From a9f93b29889a60295d344532fe7d47c1ef0d4031 Mon Sep 17 00:00:00 2001
From: "Johan T. Halseth" <johanth@gmail.com>
Date: Tue, 20 Nov 2018 15:09:45 +0100
Subject: [PATCH] contractcourt/chain_watcher: add channel sync message to
 CloseChannelSummary

---
 contractcourt/chain_watcher.go | 27 +++++++++++++++++++++++++++
 lnwallet/channel.go            |  9 +++++++++
 2 files changed, 36 insertions(+)

diff --git a/contractcourt/chain_watcher.go b/contractcourt/chain_watcher.go
index c183788f..2d60b782 100644
--- a/contractcourt/chain_watcher.go
+++ b/contractcourt/chain_watcher.go
@@ -522,6 +522,15 @@ func (c *chainWatcher) dispatchCooperativeClose(commitSpend *chainntnfs.SpendDet
 		LocalChanConfig:         c.cfg.chanState.LocalChanCfg,
 	}
 
+	// Attempt to add a channel sync message to the close summary.
+	chanSync, err := lnwallet.ChanSyncMsg(c.cfg.chanState)
+	if err != nil {
+		log.Errorf("ChannelPoint(%v): unable to create channel sync "+
+			"message: %v", c.cfg.chanState.FundingOutpoint, err)
+	} else {
+		closeSummary.LastChanSyncMsg = chanSync
+	}
+
 	// Create a summary of all the information needed to handle the
 	// cooperative closure.
 	closeInfo := &CooperativeCloseInfo{
@@ -590,6 +599,15 @@ func (c *chainWatcher) dispatchLocalForceClose(
 		closeSummary.TimeLockedBalance += htlcValue
 	}
 
+	// Attempt to add a channel sync message to the close summary.
+	chanSync, err := lnwallet.ChanSyncMsg(c.cfg.chanState)
+	if err != nil {
+		log.Errorf("ChannelPoint(%v): unable to create channel sync "+
+			"message: %v", c.cfg.chanState.FundingOutpoint, err)
+	} else {
+		closeSummary.LastChanSyncMsg = chanSync
+	}
+
 	// With the event processed, we'll now notify all subscribers of the
 	// event.
 	closeInfo := &LocalUnilateralCloseInfo{
@@ -749,6 +767,15 @@ func (c *chainWatcher) dispatchContractBreach(spendEvent *chainntnfs.SpendDetail
 		LocalChanConfig:         c.cfg.chanState.LocalChanCfg,
 	}
 
+	// Attempt to add a channel sync message to the close summary.
+	chanSync, err := lnwallet.ChanSyncMsg(c.cfg.chanState)
+	if err != nil {
+		log.Errorf("ChannelPoint(%v): unable to create channel sync "+
+			"message: %v", c.cfg.chanState.FundingOutpoint, err)
+	} else {
+		closeSummary.LastChanSyncMsg = chanSync
+	}
+
 	if err := c.cfg.chanState.CloseChannel(&closeSummary); err != nil {
 		return err
 	}
diff --git a/lnwallet/channel.go b/lnwallet/channel.go
index d45ba296..ca6b2e10 100644
--- a/lnwallet/channel.go
+++ b/lnwallet/channel.go
@@ -5116,6 +5116,15 @@ func NewUnilateralCloseSummary(chanState *channeldb.OpenChannel, signer Signer,
 		LocalChanConfig:         chanState.LocalChanCfg,
 	}
 
+	// Attempt to add a channel sync message to the close summary.
+	chanSync, err := ChanSyncMsg(chanState)
+	if err != nil {
+		walletLog.Errorf("ChannelPoint(%v): unable to create channel sync "+
+			"message: %v", chanState.FundingOutpoint, err)
+	} else {
+		closeSummary.LastChanSyncMsg = chanSync
+	}
+
 	return &UnilateralCloseSummary{
 		SpendDetail:         commitSpend,
 		ChannelCloseSummary: closeSummary,