Append SignedCommitment to block justifications (#177)

* Append SignedCommitment

* add BeefyParams

* add WorkerParams

* use warn

* versioned variant for SignedCommitment

Author: adoerr

client/beefy/src/lib.rs

@@ -26,7 +26,6 @@ use sc_network_gossip::{GossipEngine, Network as GossipNetwork};
 use sp_api::ProvideRuntimeApi;
 use sp_application_crypto::AppPublic;
 use sp_blockchain::HeaderBackend;
-use sp_consensus::SyncOracle as SyncOracleT;
 use sp_keystore::SyncCryptoStorePtr;
 use sp_runtime::traits::Block;
 
@@ -78,18 +77,34 @@ where
 	// empty
 }
 
+/// BEEFY gadget initialization parameters.
+pub struct BeefyParams<B, P, BE, C, N>
+where
+	B: Block,
+	P: sp_core::Pair,
+	P::Signature: Clone + Codec + Debug + PartialEq + TryFrom<Vec<u8>>,
+{
+	/// BEEFY client
+	pub client: Arc<C>,
+	/// Client Backend
+	pub backend: Arc<BE>,
+	/// Local key store
+	pub key_store: Option<SyncCryptoStorePtr>,
+	/// Gossip network
+	pub network: N,
+	/// BEEFY signed commitment sender
+	pub signed_commitment_sender: notification::BeefySignedCommitmentSender<B, P::Signature>,
+	/// Minimal delta between blocks, BEEFY should vote for
+	pub min_block_delta: u32,
+	/// Prometheus metric registry
+	pub prometheus_registry: Option<Registry>,
+}
+
 /// Start the BEEFY gadget.
 ///
 /// This is a thin shim around running and awaiting a BEEFY worker.
-pub async fn start_beefy_gadget<B, P, BE, C, N, SO>(
-	client: Arc<C>,
-	key_store: Option<SyncCryptoStorePtr>,
-	network: N,
-	signed_commitment_sender: notification::BeefySignedCommitmentSender<B, P::Signature>,
-	_sync_oracle: SO,
-	min_block_delta: u32,
-	prometheus_registry: Option<Registry>,
-) where
+pub async fn start_beefy_gadget<B, P, BE, C, N>(beefy_params: BeefyParams<B, P, BE, C, N>)
+where
 	B: Block,
 	P: sp_core::Pair,
 	P::Public: AppPublic + Codec,
@@ -98,8 +113,17 @@ pub async fn start_beefy_gadget<B, P, BE, C, N, SO>(
 	C: Client<B, BE, P>,
 	C::Api: BeefyApi<B, P::Public>,
 	N: GossipNetwork<B> + Clone + Send + 'static,
-	SO: SyncOracleT + Send + 'static,
 {
+	let BeefyParams {
+		client,
+		backend,
+		key_store,
+		network,
+		signed_commitment_sender,
+		min_block_delta,
+		prometheus_registry,
+	} = beefy_params;
+
 	let gossip_validator = Arc::new(gossip::BeefyGossipValidator::new());
 	let gossip_engine = GossipEngine::new(network, BEEFY_PROTOCOL_NAME, gossip_validator.clone(), None);
 
@@ -117,15 +141,18 @@ pub async fn start_beefy_gadget<B, P, BE, C, N, SO>(
 			}
 		});
 
-	let worker = worker::BeefyWorker::<_, _, BE, P>::new(
-		client.clone(),
+	let worker_params = worker::WorkerParams {
+		client,
+		backend,
 		key_store,
 		signed_commitment_sender,
 		gossip_engine,
 		gossip_validator,
 		min_block_delta,
 		metrics,
-	);
+	};
+
+	let worker = worker::BeefyWorker::<_, _, _, _>::new(worker_params);
 
 	worker.run().await
 }

client/beefy/src/worker.rs

@@ -42,8 +42,8 @@ use sp_runtime::{
 };
 
 use beefy_primitives::{
-	BeefyApi, Commitment, ConsensusLog, MmrRootHash, SignedCommitment, ValidatorSet, VoteMessage, BEEFY_ENGINE_ID,
-	GENESIS_AUTHORITY_SET_ID, KEY_TYPE,
+	BeefyApi, