rpc: refactor rpc packages and backend to support cosmos namespace (#1070)

* rpc: refactor rpc packages and backend to support cosmos namespace

* changelog

* typo

CHANGELOG.md

@@ -38,6 +38,15 @@ Ref: https://keepachangelog.com/en/1.0.0/
 
 ## Unreleased
 
+### API Breaking
+
+* (rpc) [tharsis#1070](https://github.com/tharsis/ethermint/pull/1070) Refactor `rpc/` package:
+  * `Backend` interface is now `BackendI`, which implements `EVMBackend` (for Ethereum namespaces) and `CosmosBackend` (for Cosmos namespaces)
+  * Previous `EVMBackend` type is now `Backend`, which is the concrete implementation of `BackendI`
+  * Move `rpc/ethereum/types` -> `rpc/types`
+  * Move `rpc/ethereum/backend` -> `rpc/backend`
+  * Move `rpc/ethereum/namespaces` -> `rpc/namespaces/ethereum`
+
 ### Bug Fixes
 
 * (rpc) [tharsis#1059](https://github.com/tharsis/ethermint/pull/1059) Remove unnecessary event filtering logic on the `eth_baseFee` JSON-RPC endpoint.

rpc/apis.go

@@ -10,22 +10,28 @@ import (
 
 	"github.com/ethereum/go-ethereum/rpc"
 
-	"github.com/tharsis/ethermint/rpc/ethereum/backend"
-	"github.com/tharsis/ethermint/rpc/ethereum/namespaces/debug"
-	"github.com/tharsis/ethermint/rpc/ethereum/namespaces/eth"
-	"github.com/tharsis/ethermint/rpc/ethereum/namespaces/eth/filters"
-	"github.com/tharsis/ethermint/rpc/ethereum/namespaces/miner"
-	"github.com/tharsis/ethermint/rpc/ethereum/namespaces/net"
-	"github.com/tharsis/ethermint/rpc/ethereum/namespaces/personal"
-	"github.com/tharsis/ethermint/rpc/ethereum/namespaces/txpool"
-	"github.com/tharsis/ethermint/rpc/ethereum/namespaces/web3"
-	"github.com/tharsis/ethermint/rpc/ethereum/types"
+	"github.com/tharsis/ethermint/rpc/backend"
+	"github.com/tharsis/ethermint/rpc/namespaces/ethereum/debug"
+	"github.com/tharsis/ethermint/rpc/namespaces/ethereum/eth"
+	"github.com/tharsis/ethermint/rpc/namespaces/ethereum/eth/filters"
+	"github.com/tharsis/ethermint/rpc/namespaces/ethereum/miner"
+	"github.com/tharsis/ethermint/rpc/namespaces/ethereum/net"
+	"github.com/tharsis/ethermint/rpc/namespaces/ethereum/personal"
+	"github.com/tharsis/ethermint/rpc/namespaces/ethereum/txpool"
+	"github.com/tharsis/ethermint/rpc/namespaces/ethereum/web3"
+	"github.com/tharsis/ethermint/rpc/types"
 
 	rpcclient "github.com/tendermint/tendermint/rpc/jsonrpc/client"
 )
 
 // RPC namespaces and API version
 const (
+	// Cosmos namespaces
+
+	CosmosNamespace = "cosmos"
+
+	// Ethereum namespaces
+
 	Web3Namespace     = "web3"
 	EthNamespace      = "eth"
 	PersonalNamespace = "personal"
@@ -37,17 +43,17 @@ const (
 	apiVersion = "1.0"
 )
 
-// APICreator creates the json-rpc api implementations.
+// APICreator creates the JSON-RPC API implementations.
 type APICreator = func(*server.Context, client.Context, *rpcclient.WSClient) []rpc.API
 
-// apiCreators defines the json-rpc api namespaces.
+// apiCreators defines the JSON-RPC API namespaces.
 var apiCreators map[string]APICreator
 
 func init() {
 	apiCreators = map[string]APICreator{
 		EthNamespace: func(ctx *server.Context, clientCtx client.Context, tmWSClient *rpcclient.WSClient) []rpc.API {
 			nonceLock := new(types.AddrLocker)
-			evmBackend := backend.NewEVMBackend(ctx, ctx.Logger, clientCtx)
+			evmBackend := backend.NewBackend(ctx, ctx.Logger, clientCtx)
 			return []rpc.API{
 				{
 					Namespace: EthNamespace,
@@ -84,7 +90,7 @@ func init() {
 			}
 		},
 		PersonalNamespace: func(ctx *server.Context, clientCtx client.Context, _ *rpcclient.WSClient) []rpc.API {
-			evmBackend := backend.NewEVMBackend(ctx, ctx.Logger, clientCtx)
+			evmBackend := backend.NewBackend(ctx, ctx.Logger, clientCtx)
 			return []rpc.API{
 				{
 					Namespace: PersonalNamespace,
@@ -105,7 +111,7 @@ func init() {
 			}
 		},
 		DebugNamespace: func(ctx *server.Context, clientCtx client.Context, _ *rpcclient.WSClient) []rpc.API {
-			evmBackend := backend.NewEVMBackend(ctx, ctx.Logger, clientCtx)
+			evmBackend := backend.NewBackend(ctx, ctx.Logger, clientCtx)
 			return []rpc.API{
 				{
 					Namespace: DebugNamespace,
@@ -116,7 +122,7 @@ func init() {
 			}
 		},
 		MinerNamespace: func(ctx *server.Context, clientCtx client.Context, _ *rpcclient.WSClient) []rpc.API {
-			evmBackend := backend.NewEVMBackend(ctx, ctx.Logger, clientCtx)
+			evmBackend := backend.NewBackend(ctx, ctx.Logger, clientCtx)
 			return []rpc.API{
 				{
 					Namespace: MinerNamespace,

