Introduce PerPeerSet utility that allows to segrate based on PeerSet (#2420)

* Introduce PerPeerSet utility that allows to segrate based on PeerSet

* Remove `repr(usize)` from PeerSet

polkadot/node/network/bridge/src/validator_discovery.rs

@@ -23,13 +23,12 @@ use std::sync::Arc;
 
 use async_trait::async_trait;
 use futures::channel::mpsc;
-use strum::IntoEnumIterator as _;
 
 use sc_network::multiaddr::{Multiaddr, Protocol};
 use sc_authority_discovery::Service as AuthorityDiscoveryService;
 use polkadot_node_network_protocol::PeerId;
 use polkadot_primitives::v1::{AuthorityDiscoveryId, Block, Hash};
-use polkadot_node_network_protocol::peer_set::PeerSet;
+use polkadot_node_network_protocol::peer_set::{PeerSet, PerPeerSet};
 
 const LOG_TARGET: &str = "validator_discovery";
 
@@ -140,9 +139,9 @@ fn peer_id_from_multiaddr(addr: &Multiaddr) -> Option<PeerId> {
 	})
 }
 
+
 pub(super) struct Service<N, AD> {
-	// indexed by PeerSet as usize
+	state: PerPeerSet<StatePerPeerSet>,
-	state: Vec<StatePerPeerSet>,
 	// PhantomData used to make the struct generic instead of having generic methods
 	_phantom: PhantomData<(N, AD)>,
 }
@@ -162,15 +161,11 @@ struct StatePerPeerSet {
 impl<N: Network, AD: AuthorityDiscovery> Service<N, AD> {
 	pub fn new() -> Self {
 		Self {
-			state: PeerSet::iter().map(|_| Default::default()).collect(),
+			state: PerPeerSet::default(),
 			_phantom: PhantomData,
 		}
 	}
 
-	fn state_mut(&mut self, peer_set: PeerSet) -> &mut StatePerPeerSet {
-		&mut self.state[peer_set as usize]
-	}
-
 	/// Find connected validators using the given `validator_ids`.
 	///
 	/// Returns a [`HashMap`] that contains the found [`AuthorityDiscoveryId`]'s and their associated [`PeerId`]'s.
@@ -182,7 +177,7 @@ impl<N: Network, AD: AuthorityDiscovery> Service<N, AD> {
 		authority_discovery_service: &mut AD,
 	) -> HashMap<AuthorityDiscoveryId, PeerId> {
 		let mut result = HashMap::new();
-		let state = self.state_mut(peer_set);
+		let state = &mut self.state[peer_set];
 
 		for id in validator_ids {
 			// First check if we already cached the validator
@@ -238,7 +233,7 @@ impl<N: Network, AD: AuthorityDiscovery> Service<N, AD> {
 			&mut authority_discovery_service,
 		).await;
 
-		let state = self.state_mut(peer_set);
+		let state = &mut self.state[peer_set];
 		// Increment the counter of how many times the validators were requested.
 		validator_ids.iter().for_each(|id| *state.requested_validators.entry(id.clone()).or_default() += 1);
 
@@ -336,7 +331,7 @@ impl<N: Network, AD: AuthorityDiscovery> Service<N, AD> {
 		peer_set: PeerSet,
 		authority_discovery_service: &mut AD,
 	) {
-		let state = self.state_mut(peer_set);
+		let state = &mut self.state[peer_set];
 		// check if it's an authority we've been waiting for
 		let maybe_authority = authority_discovery_service.get_authority_id_by_peer_id(peer_id.clone()).await;
 		if let Some(authority) = maybe_authority {
@@ -352,8 +347,7 @@ impl<N: Network, AD: AuthorityDiscovery> Service<N, AD> {
 
 	/// Should be called when a peer disconnected.
 	pub fn on_peer_disconnected(&mut self, peer_id: &PeerId, peer_set: PeerSet) {
-		let state = self.state_mut(peer_set);
+		self.state[peer_set].connected_peers.remove(peer_id);
-		state.connected_peers.remove(peer_id);
 	}
 }
 
@@ -569,7 +563,7 @@ mod tests {
 			let reply = receiver.next().await.unwrap();
 			assert_eq!(reply.0, authority_ids[1]);
 			assert_eq!(reply.1, peer_ids[1]);
-			let state = service.state_mut(PeerSet::Validation);
+			let state = &service.state[PeerSet::Validation];
 			assert_eq!(state.non_revoked_discovery_requests.len(), 1);
 		});
 	}
@@ -613,7 +607,7 @@ mod tests {
 			).await;
 
 			let _ = receiver.next().await.unwrap();
-			let state = service.state_mut(PeerSet::Validation);
+			let state = &service.state[PeerSet::Validation];
 			assert_eq!(state.non_revoked_discovery_requests.len(), 1);
 			assert_eq!(ns.peers_set.len(), 2);
 
@@ -631,7 +625,7 @@ mod tests {
 			).await;
 
 			let _ = receiver.next().await.unwrap();
-			let state = service.state_mut(PeerSet::Validation);
+			let state = &service.state[PeerSet::Validation];
 			assert_eq!(state.non_revoked_discovery_requests.len(), 1);
 			assert_eq!(ns.peers_set.len(), 1);
 		});
@@ -667,7 +661,7 @@ mod tests {
 			).await;
 
 			assert_eq!((validator_id.clone(), validator_peer_id.clone()), receiver.next().await.unwrap());
-			let state = service.state_mut(PeerSet::Validation);
+			let state = &service.state[PeerSet::Validation];
 			assert!(
 				state.connected_peers
 					.get(&validator_peer_id)

polkadot/node/network/protocol/src/peer_set.rs

@@ -17,18 +17,17 @@
 //! All peersets and protocols used for parachains.
 
 use sc_network::config::{NonDefaultSetConfig, SetConfig};
-use std::borrow::Cow;
+use std::{borrow::Cow, ops::{Index, IndexMut}};
 use strum::{EnumIter, IntoEnumIterator};
 
 /// The peer-sets and thus the protocols which are used for the network.
 #[derive(Debug, Clone, Copy, PartialEq, Eq, Hash, EnumIter)]
-#[repr(usize)]
 pub enum PeerSet {
 	/// The validation peer-set is responsible for all messages related to candidate validation and
 	/// communication among validators.
-	Validation = 0,
+	Validation,
 	/// The collation peer-set is used for validator<>collator communication.
-	Collation = 1,
+	Collation,
 }
 
 impl PeerSet {
@@ -89,6 +88,32 @@ impl PeerSet {
 	}
 }
 
+/// A small and nifty collection that allows to store data pertaining to each peer set.
+#[derive(Debug, Default)]
+pub struct PerPeerSet<T> {
+	validation: T,
+	collation: T,
+}
+
+impl<T> Index<PeerSet> for PerPeerSet<T> {
+	type Output = T;
+	fn index(&self, index: PeerSet) -> &T {
+		match index {
+			PeerSet::Validation => &self.validation,
+			PeerSet::Collation => &self.collation,
+		}
+	}
+}
+
+impl<T> IndexMut<PeerSet> for PerPeerSet<T> {
+    fn index_mut(&mut self, index: PeerSet) -> &mut T {
+        match index {
+			PeerSet::Validation => &mut self.validation,
+			PeerSet::Collation => &mut self.collation,
+		}
+    }
+}
+
 /// Get `NonDefaultSetConfig`s for all available peer sets.
 ///
 /// Should be used during network configuration (added to [`NetworkConfiguration::extra_sets`])