listchannels: allow source arg to list channels by their source node.

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

CHANGELOG.md

@@ -13,6 +13,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 - lightning-cli: `help <cmd>` finds man pages even if `make install` not run.
 - JSON API: `waitsendpay` now has an `erring_channel_direction` field.
 - JSON API: `listpeers` now has a `channel_direction` field in `channels`.
+- JSON API: `listchannels` now takes a `source` option to filter by node id.
 
 ### Changed
 

contrib/pylightning/lightning/lightning.py

@@ -167,12 +167,13 @@ class LightningRpc(UnixDomainSocketRpc):
         }
         return self.call("getroute", payload)
 
-    def listchannels(self, short_channel_id=None):
+    def listchannels(self, short_channel_id=None, source=None):
         """
-        Show all known channels, accept optional {short_channel_id}
+        Show all known channels, accept optional {short_channel_id} or {source}
         """
         payload = {
-            "short_channel_id": short_channel_id
+            "short_channel_id": short_channel_id,
+            "source": source
         }
         return self.call("listchannels", payload)
 

doc/lightning-listchannels.7

@@ -2,12 +2,12 @@
 .\"     Title: lightning-listchannels
 .\"    Author: [see the "AUTHOR" section]
 .\" Generator: DocBook XSL Stylesheets v1.79.1 <http://docbook.sf.net/>
-.\"      Date: 01/08/2019
+.\"      Date: 01/09/2019
 .\"    Manual: \ \&
 .\"    Source: \ \&
 .\"  Language: English
 .\"
-.TH "LIGHTNING\-LISTCHANN" "7" "01/08/2019" "\ \&" "\ \&"
+.TH "LIGHTNING\-LISTCHANN" "7" "01/09/2019" "\ \&" "\ \&"
 .\" -----------------------------------------------------------------
 .\" * Define some portability stuff
 .\" -----------------------------------------------------------------
@@ -31,14 +31,16 @@
 lightning-listchannels \- Command to query active lightning channels in the entire network\&.
 .SH "SYNOPSIS"
 .sp
-\fBlistchannels\fR [\fIshort_channel_id\fR]
+\fBlistchannels\fR [\fIshort_channel_id\fR] [\fIsource\fR]
 .SH "DESCRIPTION"
 .sp
 The \fBlistchannels\fR RPC command returns data on channels that are known to the node\&. Because channels may be bidirectional, up to 2 objects will be returned for each channel (one for each direction)\&.
 .sp
-If no \fIshort_channel_id\fR is supplied, then data on all lightning channels known to this node, are returned\&. These can be local channels or public channels broadcast on the gossip network\&.
+If \fIshort_channel_id\fR is supplied, then only known channels with a matching \fIshort_channel_id\fR are returned\&.
 .sp
-Supplying \fIshort_channel_id\fR will filter the results to only return data for known channels with a matching \fIshort_channel_id\fR\&.
+If \fIsource\fR is supplied, then only channels leading from that node id are returned\&.
+.sp
+If neither is supplied, data on all lightning channels known to this node, are returned\&. These can be local channels or public channels broadcast on the gossip network\&.
 .SH "RETURN VALUE"
 .sp
 On success, an object with a "channels" key is returned containing a list of 0 or more objects\&.
@@ -191,7 +193,7 @@ message (BOLT #7)\&.
 : The number of blocks delay required to wait for on\-chain settlement when unilaterally closing the channel (BOLT #2)\&.
 .RE
 .sp
-If \fIshort_channel_id\fR is supplied and no matching channels are found, a "channels" object with an empty list is returned\&.
+If \fIshort_channel_id\fR or \fIsource\fR is supplied and no matching channels are found, a "channels" object with an empty list is returned\&.
 .SH "ERRORS"
 .sp
 If \fIshort_channel_id\fR is not a valid short_channel_id, an error message will be returned:
@@ -206,12 +208,14 @@ If \fIshort_channel_id\fR is not a valid short_channel_id, an error message will
 .if n \{\
 .RE
 .\}
+.sp
+Similarly if \fIsource\fR is not a valid pubkey\&.
 .SH "AUTHOR"
 .sp
 Michael Hawkins <michael\&.hawkins@protonmail\&.com>\&.
 .SH "SEE ALSO"
 .sp
-lightning\-fundchannel(7)
+lightning\-fundchannel(7), lightning\-listnodes(7)
 .SH "RESOURCES"
 .sp
 Main web site: https://github\&.com/ElementsProject/lightning

doc/lightning-listchannels.7.txt

@@ -8,7 +8,7 @@ lightning-listchannels - Command to query active lightning channels in the entir
 
 SYNOPSIS
 --------
-*listchannels* ['short_channel_id']
+*listchannels* ['short_channel_id'] ['source']
 
 DESCRIPTION
 -----------
@@ -16,12 +16,15 @@ The *listchannels* RPC command returns data on channels that are known to the
 node.  Because channels may be bidirectional, up to 2 objects will be returned
 for each channel (one for each direction).
 
-If no 'short_channel_id' is supplied, then data on all lightning channels known
-to this node, are returned.  These can be local channels or public channels
-broadcast on the gossip network.
+If 'short_channel_id' is supplied, then only known channels with a
+matching 'short_channel_id' are returned.
 
