			gasLimit := tx.GetMsgs()[i].(*evmtypes.MsgEthereumTx).GetGas()
-			parsedTxs.Txs[i].GasUsed = gasLimit
-		}
-	}
-
-	// the `msgIndex` is inferred from tx events, should be within the bound,
-	// and the tx is found by eth tx hash, so the msg type must be correct.
-	ethMsg := tx.GetMsgs()[parsedTx.MsgIndex].(*evmtypes.MsgEthereumTx)
+	ethMsg := tx.GetMsgs()[res.MsgIndex].(*evmtypes.MsgEthereumTx)

 	txData, err := evmtypes.UnpackTxData(ethMsg.Data)
 	if err != nil {
@ -180,42 +149,46 @@ func (b *Backend) GetTransactionReceipt(hash common.Hash) (map[string]interface{
 		b.logger.Debug("failed to retrieve block results", "height", res.Height, "error", err.Error())
 		return nil, nil
 	}
-	for i := 0; i < int(res.Index) && i < len(blockRes.TxsResults); i++ {
-		cumulativeGasUsed += uint64(blockRes.TxsResults[i].GasUsed)
+	for _, txResult := range blockRes.TxsResults[0:res.TxIndex] {
+		cumulativeGasUsed += uint64(txResult.GasUsed)
 	}
-	cumulativeGasUsed += parsedTxs.AccumulativeGasUsed(parsedTx.MsgIndex)
+	cumulativeGasUsed += res.CumulativeGasUsed

-	// Get the transaction result from the log
 	var status hexutil.Uint
-	if res.TxResult.Code != 0 || parsedTx.Failed {
+	if res.Failed {
 		status = hexutil.Uint(ethtypes.ReceiptStatusFailed)
 	} else {
 		status = hexutil.Uint(ethtypes.ReceiptStatusSuccessful)
 	}

-	from, err := ethMsg.GetSender(b.chainID)
+	chainID, err := b.ChainID()
+	if err != nil {
+		return nil, err
+	}
+
+	from, err := ethMsg.GetSender(chainID.ToInt())
 	if err != nil {
 		return nil, err
 	}

 	// parse tx logs from events
-	logs, err := parsedTx.ParseTxLogs()
+	logs, err := TxLogsFromEvents(blockRes.TxsResults[res.TxIndex].Events, int(res.MsgIndex))
 	if err != nil {
 		b.logger.Debug("failed to parse logs", "hash", hexTx, "error", err.Error())
 	}

-	if parsedTx.EthTxIndex == -1 {
+	if res.EthTxIndex == -1 {
 		// Fallback to find tx index by iterating all valid eth transactions
 		msgs := b.GetEthereumMsgsFromTendermintBlock(resBlock, blockRes)
 		for i := range msgs {
 			if msgs[i].Hash == hexTx {
-				parsedTx.EthTxIndex = int64(i)
+				res.EthTxIndex = int32(i)
 				break
 			}
 		}
 	}
-
-	if parsedTx.EthTxIndex == -1 {
+	// return error if still unable to find the eth tx index
+	if res.EthTxIndex == -1 {
 		return nil, errors.New("can't find index of ethereum tx")
 	}

@ -230,13 +203,13 @@ func (b *Backend) GetTransactionReceipt(hash common.Hash) (map[string]interface{
 		// They are stored in the chain database.
 		"transactionHash": hash,
 		"contractAddress": nil,
-		"gasUsed":         hexutil.Uint64(parsedTx.GasUsed),
+		"gasUsed":         hexutil.Uint64(res.GasUsed),

 		// Inclusion information: These fields provide information about the inclusion of the
 		// transaction corresponding to this receipt.
 		"blockHash":        common.BytesToHash(resBlock.Block.Header.Hash()).Hex(),
 		"blockNumber":      hexutil.Uint64(res.Height),
-		"transactionIndex": hexutil.Uint64(parsedTx.EthTxIndex),
+		"transactionIndex": hexutil.Uint64(res.EthTxIndex),

 		// sender and receiver (contract or EOA) addreses
 		"from": from,
@ -304,32 +277,66 @@ func (b *Backend) GetTransactionByBlockNumberAndIndex(blockNum rpctypes.BlockNum
 // GetTxByEthHash uses `/tx_query` to find transaction by ethereum tx hash
 // TODO: Don't need to convert once hashing is fixed on Tendermint
 // https://github.com/tendermint/tendermint/issues/6539
-func (b *Backend) GetTxByEthHash(hash common.Hash) (*tmrpctypes.ResultTx, error) {
+func (b *Backend) GetTxByEthHash(hash common.Hash) (*ethermint.TxResult, error) {
+	if b.indexer != nil {
+		return b.indexer.GetByTxHash(hash)
+	}
+
+	// fallback to tendermint tx indexer
 	query := fmt.Sprintf("%s.%s='%s'", evmtypes.TypeMsgEthereumTx, evmtypes.AttributeKeyEthereumTxHash, hash.Hex())
-	resTxs, err := b.clientCtx.Client.TxSearch(b.ctx, query, false, nil, nil, "")
+	txResult, err := b.queryTendermintTxIndexer(query, func(txs *rpctypes.ParsedTxs) *rpctypes.ParsedTx {
+		return txs.GetTxByHash(hash)
+	})
 	if err != nil {
-		return nil, err
+		return nil, sdkerrors.Wrapf(err, "GetTxByEthHash %s", hash.Hex())
 	}
-	if len(resTxs.Txs) == 0 {
-		return nil, errors.Errorf("ethereum tx not found for hash %s", hash.Hex())
-	}
-	return resTxs.Txs[0], nil
+	return txResult, nil
 }

 // GetTxByTxIndex uses `/tx_query` to find transaction by tx index of valid ethereum txs
-func (b *Backend) GetTxByTxIndex(height int64, index uint) (*tmrpctypes.ResultTx, error) {
+func (b *Backend) GetTxByTxIndex(height int64, index uint) (*ethermint.TxResult, error) {
+	if b.indexer != nil {
+		return b.indexer.GetByBlockAndIndex(height, int32(index))
+	}
+
+	// fallback to tendermint tx indexer
 	query := fmt.Sprintf("tx.height=%d AND %s.%s=%d",
 		height, evmtypes.TypeMsgEthereumTx,
 		evmtypes.AttributeKeyTxIndex, index,
 	)
+	txResult, err := b.queryTendermintTxIndexer(query, func(txs *rpctypes.ParsedTxs) *rpctypes.ParsedTx {
+		return txs.GetTxByTxIndex(int(index))
+	})
+	if err != nil {
+		return nil, sdkerrors.Wrapf(err, "GetTxByTxIndex %d %d", height, index)
+	}
+	return txResult, nil
+}
+
+// queryTendermintTxIndexer query tx in tendermint tx indexer
+func (b *Backend) queryTendermintTxIndexer(query string, txGetter func(*rpctypes.ParsedTxs) *rpctypes.ParsedTx) (*ethermint.TxResult, error) {
 	resTxs, err := b.clientCtx.Client.TxSearch(b.ctx, query, false, nil, nil, "")
 	if err != nil {
 		return nil, err
 	}
 	if len(resTxs.Txs) == 0 {
-		return nil, errors.Errorf("ethereum tx not found for block %d index %d", height, index)
+		return nil, errors.New("ethereum tx not found")
 	}
-	return resTxs.Txs[0], nil
+	txResult := resTxs.Txs[0]
+	if !rpctypes.TxSuccessOrExceedsBlockGasLimit(&txResult.TxResult) {
+		return nil, errors.New("invalid ethereum tx")
+	}
+
+	var tx sdk.Tx
+	if txResult.TxResult.Code != 0 {
+		// it's only needed when the tx exceeds block gas limit
+		tx, err = b.clientCtx.TxConfig.TxDecoder()(txResult.Tx)
+		if err != nil {
+			return nil, fmt.Errorf("invalid ethereum tx")
+		}
+	}
+
+	return rpctypes.ParseTxIndexerResult(txResult, tx, txGetter)
 }

 // getTransactionByBlockAndIndex is the common code shared by `GetTransactionByBlockNumberAndIndex` and `GetTransactionByBlockHashAndIndex`.
@ -340,28 +347,18 @@ func (b *Backend) GetTransactionByBlockAndIndex(block *tmrpctypes.ResultBlock, i
 	}

 	var msg *evmtypes.MsgEthereumTx
-	// try /tx_search first
+	// find in tx indexer
 	res, err := b.GetTxByTxIndex(block.Block.Height, uint(idx))
 	if err == nil {
-		tx, err := b.clientCtx.TxConfig.TxDecoder()(res.Tx)
+		tx, err := b.clientCtx.TxConfig.TxDecoder()(block.Block.Txs[res.TxIndex])
 		if err != nil {
 			b.logger.Debug("invalid ethereum tx", "height", block.Block.Header, "index", idx)
 			return nil, nil
 		}

-		parsedTxs, err := rpctypes.ParseTxResult(&res.TxResult)
-		if err != nil {
-			return nil, fmt.Errorf("failed to parse tx events: %d, %v", idx, err)
-		}
-
-		parsedTx := parsedTxs.GetTxByTxIndex(int(idx))
-		if parsedTx == nil {
-			return nil, fmt.Errorf("ethereum tx not found in msgs: %d", idx)
-		}
-
 		var ok bool
 		// msgIndex is inferred from tx events, should be within bound.
-		msg, ok = tx.GetMsgs()[parsedTx.MsgIndex].(*evmtypes.MsgEthereumTx)
+		msg, ok = tx.GetMsgs()[res.MsgIndex].(*evmtypes.MsgEthereumTx)
 		if !ok {
 			b.logger.Debug("invalid ethereum tx", "height", block.Block.Header, "index", idx)
 			return nil, nil
--- a/rpc/backend/utils.go
+++ b/rpc/backend/utils.go
@ -23,10 +23,6 @@ import (
 	evmtypes "github.com/evmos/ethermint/x/evm/types"
 )

