Rework BeefyAPI (#110)

client/beefy/src/lib.rs

@@ -111,12 +111,13 @@ pub async fn start_beefy_gadget<Block, Pair, Backend, Client, Network, SyncOracl
 	);
 
 	let at = BlockId::hash(client.info().best_hash);
-	let authorities = client
+	let validator_set = client
 		.runtime_api()
-		.authorities(&at)
+		.validator_set(&at)
 		.expect("Failed to get BEEFY authorities");
 
-	let local_id = match authorities
+	let local_id = match validator_set
+		.validators
 		.iter()
 		.find(|id| SyncCryptoStore::has_keys(&*key_store, &[(id.to_raw_vec(), KEY_TYPE)]))
 	{
@@ -136,7 +137,7 @@ pub async fn start_beefy_gadget<Block, Pair, Backend, Client, Network, SyncOracl
 	let worker = worker::BeefyWorker::<_, Pair::Public, Pair::Signature, _>::new(
 		local_id,
 		key_store,
-		authorities,
+		validator_set.validators,
 		client.finality_notification_stream(),
 		gossip_engine,
 		signed_commitment_sender,

frame/beefy/src/lib.rs

@@ -96,6 +96,14 @@ pub mod pallet {
 }
 
 impl<T: Config> Pallet<T> {
+	/// Return the current active BEEFY validator set.
+	pub fn validator_set() -> ValidatorSet<T::AuthorityId> {
+		ValidatorSet::<T::AuthorityId> {
+			validators: Self::authorities(),
+			id: Self::validator_set_id(),
+		}
+	}
+
 	fn change_authorities(new: Vec<T::AuthorityId>, queued: Vec<T::AuthorityId>) {
 		// As in GRANDPA, we trigger a validator set change only if the the validator
 		// set has actually changed.

frame/beefy/src/tests.rs

@@ -103,3 +103,39 @@ fn session_change_updates_next_authorities() {
 		assert_eq!(want[3], next_authorities[1]);
 	});
 }
+
+#[test]
+fn validator_set_at_genesis() {
+	let want = vec![mock_beefy_id(1), mock_beefy_id(2)];
+
+	new_test_ext(vec![1, 2, 3, 4]).execute_with(|| {
+		let vs = Beefy::validator_set();
+
+		assert_eq!(vs.id, 0u64);
+		assert_eq!(vs.validators[0], want[0]);
+		assert_eq!(vs.validators[1], want[1]);
+	});
+}
+
+#[test]
+fn validator_set_updates_work() {
+	let want = vec![mock_beefy_id(1), mock_beefy_id(2), mock_beefy_id(3), mock_beefy_id(4)];
+
+	new_test_ext(vec![1, 2, 3, 4]).execute_with(|| {
+		init_block(1);
+
+		let vs = Beefy::validator_set();
+
+		assert_eq!(vs.id, 0u64);
+		assert_eq!(want[0], vs.validators[0]);
+		assert_eq!(want[1], vs.validators[1]);
+
+		init_block(2);
+
+		let vs = Beefy::validator_set();
+
+		assert_eq!(vs.id, 1u64);
+		assert_eq!(want[2], vs.validators[0]);
+		assert_eq!(want[3], vs.validators[1]);
+	});
+}

primitives/beefy/src/lib.rs

@@ -70,7 +70,7 @@ pub const BEEFY_ENGINE_ID: sp_runtime::ConsensusEngineId = *b"BEEF";
 pub type ValidatorSetId = u64;
 
 /// A set of BEEFY authorities, a.k.a. validators.
-#[derive(Decode, Encode, Debug)]
+#[derive(Decode, Encode, Debug, PartialEq)]
 pub struct ValidatorSet<AuthorityId> {
 	/// Public keys of the validator set elements
 	pub validators: Vec<AuthorityId>,
@@ -101,7 +101,7 @@ pub enum ConsensusLog<AuthorityId: Codec> {
 sp_api::decl_runtime_apis! {
 	/// API necessary for BEEFY voters.
 	pub trait BeefyApi<AuthorityId: Codec> {
-		/// Return the current set of authorities.
-		fn authorities() -> Vec<AuthorityId>;
+		/// Return the current active BEEFY validator set
+		fn validator_set() -> ValidatorSet<AuthorityId>;
 	}
 }