-Supplying 'short_channel_id' will filter the results to only return data for 
-known channels with a matching 'short_channel_id'.
+If 'source' is supplied, then only channels leading from that node id
+are returned.
+
+If neither is supplied, data on all lightning channels known to this
+node, are returned.  These can be local channels or public channels
+broadcast on the gossip network.
 
 RETURN VALUE
 ------------
@@ -56,8 +59,8 @@ transferred satoshi (BOLT #2).
 - 'delay' : The number of blocks delay required to wait for on-chain settlement
 when unilaterally closing the channel (BOLT #2).
 
-If 'short_channel_id' is supplied and no matching channels are found, a
-"channels" object with an empty list is returned.
+If 'short_channel_id' or 'source' is supplied and no matching channels
+are found, a "channels" object with an empty list is returned.
 
 ERRORS
 ------
@@ -69,13 +72,15 @@ returned:
   "message" : "'short_channel_id' should be a short channel id, not '...'" }
 ----
 
+Similarly if 'source' is not a valid pubkey.
+
 AUTHOR
 ------
 Michael Hawkins <michael.hawkins@protonmail.com>.
 
 SEE ALSO
 --------
-lightning-fundchannel(7)
+lightning-fundchannel(7), lightning-listnodes(7)
 
 RESOURCES
 ---------

gossipd/gossip_wire.csv

@@ -43,6 +43,7 @@ gossip_getroute_reply,,hops,num_hops*struct route_hop
 
 gossip_getchannels_request,3007
 gossip_getchannels_request,,short_channel_id,?struct short_channel_id
+gossip_getchannels_request,,source,?struct pubkey
 
 gossip_getchannels_reply,3107
 gossip_getchannels_reply,,num_channels,u16

gossipd/gossipd.c

@@ -1971,9 +1971,10 @@ static struct io_plan *getchannels_req(struct io_conn *conn,
 	struct gossip_getchannels_entry *entries;
 	struct chan *chan;
 	struct short_channel_id *scid;
+	struct pubkey *source;
 
 	/* Note: scid is marked optional in gossip_wire.csv */
-	if (!fromwire_gossip_getchannels_request(msg, msg, &scid))
+	if (!fromwire_gossip_getchannels_request(msg, msg, &scid, &source))
 		master_badmsg(WIRE_GOSSIP_GETCHANNELS_REQUEST, msg);
 
 	entries = tal_arr(tmpctx, struct gossip_getchannels_entry, 0);
@@ -1982,6 +1983,15 @@ static struct io_plan *getchannels_req(struct io_conn *conn,
 		chan = get_channel(daemon->rstate, scid);
 		if (chan)
 			append_channel(&entries, chan);
+	} else if (source) {
+		struct node *s = get_node(daemon->rstate, source);
+		if (s) {
+			for (size_t i = 0; i < tal_count(s->chans); i++)
+				append_half_channel(&entries,
+						    s->chans[i],
+						    !half_chan_to(s,
+								  s->chans[i]));
+		}
 	} else {
 		u64 idx;
 

lightningd/gossip_control.c

@@ -453,12 +453,18 @@ static struct command_result *json_listchannels(struct command *cmd,
 {
 	u8 *req;
 	struct short_channel_id *id;
+	struct pubkey *source;
+
 	if (!param(cmd, buffer, params,
 		   p_opt("short_channel_id", param_short_channel_id, &id),
+		   p_opt("source", param_pubkey, &source),
 		   NULL))
 		return command_param_failed();
 
-	req = towire_gossip_getchannels_request(cmd, id);
+	if (id && source)
+		return command_fail(cmd, JSONRPC2_INVALID_PARAMS,
+				    "Cannot specify both source and short_channel_id");
+	req = towire_gossip_getchannels_request(cmd, id, source);
 	subd_req(cmd->ld->gossip, cmd->ld->gossip,
 		 req, -1, 0, json_listchannels_reply, cmd);
 	return command_still_pending(cmd);
@@ -467,7 +473,7 @@ static struct command_result *json_listchannels(struct command *cmd,
 static const struct json_command listchannels_command = {
 	"listchannels",
 	json_listchannels,
-	"Show channel {short_channel_id} (or all known channels, if no {short_channel_id})"
+	"Show channel {short_channel_id} or {source} (or all known channels, if not specified)"
 };
 AUTODATA(json_command, &listchannels_command);
 

tests/test_gossip.py

@@ -277,6 +277,15 @@ def test_gossip_jsonrpc(node_factory):
     assert len([c for c in channels1 if not c['public']]) == 2
     assert len([c for c in channels2 if not c['public']]) == 2
 
+    # Test listchannels-by-source
+    channels1 = l1.rpc.listchannels(source=l1.info['id'])['channels']
+    channels2 = l2.rpc.listchannels(source=l1.info['id'])['channels']
+    assert only_one(channels1)['source'] == l1.info['id']
+    assert only_one(channels1)['destination'] == l2.info['id']
+    assert channels1 == channels2
+
+    channels2 = l2.rpc.listchannels()['channels']
+
     # Now proceed to funding-depth and do a full gossip round
     l1.bitcoin.generate_block(5)
     # Could happen in either order.