rpc/backend/backend.go

@@ -0,0 +1,114 @@
+package backend
+
+import (
+	"context"
+	"math/big"
+	"time"
+
+	"github.com/cosmos/cosmos-sdk/client"
+	"github.com/cosmos/cosmos-sdk/server"
+	sdk "github.com/cosmos/cosmos-sdk/types"
+	"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/params"
+	"github.com/ethereum/go-ethereum/rpc"
+	"github.com/tendermint/tendermint/libs/log"
+	tmrpctypes "github.com/tendermint/tendermint/rpc/core/types"
+	"github.com/tharsis/ethermint/rpc/types"
+	"github.com/tharsis/ethermint/server/config"
+	ethermint "github.com/tharsis/ethermint/types"
+	evmtypes "github.com/tharsis/ethermint/x/evm/types"
+)
+
+// BackendI implements the Cosmos and EVM backend.
+type BackendI interface { // nolint: revive
+	CosmosBackend
+	EVMBackend
+}
+
+// CosmosBackend implements the functionality shared within cosmos namespaces
+// as defined by Wallet Connect V2: https://docs.walletconnect.com/2.0/json-rpc/cosmos.
+// Implemented by Backend.
+type CosmosBackend interface {
+	// TODO: define
+	// GetAccounts()
+	// SignDirect()
+	// SignAmino()
+}
+
+// EVMBackend implements the functionality shared within ethereum namespaces
+// as defined by EIP-1474: https://github.com/ethereum/EIPs/blob/master/EIPS/eip-1474.md
+// Implemented by Backend.
+type EVMBackend interface {
+	// General Ethereum API
+	RPCGasCap() uint64            // global gas cap for eth_call over rpc: DoS protection
+	RPCEVMTimeout() time.Duration // global timeout for eth_call over rpc: DoS protection
+	RPCTxFeeCap() float64         // RPCTxFeeCap is the global transaction fee(price * gaslimit) cap for send-transaction variants. The unit is ether.
+
+	RPCMinGasPrice() int64
+	SuggestGasTipCap(baseFee *big.Int) (*big.Int, error)
+
+	// Blockchain API
+	BlockNumber() (hexutil.Uint64, error)
+	GetTendermintBlockByNumber(blockNum types.BlockNumber) (*tmrpctypes.ResultBlock, error)
+	GetTendermintBlockByHash(blockHash common.Hash) (*tmrpctypes.ResultBlock, error)
+	GetBlockByNumber(blockNum types.BlockNumber, fullTx bool) (map[string]interface{}, error)
+	GetBlockByHash(hash common.Hash, fullTx bool) (map[string]interface{}, error)
+	BlockByNumber(blockNum types.BlockNumber) (*ethtypes.Block, error)
+	BlockByHash(blockHash common.Hash) (*ethtypes.Block, error)
+	CurrentHeader() *ethtypes.Header
+	HeaderByNumber(blockNum types.BlockNumber) (*ethtypes.Header, error)
+	HeaderByHash(blockHash common.Hash) (*ethtypes.Header, error)
+	PendingTransactions() ([]*sdk.Tx, error)
+	GetTransactionCount(address common.Address, blockNum types.BlockNumber) (*hexutil.Uint64, error)
+	SendTransaction(args evmtypes.TransactionArgs) (common.Hash, error)
+	GetCoinbase() (sdk.AccAddress, error)
+	GetTransactionByHash(txHash common.Hash) (*types.RPCTransaction, error)
+	GetTxByEthHash(txHash common.Hash) (*tmrpctypes.ResultTx, error)
+	GetTxByTxIndex(height int64, txIndex uint) (*tmrpctypes.ResultTx, error)
+	EstimateGas(args evmtypes.TransactionArgs, blockNrOptional *types.BlockNumber) (hexutil.Uint64, error)
+	BaseFee(height int64) (*big.Int, error)
+
+	// Fee API
+	FeeHistory(blockCount rpc.DecimalOrHex, lastBlock rpc.BlockNumber, rewardPercentiles []float64) (*types.FeeHistoryResult, error)
+
+	// Filter API
+	BloomStatus() (uint64, uint64)
+	GetLogs(hash common.Hash) ([][]*ethtypes.Log, error)
+	GetLogsByHeight(height *int64) ([][]*ethtypes.Log, error)
+	ChainConfig() *params.ChainConfig
+	SetTxDefaults(args evmtypes.TransactionArgs) (evmtypes.TransactionArgs, error)
+	GetEthereumMsgsFromTendermintBlock(block *tmrpctypes.ResultBlock, blockRes *tmrpctypes.ResultBlockResults) []*evmtypes.MsgEthereumTx
+}
+
+var _ BackendI = (*Backend)(nil)
+
+// Backend implements the BackendI interface
+type Backend struct {
+	ctx         context.Context
+	clientCtx   client.Context
+	queryClient *types.QueryClient // gRPC query client
+	logger      log.Logger
+	chainID     *big.Int
+	cfg         config.Config
+}
+
+// NewBackend creates a new Backend instance for cosmos and ethereum namespaces
+func NewBackend(ctx *server.Context, logger log.Logger, clientCtx client.Context) *Backend {
+	chainID, err := ethermint.ParseChainID(clientCtx.ChainID)
+	if err != nil {
+		panic(err)
+	}
+
+	appConf := config.GetConfig(ctx.Viper)
+
+	return &Backend{
+		ctx:         context.Background(),
+		clientCtx:   clientCtx,
+		queryClient: types.NewQueryClient(clientCtx),
+		logger:      logger.With("module", "backend"),
+		chainID:     chainID,
+		cfg:         appConf,
+	}
+}

