Implemented FeeHistory API

api/api_ethereum.go

@@ -21,6 +21,8 @@ import (
 	"encoding/binary"
 	"errors"
 	"math/big"
+	"strconv"
+	"strings"
 	"sync/atomic"
 	"time"
 
@@ -305,7 +307,7 @@ func (api *EthereumAPI) MaxPriorityFeePerGas(ctx context.Context) (*hexutil.Big,
 	return api.publicKlayAPI.GasPrice(ctx)
 }
 
-type feeHistoryResult struct {
+type FeeHistoryResult struct {
 	OldestBlock  *hexutil.Big     `json:"oldestBlock"`
 	Reward       [][]*hexutil.Big `json:"reward,omitempty"`
 	BaseFee      []*hexutil.Big   `json:"baseFeePerGas,omitempty"`
@@ -315,9 +317,49 @@ type feeHistoryResult struct {
 // DecimalOrHex unmarshals a non-negative decimal or hex parameter into a uint64.
 type DecimalOrHex uint64
 
-func (api *EthereumAPI) FeeHistory(ctx context.Context, blockCount DecimalOrHex, lastBlock rpc.BlockNumber, rewardPercentiles []float64) (*feeHistoryResult, error) {
-	// TODO-Klaytn: Not implemented yet.
-	return nil, nil
+// UnmarshalJSON implements json.Unmarshaler.
+func (dh *DecimalOrHex) UnmarshalJSON(data []byte) error {
+	input := strings.TrimSpace(string(data))
+	if len(input) >= 2 && input[0] == '"' && input[len(input)-1] == '"' {
+		input = input[1 : len(input)-1]
+	}
+
+	value, err := strconv.ParseUint(input, 10, 64)
+	if err != nil {
+		value, err = hexutil.DecodeUint64(input)
+	}
+	if err != nil {
+		return err
+	}
+	*dh = DecimalOrHex(value)
+	return nil
+}
+
+func (api *EthereumAPI) FeeHistory(ctx context.Context, blockCount DecimalOrHex, lastBlock rpc.BlockNumber, rewardPercentiles []float64) (*FeeHistoryResult, error) {
+	oldest, reward, baseFee, gasUsed, err := api.publicKlayAPI.b.FeeHistory(ctx, int(blockCount), lastBlock, rewardPercentiles)
+	if err != nil {
+		return nil, err
+	}
+	results := &FeeHistoryResult{
+		OldestBlock:  (*hexutil.Big)(oldest),
+		GasUsedRatio: gasUsed,
+	}
+	if reward != nil {
+		results.Reward = make([][]*hexutil.Big, len(reward))
+		for i, w := range reward {
+			results.Reward[i] = make([]*hexutil.Big, len(w))
+			for j, v := range w {
+				results.Reward[i][j] = (*hexutil.Big)(v)
+			}
+		}
+	}
+	if baseFee != nil {
+		results.BaseFee = make([]*hexutil.Big, len(baseFee))
+		for i, v := range baseFee {
+			results.BaseFee[i] = (*hexutil.Big)(v)
+		}
+	}
+	return results, nil
 }
 
 // Syncing returns false in case the node is currently not syncing with the network. It can be up to date or has not

api/backend.go

@@ -51,6 +51,7 @@ type Backend interface {
 	AccountManager() accounts.AccountManager
 	RPCGasCap() *big.Int // global gas cap for klay_call over rpc: DoS protection
 	Engine() consensus.Engine
+	FeeHistory(ctx context.Context, blockCount int, lastBlock rpc.BlockNumber, rewardPercentiles []float64) (*big.Int, [][]*big.Int, []*big.Int, []float64, error)
 
 	// BlockChain API
 	SetHead(number uint64)

log/log_modules.go

@@ -124,6 +124,7 @@ const (
 	ChainDataFetcher
 	KAS
 	FORK
+	NodeCnGasPrice
 
 	// ModuleNameLen should be placed at the end of the list.
 	ModuleNameLen
@@ -199,4 +200,5 @@ var moduleNames = [ModuleNameLen]string{
 	"datasync/chaindatafetcher",
 	"kas",
 	"fork",
+	"node/cn/gasprice",
 }

node/cn/api_backend.go

@@ -320,3 +320,7 @@ func (b *CNAPIBackend) RPCGasCap() *big.Int {
 func (b *CNAPIBackend) Engine() consensus.Engine {
 	return b.cn.engine
 }
+
+func (b *CNAPIBackend) FeeHistory(ctx context.Context, blockCount int, lastBlock rpc.BlockNumber, rewardPercentiles []float64) (*big.Int, [][]*big.Int, []*big.Int, []float64, error) {
+	return b.gpo.FeeHistory(ctx, blockCount, lastBlock, rewardPercentiles)
+}

node/cn/config.go

@@ -57,8 +57,10 @@ func GetDefaultConfig() *Config {
 
 		TxPool: blockchain.DefaultTxPoolConfig,
 		GPO: gasprice.Config{
-			Blocks:     20,
-			Percentile: 60,
+			Blocks:           20,
+			Percentile:       60,
+			MaxHeaderHistory: 1024,
+			MaxBlockHistory:  1024,
 		},
 		WsEndpoint: "localhost:8546",