-// ExceedBlockGasLimitError defines the error message when tx execution exceeds the block gas limit.
-// The tx fee is deducted in ante handler, so it shouldn't be ignored in JSON-RPC API.
-const ExceedBlockGasLimitError = "out of gas in location: block gas meter; gasWanted:"
-
 type txGasAndReward struct {
 	gasUsed uint64
 	reward  *big.Int
@ -247,17 +243,6 @@ func ParseTxLogsFromEvent(event abci.Event) ([]*ethtypes.Log, error) {
 	return evmtypes.LogsToEthereum(logs), nil
 }

-// TxExceedBlockGasLimit returns true if the tx exceeds block gas limit.
-func TxExceedBlockGasLimit(res *abci.ResponseDeliverTx) bool {
-	return strings.Contains(res.Log, ExceedBlockGasLimitError)
-}
-
-// TxSuccessOrExceedsBlockGasLimit returnsrue if the transaction was successful
-// or if it failed with an ExceedBlockGasLimit error
-func TxSuccessOrExceedsBlockGasLimit(res *abci.ResponseDeliverTx) bool {
-	return res.Code == 0 || TxExceedBlockGasLimit(res)
-}
-
 // ShouldIgnoreGasUsed returns true if the gasUsed in result should be ignored
 // workaround for issue: https://github.com/cosmos/cosmos-sdk/issues/10832
 func ShouldIgnoreGasUsed(res *abci.ResponseDeliverTx) bool {
--- a/rpc/namespaces/ethereum/eth/api.go
+++ b/rpc/namespaces/ethereum/eth/api.go
@ -2,7 +2,6 @@ package eth

 import (
 	"context"
-	"fmt"
 	"math/big"

 	"github.com/ethereum/go-ethereum/signer/core/apitypes"
@ -453,23 +452,19 @@ func (e *PublicAPI) GetTransactionLogs(txHash common.Hash) ([]*ethtypes.Log, err
 		return nil, nil
 	}

-	if res.TxResult.Code != 0 {
+	if res.Failed {
 		// failed, return empty logs
 		return nil, nil
 	}

-	parsedTxs, err := rpctypes.ParseTxResult(&res.TxResult)
+	resBlockResult, err := e.backend.GetTendermintBlockResultByNumber(&res.Height)
 	if err != nil {
-		return nil, fmt.Errorf("failed to parse tx events: %s, %v", hexTx, err)
-	}
-
-	parsedTx := parsedTxs.GetTxByHash(txHash)
-	if parsedTx == nil {
-		return nil, fmt.Errorf("ethereum tx not found in msgs: %s", hexTx)
+		e.logger.Debug("block result not found", "number", res.Height, "error", err.Error())
+		return nil, nil
 	}

 	// parse tx logs from events
-	return parsedTx.ParseTxLogs()
+	return backend.TxLogsFromEvents(resBlockResult.TxsResults[res.TxIndex].Events, int(res.MsgIndex))
 }

 // SignTypedData signs EIP-712 conformant typed data
--- a/rpc/types/events.go
+++ b/rpc/types/events.go
@ -1,13 +1,15 @@
 package types

 import (
-	"encoding/json"
+	"fmt"
 	"strconv"

+	sdk "github.com/cosmos/cosmos-sdk/types"
 	"github.com/ethereum/go-ethereum/common"
-	ethtypes "github.com/ethereum/go-ethereum/core/types"
+	ethermint "github.com/evmos/ethermint/types"
 	evmtypes "github.com/evmos/ethermint/x/evm/types"
 	abci "github.com/tendermint/tendermint/abci/types"
+	tmrpctypes "github.com/tendermint/tendermint/rpc/core/types"
 )

 // EventFormat is the format version of the events.
@ -52,11 +54,9 @@ type ParsedTx struct {

 	Hash common.Hash
 	// -1 means uninitialized
-	EthTxIndex int64
+	EthTxIndex int32
 	GasUsed    uint64
 	Failed     bool
-	// unparsed tx log json strings
-	RawLogs [][]byte
 }

 // NewParsedTx initialize a ParsedTx
@ -64,20 +64,6 @@ func NewParsedTx(msgIndex int) ParsedTx {
 	return ParsedTx{MsgIndex: msgIndex, EthTxIndex: -1}
 }

-// ParseTxLogs decode the raw logs into ethereum format.
-func (p ParsedTx) ParseTxLogs() ([]*ethtypes.Log, error) {
-	logs := make([]*evmtypes.Log, 0, len(p.RawLogs))
-	for _, raw := range p.RawLogs {
-		var log evmtypes.Log
-		if err := json.Unmarshal(raw, &log); err != nil {
-			return nil, err
-		}
-
-		logs = append(logs, &log)
-	}
-	return evmtypes.LogsToEthereum(logs), nil
-}
-
 // ParsedTxs is the tx infos parsed from eth tx events.
 type ParsedTxs struct {
 	// one item per message
@ -88,7 +74,7 @@ type ParsedTxs struct {

 // ParseTxResult parse eth tx infos from cosmos-sdk events.
 // It supports two event formats, the formats are described in the comments of the format constants.
-func ParseTxResult(result *abci.ResponseDeliverTx) (*ParsedTxs, error) {
+func ParseTxResult(result *abci.ResponseDeliverTx, tx sdk.Tx) (*ParsedTxs, error) {
 	format := eventFormatUnknown
 	// the index of current ethereum_tx event in format 1 or the second part of format 2
 	eventIndex := -1
@ -97,8 +83,10 @@ func ParseTxResult(result *abci.ResponseDeliverTx) (*ParsedTxs, error) {
 		TxHashes: make(map[common.Hash]int),
 	}
 	for _, event := range result.Events {
-		switch event.Type {
-		case evmtypes.EventTypeEthereumTx:
+		if event.Type != evmtypes.EventTypeEthereumTx {
+			continue
+		}
+
 		if format == eventFormatUnknown {
 			// discover the format version by inspect the first ethereum_tx event.
 			if len(event.Attributes) > 2 {
@ -128,10 +116,6 @@ func ParseTxResult(result *abci.ResponseDeliverTx) (*ParsedTxs, error) {
 				}
 			}
 		}
-		case evmtypes.EventTypeTxLog:
-			// reuse the eventIndex set by previous ethereum_tx event
-			p.Txs[eventIndex].RawLogs = parseRawLogs(event.Attributes)
-		}
 	}

 	// some old versions miss some events, fill it with tx result
@ -139,9 +123,42 @@ func ParseTxResult(result *abci.ResponseDeliverTx) (*ParsedTxs, error) {
 		p.Txs[0].GasUsed = uint64(result.GasUsed)
 	}

+	// this could only happen if tx exceeds block gas limit
+	if result.Code != 0 && tx != nil {
+		for i := 0; i < len(p.Txs); i++ {
+			p.Txs[i].Failed = true
+
+			// replace gasUsed with gasLimit because that's what's actually deducted.
+			gasLimit := tx.GetMsgs()[i].(*evmtypes.MsgEthereumTx).GetGas()
+			p.Txs[i].GasUsed = gasLimit
+		}
+	}
 	return p, nil
 }

+// ParseTxIndexerResult parse tm tx result to a format compatible with the custom tx indexer.
+func ParseTxIndexerResult(txResult *tmrpctypes.ResultTx, tx sdk.Tx, getter func(*ParsedTxs) *ParsedTx) (*ethermint.TxResult, error) {
+	txs, err := ParseTxResult(&txResult.TxResult, tx)
+	if err != nil {
+		return nil, fmt.Errorf("failed to parse tx events: block %d, index %d, %v", txResult.Height, txResult.Index, err)
+	}
+
+	parsedTx := getter(txs)
+	if parsedTx == nil {
+		return nil, fmt.Errorf("ethereum tx not found in msgs: block %d, index %d", txResult.Height, txResult.Index)
+	}
+
+	return &ethermint.TxResult{
+		Height:            txResult.Height,
+		TxIndex:           txResult.Index,
+		MsgIndex:          uint32(parsedTx.MsgIndex),
+		EthTxIndex:        parsedTx.EthTxIndex,
+		Failed:            parsedTx.Failed,
+		GasUsed:           parsedTx.GasUsed,
+		CumulativeGasUsed: txs.AccumulativeGasUsed(parsedTx.MsgIndex),
+	}, nil
+}
+
 // newTx parse a new tx from events, called during parsing.
 func (p *ParsedTxs) newTx(attrs []abci.EventAttribute) error {
 	msgIndex := len(p.Txs)
@ -215,17 +232,17 @@ func fillTxAttribute(tx *ParsedTx, key []byte, value []byte) error {
 	case evmtypes.AttributeKeyEthereumTxHash:
 		tx.Hash = common.HexToHash(string(value))
 	case evmtypes.AttributeKeyTxIndex:
-		txIndex, err := strconv.ParseInt(string(value), 10, 64)
+		txIndex, err := strconv.ParseUint(string(value), 10, 31)
 		if err != nil {
 			return err
 		}
-		tx.EthTxIndex = txIndex
+		tx.EthTxIndex = int32(txIndex)
 	case evmtypes.AttributeKeyTxGasUsed:
-		gasUsed, err := strconv.ParseInt(string(value), 10, 64)
+		gasUsed, err := strconv.ParseUint(string(value), 10, 64)
 		if err != nil {
 			return err
 		}
-		tx.GasUsed = uint64(gasUsed)
+		tx.GasUsed = gasUsed
 	case evmtypes.AttributeKeyEthereumTxFailed:
 		tx.Failed = len(value) > 0
 	}
@ -240,10 +257,3 @@ func fillTxAttributes(tx *ParsedTx, attrs []abci.EventAttribute) error {
 	}
 	return nil
 }
-
-func parseRawLogs(attrs []abci.EventAttribute) (logs [][]byte) {
-	for _, attr := range attrs {
-		logs = append(logs, attr.Value)
-	}
-	return logs
-}
--- a/rpc/types/events_test.go
+++ b/rpc/types/events_test.go
@ -11,11 +11,6 @@ import (
 )

