fix(op-node): l1 client use eth_getFinalizedBlock to get finalized bl…

…ock (bnb-chain#36)

Co-authored-by: Owen <[email protected]>

op-node/sources/eth_client.go

@@ -307,6 +307,14 @@ func (s *EthClient) InfoByLabel(ctx context.Context, label eth.BlockLabel) (eth.
 	return s.headerCall(ctx, "eth_getBlockByNumber", label)
 }
 
+func (s *EthClient) BSCInfoByLabel(ctx context.Context, label eth.BlockLabel) (eth.BlockInfo, error) {
+	// can't hit the cache when querying the head due to reorgs / changes.
+	if label == eth.Finalized {
+		return s.headerCall(ctx, "eth_getFinalizedBlock", numberID(15))
+	}
+	return s.headerCall(ctx, "eth_getBlockByNumber", label)
+}
+
 func (s *EthClient) InfoAndTxsByHash(ctx context.Context, hash common.Hash) (eth.BlockInfo, types.Transactions, error) {
 	if header, ok := s.headersCache.Get(hash); ok {
 		if txs, ok := s.transactionsCache.Get(hash); ok {

op-node/sources/l1_client.go

@@ -75,7 +75,7 @@ func NewL1Client(client client.RPC, log log.Logger, metrics caching.Metrics, con
 // L1BlockRefByLabel returns the [eth.L1BlockRef] for the given block label.
 // Notice, we cannot cache a block reference by label because labels are not guaranteed to be unique.
 func (s *L1Client) L1BlockRefByLabel(ctx context.Context, label eth.BlockLabel) (eth.L1BlockRef, error) {
-	info, err := s.InfoByLabel(ctx, label)
+	info, err := s.BSCInfoByLabel(ctx, label)
 	if err != nil {
 		// Both geth and erigon like to serve non-standard errors for the safe and finalized heads, correct that.
 		// This happens when the chain just started and nothing is marked as safe/finalized yet.