From fd64f0852ca69059b1adc3fd1722f0785d38ca02 Mon Sep 17 00:00:00 2001
From: ImJeremyHe <yiliang.he@qq.com>
Date: Thu, 19 Dec 2024 11:44:11 +0800
Subject: [PATCH] escape hatch

---
 arbnode/batch_poster.go         |  2 +-
 arbnode/transaction_streamer.go | 48 +++++++--------------------------
 2 files changed, 11 insertions(+), 39 deletions(-)

diff --git a/arbnode/batch_poster.go b/arbnode/batch_poster.go
index be92708cf6..a7fdaac685 100644
--- a/arbnode/batch_poster.go
+++ b/arbnode/batch_poster.go
@@ -1423,7 +1423,7 @@ func (b *BatchPoster) maybePostSequencerBatch(ctx context.Context) (bool, error)
 
 	// Submit message positions to pending queue
 	shouldSubmit := b.streamer.shouldSubmitEspressoTransaction()
-	if (b.streamer.UseEscapeHatch && !b.streamer.EnableEscapeHatch) || shouldSubmit {
+	if shouldSubmit {
 		for p := b.building.msgCount; p < msgCount; p += 1 {
 			err = b.submitEspressoTransactionPos(p)
 			if err != nil {
diff --git a/arbnode/transaction_streamer.go b/arbnode/transaction_streamer.go
index 7b366ccbf2..73fda8d457 100644
--- a/arbnode/transaction_streamer.go
+++ b/arbnode/transaction_streamer.go
@@ -1709,7 +1709,7 @@ func (s *TransactionStreamer) submitEspressoTransactions(ctx context.Context) ti
 }
 
 // Make sure useEscapeHatch is true
-func (s *TransactionStreamer) checkEspressoLiveness(ctx context.Context) error {
+func (s *TransactionStreamer) checkEspressoLiveness() error {
 	live, err := s.lightClientReader.IsHotShotLive(s.espressoSwitchDelayThreshold)
 	if err != nil {
 		return err
@@ -1723,50 +1723,22 @@ func (s *TransactionStreamer) checkEspressoLiveness(ctx context.Context) error {
 		return nil
 	}
 
-	// If hotshot was previously up, now it is down
-	if !live {
-		log.Warn("enabling the escape hatch, hotshot is down")
-		s.EnableEscapeHatch = true
-	}
-
-	// Check if the submitted transaction should skip the espresso verification
-	submittedHash, err := s.getEspressoSubmittedHash()
-	if err != nil {
-		return err
-	}
-
-	// No transaction is waiting for espresso finalization
-	if submittedHash == nil {
+	// If escape hatch is disabled, hotshot is live, everything is fine
+	if live {
 		return nil
 	}
 
-	// If a submitted transaction is waiting for being finalized, check if hotshot is live at
-	// the corresponding L1 height.
-	data, err := s.espressoClient.FetchTransactionByHash(ctx, submittedHash)
-	if err != nil {
-		return err
-	}
+	// If escape hatch is on, and hotshot is down
+	log.Warn("enabling the escape hatch, hotshot is down")
+	s.EnableEscapeHatch = true
 
-	header, err := s.espressoClient.FetchHeaderByHeight(ctx, data.BlockHeight)
-	if err != nil {
-		return err
-	}
-
-	l1Height := header.Header.GetL1Head()
-	hotshotLive, err := s.lightClientReader.IsHotShotLiveAtHeight(l1Height, s.espressoSwitchDelayThreshold)
-	if err != nil {
-		return err
-	}
-	if hotshotLive {
-		// This transaction will be still finalized
-		return nil
-	}
+	// Skip the espresso verification for the submitted messages
 	submitted, err := s.getEspressoSubmittedPos()
 	if err != nil {
 		return err
 	}
 	if len(submitted) == 0 {
-		return fmt.Errorf("submitted messages should not have the length of 0")
+		return nil
 	}
 
 	last := submitted[len(submitted)-1]
@@ -1809,7 +1781,7 @@ func (s *TransactionStreamer) espressoSwitch(ctx context.Context, ignored struct
 	retryRate := s.espressoTxnsPollingInterval * 50
 	var err error
 	if s.UseEscapeHatch {
-		err = s.checkEspressoLiveness(ctx)
+		err = s.checkEspressoLiveness()
 		if err != nil {
 			if ctx.Err() != nil {
 				return 0
@@ -1840,7 +1812,7 @@ func (s *TransactionStreamer) espressoSwitch(ctx context.Context, ignored struct
 }
 
 func (s *TransactionStreamer) shouldSubmitEspressoTransaction() bool {
-	return !(s.UseEscapeHatch && s.EnableEscapeHatch)
+	return !s.EnableEscapeHatch
 }
 
 func (s *TransactionStreamer) Start(ctxIn context.Context) error {