 func TestParseTxResult(t *testing.T) {
-	rawLogs := [][]byte{
-		[]byte("{\"address\":\"0xdcC261c03cD2f33eBea404318Cdc1D9f8b78e1AD\",\"topics\":[\"0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef\",\"0x000000000000000000000000569608516a81c0b1247310a3e0cd001046da0663\",\"0x0000000000000000000000002eea2c1ae0cdd2622381c2f9201b2a07c037b1f6\"],\"data\":\"AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAANB/GezJGOI=\",\"blockNumber\":1803258,\"transactionHash\":\"0xcf4354b55b9ac77436cf8b2f5c229ad3b3119b5196cd79ac5c6c382d9f7b0a71\",\"transactionIndex\":1,\"blockHash\":\"0xa69a510b0848180a094904ea9ae3f0ca2216029470c8e03e6941b402aba610d8\",\"logIndex\":5}"),
-		[]byte("{\"address\":\"0x569608516A81C0B1247310A3E0CD001046dA0663\",\"topics\":[\"0xe2403640ba68fed3a2f88b7557551d1993f84b99bb10ff833f0cf8db0c5e0486\",\"0x0000000000000000000000002eea2c1ae0cdd2622381c2f9201b2a07c037b1f6\"],\"data\":\"AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAANB/GezJGOI=\",\"blockNumber\":1803258,\"transactionHash\":\"0xcf4354b55b9ac77436cf8b2f5c229ad3b3119b5196cd79ac5c6c382d9f7b0a71\",\"transactionIndex\":1,\"blockHash\":\"0xa69a510b0848180a094904ea9ae3f0ca2216029470c8e03e6941b402aba610d8\",\"logIndex\":6}"),
-		[]byte("{\"address\":\"0x569608516A81C0B1247310A3E0CD001046dA0663\",\"topics\":[\"0xf279e6a1f5e320cca91135676d9cb6e44ca8a08c0b88342bcdb1144f6511b568\",\"0x0000000000000000000000002eea2c1ae0cdd2622381c2f9201b2a07c037b1f6\",\"0x0000000000000000000000000000000000000000000000000000000000000001\"],\"data\":\"AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA=\",\"blockNumber\":1803258,\"transactionHash\":\"0xcf4354b55b9ac77436cf8b2f5c229ad3b3119b5196cd79ac5c6c382d9f7b0a71\",\"transactionIndex\":1,\"blockHash\":\"0xa69a510b0848180a094904ea9ae3f0ca2216029470c8e03e6941b402aba610d8\",\"logIndex\":7}"),
-	}
 	address := "0x57f96e6B86CdeFdB3d412547816a82E3E0EbF9D2"
 	txHash := common.BigToHash(big.NewInt(1))
 	txHash2 := common.BigToHash(big.NewInt(2))
@ -46,11 +41,6 @@ func TestParseTxResult(t *testing.T) {
 						{Key: []byte("txHash"), Value: []byte("14A84ED06282645EFBF080E0B7ED80D8D8D6A36337668A12B5F229F81CDD3F57")},
 						{Key: []byte("recipient"), Value: []byte("0x775b87ef5D82ca211811C1a02CE0fE0CA3a455d7")},
 					}},
-					{Type: evmtypes.EventTypeTxLog, Attributes: []abci.EventAttribute{
-						{Key: []byte(evmtypes.AttributeKeyTxLog), Value: rawLogs[0]},
-						{Key: []byte(evmtypes.AttributeKeyTxLog), Value: rawLogs[1]},
-						{Key: []byte(evmtypes.AttributeKeyTxLog), Value: rawLogs[2]},
-					}},
 					{Type: "message", Attributes: []abci.EventAttribute{
 						{Key: []byte("action"), Value: []byte("/ethermint.evm.v1.MsgEthereumTx")},
 						{Key: []byte("key"), Value: []byte("ethm17xpfvakm2amg962yls6f84z3kell8c5lthdzgl")},
@ -76,7 +66,6 @@ func TestParseTxResult(t *testing.T) {
 					EthTxIndex: 10,
 					GasUsed:    21000,
 					Failed:     false,
-					RawLogs:    rawLogs,
 				},
 				{
 					MsgIndex:   1,
@ -84,7 +73,6 @@ func TestParseTxResult(t *testing.T) {
 					EthTxIndex: 11,
 					GasUsed:    21000,
 					Failed:     true,
-					RawLogs:    nil,
 				},
 			},
 		},
@ -113,11 +101,6 @@ func TestParseTxResult(t *testing.T) {
 						{Key: []byte("txHash"), Value: []byte("14A84ED06282645EFBF080E0B7ED80D8D8D6A36337668A12B5F229F81CDD3F57")},
 						{Key: []byte("recipient"), Value: []byte("0x775b87ef5D82ca211811C1a02CE0fE0CA3a455d7")},
 					}},
-					{Type: evmtypes.EventTypeTxLog, Attributes: []abci.EventAttribute{
-						{Key: []byte(evmtypes.AttributeKeyTxLog), Value: rawLogs[0]},
-						{Key: []byte(evmtypes.AttributeKeyTxLog), Value: rawLogs[1]},
-						{Key: []byte(evmtypes.AttributeKeyTxLog), Value: rawLogs[2]},
-					}},
 					{Type: "message", Attributes: []abci.EventAttribute{
 						{Key: []byte("action"), Value: []byte("/ethermint.evm.v1.MsgEthereumTx")},
 						{Key: []byte("key"), Value: []byte("ethm17xpfvakm2amg962yls6f84z3kell8c5lthdzgl")},
@ -133,7 +116,6 @@ func TestParseTxResult(t *testing.T) {
 					EthTxIndex: 0,
 					GasUsed:    21000,
 					Failed:     false,
-					RawLogs:    rawLogs,
 				},
 			},
 		},
@ -150,11 +132,6 @@ func TestParseTxResult(t *testing.T) {
 						{Key: []byte("txHash"), Value: []byte("14A84ED06282645EFBF080E0B7ED80D8D8D6A36337668A12B5F229F81CDD3F57")},
 						{Key: []byte("recipient"), Value: []byte("0x775b87ef5D82ca211811C1a02CE0fE0CA3a455d7")},
 					}},
-					{Type: evmtypes.EventTypeTxLog, Attributes: []abci.EventAttribute{
-						{Key: []byte(evmtypes.AttributeKeyTxLog), Value: rawLogs[0]},
-						{Key: []byte(evmtypes.AttributeKeyTxLog), Value: rawLogs[1]},
-						{Key: []byte(evmtypes.AttributeKeyTxLog), Value: rawLogs[2]},
-					}},
 					{Type: evmtypes.EventTypeEthereumTx, Attributes: []abci.EventAttribute{
 						{Key: []byte("ethereumTxHash"), Value: []byte(txHash2.Hex())},
 						{Key: []byte("txIndex"), Value: []byte("0x01")},
@ -182,11 +159,6 @@ func TestParseTxResult(t *testing.T) {
 						{Key: []byte("txHash"), Value: []byte("14A84ED06282645EFBF080E0B7ED80D8D8D6A36337668A12B5F229F81CDD3F57")},
 						{Key: []byte("recipient"), Value: []byte("0x775b87ef5D82ca211811C1a02CE0fE0CA3a455d7")},
 					}},
-					{Type: evmtypes.EventTypeTxLog, Attributes: []abci.EventAttribute{
-						{Key: []byte(evmtypes.AttributeKeyTxLog), Value: rawLogs[0]},
-						{Key: []byte(evmtypes.AttributeKeyTxLog), Value: rawLogs[1]},
-						{Key: []byte(evmtypes.AttributeKeyTxLog), Value: rawLogs[2]},
-					}},
 					{Type: evmtypes.EventTypeEthereumTx, Attributes: []abci.EventAttribute{
 						{Key: []byte("ethereumTxHash"), Value: []byte(txHash2.Hex())},
 						{Key: []byte("txIndex"), Value: []byte("10")},
@ -243,7 +215,7 @@ func TestParseTxResult(t *testing.T) {