rpc/backend/utils.go

@@ -6,27 +6,47 @@ import (
 	"errors"
 	"fmt"
 	"math/big"
+	"sort"
 
 	sdk "github.com/cosmos/cosmos-sdk/types"
 	authtypes "github.com/cosmos/cosmos-sdk/x/auth/types"
+
 	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/common/hexutil"
 	ethtypes "github.com/ethereum/go-ethereum/core/types"
+
 	abci "github.com/tendermint/tendermint/abci/types"
 	"github.com/tendermint/tendermint/libs/log"
+	tmrpctypes "github.com/tendermint/tendermint/rpc/core/types"
 
-	"github.com/ethereum/go-ethereum/common/hexutil"
-	"github.com/tharsis/ethermint/rpc/ethereum/types"
+	"github.com/tharsis/ethermint/rpc/types"
 	evmtypes "github.com/tharsis/ethermint/x/evm/types"
 )
 
+type txGasAndReward struct {
+	gasUsed uint64
+	reward  *big.Int
+}
+
+type sortGasAndReward []txGasAndReward
+
+func (s sortGasAndReward) Len() int { return len(s) }
+func (s sortGasAndReward) Swap(i, j int) {
+	s[i], s[j] = s[j], s[i]
+}
+
+func (s sortGasAndReward) Less(i, j int) bool {
+	return s[i].reward.Cmp(s[j].reward) < 0
+}
+
 // SetTxDefaults populates tx message with default values in case they are not
 // provided on the args
-func (e *EVMBackend) SetTxDefaults(args evmtypes.TransactionArgs) (evmtypes.TransactionArgs, error) {
+func (b *Backend) SetTxDefaults(args evmtypes.TransactionArgs) (evmtypes.TransactionArgs, error) {
 	if args.GasPrice != nil && (args.MaxFeePerGas != nil || args.MaxPriorityFeePerGas != nil) {
 		return args, errors.New("both gasPrice and (maxFeePerGas or maxPriorityFeePerGas) specified")
 	}
 
-	head := e.CurrentHeader()
+	head := b.CurrentHeader()
 	if head == nil {
 		return args, errors.New("latest header is nil")
 	}
@@ -37,7 +57,7 @@ func (e *EVMBackend) SetTxDefaults(args evmtypes.TransactionArgs) (evmtypes.Tran
 		// In this clause, user left some fields unspecified.
 		if head.BaseFee != nil && args.GasPrice == nil {
 			if args.MaxPriorityFeePerGas == nil {
-				tip, err := e.SuggestGasTipCap(head.BaseFee)
+				tip, err := b.SuggestGasTipCap(head.BaseFee)
 				if err != nil {
 					return args, err
 				}
@@ -62,7 +82,7 @@ func (e *EVMBackend) SetTxDefaults(args evmtypes.TransactionArgs) (evmtypes.Tran
 			}
 
 			if args.GasPrice == nil {
-				price, err := e.SuggestGasTipCap(head.BaseFee)
+				price, err := b.SuggestGasTipCap(head.BaseFee)
 				if err != nil {
 					return args, err
 				}
@@ -88,7 +108,7 @@ func (e *EVMBackend) SetTxDefaults(args evmtypes.TransactionArgs) (evmtypes.Tran
 	if args.Nonce == nil {
 		// get the nonce from the account retriever
 		// ignore error in case tge account doesn't exist yet
-		nonce, _ := e.getAccountNonce(*args.From, true, 0, e.logger)
+		nonce, _ := b.getAccountNonce(*args.From, true, 0, b.logger)
 		args.Nonce = (*hexutil.Uint64)(&nonce)
 	}
 
@@ -131,16 +151,16 @@ func (e *EVMBackend) SetTxDefaults(args evmtypes.TransactionArgs) (evmtypes.Tran
 		}
 
 		blockNr := types.NewBlockNumber(big.NewInt(0))
-		estimated, err := e.EstimateGas(callArgs, &blockNr)
+		estimated, err := b.EstimateGas(callArgs, &blockNr)
 		if err != nil {
 			return args, err
 		}
 		args.Gas = &estimated
-		e.logger.Debug("estimate gas usage automatically", "gas", args.Gas)
+		b.logger.Debug("estimate gas usage automatically", "gas", args.Gas)
 	}
 
 	if args.ChainID == nil {
-		args.ChainID = (*hexutil.Big)(e.chainID)
+		args.ChainID = (*hexutil.Big)(b.chainID)
 	}
 
 	return args, nil
@@ -150,14 +170,14 @@ func (e *EVMBackend) SetTxDefaults(args evmtypes.TransactionArgs) (evmtypes.Tran
 // If the pending value is true, it will iterate over the mempool (pending)
 // txs in order to compute and return the pending tx sequence.
 // Todo: include the ability to specify a blockNumber
-func (e *EVMBackend) getAccountNonce(accAddr common.Address, pending bool, height int64, logger log.Logger) (uint64, error) {
-	queryClient := authtypes.NewQueryClient(e.clientCtx)
+func (b *Backend) getAccountNonce(accAddr common.Address, pending bool, height int64, logger log.Logger) (uint64, error) {
+	queryClient := authtypes.NewQueryClient(b.clientCtx)
 	res, err := queryClient.Account(types.ContextWithHeight(height), &authtypes.QueryAccountRequest{Address: sdk.AccAddress(accAddr.Bytes()).String()})
 	if err != nil {
 		return 0, err
 	}
 	var acc authtypes.AccountI
-	if err := e.clientCtx.InterfaceRegistry.UnpackAny(res.Account, &acc); err != nil {
+	if err := b.clientCtx.InterfaceRegistry.UnpackAny(res.Account, &acc); err != nil {
 		return 0, err
 	}
 
