listpeers: show close_to address

If a 'upfront_shutdown_script' was specified, show the address +
scriptpubky in `listpeers`

Changelog-added: JSON API: `listpeers` channels now include `close_to` and `close_to_addr` iff a `close_to` address was specified at channel open

lightningd/peer_control.c

@@ -14,6 +14,7 @@
 #include <ccan/take/take.h>
 #include <ccan/tal/str/str.h>
 #include <channeld/gen_channel_wire.h>
+#include <common/addr.h>
 #include <common/dev_disconnect.h>
 #include <common/features.h>
 #include <common/htlc_trim.h>
@@ -619,6 +620,17 @@ static void json_add_channel(struct lightningd *ld,
 	json_add_string(response, "channel_id",
 			type_to_string(tmpctx, struct channel_id, &cid));
 	json_add_txid(response, "funding_txid", &channel->funding_txid);
+
+	if (channel->shutdown_scriptpubkey[LOCAL]) {
+		char *addr = encode_scriptpubkey_to_addr(tmpctx,
+					get_chainparams(ld),
+					channel->shutdown_scriptpubkey[LOCAL]);
+		if (addr)
+			json_add_string(response, "close_to_addr", addr);
+		json_add_hex_talarr(response, "close_to",
+				    channel->shutdown_scriptpubkey[LOCAL]);
+	}
+
 	json_add_bool(
 	    response, "private",
 	    !(channel->channel_flags & CHANNEL_FLAGS_ANNOUNCE_CHANNEL));

tests/test_connection.py

@@ -1133,12 +1133,16 @@ def _fundchannel(l1, l2, close_to):
     # check that you can provide a closing address upfront
     addr = l1.rpc.newaddr()['bech32']
     _fundchannel(l1, l2, addr)
+    # confirm that it appears in listpeers
+    assert addr == only_one(l1.rpc.listpeers()['peers'])['channels'][1]['close_to_addr']
     resp = l1.rpc.close(l2.info['id'])
     assert resp['type'] == 'mutual'
     assert only_one(only_one(bitcoind.rpc.decoderawtransaction(resp['tx'])['vout'])['scriptPubKey']['addresses']) == addr
 
     # check that passing in the same addr to close works
+    addr = bitcoind.rpc.getnewaddress()
     _fundchannel(l1, l2, addr)
+    assert addr == only_one(l1.rpc.listpeers()['peers'])['channels'][2]['close_to_addr']
     resp = l1.rpc.close(l2.info['id'], destination=addr)
     assert resp['type'] == 'mutual'
     assert only_one(only_one(bitcoind.rpc.decoderawtransaction(resp['tx'])['vout'])['scriptPubKey']['addresses']) == addr