 	for _, tc := range testCases {
 		t.Run(tc.name, func(t *testing.T) {
-			parsed, err := ParseTxResult(&tc.response)
+			parsed, err := ParseTxResult(&tc.response, nil)
 			if tc.expTxs == nil {
 				require.Error(t, err)
 			} else {
@ -252,8 +224,6 @@ func TestParseTxResult(t *testing.T) {
 					require.Equal(t, expTx, parsed.GetTxByMsgIndex(msgIndex))
 					require.Equal(t, expTx, parsed.GetTxByHash(expTx.Hash))
 					require.Equal(t, expTx, parsed.GetTxByTxIndex(int(expTx.EthTxIndex)))
-					_, err := expTx.ParseTxLogs()
-					require.NoError(t, err)
 				}
 				// non-exists tx hash
 				require.Nil(t, parsed.GetTxByHash(common.Hash{}))
@ -264,66 +234,3 @@ func TestParseTxResult(t *testing.T) {
 		})
 	}
 }
-
-func TestParseTxLogs(t *testing.T) {
-	rawLogs := [][]byte{
-		[]byte("{\"address\":\"0xdcC261c03cD2f33eBea404318Cdc1D9f8b78e1AD\",\"topics\":[\"0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef\",\"0x000000000000000000000000569608516a81c0b1247310a3e0cd001046da0663\",\"0x0000000000000000000000002eea2c1ae0cdd2622381c2f9201b2a07c037b1f6\"],\"data\":\"AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAANB/GezJGOI=\",\"blockNumber\":1803258,\"transactionHash\":\"0xcf4354b55b9ac77436cf8b2f5c229ad3b3119b5196cd79ac5c6c382d9f7b0a71\",\"transactionIndex\":1,\"blockHash\":\"0xa69a510b0848180a094904ea9ae3f0ca2216029470c8e03e6941b402aba610d8\",\"logIndex\":5}"),
-		[]byte("{\"address\":\"0x569608516A81C0B1247310A3E0CD001046dA0663\",\"topics\":[\"0xe2403640ba68fed3a2f88b7557551d1993f84b99bb10ff833f0cf8db0c5e0486\",\"0x0000000000000000000000002eea2c1ae0cdd2622381c2f9201b2a07c037b1f6\"],\"data\":\"AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAANB/GezJGOI=\",\"blockNumber\":1803258,\"transactionHash\":\"0xcf4354b55b9ac77436cf8b2f5c229ad3b3119b5196cd79ac5c6c382d9f7b0a71\",\"transactionIndex\":1,\"blockHash\":\"0xa69a510b0848180a094904ea9ae3f0ca2216029470c8e03e6941b402aba610d8\",\"logIndex\":6}"),
-		[]byte("{\"address\":\"0x569608516A81C0B1247310A3E0CD001046dA0663\",\"topics\":[\"0xf279e6a1f5e320cca91135676d9cb6e44ca8a08c0b88342bcdb1144f6511b568\",\"0x0000000000000000000000002eea2c1ae0cdd2622381c2f9201b2a07c037b1f6\",\"0x0000000000000000000000000000000000000000000000000000000000000001\"],\"data\":\"AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA=\",\"blockNumber\":1803258,\"transactionHash\":\"0xcf4354b55b9ac77436cf8b2f5c229ad3b3119b5196cd79ac5c6c382d9f7b0a71\",\"transactionIndex\":1,\"blockHash\":\"0xa69a510b0848180a094904ea9ae3f0ca2216029470c8e03e6941b402aba610d8\",\"logIndex\":7}"),
-	}
-	address := "0x57f96e6B86CdeFdB3d412547816a82E3E0EbF9D2"
-	txHash := common.BigToHash(big.NewInt(1))
-	txHash2 := common.BigToHash(big.NewInt(2))
-	response := abci.ResponseDeliverTx{
-		GasUsed: 21000,
-		Events: []abci.Event{
-			{Type: "coin_received", Attributes: []abci.EventAttribute{
-				{Key: []byte("receiver"), Value: []byte("ethm12luku6uxehhak02py4rcz65zu0swh7wjun6msa")},
-				{Key: []byte("amount"), Value: []byte("1252860basetcro")},
-			}},
-			{Type: "coin_spent", Attributes: []abci.EventAttribute{
-				{Key: []byte("spender"), Value: []byte("ethm17xpfvakm2amg962yls6f84z3kell8c5lthdzgl")},
-				{Key: []byte("amount"), Value: []byte("1252860basetcro")},
-			}},
-			{Type: evmtypes.EventTypeEthereumTx, Attributes: []abci.EventAttribute{
-				{Key: []byte("ethereumTxHash"), Value: []byte(txHash.Hex())},
-				{Key: []byte("txIndex"), Value: []byte("10")},
-				{Key: []byte("amount"), Value: []byte("1000")},
-				{Key: []byte("txGasUsed"), Value: []byte("21000")},
-				{Key: []byte("txHash"), Value: []byte("14A84ED06282645EFBF080E0B7ED80D8D8D6A36337668A12B5F229F81CDD3F57")},
-				{Key: []byte("recipient"), Value: []byte("0x775b87ef5D82ca211811C1a02CE0fE0CA3a455d7")},
-			}},
-			{Type: evmtypes.EventTypeTxLog, Attributes: []abci.EventAttribute{
-				{Key: []byte(evmtypes.AttributeKeyTxLog), Value: rawLogs[0]},
-				{Key: []byte(evmtypes.AttributeKeyTxLog), Value: rawLogs[1]},
-				{Key: []byte(evmtypes.AttributeKeyTxLog), Value: rawLogs[2]},
-			}},
-			{Type: "message", Attributes: []abci.EventAttribute{
-				{Key: []byte("action"), Value: []byte("/ethermint.evm.v1.MsgEthereumTx")},
-				{Key: []byte("key"), Value: []byte("ethm17xpfvakm2amg962yls6f84z3kell8c5lthdzgl")},
-				{Key: []byte("module"), Value: []byte("evm")},
-				{Key: []byte("sender"), Value: []byte(address)},
-			}},
-			{Type: evmtypes.EventTypeEthereumTx, Attributes: []abci.EventAttribute{
-				{Key: []byte("ethereumTxHash"), Value: []byte(txHash2.Hex())},
-				{Key: []byte("txIndex"), Value: []byte("11")},
-				{Key: []byte("amount"), Value: []byte("1000")},
-				{Key: []byte("txGasUsed"), Value: []byte("21000")},
-				{Key: []byte("txHash"), Value: []byte("14A84ED06282645EFBF080E0B7ED80D8D8D6A36337668A12B5F229F81CDD3F57")},
-				{Key: []byte("recipient"), Value: []byte("0x775b87ef5D82ca211811C1a02CE0fE0CA3a455d7")},
-				{Key: []byte("ethereumTxFailed"), Value: []byte("contract reverted")},
-			}},
-			{Type: evmtypes.EventTypeTxLog, Attributes: []abci.EventAttribute{}},
-		},
-	}
-	parsed, err := ParseTxResult(&response)
-	require.NoError(t, err)
-	tx1 := parsed.GetTxByMsgIndex(0)
-	txLogs1, err := tx1.ParseTxLogs()
-	require.NoError(t, err)
-	require.NotEmpty(t, txLogs1)
-
-	tx2 := parsed.GetTxByMsgIndex(1)
-	txLogs2, err := tx2.ParseTxLogs()
-	require.Empty(t, txLogs2)
-}
--- a/rpc/types/utils.go
+++ b/rpc/types/utils.go
@ -5,6 +5,7 @@ import (
 	"context"
 	"fmt"
 	"math/big"
+	"strings"

 	abci "github.com/tendermint/tendermint/abci/types"
 	tmtypes "github.com/tendermint/tendermint/types"
@ -22,6 +23,10 @@ import (
 	"github.com/ethereum/go-ethereum/params"
 )

+// ExceedBlockGasLimitError defines the error message when tx execution exceeds the block gas limit.
+// The tx fee is deducted in ante handler, so it shouldn't be ignored in JSON-RPC API.
+const ExceedBlockGasLimitError = "out of gas in location: block gas meter; gasWanted:"
+
 // RawTxToEthTx returns a evm MsgEthereum transaction from raw tx bytes.
 func RawTxToEthTx(clientCtx client.Context, txBz tmtypes.Tx) ([]*evmtypes.MsgEthereumTx, error) {
 	tx, err := clientCtx.TxConfig.TxDecoder()(txBz)
@ -243,3 +248,14 @@ func CheckTxFee(gasPrice *big.Int, gas uint64, cap float64) error {
 	}
 	return nil
 }
+
+// TxExceedBlockGasLimit returns true if the tx exceeds block gas limit.
+func TxExceedBlockGasLimit(res *abci.ResponseDeliverTx) bool {
+	return strings.Contains(res.Log, ExceedBlockGasLimitError)
+}
+
+// TxSuccessOrExceedsBlockGasLimit returnsrue if the transaction was successful
+// or if it failed with an ExceedBlockGasLimit error
+func TxSuccessOrExceedsBlockGasLimit(res *abci.ResponseDeliverTx) bool {
+	return res.Code == 0 || TxExceedBlockGasLimit(res)
+}
--- a/server/config/config.go
+++ b/server/config/config.go
@ -108,6 +108,8 @@ type JSONRPCConfig struct {
 	// MaxOpenConnections sets the maximum number of simultaneous connections
 	// for the server listener.
 	MaxOpenConnections int `mapstructure:"max-open-connections"`
+	// EnableIndexer defines if enable the custom indexer service.
+	EnableIndexer bool `mapstructure:"enable-indexer"`
 }

 // TLSConfig defines the certificate and matching private key for the server.
@ -208,6 +210,7 @@ func DefaultJSONRPCConfig() *JSONRPCConfig {
 		HTTPIdleTimeout:     DefaultHTTPIdleTimeout,
 		AllowUnprotectedTxs: DefaultAllowUnprotectedTxs,
 		MaxOpenConnections:  DefaultMaxOpenConnections,
+		EnableIndexer:       false,
 	}
 }

@ -312,6 +315,7 @@ func GetConfig(v *viper.Viper) Config {
 			HTTPTimeout:        v.GetDuration("json-rpc.http-timeout"),
 			HTTPIdleTimeout:    v.GetDuration("json-rpc.http-idle-timeout"),
 			MaxOpenConnections: v.GetInt("json-rpc.max-open-connections"),
+			EnableIndexer:      v.GetBool("json-rpc.enable-indexer"),
 		},
 		TLS: TLSConfig{
 			CertificatePath: v.GetString("tls.certificate-path"),
--- a/server/config/toml.go
+++ b/server/config/toml.go
@ -70,6 +70,9 @@ allow-unprotected-txs = {{ .JSONRPC.AllowUnprotectedTxs }}
 # for the server listener.
 max-open-connections = {{ .JSONRPC.MaxOpenConnections }}

