for PhantomRouteHints { channels, phantom_scid, real_node_pubkey } in phantom_route_hints {
log_trace!(logger, "Generating phantom route hints for node {}",
log_pubkey!(real_node_pubkey));
- let mut route_hints = filter_channels(channels, amt_msat, &logger);
+ let mut route_hints = sort_and_filter_channels(channels, amt_msat, &logger);
- // If we have any public channel, the route hints from `filter_channels` will be empty.
- // In that case we create a RouteHint on which we will push a single hop with the phantom
- // route into the invoice, and let the sender find the path to the `real_node_pubkey`
+ // If we have any public channel, the route hints from `sort_and_filter_channels` will be
+ // empty. In that case we create a RouteHint on which we will push a single hop with the
+ // phantom route into the invoice, and let the sender find the path to the `real_node_pubkey`
// node by looking at our public channels.
if route_hints.is_empty() {
route_hints.push(RouteHint(vec![]))
invoice = invoice.amount_milli_satoshis(amt);
}
- let route_hints = filter_channels(channels, amt_msat, &logger);
+ let route_hints = sort_and_filter_channels(channels, amt_msat, &logger);
for hint in route_hints {
invoice = invoice.private_route(hint);
}
}
}
-/// Filters the `channels` for an invoice, and returns the corresponding `RouteHint`s to include
+/// Sorts and filters the `channels` for an invoice, and returns the corresponding `RouteHint`s to include
/// in the invoice.
///
/// The filtering is based on the following criteria:
/// * If any public, announced, channel exists (i.e. a channel with 7+ confs, to ensure the
/// announcement has had a chance to propagate), no [`RouteHint`]s will be returned, as the
/// sender is expected to find the path by looking at the public channels instead.
-fn filter_channels<L: Deref>(
+/// * Limited to a total of 3 channels.
+/// * Sorted by lowest inbound capacity if an online channel with the minimum amount requested exists,
+/// otherwise sort by highest inbound capacity to give the payment the best chance of succeeding.
+fn sort_and_filter_channels<L: Deref>(
channels: Vec<ChannelDetails>, min_inbound_capacity_msat: Option<u64>, logger: &L
) -> Vec<RouteHint> where L::Target: Logger {
let mut filtered_channels: HashMap<PublicKey, ChannelDetails> = HashMap::new();
// the payment value and where we're currently connected to the channel counterparty.
// Even if we cannot satisfy both goals, always ensure we include *some* hints, preferring
// those which meet at least one criteria.
- filtered_channels
+ let mut eligible_channels = filtered_channels
.into_iter()
.map(|(_, channel)| channel)
.filter(|channel| {
include_channel
})
- .map(route_hint_from_channel)
- .collect::<Vec<RouteHint>>()
+ .collect::<Vec<ChannelDetails>>();
+
+ eligible_channels.sort_unstable_by(|a, b| {
+ if online_min_capacity_channel_exists {
+ a.inbound_capacity_msat.cmp(&b.inbound_capacity_msat)
+ } else {
+ b.inbound_capacity_msat.cmp(&a.inbound_capacity_msat)
+ }});
+ eligible_channels.into_iter().take(3).map(route_hint_from_channel).collect::<Vec<RouteHint>>()
}
/// prefer_current_channel chooses a channel to use for route hints between a currently selected and candidate
match_invoice_routes(Some(1_000_000_000), &nodes[0], scid_aliases);
}
+ #[test]
+ fn test_insufficient_inbound_sort_by_highest_capacity() {
+ let chanmon_cfgs = create_chanmon_cfgs(5);
+ let node_cfgs = create_node_cfgs(5, &chanmon_cfgs);
+ let node_chanmgrs = create_node_chanmgrs(5, &node_cfgs, &[None, None, None, None, None]);
+ let nodes = create_network(5, &node_cfgs, &node_chanmgrs);
+ let _chan_1_0 = create_unannounced_chan_between_nodes_with_value(&nodes, 1, 0, 100_000, 0);
+ let chan_2_0 = create_unannounced_chan_between_nodes_with_value(&nodes, 2, 0, 200_000, 0);
+ let chan_3_0 = create_unannounced_chan_between_nodes_with_value(&nodes, 3, 0, 300_000, 0);
+ let chan_4_0 = create_unannounced_chan_between_nodes_with_value(&nodes, 4, 0, 400_000, 0);
+
+ // When no single channel has enough inbound capacity for the payment, we expect the three
+ // highest inbound channels to be chosen.
+ let mut scid_aliases = HashSet::new();
+ scid_aliases.insert(chan_2_0.0.short_channel_id_alias.unwrap());
+ scid_aliases.insert(chan_3_0.0.short_channel_id_alias.unwrap());
+ scid_aliases.insert(chan_4_0.0.short_channel_id_alias.unwrap());
+
+ match_invoice_routes(Some(1_000_000_000), &nodes[0], scid_aliases.clone());
+ }
+
+ #[test]
+ fn test_sufficient_inbound_sort_by_lowest_capacity() {
+ let chanmon_cfgs = create_chanmon_cfgs(5);
+ let node_cfgs = create_node_cfgs(5, &chanmon_cfgs);
+ let node_chanmgrs = create_node_chanmgrs(5, &node_cfgs, &[None, None, None, None, None]);
+ let nodes = create_network(5, &node_cfgs, &node_chanmgrs);
+ let chan_1_0 = create_unannounced_chan_between_nodes_with_value(&nodes, 1, 0, 100_000, 0);
+ let chan_2_0 = create_unannounced_chan_between_nodes_with_value(&nodes, 2, 0, 200_000, 0);
+ let chan_3_0 = create_unannounced_chan_between_nodes_with_value(&nodes, 3, 0, 300_000, 0);
+ let _chan_4_0 = create_unannounced_chan_between_nodes_with_value(&nodes, 4, 0, 400_000, 0);
+
+ // When we have channels that have sufficient inbound for the payment, test that we sort
+ // by lowest inbound capacity.
+ let mut scid_aliases = HashSet::new();
+ scid_aliases.insert(chan_1_0.0.short_channel_id_alias.unwrap());
+ scid_aliases.insert(chan_2_0.0.short_channel_id_alias.unwrap());
+ scid_aliases.insert(chan_3_0.0.short_channel_id_alias.unwrap());
+
+ match_invoice_routes(Some(50_000_000), &nodes[0], scid_aliases.clone());
+ }
+
#[test]
fn test_forwarding_info_not_assigned_channel_excluded_from_hints() {
let chanmon_cfgs = create_chanmon_cfgs(3);
projects / rust-lightning / commitdiff