From 94504a9d411fd0eaf49cffe60739248cc81e0871 Mon Sep 17 00:00:00 2001
From: Olaoluwa Osuntokun <laolu32@gmail.com>
Date: Tue, 16 Jan 2018 19:57:04 -0800
Subject: [PATCH] breacharbiter: notify the ChainArbitrator of fresh signals
 for a channel on startup

---
 breacharbiter.go      | 17 +++++++++++++++++
 breacharbiter_test.go | 22 ++++++++++++++--------
 2 files changed, 31 insertions(+), 8 deletions(-)

diff --git a/breacharbiter.go b/breacharbiter.go
index 07f395afc..3f9b67cb9 100644
--- a/breacharbiter.go
+++ b/breacharbiter.go
@@ -45,6 +45,14 @@ type BreachConfig struct {
 	// a close type to be included in the channel close summary.
 	CloseLink func(*wire.OutPoint, htlcswitch.ChannelCloseType)
 
+	// UpdateCloseSignal allows the breach arbiter to notify the
+	// ChainArbitrator that a set of new signals for the unilateral closing
+	// of a channel is now available. This ensures that ifa channel hasn't
+	// had any updates since it was live, then we're still able to act on
+	// on-chain events.
+	UpdateCloseSignal func(*wire.OutPoint,
+		chan *lnwallet.UnilateralCloseSummary) error
+
 	// DB provides access to the user's channels, allowing the breach
 	// arbiter to determine the current state of a user's channels, and how
 	// it should respond to channel closure.
@@ -306,6 +314,15 @@ func (b *breachArbiter) contractObserver(
 		chanPoint := channel.ChanPoint
 		b.breachObservers[*chanPoint] = settleSignal
 
+		// Before we'll launch our breach observe, we'll send this
+		// latest set of contract signals to the ChainArbitrator.
+		//
+		// TODO(roasbeef): just move now?
+		err := b.cfg.UpdateCloseSignal(chanPoint, channel.UnilateralClose)
+		if err != nil {
+			brarLog.Errorf("unable to update close signals: %v", err)
+		}
+
 		b.wg.Add(1)
 		go b.breachObserver(channel, settleSignal)
 	}
diff --git a/breacharbiter_test.go b/breacharbiter_test.go
index 828ab7d7c..0ac857951 100644
--- a/breacharbiter_test.go
+++ b/breacharbiter_test.go
@@ -1097,10 +1097,9 @@ func TestBreachHandoffFail(t *testing.T) {
 	aliceKeyPriv, _ := btcec.PrivKeyFromBytes(btcec.S256(),
 		alicesPrivKey)
 	aliceSigner := &mockSigner{aliceKeyPriv}
-	estimator := &lnwallet.StaticFeeEstimator{FeeRate: 50}
 
 	alice2, err := lnwallet.NewLightningChannel(aliceSigner, notifier,
-		estimator, alice.State())
+		nil, alice.State())
 	if err != nil {
 		t.Fatalf("unable to create test channels: %v", err)
 	}
@@ -1382,16 +1381,23 @@ func createInitChannelsWithNotifier(revocationWindow int,
 		Db:                      dbBob,
 	}
 
+	pCache := &mockPreimageCache{
+		// hash -> preimage
+		preimageMap: make(map[[32]byte][]byte),
+	}
+
 	aliceSigner := &mockSigner{aliceKeyPriv}
 	bobSigner := &mockSigner{bobKeyPriv}
 
-	channelAlice, err := lnwallet.NewLightningChannel(aliceSigner, notifier,
-		estimator, aliceChannelState)
+	channelAlice, err := lnwallet.NewLightningChannel(
+		aliceSigner, notifier, pCache, aliceChannelState,
+	)
 	if err != nil {
 		return nil, nil, nil, err
 	}
-	channelBob, err := lnwallet.NewLightningChannel(bobSigner, notifier,
-		estimator, bobChannelState)
+	channelBob, err := lnwallet.NewLightningChannel(
+		bobSigner, notifier, pCache, bobChannelState,
+	)
 	if err != nil {
 		return nil, nil, nil, err
 	}
@@ -1476,7 +1482,7 @@ func forceStateTransition(chanA, chanB *lnwallet.LightningChannel) error {
 		return err
 	}
 
-	bobRevocation, err := chanB.RevokeCurrentCommitment()
+	bobRevocation, _, err := chanB.RevokeCurrentCommitment()
 	if err != nil {
 		return err
 	}
@@ -1492,7 +1498,7 @@ func forceStateTransition(chanA, chanB *lnwallet.LightningChannel) error {
 		return err
 	}
 
-	aliceRevocation, err := chanA.RevokeCurrentCommitment()
+	aliceRevocation, _, err := chanA.RevokeCurrentCommitment()
 	if err != nil {
 		return err
 	}