+# EnableIndexer enables the custom transaction indexer for the EVM (ethereum transactions).
+enable-indexer = {{ .JSONRPC.EnableIndexer }}
+
 ###############################################################################
 ###                             TLS Configuration                           ###
 ###############################################################################
--- a/server/flags/flags.go
+++ b/server/flags/flags.go
@ -48,6 +48,7 @@ const (
 	JSONRPCHTTPIdleTimeout     = "json-rpc.http-idle-timeout"
 	JSONRPCAllowUnprotectedTxs = "json-rpc.allow-unprotected-txs"
 	JSONRPCMaxOpenConnections  = "json-rpc.max-open-connections"
+	JSONRPCEnableIndexer       = "json-rpc.enable-indexer"
 )

 // EVM flags
--- a/server/indexer_cmd.go
+++ b/server/indexer_cmd.go
@ -0,0 +1,112 @@
+package server
+
+import (
+	"fmt"
+
+	"github.com/spf13/cobra"
+
+	"github.com/cosmos/cosmos-sdk/client"
+	"github.com/cosmos/cosmos-sdk/server"
+	"github.com/evmos/ethermint/indexer"
+	tmnode "github.com/tendermint/tendermint/node"
+	sm "github.com/tendermint/tendermint/state"
+	tmstore "github.com/tendermint/tendermint/store"
+)
+
+func NewIndexTxCmd() *cobra.Command {
+	cmd := &cobra.Command{
+		Use:   "index-eth-tx [forward|backward]",
+		Short: "Index historical eth txs",
+		Long: `Index historical eth txs, it only support two traverse direction to avoid creating gaps in the indexer db if using arbitrary block ranges:
+		- backward: index the blocks from the first indexed block to the earliest block in the chain.
+		- forward: index the blocks from the latest indexed block to latest block in the chain.
+		`,
+		Args: cobra.ExactArgs(1),
+		RunE: func(cmd *cobra.Command, args []string) error {
+			serverCtx := server.GetServerContextFromCmd(cmd)
+			clientCtx, err := client.GetClientQueryContext(cmd)
+			if err != nil {
+				return err
+			}
+
+			direction := args[0]
+			if direction != "backward" && direction != "forward" {
+				return fmt.Errorf("unknown index direction, expect: backward|forward, got: %s", direction)
+			}
+
+			cfg := serverCtx.Config
+			home := cfg.RootDir
+			logger := serverCtx.Logger
+			idxDB, err := OpenIndexerDB(home, server.GetAppDBBackend(serverCtx.Viper))
+			if err != nil {
+				logger.Error("failed to open evm indexer DB", "error", err.Error())
+				return err
+			}
+			idxer := indexer.NewKVIndexer(idxDB, logger.With("module", "evmindex"), clientCtx)
+
+			// open local tendermint db, because the local rpc won't be available.
+			tmdb, err := tmnode.DefaultDBProvider(&tmnode.DBContext{ID: "blockstore", Config: cfg})
+			if err != nil {
+				return err
+			}
+			blockStore := tmstore.NewBlockStore(tmdb)
+
+			stateDB, err := tmnode.DefaultDBProvider(&tmnode.DBContext{ID: "state", Config: cfg})
+			if err != nil {
+				return err
+			}
+			stateStore := sm.NewStore(stateDB)
+
+			indexBlock := func(height int64) error {
+				blk := blockStore.LoadBlock(height)
+				if blk == nil {
+					return fmt.Errorf("block not found %d", height)
+				}
+				resBlk, err := stateStore.LoadABCIResponses(height)
+				if err != nil {
+					return err
+				}
+				if err := idxer.IndexBlock(blk, resBlk.DeliverTxs); err != nil {
+					return err
+				}
+				fmt.Println(height)
+				return nil
+			}
+
+			switch args[0] {
+			case "backward":
+				first, err := idxer.FirstIndexedBlock()
+				if err != nil {
+					return err
+				}
+				if first == -1 {
+					return fmt.Errorf("indexer db is empty")
+				}
+				for i := first - 1; i > 0; i-- {
+					if err := indexBlock(i); err != nil {
+						return err
+					}
+				}
+			case "forward":
+				latest, err := idxer.LastIndexedBlock()
+				if err != nil {
+					return err
+				}
+				if latest == -1 {
+					// start from genesis if empty
+					latest = 0
+				}
+				for i := latest + 1; i <= blockStore.Height(); i++ {
+					if err := indexBlock(i); err != nil {
+						return err
+					}
+				}
+			default:
+				return fmt.Errorf("unknown direction %s", args[0])
+			}
+
+			return nil
+		},
+	}
+	return cmd
+}
--- a/server/indexer_service.go
+++ b/server/indexer_service.go
@ -0,0 +1,109 @@
+package server
+
+import (
+	"context"
+	"time"
+
+	"github.com/tendermint/tendermint/libs/service"
+	rpcclient "github.com/tendermint/tendermint/rpc/client"
+	"github.com/tendermint/tendermint/types"
+
+	ethermint "github.com/evmos/ethermint/types"
+)
+
+const (
+	ServiceName = "EVMIndexerService"
+
+	NewBlockWaitTimeout = 60 * time.Second
+)
+
+// EVMIndexerService indexes transactions for json-rpc service.
+type EVMIndexerService struct {
+	service.BaseService
+
+	txIdxr ethermint.EVMTxIndexer
+	client rpcclient.Client
+}
+
+// NewEVMIndexerService returns a new service instance.
+func NewEVMIndexerService(
+	txIdxr ethermint.EVMTxIndexer,
+	client rpcclient.Client,
+) *EVMIndexerService {
+	is := &EVMIndexerService{txIdxr: txIdxr, client: client}
+	is.BaseService = *service.NewBaseService(nil, ServiceName, is)
+	return is
+}
+
+// OnStart implements service.Service by subscribing for new blocks
+// and indexing them by events.
+func (eis *EVMIndexerService) OnStart() error {
+	ctx := context.Background()
+	status, err := eis.client.Status(ctx)
+	if err != nil {
+		return err
+	}
+	latestBlock := status.SyncInfo.LatestBlockHeight
+	newBlockSignal := make(chan struct{}, 1)
+
+	// Use SubscribeUnbuffered here to ensure both subscriptions does not get
+	// canceled due to not pulling messages fast enough. Cause this might
+	// sometimes happen when there are no other subscribers.
+	blockHeadersChan, err := eis.client.Subscribe(
+		ctx,
+		ServiceName,
+		types.QueryForEvent(types.EventNewBlockHeader).String(),
+		0)
+	if err != nil {
+		return err
+	}
+
+	go func() {
+		for {
+			msg := <-blockHeadersChan
+			eventDataHeader := msg.Data.(types.EventDataNewBlockHeader)
+			if eventDataHeader.Header.Height > latestBlock {
+				latestBlock = eventDataHeader.Header.Height
+				// notify
+				select {
+				case newBlockSignal <- struct{}{}:
+				default:
+				}
+			}
+		}
+	}()
+
+	lastBlock, err := eis.txIdxr.LastIndexedBlock()
+	if err != nil {
+		return err
+	}
+	if lastBlock == -1 {
+		lastBlock = latestBlock
+	}
+	for {
+		if latestBlock <= lastBlock {
+			// nothing to index. wait for signal of new block
+			select {
+			case <-newBlockSignal:
+			case <-time.After(NewBlockWaitTimeout):
+			}
+			continue
+		}
+		for i := lastBlock + 1; i <= latestBlock; i++ {
+			block, err := eis.client.Block(ctx, &i)
+			if err != nil {
+				eis.Logger.Error("failed to fetch block", "height", i, "err", err)
+				break
+			}
+			blockResult, err := eis.client.BlockResults(ctx, &i)
+			if err != nil {
+				eis.Logger.Error("failed to fetch block result", "height", i, "err", err)
+				break
+			}
+			if err := eis.txIdxr.IndexBlock(block.Block, blockResult.TxsResults); err != nil {
+				eis.Logger.Error("failed to index block", "height", i, "err", err)
+			}
+			lastBlock = blockResult.Height
+		}
+	}
+}
--- a/server/json_rpc.go
+++ b/server/json_rpc.go
@ -15,10 +15,11 @@ import (
 	"github.com/evmos/ethermint/rpc"

 	"github.com/evmos/ethermint/server/config"
+	ethermint "github.com/evmos/ethermint/types"
 )

 // StartJSONRPC starts the JSON-RPC server
-func StartJSONRPC(ctx *server.Context, clientCtx client.Context, tmRPCAddr, tmEndpoint string, config *config.Config) (*http.Server, chan struct{}, error) {
+func StartJSONRPC(ctx *server.Context, clientCtx client.Context, tmRPCAddr, tmEndpoint string, config *config.Config, indexer ethermint.EVMTxIndexer) (*http.Server, chan struct{}, error) {
 	tmWsClient := ConnectTmWS(tmRPCAddr, tmEndpoint, ctx.Logger)

 	logger := ctx.Logger.With("module", "geth")
@ -39,7 +40,7 @@ func StartJSONRPC(ctx *server.Context, clientCtx client.Context, tmRPCAddr, tmEn
 	allowUnprotectedTxs := config.JSONRPC.AllowUnprotectedTxs
 	rpcAPIArr := config.JSONRPC.API

