fix(gas-oracle): fetch base fee from the latest L1 block (#920)

Co-authored-by: Péter Garamvölgyi <peter@scroll.io>
Co-authored-by: colinlyguo <colinlyguo@users.noreply.github.com>

common/version/version.go

@@ -5,7 +5,7 @@ import (
 	"runtime/debug"
 )
 
-var tag = "v4.2.20"
+var tag = "v4.2.21"
 
 var commit = func() string {
 	if info, ok := debug.ReadBuildInfo(); ok {

rollup/cmd/gas_oracle/app/app.go

@@ -10,6 +10,7 @@ import (
 	"github.com/prometheus/client_golang/prometheus"
 	"github.com/scroll-tech/go-ethereum/ethclient"
 	"github.com/scroll-tech/go-ethereum/log"
+	"github.com/scroll-tech/go-ethereum/rpc"
 	"github.com/urfave/cli/v2"
 
 	"scroll-tech/common/database"
@@ -92,14 +93,16 @@ func action(ctx *cli.Context) error {
 	}
 	// Start l1 watcher process
 	go utils.LoopWithContext(subCtx, 10*time.Second, func(ctx context.Context) {
-		number, loopErr := butils.GetLatestConfirmedBlockNumber(ctx, l1client, cfg.L1Config.Confirmations)
+		// Fetch the latest block number to decrease the delay when fetching gas prices
+		// Use latest block number - 1 to prevent frequent reorg
+		number, loopErr := butils.GetLatestConfirmedBlockNumber(ctx, l1client, rpc.LatestBlockNumber)
 		if loopErr != nil {
 			log.Error("failed to get block number", "err", loopErr)
 			return
 		}
 
-		if loopErr = l1watcher.FetchBlockHeader(number); loopErr != nil {
-			log.Error("Failed to fetch L1 block header", "lastest", number, "err", loopErr)
+		if loopErr = l1watcher.FetchBlockHeader(number - 1); loopErr != nil {
+			log.Error("Failed to fetch L1 block header", "lastest", number-1, "err", loopErr)
 		}
 	})
 

rollup/internal/orm/l1_block.go

@@ -70,19 +70,30 @@ func (o *L1Block) GetL1Blocks(ctx context.Context, fields map[string]interface{}
 	return l1Blocks, nil
 }
 
-// InsertL1Blocks batch insert l1 blocks
+// InsertL1Blocks batch inserts l1 blocks.
+// If there's a block number conflict (e.g., due to reorg), soft deletes the existing block and inserts the new one.
 func (o *L1Block) InsertL1Blocks(ctx context.Context, blocks []L1Block) error {
 	if len(blocks) == 0 {
 		return nil
 	}
 
-	db := o.db.WithContext(ctx)
-	db = db.Model(&L1Block{})
-
-	if err := db.Create(&blocks).Error; err != nil {
-		return fmt.Errorf("L1Block.InsertL1Blocks error: %w", err)
-	}
-	return nil
+	return o.db.Transaction(func(tx *gorm.DB) error {
+		var blockNumbers []uint64
+		for _, block := range blocks {
+			blockNumbers = append(blockNumbers, block.Number)
+		}
+
+		db := tx.WithContext(ctx)
+		db = db.Model(&L1Block{})
+		if err := db.Where("number IN (?)", blockNumbers).Delete(&L1Block{}).Error; err != nil {
+			return fmt.Errorf("L1Block.InsertL1Blocks error: soft deleting blocks failed, block numbers: %v, error: %w", blockNumbers, err)
+		}
+
+		if err := db.Create(&blocks).Error; err != nil {
+			return fmt.Errorf("L1Block.InsertL1Blocks error: %w", err)
+		}
+		return nil
+	})
 }
 
 // UpdateL1GasOracleStatusAndOracleTxHash update l1 gas oracle status and oracle tx hash

rollup/internal/orm/orm_test.go

@@ -89,6 +89,51 @@ func tearDownEnv(t *testing.T) {
 	base.Free()
 }
 
+func TestL1BlockOrm(t *testing.T) {
+	sqlDB, err := db.DB()
+	assert.NoError(t, err)
+	assert.NoError(t, migrate.ResetDB(sqlDB))
+
+	l1BlockOrm := NewL1Block(db)
+
+	// mock blocks
+	block1 := L1Block{Number: 1, Hash: "hash1"}
+	block2 := L1Block{Number: 2, Hash: "hash2"}
+	block2AfterReorg := L1Block{Number: 2, Hash: "hash3"}
+
+	err = l1BlockOrm.InsertL1Blocks(context.Background(), []L1Block{block1, block2})
+	assert.NoError(t, err)
+
+	height, err := l1BlockOrm.GetLatestL1BlockHeight(context.Background())
+	assert.NoError(t, err)
+	assert.Equal(t, uint64(2), height)
+
+	blocks, err := l1BlockOrm.GetL1Blocks(context.Background(), map[string]interface{}{})
+	assert.NoError(t, err)
+	assert.Len(t, blocks, 2)
+	assert.Equal(t, "hash1", blocks[0].Hash)
+	assert.Equal(t, "hash2", blocks[1].Hash)
+
+	// reorg handling: insert another block with same height and different hash
+	err = l1BlockOrm.InsertL1Blocks(context.Background(), []L1Block{block2AfterReorg})
+	assert.NoError(t, err)
+
+	blocks, err = l1BlockOrm.GetL1Blocks(context.Background(), map[string]interface{}{})
+	assert.NoError(t, err)
+	assert.Len(t, blocks, 2)
+	assert.Equal(t, "hash1", blocks[0].Hash)
+	assert.Equal(t, "hash3", blocks[1].Hash)
+
+	err = l1BlockOrm.UpdateL1GasOracleStatusAndOracleTxHash(context.Background(), "hash1", types.GasOracleImported, "txhash1")
+	assert.NoError(t, err)
+
+	updatedBlocks, err := l1BlockOrm.GetL1Blocks(context.Background(), map[string]interface{}{})
+	assert.NoError(t, err)
+	assert.Len(t, updatedBlocks, 2)
+	assert.Equal(t, types.GasOracleImported, types.GasOracleStatus(updatedBlocks[0].GasOracleStatus))
+	assert.Equal(t, "txhash1", updatedBlocks[0].OracleTxHash)
+}
+
 func TestL2BlockOrm(t *testing.T) {
 	sqlDB, err := db.DB()
 	assert.NoError(t, err)