@@ -169,7 +189,7 @@ func (e *EVMBackend) getAccountNonce(accAddr common.Address, pending bool, heigh
 
 	// the account retriever doesn't include the uncommitted transactions on the nonce so we need to
 	// to manually add them.
-	pendingTxs, err := e.PendingTransactions()
+	pendingTxs, err := b.PendingTransactions()
 	if err != nil {
 		logger.Error("failed to fetch pending transactions", "error", err.Error())
 		return nonce, nil
@@ -185,7 +205,7 @@ func (e *EVMBackend) getAccountNonce(accAddr common.Address, pending bool, heigh
 				break
 			}
 
-			sender, err := ethMsg.GetSender(e.chainID)
+			sender, err := ethMsg.GetSender(b.chainID)
 			if err != nil {
 				continue
 			}
@@ -198,6 +218,104 @@ func (e *EVMBackend) getAccountNonce(accAddr common.Address, pending bool, heigh
 	return nonce, nil
 }
 
+// output: targetOneFeeHistory
+func (b *Backend) processBlock(
+	tendermintBlock *tmrpctypes.ResultBlock,
+	ethBlock *map[string]interface{},
+	rewardPercentiles []float64,
+	tendermintBlockResult *tmrpctypes.ResultBlockResults,
+	targetOneFeeHistory *types.OneFeeHistory,
+) error {
+	blockHeight := tendermintBlock.Block.Height
+	blockBaseFee, err := b.BaseFee(blockHeight)
+	if err != nil {
+		return err
+	}
+
+	// set basefee
+	targetOneFeeHistory.BaseFee = blockBaseFee
+
+	// set gas used ratio
+	gasLimitUint64, ok := (*ethBlock)["gasLimit"].(hexutil.Uint64)
+	if !ok {
+		return fmt.Errorf("invalid gas limit type: %T", (*ethBlock)["gasLimit"])
+	}
+
+	gasUsedBig, ok := (*ethBlock)["gasUsed"].(*hexutil.Big)
+	if !ok {
+		return fmt.Errorf("invalid gas used type: %T", (*ethBlock)["gasUsed"])
+	}
+
+	gasusedfloat, _ := new(big.Float).SetInt(gasUsedBig.ToInt()).Float64()
+
+	if gasLimitUint64 <= 0 {
+		return fmt.Errorf("gasLimit of block height %d should be bigger than 0 , current gaslimit %d", blockHeight, gasLimitUint64)
+	}
+
+	gasUsedRatio := gasusedfloat / float64(gasLimitUint64)
+	blockGasUsed := gasusedfloat
+	targetOneFeeHistory.GasUsedRatio = gasUsedRatio
+
+	rewardCount := len(rewardPercentiles)
+	targetOneFeeHistory.Reward = make([]*big.Int, rewardCount)
+	for i := 0; i < rewardCount; i++ {
+		targetOneFeeHistory.Reward[i] = big.NewInt(0)
+	}
+
+	// check tendermintTxs
+	tendermintTxs := tendermintBlock.Block.Txs
+	tendermintTxResults := tendermintBlockResult.TxsResults
+	tendermintTxCount := len(tendermintTxs)
+
+	var sorter sortGasAndReward
+
+	for i := 0; i < tendermintTxCount; i++ {
+		eachTendermintTx := tendermintTxs[i]
+		eachTendermintTxResult := tendermintTxResults[i]
+
+		tx, err := b.clientCtx.TxConfig.TxDecoder()(eachTendermintTx)
+		if err != nil {
+			b.logger.Debug("failed to decode transaction in block", "height", blockHeight, "error", err.Error())
+			continue
+		}
+		txGasUsed := uint64(eachTendermintTxResult.GasUsed)
+		for _, msg := range tx.GetMsgs() {
+			ethMsg, ok := msg.(*evmtypes.MsgEthereumTx)
+			if !ok {
+				continue
+			}
+			tx := ethMsg.AsTransaction()
+			reward := tx.EffectiveGasTipValue(blockBaseFee)
+			if reward == nil {
+				reward = big.NewInt(0)
+			}
+			sorter = append(sorter, txGasAndReward{gasUsed: txGasUsed, reward: reward})
+		}
+	}
+
+	// return an all zero row if there are no transactions to gather data from
+	ethTxCount := len(sorter)
+	if ethTxCount == 0 {
+		return nil
+	}
+
+	sort.Sort(sorter)
+
+	var txIndex int
+	sumGasUsed := sorter[0].gasUsed
+
+	for i, p := range rewardPercentiles {
+		thresholdGasUsed := uint64(blockGasUsed * p / 100)
+		for sumGasUsed < thresholdGasUsed && txIndex < ethTxCount-1 {
+			txIndex++
+			sumGasUsed += sorter[txIndex].gasUsed
+		}
+		targetOneFeeHistory.Reward[i] = sorter[txIndex].reward
+	}
+
+	return nil
+}
+
 // AllTxLogsFromEvents parses all ethereum logs from cosmos events
 func AllTxLogsFromEvents(events []abci.Event) ([][]*ethtypes.Log, error) {
 	allLogs := make([][]*ethtypes.Log, 0, 4)

