eth/gasprice: implement feeHistory API (#23033)

* eth/gasprice: implement feeHistory API

* eth/gasprice: factored out resolveBlockRange

* eth/gasprice: add sanity check for missing block

* eth/gasprice: fetch actual gas used from receipts

* miner, eth/gasprice: add PendingBlockAndReceipts

* internal/ethapi: use hexutil.Big

* eth/gasprice: return error when requesting beyond head block

* eth/gasprice: fixed tests and return errors correctly

* eth/gasprice: rename receiver name

* eth/gasprice: return directly if blockCount == 0

Co-authored-by: rjl493456442 <garyrong0905@gmail.com>

internal/ethapi/api.go

@@ -80,6 +80,40 @@ func (s *PublicEthereumAPI) MaxPriorityFeePerGas(ctx context.Context) (*hexutil.
 	return (*hexutil.Big)(tipcap), err
 }
 
+type feeHistoryResults struct {
+	FirstBlock   rpc.BlockNumber
+	Reward       [][]*hexutil.Big
+	BaseFee      []*hexutil.Big
+	GasUsedRatio []float64
+}
+
+func (s *PublicEthereumAPI) FeeHistory(ctx context.Context, blockCount int, lastBlock rpc.BlockNumber, rewardPercentiles []float64) (feeHistoryResults, error) {
+	firstBlock, reward, baseFee, gasUsedRatio, err := s.b.FeeHistory(ctx, blockCount, lastBlock, rewardPercentiles)
+	if err != nil {
+		return feeHistoryResults{}, err
+	}
+	results := feeHistoryResults{
+		FirstBlock:   firstBlock,
+		GasUsedRatio: gasUsedRatio,
+	}
+	if reward != nil {
+		results.Reward = make([][]*hexutil.Big, len(reward))
+		for j, w := range reward {
+			results.Reward[j] = make([]*hexutil.Big, len(w))
+			for i, v := range w {
+				results.Reward[j][i] = (*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
 // yet received the latest block headers from its pears. In case it is synchronizing:
 // - startingBlock: block number this node started to synchronise from

internal/ethapi/backend.go

@@ -42,6 +42,7 @@ type Backend interface {
 	// General Ethereum API
 	Downloader() *downloader.Downloader
 	SuggestGasTipCap(ctx context.Context) (*big.Int, error)
+	FeeHistory(ctx context.Context, blockCount int, lastBlock rpc.BlockNumber, rewardPercentiles []float64) (rpc.BlockNumber, [][]*big.Int, []*big.Int, []float64, error)
 	ChainDb() ethdb.Database
 	AccountManager() *accounts.Manager
 	ExtRPCEnabled() bool