-	apis := rpc.GetRPCAPIs(ctx, clientCtx, tmWsClient, allowUnprotectedTxs, rpcAPIArr)
+	apis := rpc.GetRPCAPIs(ctx, clientCtx, tmWsClient, allowUnprotectedTxs, indexer, rpcAPIArr)

 	for _, api := range apis {
 		if err := rpcServer.RegisterName(api.Namespace, api.Service); err != nil {
--- a/server/start.go
+++ b/server/start.go
@ -40,9 +40,11 @@ import (
 	servergrpc "github.com/cosmos/cosmos-sdk/server/grpc"
 	"github.com/cosmos/cosmos-sdk/server/types"

+	"github.com/evmos/ethermint/indexer"
 	ethdebug "github.com/evmos/ethermint/rpc/namespaces/ethereum/debug"
 	"github.com/evmos/ethermint/server/config"
 	srvflags "github.com/evmos/ethermint/server/flags"
+	ethermint "github.com/evmos/ethermint/types"
 )

 // StartCmd runs the service passed in, either stand-alone or in-process with
@ -165,6 +167,7 @@ which accepts a path for the resulting pprof file.
 	cmd.Flags().Int32(srvflags.JSONRPCLogsCap, config.DefaultLogsCap, "Sets the max number of results can be returned from single `eth_getLogs` query")
 	cmd.Flags().Int32(srvflags.JSONRPCBlockRangeCap, config.DefaultBlockRangeCap, "Sets the max block range allowed for `eth_getLogs` query")
 	cmd.Flags().Int(srvflags.JSONRPCMaxOpenConnections, config.DefaultMaxOpenConnections, "Sets the maximum number of simultaneous connections for the server listener")
+	cmd.Flags().Bool(srvflags.JSONRPCEnableIndexer, false, "Enable the custom tx indexer for json-rpc")

 	cmd.Flags().String(srvflags.EVMTracer, config.DefaultEVMTracer, "the EVM tracer type to collect execution traces from the EVM transaction execution (json|struct|access_list|markdown)")
 	cmd.Flags().Uint64(srvflags.EVMMaxTxGasWanted, config.DefaultMaxTxGasWanted, "the gas wanted for each eth tx returned in ante handler in check tx mode")
@ -323,13 +326,39 @@ func startInProcess(ctx *server.Context, clientCtx client.Context, appCreator ty
 	// Add the tx service to the gRPC router. We only need to register this
 	// service if API or gRPC or JSONRPC is enabled, and avoid doing so in the general
 	// case, because it spawns a new local tendermint RPC client.
-	if config.API.Enable || config.GRPC.Enable || config.JSONRPC.Enable {
+	if config.API.Enable || config.GRPC.Enable || config.JSONRPC.Enable || config.JSONRPC.EnableIndexer {
 		clientCtx = clientCtx.WithClient(local.New(tmNode))

 		app.RegisterTxService(clientCtx)
 		app.RegisterTendermintService(clientCtx)
 	}

+	var idxer ethermint.EVMTxIndexer
+	if config.JSONRPC.EnableIndexer {
+		idxDB, err := OpenIndexerDB(home, server.GetAppDBBackend(ctx.Viper))
+		if err != nil {
+			logger.Error("failed to open evm indexer DB", "error", err.Error())
+			return err
+		}
+		idxLogger := ctx.Logger.With("module", "evmindex")
+		idxer = indexer.NewKVIndexer(idxDB, idxLogger, clientCtx)
+		indexerService := NewEVMIndexerService(idxer, clientCtx.Client)
+		indexerService.SetLogger(idxLogger)
+
+		errCh := make(chan error)
+		go func() {
+			if err := indexerService.Start(); err != nil {
+				errCh <- err
+			}
+		}()
+
+		select {
+		case err := <-errCh:
+			return err
+		case <-time.After(types.ServerStartTime): // assume server started successfully
+		}
+	}
+
 	var apiSrv *api.Server
 	if config.API.Enable {
 		genDoc, err := genDocProvider()
@ -427,7 +456,7 @@ func startInProcess(ctx *server.Context, clientCtx client.Context, appCreator ty

 		tmEndpoint := "/websocket"
 		tmRPCAddr := cfg.RPC.ListenAddress
-		httpSrv, httpSrvDone, err = StartJSONRPC(ctx, clientCtx, tmRPCAddr, tmEndpoint, &config)
+		httpSrv, httpSrvDone, err = StartJSONRPC(ctx, clientCtx, tmRPCAddr, tmEndpoint, &config, idxer)
 		if err != nil {
 			return err
 		}
@ -482,6 +511,12 @@ func openDB(rootDir string, backendType dbm.BackendType) (dbm.DB, error) {
 	return dbm.NewDB("application", backendType, dataDir)
 }

+// OpenIndexerDB opens the custom eth indexer db, using the same db backend as the main app
+func OpenIndexerDB(rootDir string, backendType dbm.BackendType) (dbm.DB, error) {
+	dataDir := filepath.Join(rootDir, "data")
+	return dbm.NewDB("evmindexer", backendType, dataDir)
+}
+
 func openTraceWriter(traceWriterFile string) (w io.Writer, err error) {
 	if traceWriterFile == "" {
 		return
--- a/server/util.go
+++ b/server/util.go
@ -45,6 +45,9 @@ func AddCommands(rootCmd *cobra.Command, defaultNodeHome string, appCreator type
 		sdkserver.ExportCmd(appExport, defaultNodeHome),
 		version.NewVersionCommand(),
 		sdkserver.NewRollbackCmd(defaultNodeHome),
+
+		// custom tx indexer command
+		NewIndexTxCmd(),
 	)
 }

--- a/tests/integration_tests/configs/enable-indexer.jsonnet
+++ b/tests/integration_tests/configs/enable-indexer.jsonnet
@ -0,0 +1,20 @@
+local config = import 'default.jsonnet';
+
+config {
+  'ethermint_9000-1'+: {
+    config+: {
+      tx_index+: {
+        indexer: 'null',
+      },
+    },
+    'app-config'+: {
+      pruning: 'everything',
+      'state-sync'+: {
+        'snapshot-interval': 0,
+      },
+      'json-rpc'+: {
+        'enable-indexer': true,
+      },
+    },
+  },
+}
--- a/tests/integration_tests/conftest.py
+++ b/tests/integration_tests/conftest.py
@ -1,6 +1,8 @@
+from pathlib import Path
+
 import pytest

-from .network import setup_ethermint, setup_geth
+from .network import setup_custom_ethermint, setup_ethermint, setup_geth


@pytest.fixture(scope="session")
@ -9,14 +11,24 @@ def ethermint(tmp_path_factory):
    yield from setup_ethermint(path, 26650)


+@pytest.fixture(scope="session")
+def ethermint_indexer(tmp_path_factory):
+    path = tmp_path_factory.mktemp("indexer")
+    yield from setup_custom_ethermint(
+        path, 26660, Path(__file__).parent / "configs/enable-indexer.jsonnet"
+    )
+
+
@pytest.fixture(scope="session")
 def geth(tmp_path_factory):
    path = tmp_path_factory.mktemp("geth")
    yield from setup_geth(path, 8545)


-@pytest.fixture(scope="session", params=["ethermint", "geth", "ethermint-ws"])
-def cluster(request, ethermint, geth):
+@pytest.fixture(
+    scope="session", params=["ethermint", "geth", "ethermint-ws", "enable-indexer"]
+)
+def cluster(request, ethermint, ethermint_indexer, geth):
    """
    run on both ethermint and geth
    """
@ -29,5 +41,7 @@ def cluster(request, ethermint, geth):
        ethermint_ws = ethermint.copy()
        ethermint_ws.use_websocket()
        yield ethermint_ws
+    elif provider == "enable-indexer":
+        yield ethermint_indexer
    else:
        raise NotImplementedError
--- a/testutil/network/util.go
+++ b/testutil/network/util.go
@ -131,7 +131,7 @@ func startInProcess(cfg Config, val *Validator) error {
 		tmEndpoint := "/websocket"
 		tmRPCAddr := val.RPCAddress