rpc/ethereum/backend/feebackend.go

@@ -1,223 +0,0 @@
-package backend
-
-import (
-	"fmt"
-	"math/big"
-	"sort"
-
-	"github.com/ethereum/go-ethereum/common/hexutil"
-	"github.com/ethereum/go-ethereum/rpc"
-	tmrpctypes "github.com/tendermint/tendermint/rpc/core/types"
-	rpctypes "github.com/tharsis/ethermint/rpc/ethereum/types"
-	evmtypes "github.com/tharsis/ethermint/x/evm/types"
-)
-
-type (
-	txGasAndReward struct {
-		gasUsed uint64
-		reward  *big.Int
-	}
-	sortGasAndReward []txGasAndReward
-)
-
-func (s sortGasAndReward) Len() int { return len(s) }
-func (s sortGasAndReward) Swap(i, j int) {
-	s[i], s[j] = s[j], s[i]
-}
-
-func (s sortGasAndReward) Less(i, j int) bool {
-	return s[i].reward.Cmp(s[j].reward) < 0
-}
-
-// output: targetOneFeeHistory
-func (e *EVMBackend) processBlock(
-	tendermintBlock *tmrpctypes.ResultBlock,
-	ethBlock *map[string]interface{},
-	rewardPercentiles []float64,
-	tendermintBlockResult *tmrpctypes.ResultBlockResults,
-	targetOneFeeHistory *rpctypes.OneFeeHistory,
-) error {
-	blockHeight := tendermintBlock.Block.Height
-	blockBaseFee, err := e.BaseFee(blockHeight)
-	if err != nil {
-		return err
-	}
-
-	// set basefee
-	targetOneFeeHistory.BaseFee = blockBaseFee
-
-	// set gas used ratio
-	gasLimitUint64, ok := (*ethBlock)["gasLimit"].(hexutil.Uint64)
-	if !ok {
-		return fmt.Errorf("invalid gas limit type: %T", (*ethBlock)["gasLimit"])
-	}
-
-	gasUsedBig, ok := (*ethBlock)["gasUsed"].(*hexutil.Big)
-	if !ok {
-		return fmt.Errorf("invalid gas used type: %T", (*ethBlock)["gasUsed"])
-	}
-
-	gasusedfloat, _ := new(big.Float).SetInt(gasUsedBig.ToInt()).Float64()
-
-	if gasLimitUint64 <= 0 {
-		return fmt.Errorf("gasLimit of block height %d should be bigger than 0 , current gaslimit %d", blockHeight, gasLimitUint64)
-	}
-
-	gasUsedRatio := gasusedfloat / float64(gasLimitUint64)
-	blockGasUsed := gasusedfloat
-	targetOneFeeHistory.GasUsedRatio = gasUsedRatio
-
-	rewardCount := len(rewardPercentiles)
-	targetOneFeeHistory.Reward = make([]*big.Int, rewardCount)
-	for i := 0; i < rewardCount; i++ {
-		targetOneFeeHistory.Reward[i] = big.NewInt(0)
-	}
-
-	// check tendermintTxs
-	tendermintTxs := tendermintBlock.Block.Txs
-	tendermintTxResults := tendermintBlockResult.TxsResults
-	tendermintTxCount := len(tendermintTxs)
-
-	var sorter sortGasAndReward
-
-	for i := 0; i < tendermintTxCount; i++ {
-		eachTendermintTx := tendermintTxs[i]
-		eachTendermintTxResult := tendermintTxResults[i]
-
-		tx, err := e.clientCtx.TxConfig.TxDecoder()(eachTendermintTx)
-		if err != nil {
-			e.logger.Debug("failed to decode transaction in block", "height", blockHeight, "error", err.Error())
-			continue
-		}
-		txGasUsed := uint64(eachTendermintTxResult.GasUsed)
-		for _, msg := range tx.GetMsgs() {
-			ethMsg, ok := msg.(*evmtypes.MsgEthereumTx)
-			if !ok {
-				continue
-			}
-			tx := ethMsg.AsTransaction()
-			reward := tx.EffectiveGasTipValue(blockBaseFee)
-			if reward == nil {
-				reward = big.NewInt(0)
-			}
-			sorter = append(sorter, txGasAndReward{gasUsed: txGasUsed, reward: reward})
-		}
-	}
-
-	// return an all zero row if there are no transactions to gather data from
-	ethTxCount := len(sorter)
-	if ethTxCount == 0 {
-		return nil
-	}
-
-	sort.Sort(sorter)
-
-	var txIndex int
-	sumGasUsed := sorter[0].gasUsed
-
-	for i, p := range rewardPercentiles {
-		thresholdGasUsed := uint64(blockGasUsed * p / 100)
-		for sumGasUsed < thresholdGasUsed && txIndex < ethTxCount-1 {
-			txIndex++
-			sumGasUsed += sorter[txIndex].gasUsed
-		}
-		targetOneFeeHistory.Reward[i] = sorter[txIndex].reward
-	}
-
-	return nil
-}
-
-// FeeHistory returns data relevant for fee estimation based on the specified range of blocks.
-func (e *EVMBackend) FeeHistory(
-	userBlockCount rpc.DecimalOrHex, // number blocks to fetch, maximum is 100
-	lastBlock rpc.BlockNumber, // the block to start search , to oldest
-	rewardPercentiles []float64, // percentiles to fetch reward
-) (*rpctypes.FeeHistoryResult, error) {
-	blockEnd := int64(lastBlock)
-
-	if blockEnd <= 0 {
-		blockNumber, err := e.BlockNumber()
-		if err != nil {
-			return nil, err
-		}
-		blockEnd = int64(blockNumber)
-	}
-	userBlockCountInt := int64(userBlockCount)
-	maxBlockCount := int64(e.cfg.JSONRPC.FeeHistoryCap)
-	if userBlockCountInt > maxBlockCount {
-		return nil, fmt.Errorf("FeeHistory user block count %d higher than %d", userBlockCountInt, maxBlockCount)
-	}
-	blockStart := blockEnd - userBlockCountInt
-	if blockStart < 0 {
-		blockStart = 0
-	}
-
-	blockCount := blockEnd - blockStart
-
-	oldestBlock := (*hexutil.Big)(big.NewInt(blockStart))
-
-	// prepare space
-	reward := make([][]*hexutil.Big, blockCount)
-	rewardCount := len(rewardPercentiles)
-	for i := 0; i < int(blockCount); i++ {
-		reward[i] = make([]*hexutil.Big, rewardCount)
-	}
-	thisBaseFee := make([]*hexutil.Big, blockCount)
-	thisGasUsedRatio := make([]float64, blockCount)
-
-	// rewards should only be calculated if reward percentiles were included
-	calculateRewards := rewardCount != 0
-
-	// fetch block
-	for blockID := blockStart; blockID < blockEnd; blockID++ {
-		index := int32(blockID - blockStart)
-		// eth block
-		ethBlock, err := e.GetBlockByNumber(rpctypes.BlockNumber(blockID), true)
-		if ethBlock == nil {
-			return nil, err
-		}
-
-		// tendermint block
-		tendermintblock, err := e.GetTendermintBlockByNumber(rpctypes.BlockNumber(blockID))
-		if tendermintblock == nil {
-			return nil, err
-		}
-
-		// tendermint block result
-		tendermintBlockResult, err := e.clientCtx.Client.BlockResults(e.ctx, &tendermintblock.Block.Height)
-		if tendermintBlockResult == nil {
-			e.logger.Debug("block result not found", "height", tendermintblock.Block.Height, "error", err.Error())
-			return nil, err
-		}
-
-		oneFeeHistory := rpctypes.OneFeeHistory{}
-		err = e.processBlock(tendermintblock, &ethBlock, rewardPercentiles, tendermintBlockResult, &oneFeeHistory)
-		if err != nil {
-			return nil, err
-		}
-
-		// copy
-		thisBaseFee[index] = (*hexutil.Big)(oneFeeHistory.BaseFee)
-		thisGasUsedRatio[index] = oneFeeHistory.GasUsedRatio
-		if calculateRewards {
-			for j := 0; j < rewardCount; j++ {
-				reward[index][j] = (*hexutil.Big)(oneFeeHistory.Reward[j])
-				if reward[index][j] == nil {
-					reward[index][j] = (*hexutil.Big)(big.NewInt(0))
-				}
-			}
-		}
-	}
-
-	feeHistory := rpctypes.FeeHistoryResult{
-		OldestBlock:  oldestBlock,
-		BaseFee:      thisBaseFee,
-		GasUsedRatio: thisGasUsedRatio,
-	}
-
-	if calculateRewards {
-		feeHistory.Reward = reward
-	}
-
-	return &feeHistory, nil
-}

