Merge pull request #911 from gzliudan/improve_fee_history

eth/gasprice: improve function FeeHistory

Author: gzliudan

eth/gasprice/feehistory.go

@@ -42,6 +42,8 @@ const (
 	// maxBlockFetchers is the max number of goroutines to spin up to pull blocks
 	// for the fee history calculation (mostly relevant for LES).
 	maxBlockFetchers = 4
+	// maxQueryLimit is the max number of requested percentiles.
+	maxQueryLimit = 100
 )
 
 // blockFees represents a single block for processing
@@ -221,6 +223,9 @@ func (oracle *Oracle) FeeHistory(ctx context.Context, blocks uint64, unresolvedL
 	if len(rewardPercentiles) != 0 {
 		maxFeeHistory = oracle.maxBlockHistory
 	}
+	if len(rewardPercentiles) > maxQueryLimit {
+		return common.Big0, nil, nil, nil, fmt.Errorf("%w: over the query limit %d", errInvalidPercentile, maxQueryLimit)
+	}
 	if blocks > maxFeeHistory {
 		log.Warn("Sanitizing fee history length", "requested", blocks, "truncated", maxFeeHistory)
 		blocks = maxFeeHistory

eth/gasprice/feehistory_test.go

@@ -83,6 +83,11 @@ func TestFeeHistory(t *testing.T) {
 		if len(ratio) != c.expCount {
 			t.Fatalf("Test case %d: gasUsedRatio array length mismatch, want %d, got %d", i, c.expCount, len(ratio))
 		}
+		for _, ratio := range ratio {
+			if ratio > 1 {
+				t.Fatalf("Test case %d: gasUsedRatio greater than 1, got %f", i, ratio)
+			}
+		}
 		if err != c.expErr && !errors.Is(err, c.expErr) {
 			t.Fatalf("Test case %d: error mismatch, want %v, got %v", i, c.expErr, err)
 		}