-		val.jsonrpc, val.jsonrpcDone, err = server.StartJSONRPC(val.Ctx, val.ClientCtx, tmRPCAddr, tmEndpoint, val.AppConfig)
+		val.jsonrpc, val.jsonrpcDone, err = server.StartJSONRPC(val.Ctx, val.ClientCtx, tmRPCAddr, tmEndpoint, val.AppConfig, nil)
 		if err != nil {
 			return err
 		}
--- a/types/indexer.go
+++ b/types/indexer.go
@ -0,0 +1,19 @@
+package types
+
+import (
+	"github.com/ethereum/go-ethereum/common"
+	abci "github.com/tendermint/tendermint/abci/types"
+	tmtypes "github.com/tendermint/tendermint/types"
+)
+
+// EVMTxIndexer defines the interface of custom eth tx indexer.
+type EVMTxIndexer interface {
+	// LastIndexedBlock returns -1 if indexer db is empty
+	LastIndexedBlock() (int64, error)
+	IndexBlock(*tmtypes.Block, []*abci.ResponseDeliverTx) error
+
+	// GetByTxHash returns nil if tx not found.
+	GetByTxHash(common.Hash) (*TxResult, error)
+	// GetByBlockAndIndex returns nil if tx not found.
+	GetByBlockAndIndex(int64, int32) (*TxResult, error)
+}
--- a/types/indexer.pb.go
+++ b/types/indexer.pb.go
@ -0,0 +1,485 @@
+// Code generated by protoc-gen-gogo. DO NOT EDIT.
+// source: ethermint/types/v1/indexer.proto
+
+package types
+
+import (
+	fmt "fmt"
+	_ "github.com/gogo/protobuf/gogoproto"
+	proto "github.com/gogo/protobuf/proto"
+	io "io"
+	math "math"
+	math_bits "math/bits"
+)
+
+// Reference imports to suppress errors if they are not otherwise used.
+var _ = proto.Marshal
+var _ = fmt.Errorf
+var _ = math.Inf
+
+// This is a compile-time assertion to ensure that this generated file
+// is compatible with the proto package it is being compiled against.
+// A compilation error at this line likely means your copy of the
+// proto package needs to be updated.
+const _ = proto.GoGoProtoPackageIsVersion3 // please upgrade the proto package
+
+// TxResult is the value stored in eth tx indexer
+type TxResult struct {
+	// the block height
+	Height int64 `protobuf:"varint,1,opt,name=height,proto3" json:"height,omitempty"`
+	// cosmos tx index
+	TxIndex uint32 `protobuf:"varint,2,opt,name=tx_index,json=txIndex,proto3" json:"tx_index,omitempty"`
+	// the msg index in a batch tx
+	MsgIndex uint32 `protobuf:"varint,3,opt,name=msg_index,json=msgIndex,proto3" json:"msg_index,omitempty"`
+	// eth tx index, the index in the list of valid eth tx in the block,
+	// aka. the transaction list returned by eth_getBlock api.
+	EthTxIndex int32 `protobuf:"varint,4,opt,name=eth_tx_index,json=ethTxIndex,proto3" json:"eth_tx_index,omitempty"`
+	// if the eth tx is failed
+	Failed bool `protobuf:"varint,5,opt,name=failed,proto3" json:"failed,omitempty"`
+	// gas used by tx, if exceeds block gas limit,
+	// it's set to gas limit which is what's actually deducted by ante handler.
+	GasUsed uint64 `protobuf:"varint,6,opt,name=gas_used,json=gasUsed,proto3" json:"gas_used,omitempty"`
+	// the cumulative gas used within current batch tx
+	CumulativeGasUsed uint64 `protobuf:"varint,7,opt,name=cumulative_gas_used,json=cumulativeGasUsed,proto3" json:"cumulative_gas_used,omitempty"`
+}
+
+func (m *TxResult) Reset()         { *m = TxResult{} }
+func (m *TxResult) String() string { return proto.CompactTextString(m) }
+func (*TxResult) ProtoMessage()    {}
+func (*TxResult) Descriptor() ([]byte, []int) {
+	return fileDescriptor_1197e10a8be8ed28, []int{0}
+}
+func (m *TxResult) XXX_Unmarshal(b []byte) error {
+	return m.Unmarshal(b)
+}
+func (m *TxResult) XXX_Marshal(b []byte, deterministic bool) ([]byte, error) {
+	if deterministic {
+		return xxx_messageInfo_TxResult.Marshal(b, m, deterministic)
+	} else {
+		b = b[:cap(b)]
+		n, err := m.MarshalToSizedBuffer(b)
+		if err != nil {
+			return nil, err
+		}
+		return b[:n], nil
+	}
+}
+func (m *TxResult) XXX_Merge(src proto.Message) {
+	xxx_messageInfo_TxResult.Merge(m, src)
+}
+func (m *TxResult) XXX_Size() int {
+	return m.Size()
+}
+func (m *TxResult) XXX_DiscardUnknown() {
+	xxx_messageInfo_TxResult.DiscardUnknown(m)
+}
+
+var xxx_messageInfo_TxResult proto.InternalMessageInfo
+
+func init() {
+	proto.RegisterType((*TxResult)(nil), "ethermint.types.v1.TxResult")
+}
+
+func init() { proto.RegisterFile("ethermint/types/v1/indexer.proto", fileDescriptor_1197e10a8be8ed28) }
+
+var fileDescriptor_1197e10a8be8ed28 = []byte{
+	// 295 bytes of a gzipped FileDescriptorProto
+	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xff, 0x5c, 0x90, 0x31, 0x4b, 0xc3, 0x40,
+	0x18, 0x86, 0x73, 0xb6, 0x4d, 0xe3, 0xa1, 0x83, 0x51, 0x4a, 0x54, 0x88, 0x87, 0x53, 0xa6, 0x84,
+	0xe2, 0xd6, 0xd1, 0x45, 0x5c, 0x8f, 0xba, 0xb8, 0x84, 0xb4, 0xf9, 0xbc, 0x3b, 0xe8, 0xf5, 0x4a,
+	0xef, 0x4b, 0x88, 0xff, 0xc0, 0xd1, 0x9f, 0xe0, 0xcf, 0x71, 0xec, 0xe8, 0x28, 0x2d, 0xfe, 0x0f,
+	0xe9, 0x35, 0x44, 0x70, 0xfb, 0x5e, 0x9e, 0xe7, 0xe3, 0x85, 0x97, 0x32, 0x40, 0x09, 0x6b, 0xad,
+	0x96, 0x98, 0xe1, 0xeb, 0x0a, 0x6c, 0x56, 0x8f, 0x33, 0xb5, 0x2c, 0xa1, 0x81, 0x75, 0xba, 0x5a,
+	0x1b, 0x34, 0x61, 0xd8, 0x19, 0xa9, 0x33, 0xd2, 0x7a, 0x7c, 0x75, 0x21, 0x8c, 0x30, 0x0e, 0x67,
+	0xfb, 0xeb, 0x60, 0xde, 0xfe, 0x10, 0x1a, 0x4c, 0x1b, 0x0e, 0xb6, 0x5a, 0x60, 0x38, 0xa2, 0xbe,
+	0x04, 0x25, 0x24, 0x46, 0x84, 0x91, 0xa4, 0xc7, 0xdb, 0x14, 0x5e, 0xd2, 0x00, 0x9b, 0xdc, 0x55,
+	0x44, 0x47, 0x8c, 0x24, 0xa7, 0x7c, 0x88, 0xcd, 0xe3, 0x3e, 0x86, 0xd7, 0xf4, 0x58, 0x5b, 0xd1,
+	0xb2, 0x9e, 0x63, 0x81, 0xb6, 0xe2, 0x00, 0x19, 0x3d, 0x01, 0x94, 0x79, 0xf7, 0xdb, 0x67, 0x24,
+	0x19, 0x70, 0x0a, 0x28, 0xa7, 0xed, 0xfb, 0x88, 0xfa, 0x2f, 0x85, 0x5a, 0x40, 0x19, 0x0d, 0x18,
+	0x49, 0x02, 0xde, 0xa6, 0x7d, 0xa3, 0x28, 0x6c, 0x5e, 0x59, 0x28, 0x23, 0x9f, 0x91, 0xa4, 0xcf,
+	0x87, 0xa2, 0xb0, 0x4f, 0x16, 0xca, 0x30, 0xa5, 0xe7, 0xf3, 0x4a, 0x57, 0x8b, 0x02, 0x55, 0x0d,
+	0x79, 0x67, 0x0d, 0x9d, 0x75, 0xf6, 0x87, 0x1e, 0x0e, 0xfe, 0xa4, 0xff, 0xf6, 0x71, 0xe3, 0xdd,
+	0x4f, 0x3e, 0xb7, 0x31, 0xd9, 0x6c, 0x63, 0xf2, 0xbd, 0x8d, 0xc9, 0xfb, 0x2e, 0xf6, 0x36, 0xbb,
+	0xd8, 0xfb, 0xda, 0xc5, 0xde, 0x33, 0x13, 0x0a, 0x65, 0x35, 0x4b, 0xe7, 0x46, 0x67, 0x50, 0x6b,
+	0x63, 0xb3, 0x7f, 0xf3, 0xce, 0x7c, 0x37, 0xd5, 0xdd, 0x6f, 0x00, 0x00, 0x00, 0xff, 0xff, 0xc1,
+	0x34, 0xa8, 0x0b, 0x78, 0x01, 0x00, 0x00,
+}
+
+func (m *TxResult) Marshal() (dAtA []byte, err error) {
+	size := m.Size()
+	dAtA = make([]byte, size)
+	n, err := m.MarshalToSizedBuffer(dAtA[:size])
+	if err != nil {
+		return nil, err
+	}
+	return dAtA[:n], nil
+}
+
+func (m *TxResult) MarshalTo(dAtA []byte) (int, error) {
+	size := m.Size()
+	return m.MarshalToSizedBuffer(dAtA[:size])
+}
+
+func (m *TxResult) MarshalToSizedBuffer(dAtA []byte) (int, error) {
+	i := len(dAtA)
+	_ = i
+	var l int
+	_ = l
+	if m.CumulativeGasUsed != 0 {
+		i = encodeVarintIndexer(dAtA, i, uint64(m.CumulativeGasUsed))
+		i--
+		dAtA[i] = 0x38
+	}
+	if m.GasUsed != 0 {
+		i = encodeVarintIndexer(dAtA, i, uint64(m.GasUsed))
+		i--
+		dAtA[i] = 0x30
+	}
+	if m.Failed {
+		i--
+		if m.Failed {
+			dAtA[i] = 1
+		} else {
+			dAtA[i] = 0
+		}
+		i--
+		dAtA[i] = 0x28
+	}
+	if m.EthTxIndex != 0 {
+		i = encodeVarintIndexer(dAtA, i, uint64(m.EthTxIndex))
+		i--
+		dAtA[i] = 0x20
+	}
+	if m.MsgIndex != 0 {
+		i = encodeVarintIndexer(dAtA, i, uint64(m.MsgIndex))
+		i--
+		dAtA[i] = 0x18
+	}