rpc/namespaces/ethereum/debug/api.go

@@ -28,8 +28,8 @@ import (
 	"github.com/ethereum/go-ethereum/consensus/ethash"
 	"github.com/ethereum/go-ethereum/rlp"
 	"github.com/tendermint/tendermint/libs/log"
-	"github.com/tharsis/ethermint/rpc/ethereum/backend"
-	rpctypes "github.com/tharsis/ethermint/rpc/ethereum/types"
+	"github.com/tharsis/ethermint/rpc/backend"
+	rpctypes "github.com/tharsis/ethermint/rpc/types"
 )
 
 // HandlerT keeps track of the cpu profiler and trace execution
@@ -45,7 +45,7 @@ type HandlerT struct {
 type API struct {
 	ctx         *server.Context
 	logger      log.Logger
-	backend     backend.Backend
+	backend     backend.EVMBackend
 	clientCtx   client.Context
 	queryClient *rpctypes.QueryClient
 	handler     *HandlerT
@@ -54,7 +54,7 @@ type API struct {
 // NewAPI creates a new API definition for the tracing methods of the Ethereum service.
 func NewAPI(
 	ctx *server.Context,
-	backend backend.Backend,
+	backend backend.EVMBackend,
 	clientCtx client.Context,
 ) *API {
 	return &API{

rpc/namespaces/ethereum/eth/api.go

@@ -36,8 +36,8 @@ import (
 	"github.com/ethereum/go-ethereum/crypto"
 
