wip

Author: joostjager

lightning/src/routing/scoring.rs

@@ -477,6 +477,19 @@ where L::Target: Logger {
 	channel_liquidities: HashMap<u64, ChannelLiquidity>,
 }
 
+pub struct ChannelLiquidities(HashMap<u64, ChannelLiquidity>);
+
+impl Readable for ChannelLiquidities {
+	#[inline]
+	fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
+		let mut channel_liquidities = new_hash_map();
+		read_tlv_fields!(r, {
+			(0, channel_liquidities, required),
+		});
+		Ok(ChannelLiquidities(channel_liquidities))
+	}
+}
+
 /// Parameters for configuring [`ProbabilisticScorer`].
 ///
 /// Used to configure base, liquidity, and amount penalties, the sum of which comprises the channel
@@ -804,7 +817,7 @@ impl ProbabilisticScoringDecayParameters {
 /// first node in the ordering of the channel's counterparties. Thus, swapping the two liquidity
 /// offset fields gives the opposite direction.
 #[repr(C)] // Force the fields in memory to be in the order we specify
-struct ChannelLiquidity {
+pub struct ChannelLiquidity {
 	/// Lower channel liquidity bound in terms of an offset from zero.
 	min_liquidity_offset_msat: u64,
 
@@ -814,7 +827,7 @@ struct ChannelLiquidity {
 	liquidity_history: HistoricalLiquidityTracker,
 
 	/// Time when either liquidity bound was last modified as an offset since the unix epoch.
-	last_updated: Duration,
+	pub last_updated: Duration,
 
 	/// Time when the historical liquidity bounds were last modified as an offset against the unix
 	/// epoch.
@@ -853,6 +866,21 @@ impl<G: Deref<Target = NetworkGraph<L>>, L: Deref> ProbabilisticScorer<G, L> whe
 		}
 	}
 
+	/// Merge external channel liquidity data into the internal state.
+	pub fn merge(&mut self, other: ChannelLiquidities) {
+
+		let channel_liquidities = &mut self.channel_liquidities;
+
+		for (id, item) in other.0 {
+			match channel_liquidities.get_mut(&id) {
+				None => { channel_liquidities.insert(id, item); },
+				Some(current) => {
+					current.merge(&item);
+				}
+			}
+		}
+	}
+
 	#[cfg(test)]
 	fn with_channel(mut self, short_channel_id: u64, liquidity: ChannelLiquidity) -> Self {
 		assert!(self.channel_liquidities.insert(short_channel_id, liquidity).is_none());
@@ -1074,6 +1102,12 @@ impl ChannelLiquidity {
 		}
 	}
 
+	fn merge(&mut self, other: &Self) {
+		self.liquidity_history.merge(&other.liquidity_history);
+
+		// TODO: Merge other fields.
+	}
+
 	/// Returns a view of the channel liquidity directed from `source` to `target` assuming
 	/// `capacity_msat`.
 	fn as_directed(
@@ -1805,6 +1839,13 @@ mod bucketed_history {
 				self.buckets[bucket] = self.buckets[bucket].saturating_add(BUCKET_FIXED_POINT_ONE);
 			}
 		}
+
+		/// Returns the average of the buckets between the two trackers.
+		pub(crate) fn merge(&mut self, other: &Self) -> () {
+			for (index, bucket) in self.buckets.iter_mut().enumerate() {
+				*bucket = (*bucket + other.buckets[index]) / 2;
+			}
+		}
 	}
 
 	impl_writeable_tlv_based!(HistoricalBucketRangeTracker, { (0, buckets, required) });
@@ -1901,6 +1942,12 @@ mod bucketed_history {
 		-> DirectedHistoricalLiquidityTracker<&'a mut HistoricalLiquidityTracker> {
 			DirectedHistoricalLiquidityTracker { source_less_than_target, tracker: self }
 		}
+
+		pub fn merge(&mut self, other: &Self) {
+			self.min_liquidity_offset_history.merge(&other.min_liquidity_offset_history);
+			self.max_liquidity_offset_history.merge(&other.max_liquidity_offset_history);
+			self.recalculate_valid_point_count();
+		}
 	}
 
 	/// A set of buckets representing the history of where we've seen the minimum- and maximum-