From 74a2359c04f60389f2aadc4d2b82b09eedbc2e2d Mon Sep 17 00:00:00 2001
From: Svyatoslav Nikolsky <svyatonik@gmail.com>
Date: Fri, 6 Nov 2020 18:42:53 +0300
Subject: [PATCH] Print progress of message races (#489)
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* print message race progress

* fmt

* Update relays/messages-relay/src/message_race_loop.rs

Co-authored-by: Tomasz Drwięga <tomusdrw@users.noreply.github.com>

Co-authored-by: Tomasz Drwięga <tomusdrw@users.noreply.github.com>
---
 .../src/message_race_delivery.rs              |  8 +++++
 .../messages-relay/src/message_race_loop.rs   | 35 +++++++++++++++++++
 .../src/message_race_strategy.rs              | 11 ++++++
 3 files changed, 54 insertions(+)

diff --git a/bridges/relays/messages-relay/src/message_race_delivery.rs b/bridges/relays/messages-relay/src/message_race_delivery.rs
index a5d096b7710b..90345f8c6157 100644
--- a/bridges/relays/messages-relay/src/message_race_delivery.rs
+++ b/bridges/relays/messages-relay/src/message_race_delivery.rs
@@ -212,6 +212,14 @@ impl<P: MessageLane> RaceStrategy<SourceHeaderIdOf<P>, TargetHeaderIdOf<P>, P::M
 		self.strategy.is_empty()
 	}
 
+	fn best_at_source(&self) -> P::MessageNonce {
+		self.strategy.best_at_source()
+	}
+
+	fn best_at_target(&self) -> P::MessageNonce {
+		self.strategy.best_at_target()
+	}
+
 	fn source_nonces_updated(&mut self, at_block: SourceHeaderIdOf<P>, nonces: ClientNonces<P::MessageNonce>) {
 		self.source_nonces = Some(nonces.clone());
 		self.strategy.source_nonces_updated(at_block, nonces)
diff --git a/bridges/relays/messages-relay/src/message_race_loop.rs b/bridges/relays/messages-relay/src/message_race_loop.rs
index c3239f711537..43a2cd9ad275 100644
--- a/bridges/relays/messages-relay/src/message_race_loop.rs
+++ b/bridges/relays/messages-relay/src/message_race_loop.rs
@@ -117,6 +117,11 @@ pub trait RaceStrategy<SourceHeaderId, TargetHeaderId, MessageNonce, Proof> {
 
 	/// Should return true if nothing has to be synced.
 	fn is_empty(&self) -> bool;
+	/// Return best nonce at source node.
+	fn best_at_source(&self) -> MessageNonce;
+	/// Return best nonce at target node.
+	fn best_at_target(&self) -> MessageNonce;
+
 	/// Called when nonces are updated at source node of the race.
 	fn source_nonces_updated(&mut self, at_block: SourceHeaderId, nonce: ClientNonces<MessageNonce>);
 	/// Called when nonces are updated at target node of the race.
@@ -135,6 +140,7 @@ pub trait RaceStrategy<SourceHeaderId, TargetHeaderId, MessageNonce, Proof> {
 }
 
 /// State of the race.
+#[derive(Debug)]
 pub struct RaceState<SourceHeaderId, TargetHeaderId, MessageNonce, Proof> {
 	/// Source state, if known.
 	pub source_state: Option<ClientState<SourceHeaderId, TargetHeaderId>>,
@@ -161,6 +167,7 @@ pub async fn run<P: MessageRace, SC: SourceClient<P>>(
 		ProofParameters = SC::ProofParameters,
 	>,
 ) -> Result<(), FailedClient> {
+	let mut progress_context = Instant::now();
 	let mut race_state = RaceState::default();
 	let mut stall_countdown = Instant::now();
 
@@ -295,6 +302,8 @@ pub async fn run<P: MessageRace, SC: SourceClient<P>>(
 			}
 		}
 
+		progress_context = print_race_progress::<P, _>(progress_context, &strategy);
+
 		if stall_countdown.elapsed() > stall_timeout {
 			return Err(FailedClient::Both);
 		} else if race_state.nonces_to_submit.is_none() && race_state.nonces_submitted.is_none() && strategy.is_empty()
@@ -379,6 +388,32 @@ impl<SourceHeaderId, TargetHeaderId, MessageNonce, Proof> Default
 	}
 }
 
+/// Print race progress.
+fn print_race_progress<P, S>(prev_time: Instant, strategy: &S) -> Instant
+where
+	P: MessageRace,
+	S: RaceStrategy<P::SourceHeaderId, P::TargetHeaderId, P::MessageNonce, P::Proof>,
+{
+	let now_time = Instant::now();
+
+	let need_update = now_time.saturating_duration_since(prev_time) > Duration::from_secs(10);
+	if !need_update {
+		return prev_time;
+	}
+
+	let now_best_nonce_at_source = strategy.best_at_source();
+	let now_best_nonce_at_target = strategy.best_at_target();
+	log::info!(
+		target: "bridge",
+		"Synced {:?} of {:?} nonces in {} -> {} race",
+		now_best_nonce_at_target,
+		now_best_nonce_at_source,
+		P::source_name(),
+		P::target_name(),
+	);
+	now_time
+}
+
 fn select_nonces_to_deliver<SourceHeaderId, TargetHeaderId, MessageNonce, Proof, Strategy>(
 	race_state: &RaceState<SourceHeaderId, TargetHeaderId, MessageNonce, Proof>,
 	strategy: &mut Strategy,
diff --git a/bridges/relays/messages-relay/src/message_race_strategy.rs b/bridges/relays/messages-relay/src/message_race_strategy.rs
index a22331fe07d1..4aabf6c200af 100644
--- a/bridges/relays/messages-relay/src/message_race_strategy.rs
+++ b/bridges/relays/messages-relay/src/message_race_strategy.rs
@@ -68,6 +68,17 @@ where
 		self.source_queue.is_empty()
 	}
 
+	fn best_at_source(&self) -> Nonce {
+		self.source_queue
+			.back()
+			.map(|(_, nonce)| *nonce)
+			.unwrap_or_else(Zero::zero)
+	}
+
+	fn best_at_target(&self) -> Nonce {
+		self.target_nonce
+	}
+
 	fn source_nonces_updated(
 		&mut self,
 		at_block: HeaderId<SourceHeaderHash, SourceHeaderNumber>,