 	"github.com/tharsis/ethermint/crypto/hd"
-	"github.com/tharsis/ethermint/rpc/ethereum/backend"
-	rpctypes "github.com/tharsis/ethermint/rpc/ethereum/types"
+	"github.com/tharsis/ethermint/rpc/backend"
+	rpctypes "github.com/tharsis/ethermint/rpc/types"
 	ethermint "github.com/tharsis/ethermint/types"
 	evmtypes "github.com/tharsis/ethermint/x/evm/types"
 )
@@ -49,7 +49,7 @@ type PublicAPI struct {
 	queryClient  *rpctypes.QueryClient
 	chainIDEpoch *big.Int
 	logger       log.Logger
-	backend      backend.Backend
+	backend      backend.EVMBackend
 	nonceLock    *rpctypes.AddrLocker
 	signer       ethtypes.Signer
 }
@@ -58,7 +58,7 @@ type PublicAPI struct {
 func NewPublicAPI(
 	logger log.Logger,
 	clientCtx client.Context,
-	backend backend.Backend,
+	backend backend.EVMBackend,
 	nonceLock *rpctypes.AddrLocker,
 ) *PublicAPI {
 	eip155ChainID, err := ethermint.ParseChainID(clientCtx.ChainID)

rpc/namespaces/ethereum/eth/filters/api.go

@@ -7,7 +7,7 @@ import (
 	"time"
 
 	"github.com/cosmos/cosmos-sdk/client"
-	"github.com/tharsis/ethermint/rpc/ethereum/types"
+	"github.com/tharsis/ethermint/rpc/types"
 
 	"github.com/tendermint/tendermint/libs/log"
 

rpc/namespaces/ethereum/eth/filters/filters.go

@@ -5,7 +5,7 @@ import (
 	"encoding/binary"
 	"math/big"
 
-	"github.com/tharsis/ethermint/rpc/ethereum/types"
+	"github.com/tharsis/ethermint/rpc/types"
 
 	"github.com/pkg/errors"
 	"github.com/tendermint/tendermint/libs/log"

rpc/namespaces/ethereum/eth/filters/subscription.go

@@ -31,7 +31,7 @@ func (s Subscription) ID() rpc.ID {
 }
 
 // Unsubscribe from the current subscription to Tendermint Websocket. It sends an error to the
-// subscription error channel if unsubscription fails.
+// subscription error channel if unsubscribe fails.
 func (s *Subscription) Unsubscribe(es *EventSystem) {
 	go func() {
 	uninstallLoop:

rpc/namespaces/ethereum/miner/api.go

@@ -21,8 +21,8 @@ import (
 	"github.com/tendermint/tendermint/libs/log"
 	tmtypes "github.com/tendermint/tendermint/types"
 
-	"github.com/tharsis/ethermint/rpc/ethereum/backend"
-	rpctypes "github.com/tharsis/ethermint/rpc/ethereum/types"
+	"github.com/tharsis/ethermint/rpc/backend"
+	rpctypes "github.com/tharsis/ethermint/rpc/types"
 	"github.com/tharsis/ethermint/server/config"
 )
 
@@ -31,14 +31,14 @@ type API struct {
 	ctx       *server.Context
 	logger    log.Logger
 	clientCtx client.Context
-	backend   backend.Backend
+	backend   backend.EVMBackend
 }
 
 // NewPrivateAPI creates an instance of the Miner API.
 func NewPrivateAPI(
 	ctx *server.Context,
 	clientCtx client.Context,
-	backend backend.Backend,
+	backend backend.EVMBackend,
 ) *API {
 	return &API{
 		ctx:       ctx,

rpc/namespaces/ethereum/personal/api.go

@@ -6,7 +6,7 @@ import (
 	"os"
 	"time"
 
-	"github.com/tharsis/ethermint/rpc/ethereum/backend"
+	"github.com/tharsis/ethermint/rpc/backend"
 
 	"github.com/cosmos/cosmos-sdk/client"
 
@@ -31,13 +31,17 @@ import (
 // PrivateAccountAPI is the personal_ prefixed set of APIs in the Web3 JSON-RPC spec.
 type PrivateAccountAPI struct {
 	clientCtx  client.Context
-	backend    backend.Backend
+	backend    backend.EVMBackend
 	logger     log.Logger
 	hdPathIter ethermint.HDPathIterator
 }
 
 // NewAPI creates an instance of the public Personal Eth API.
-func NewAPI(logger log.Logger, clientCtx client.Context, backend backend.Backend) *PrivateAccountAPI {
+func NewAPI(
+	logger log.Logger,
+	clientCtx client.Context,
+	backend backend.EVMBackend,
+) *PrivateAccountAPI {
 	cfg := sdk.GetConfig()
 	basePath := cfg.GetFullBIP44Path()
 

rpc/namespaces/ethereum/txpool/api.go

@@ -5,7 +5,7 @@ import (
 
 	"github.com/ethereum/go-ethereum/common/hexutil"
 
-	"github.com/tharsis/ethermint/rpc/ethereum/types"
+	"github.com/tharsis/ethermint/rpc/types"
 )
 
 // PublicAPI offers and API for the transaction pool. It only operates on data that is non-confidential.

rpc/websockets.go

@@ -26,9 +26,9 @@ import (
 	rpcclient "github.com/tendermint/tendermint/rpc/jsonrpc/client"
 	tmtypes "github.com/tendermint/tendermint/types"
 
-	rpcfilters "github.com/tharsis/ethermint/rpc/ethereum/namespaces/eth/filters"
 	"github.com/tharsis/ethermint/rpc/ethereum/pubsub"
-	"github.com/tharsis/ethermint/rpc/ethereum/types"
+	rpcfilters "github.com/tharsis/ethermint/rpc/namespaces/ethereum/eth/filters"
+	"github.com/tharsis/ethermint/rpc/types"
 	"github.com/tharsis/ethermint/server/config"
 	evmtypes "github.com/tharsis/ethermint/x/evm/types"
 )

server/start.go

@@ -41,7 +41,7 @@ import (
 	storetypes "github.com/cosmos/cosmos-sdk/store/types"
 	sdk "github.com/cosmos/cosmos-sdk/types"
 
