lightningd: Fix channel-persistence for channels with commits

I was hoping to defer HTLC updates until we actually store HTLCs, but
we need to flush to DB whenever balances update as well.

Signed-off-by: Christian Decker <decker.christian@gmail.com>

lightningd/peer_htlcs.c

@@ -887,6 +887,10 @@ static bool peer_save_commitsig_received(struct peer *peer, u64 commitnum)
 	peer->next_index[LOCAL]++;
 
 	/* FIXME: Save to database, with sig and HTLCs. */
+	if (!wallet_channel_save(peer->ld->wallet, peer->channel)) {
+		fatal("Could not save channel to database: %s",
+		      peer->ld->wallet->db->err);
+	}
 	return true;
 }
 
@@ -903,6 +907,11 @@ static bool peer_save_commitsig_sent(struct peer *peer, u64 commitnum)
 	peer->next_index[REMOTE]++;
 
 	/* FIXME: Save to database, with sig and HTLCs. */
+	if (!wallet_channel_save(peer->ld->wallet, peer->channel)) {
+		fatal("Could not save channel to database: %s",
+		      peer->ld->wallet->db->err);
+	}
+
 	return true;
 }
 
@@ -1207,6 +1216,11 @@ int peer_got_revoke(struct peer *peer, const u8 *msg)
 		hin = find_htlc_in(&peer->ld->htlcs_in, peer, changed[i].id);
 		local_fail_htlc(hin, failcodes[i]);
 	}
+	if (!wallet_channel_save(peer->ld->wallet, peer->channel)) {
+		fatal("Could not save channel to database: %s",
+		      peer->ld->wallet->db->err);
+	}
+
 	return 0;
 }
 

tests/test_lightningd.py

@@ -1022,11 +1022,17 @@ class LightningDTests(BaseLightningDTests):
         for n in (l1, l2):
             assert(n.db_query('SELECT COUNT(id) as count FROM channels;')[0]['count'] == 1)
 
+        # Perform a payment so we have something to restore
+        self.pay(l1, l2, 10000)
+        time.sleep(1)
+        assert l1.rpc.getpeers()['peers'][0]['msatoshi_to_us'] == 99990000
+        assert l2.rpc.getpeers()['peers'][0]['msatoshi_to_us'] == 10000
+
+        # Stop l2, l1 will reattempt to connect
         l2.daemon.stop()
 
-        # Let the other side notice, then stop it
+        # Wait for l1 to notice
         wait_for(lambda: not l1.rpc.getpeers()['peers'][0]['connected'])
-        #l1.daemon.stop()
 
         # Now restart l1 and it should reload peers/channels from the DB
         l2.daemon.start()
@@ -1037,6 +1043,14 @@ class LightningDTests(BaseLightningDTests):
 
         # Now make sure this is really functional by sending a payment
         self.pay(l1, l2, 10000)
+        time.sleep(1)
+        assert l1.rpc.getpeers()['peers'][0]['msatoshi_to_us'] == 99980000
+        assert l2.rpc.getpeers()['peers'][0]['msatoshi_to_us'] == 20000
+
+        # Finally restart l1, and make sure it remembers
+        l1.daemon.stop()
+        l1.daemon.start()
+        assert l1.rpc.getpeers()['peers'][0]['msatoshi_to_us'] == 99980000
 
 class LegacyLightningDTests(BaseLightningDTests):
 

tests/utils.py

@@ -61,6 +61,8 @@ class TailableProc(object):
     def stop(self):
         self.proc.terminate()
         self.proc.kill()
+        self.proc.wait()
+        self.thread.join()
         if self.outputDir:
             logpath = os.path.join(self.outputDir, 'log')
             with open(logpath, 'w') as f: