JSONRPC: add id argument to listpeers.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

contrib/pylightning/lightning/lightning.py

@@ -79,13 +79,12 @@ class LightningRpc(UnixDomainSocketRpc):
         """Get info about a specific peer, optionally with its log.
         """
         if log_level:
-            peers = self.listpeers(log_level)['peers']
+            peers = self.listpeers(peer_id, log_level)['peers']
         else:
-            peers = self.listpeers()['peers']
-        for p in peers:
-            if p['peerid'] == peer_id:
-                return p
-        return None
+            peers = self.listpeers(peer_id)['peers']
+        if len(peers) == 0:
+            return None
+        return peers[0]
 
     def getlog(self, level=None):
         args = []

gossipd/gossip.c

@@ -1733,11 +1733,14 @@ static struct io_plan *get_peers(struct io_conn *conn,
 	size_t n = 0;
 	struct pubkey *id = tal_arr(conn, struct pubkey, n);
 	struct wireaddr *wireaddr = tal_arr(conn, struct wireaddr, n);
+	struct pubkey *specific_id = NULL;
 
-	if (!fromwire_gossip_getpeers_request(msg, NULL))
+	if (!fromwire_gossip_getpeers_request(msg, msg, NULL, &specific_id))
 		master_badmsg(WIRE_GOSSIPCTL_PEER_ADDRHINT, msg);
 
 	list_for_each(&daemon->peers, peer, list) {
+		if (specific_id && !pubkey_eq(specific_id, &peer->id))
+			continue;
 		tal_resize(&id, n+1);
 		tal_resize(&wireaddr, n+1);
 

gossipd/gossip_wire.csv

@@ -135,6 +135,9 @@ gossip_resolve_channel_reply,,keys,num_keys*struct pubkey
 
 # The main daemon asks for peers
 gossip_getpeers_request,3011
+# 0 or 1
+gossip_getpeers_request,,num,u16
+gossip_getpeers_request,,id,num*struct pubkey
 
 gossip_getpeers_reply,3111
 gossip_getpeers_reply,,num,u16

lightningd/peer_control.c

@@ -790,6 +790,8 @@ struct getpeers_args {
 	struct command *cmd;
 	/* If non-NULL, they want logs too */
 	enum log_level *ll;
+	/* If set, only report on a specific id. */
+	struct pubkey *specific_id;
 };
 
 static void gossipd_getpeers_complete(struct subd *gossip, const u8 *msg,
@@ -811,6 +813,9 @@ static void gossipd_getpeers_complete(struct subd *gossip, const u8 *msg,
 	json_object_start(response, NULL);
 	json_array_start(response, "peers");
 	list_for_each(&gpa->cmd->ld->peers, p, list) {
+		if (gpa->specific_id && !pubkey_eq(gpa->specific_id, &p->id))
+			continue;
+
 		json_object_start(response, NULL);
 		json_add_string(response, "state", peer_state_name(p->state));
 		json_array_start(response, "netaddr");
@@ -874,13 +879,27 @@ static void json_listpeers(struct command *cmd,
 {
 	jsmntok_t *leveltok;
 	struct getpeers_args *gpa = tal(cmd, struct getpeers_args);
+	jsmntok_t *idtok;
 
 	gpa->cmd = cmd;
-	if (!json_get_params(buffer, params, "?level", &leveltok, NULL)) {
+	gpa->specific_id = NULL;
+	if (!json_get_params(buffer, params,
+			     "?id", &idtok,
+			     "?level", &leveltok,
+			     NULL)) {
 		command_fail(cmd, "Invalid arguments");
 		return;
 	}
 
+	if (idtok) {
+		gpa->specific_id = tal_arr(cmd, struct pubkey, 1);
+		if (!json_tok_pubkey(buffer, idtok, gpa->specific_id)) {
+			command_fail(cmd, "id %.*s not valid",
+				     idtok->end - idtok->start,
+				     buffer + idtok->start);
+			return;
+		}
+	}
 	if (leveltok) {
 		gpa->ll = tal(gpa, enum log_level);
 		if (json_tok_streq(buffer, leveltok, "debug"))
@@ -900,7 +919,7 @@ static void json_listpeers(struct command *cmd,
 
 	/* Get peers from gossipd. */
 	subd_req(cmd, cmd->ld->gossip,
-		 take(towire_gossip_getpeers_request(cmd)),
+		 take(towire_gossip_getpeers_request(cmd, gpa->specific_id)),
 		 -1, 0, gossipd_getpeers_complete, gpa);
 	command_still_pending(cmd);
 }