-	ethdebug "github.com/tharsis/ethermint/rpc/ethereum/namespaces/debug"
+	ethdebug "github.com/tharsis/ethermint/rpc/namespaces/ethereum/debug"
 	"github.com/tharsis/ethermint/server/config"
 	srvflags "github.com/tharsis/ethermint/server/flags"
 )

tests/e2e/integration_test.go

@@ -4,12 +4,13 @@ import (
 	"bytes"
 	"context"
 	"fmt"
+	"math/big"
+	"testing"
+
 	"github.com/cosmos/cosmos-sdk/client/flags"
 	codectypes "github.com/cosmos/cosmos-sdk/codec/types"
 	authtx "github.com/cosmos/cosmos-sdk/x/auth/tx"
-	"github.com/tharsis/ethermint/rpc/ethereum/types"
-	"math/big"
-	"testing"
+	"github.com/tharsis/ethermint/rpc/types"
 
 	sdk "github.com/cosmos/cosmos-sdk/types"
 	evmtypes "github.com/tharsis/ethermint/x/evm/types"
@@ -147,7 +148,7 @@ func (s *IntegrationTestSuite) TestBlock() {
 	s.Require().NoError(err)
 	s.Require().NotNil(blockByHash)
 
-	//Compare blockByNumber and blockByHash results
+	// Compare blockByNumber and blockByHash results
 	s.Require().Equal(blockByNum.Hash(), blockByHash.Hash())
 	s.Require().Equal(blockByNum.Transactions().Len(), blockByHash.Transactions().Len())
 	s.Require().Equal(blockByNum.ParentHash(), blockByHash.ParentHash())
@@ -382,7 +383,7 @@ func (s *IntegrationTestSuite) TestGetBalance() {
 }
 
 func (s *IntegrationTestSuite) TestGetLogs() {
-	//TODO create tests to cover different filterQuery params
+	// TODO create tests to cover different filterQuery params
 	_, contractAddr := s.deployERC20Contract()
 
 	blockNum, err := s.network.Validators[0].JSONRPCClient.BlockNumber(s.ctx)
@@ -408,7 +409,7 @@ func (s *IntegrationTestSuite) TestGetLogs() {
 }
 
 func (s *IntegrationTestSuite) TestTransactionReceiptERC20Transfer() {
-	//start with clean block
+	// start with clean block
 	err := s.network.WaitForNextBlock()
 	s.Require().NoError(err)
 	// deploy erc20 contract
@@ -641,7 +642,6 @@ func (s *IntegrationTestSuite) transferERC20Transaction(contractAddr, to common.
 	receipt := s.expectSuccessReceipt(ercTransferTx.AsTransaction().Hash())
 	s.Require().NotEmpty(receipt.Logs)
 	return ercTransferTx.AsTransaction().Hash()
-
 }
 
 func (s *IntegrationTestSuite) storeValueStorageContract(contractAddr common.Address, amount *big.Int) common.Hash {

tests/rpc/rpc_pending_test.go

@@ -15,7 +15,7 @@ import (
 	"github.com/ethereum/go-ethereum/common/hexutil"
 	"github.com/stretchr/testify/require"
 
-	rpctypes "github.com/tharsis/ethermint/rpc/ethereum/types"
+	rpctypes "github.com/tharsis/ethermint/rpc/types"
 )
 
 // func TestMain(m *testing.M) {

tests/rpc/rpc_test.go

@@ -17,7 +17,7 @@ import (
 
 	"github.com/stretchr/testify/require"
 
-	rpctypes "github.com/tharsis/ethermint/rpc/ethereum/types"
+	rpctypes "github.com/tharsis/ethermint/rpc/types"
 	ethermint "github.com/tharsis/ethermint/types"
 	evmtypes "github.com/tharsis/ethermint/x/evm/types"
 

x/evm/client/cli/query.go

@@ -2,7 +2,7 @@ package cli
 
 import (
 	"github.com/spf13/cobra"
-	rpctypes "github.com/tharsis/ethermint/rpc/ethereum/types"
+	rpctypes "github.com/tharsis/ethermint/rpc/types"
 
 	"github.com/cosmos/cosmos-sdk/client"
 	"github.com/cosmos/cosmos-sdk/client/flags"

x/evm/client/cli/tx.go

@@ -12,7 +12,7 @@ import (
 	"github.com/pkg/errors"
 	"github.com/spf13/cobra"
 
-	rpctypes "github.com/tharsis/ethermint/rpc/ethereum/types"
+	rpctypes "github.com/tharsis/ethermint/rpc/types"
 	"github.com/tharsis/ethermint/x/evm/types"
 )
 

x/evm/client/rest/rest.go

@@ -16,7 +16,7 @@ import (
 	"github.com/cosmos/cosmos-sdk/types/rest"
 	authrest "github.com/cosmos/cosmos-sdk/x/auth/client/rest"
 
-	rpctypes "github.com/tharsis/ethermint/rpc/ethereum/types"
+	rpctypes "github.com/tharsis/ethermint/rpc/types"
 	feemarkettypes "github.com/tharsis/ethermint/x/feemarket/types"
 
 	"github.com/ethereum/go-ethereum/common"