+	if m.TxIndex != 0 {
+		i = encodeVarintIndexer(dAtA, i, uint64(m.TxIndex))
+		i--
+		dAtA[i] = 0x10
+	}
+	if m.Height != 0 {
+		i = encodeVarintIndexer(dAtA, i, uint64(m.Height))
+		i--
+		dAtA[i] = 0x8
+	}
+	return len(dAtA) - i, nil
+}
+
+func encodeVarintIndexer(dAtA []byte, offset int, v uint64) int {
+	offset -= sovIndexer(v)
+	base := offset
+	for v >= 1<<7 {
+		dAtA[offset] = uint8(v&0x7f | 0x80)
+		v >>= 7
+		offset++
+	}
+	dAtA[offset] = uint8(v)
+	return base
+}
+func (m *TxResult) Size() (n int) {
+	if m == nil {
+		return 0
+	}
+	var l int
+	_ = l
+	if m.Height != 0 {
+		n += 1 + sovIndexer(uint64(m.Height))
+	}
+	if m.TxIndex != 0 {
+		n += 1 + sovIndexer(uint64(m.TxIndex))
+	}
+	if m.MsgIndex != 0 {
+		n += 1 + sovIndexer(uint64(m.MsgIndex))
+	}
+	if m.EthTxIndex != 0 {
+		n += 1 + sovIndexer(uint64(m.EthTxIndex))
+	}
+	if m.Failed {
+		n += 2
+	}
+	if m.GasUsed != 0 {
+		n += 1 + sovIndexer(uint64(m.GasUsed))
+	}
+	if m.CumulativeGasUsed != 0 {
+		n += 1 + sovIndexer(uint64(m.CumulativeGasUsed))
+	}
+	return n
+}
+
+func sovIndexer(x uint64) (n int) {
+	return (math_bits.Len64(x|1) + 6) / 7
+}
+func sozIndexer(x uint64) (n int) {
+	return sovIndexer(uint64((x << 1) ^ uint64((int64(x) >> 63))))
+}
+func (m *TxResult) Unmarshal(dAtA []byte) error {
+	l := len(dAtA)
+	iNdEx := 0
+	for iNdEx < l {
+		preIndex := iNdEx
+		var wire uint64
+		for shift := uint(0); ; shift += 7 {
+			if shift >= 64 {
+				return ErrIntOverflowIndexer
+			}
+			if iNdEx >= l {
+				return io.ErrUnexpectedEOF
+			}
+			b := dAtA[iNdEx]
+			iNdEx++
+			wire |= uint64(b&0x7F) << shift
+			if b < 0x80 {
+				break
+			}
+		}
+		fieldNum := int32(wire >> 3)
+		wireType := int(wire & 0x7)
+		if wireType == 4 {
+			return fmt.Errorf("proto: TxResult: wiretype end group for non-group")
+		}
+		if fieldNum <= 0 {
+			return fmt.Errorf("proto: TxResult: illegal tag %d (wire type %d)", fieldNum, wire)
+		}
+		switch fieldNum {
+		case 1:
+			if wireType != 0 {
+				return fmt.Errorf("proto: wrong wireType = %d for field Height", wireType)
+			}
+			m.Height = 0
+			for shift := uint(0); ; shift += 7 {
+				if shift >= 64 {
+					return ErrIntOverflowIndexer
+				}
+				if iNdEx >= l {
+					return io.ErrUnexpectedEOF
+				}
+				b := dAtA[iNdEx]
+				iNdEx++
+				m.Height |= int64(b&0x7F) << shift
+				if b < 0x80 {
+					break
+				}
+			}
+		case 2:
+			if wireType != 0 {
+				return fmt.Errorf("proto: wrong wireType = %d for field TxIndex", wireType)
+			}
+			m.TxIndex = 0
+			for shift := uint(0); ; shift += 7 {
+				if shift >= 64 {
+					return ErrIntOverflowIndexer
+				}
+				if iNdEx >= l {
+					return io.ErrUnexpectedEOF
+				}
+				b := dAtA[iNdEx]
+				iNdEx++
+				m.TxIndex |= uint32(b&0x7F) << shift
+				if b < 0x80 {
+					break
+				}
+			}
+		case 3:
+			if wireType != 0 {
+				return fmt.Errorf("proto: wrong wireType = %d for field MsgIndex", wireType)
+			}
+			m.MsgIndex = 0
+			for shift := uint(0); ; shift += 7 {
+				if shift >= 64 {
+					return ErrIntOverflowIndexer
+				}
+				if iNdEx >= l {
+					return io.ErrUnexpectedEOF
+				}
+				b := dAtA[iNdEx]
+				iNdEx++
+				m.MsgIndex |= uint32(b&0x7F) << shift
+				if b < 0x80 {
+					break
+				}
+			}
+		case 4:
+			if wireType != 0 {
+				return fmt.Errorf("proto: wrong wireType = %d for field EthTxIndex", wireType)
+			}
+			m.EthTxIndex = 0
+			for shift := uint(0); ; shift += 7 {
+				if shift >= 64 {
+					return ErrIntOverflowIndexer
+				}
+				if iNdEx >= l {
+					return io.ErrUnexpectedEOF
+				}
+				b := dAtA[iNdEx]
+				iNdEx++
+				m.EthTxIndex |= int32(b&0x7F) << shift
+				if b < 0x80 {
+					break
+				}
+			}
+		case 5:
+			if wireType != 0 {
+				return fmt.Errorf("proto: wrong wireType = %d for field Failed", wireType)
+			}
+			var v int
+			for shift := uint(0); ; shift += 7 {
+				if shift >= 64 {
+					return ErrIntOverflowIndexer
+				}
+				if iNdEx >= l {
+					return io.ErrUnexpectedEOF
+				}
+				b := dAtA[iNdEx]
+				iNdEx++
+				v |= int(b&0x7F) << shift
+				if b < 0x80 {
+					break
+				}
+			}
+			m.Failed = bool(v != 0)
+		case 6:
+			if wireType != 0 {
+				return fmt.Errorf("proto: wrong wireType = %d for field GasUsed", wireType)
+			}
+			m.GasUsed = 0
+			for shift := uint(0); ; shift += 7 {
+				if shift >= 64 {
+					return ErrIntOverflowIndexer
+				}
+				if iNdEx >= l {
+					return io.ErrUnexpectedEOF
+				}
+				b := dAtA[iNdEx]
+				iNdEx++
+				m.GasUsed |= uint64(b&0x7F) << shift
+				if b < 0x80 {
+					break
+				}
+			}
+		case 7:
+			if wireType != 0 {
+				return fmt.Errorf("proto: wrong wireType = %d for field CumulativeGasUsed", wireType)
+			}
+			m.CumulativeGasUsed = 0
+			for shift := uint(0); ; shift += 7 {
+				if shift >= 64 {
+					return ErrIntOverflowIndexer
+				}
+				if iNdEx >= l {
+					return io.ErrUnexpectedEOF
+				}
+				b := dAtA[iNdEx]
+				iNdEx++
+				m.CumulativeGasUsed |= uint64(b&0x7F) << shift
+				if b < 0x80 {
+					break
+				}
+			}
+		default:
+			iNdEx = preIndex
+			skippy, err := skipIndexer(dAtA[iNdEx:])
+			if err != nil {
+				return err
+			}
+			if (skippy < 0) || (iNdEx+skippy) < 0 {
+				return ErrInvalidLengthIndexer
+			}
+			if (iNdEx + skippy) > l {
+				return io.ErrUnexpectedEOF
+			}
+			iNdEx += skippy
+		}
+	}
+
+	if iNdEx > l {
+		return io.ErrUnexpectedEOF
+	}
+	return nil
+}
+func skipIndexer(dAtA []byte) (n int, err error) {
+	l := len(dAtA)
+	iNdEx := 0
+	depth := 0
+	for iNdEx < l {
+		var wire uint64
+		for shift := uint(0); ; shift += 7 {
+			if shift >= 64 {
+				return 0, ErrIntOverflowIndexer
+			}
+			if iNdEx >= l {
+				return 0, io.ErrUnexpectedEOF
+			}
+			b := dAtA[iNdEx]
+			iNdEx++
+			wire |= (uint64(b) & 0x7F) << shift
+			if b < 0x80 {
+				break
+			}
+		}
+		wireType := int(wire & 0x7)
+		switch wireType {
+		case 0:
+			for shift := uint(0); ; shift += 7 {
+				if shift >= 64 {
+					return 0, ErrIntOverflowIndexer
+				}
+				if iNdEx >= l {
+					return 0, io.ErrUnexpectedEOF
+				}
+				iNdEx++
+				if dAtA[iNdEx-1] < 0x80 {
+					break
+				}
+			}
+		case 1:
+			iNdEx += 8
+		case 2:
+			var length int
+			for shift := uint(0); ; shift += 7 {
+				if shift >= 64 {
+					return 0, ErrIntOverflowIndexer
+				}
+				if iNdEx >= l {
+					return 0, io.ErrUnexpectedEOF
+				}
+				b := dAtA[iNdEx]
+				iNdEx++
+				length |= (int(b) & 0x7F) << shift
+				if b < 0x80 {
+					break
+				}
+			}
+			if length < 0 {
+				return 0, ErrInvalidLengthIndexer
+			}
+			iNdEx += length
+		case 3:
+			depth++
+		case 4:
+			if depth == 0 {
+				return 0, ErrUnexpectedEndOfGroupIndexer
+			}
+			depth--
+		case 5:
+			iNdEx += 4
+		default:
+			return 0, fmt.Errorf("proto: illegal wireType %d", wireType)
+		}
+		if iNdEx < 0 {
+			return 0, ErrInvalidLengthIndexer
+		}
+		if depth == 0 {
+			return iNdEx, nil
+		}
+	}
+	return 0, io.ErrUnexpectedEOF
+}
+
+var (
+	ErrInvalidLengthIndexer        = fmt.Errorf("proto: negative length found during unmarshaling")
+	ErrIntOverflowIndexer          = fmt.Errorf("proto: integer overflow")
+	ErrUnexpectedEndOfGroupIndexer = fmt.Errorf("proto: unexpected end of group")
+)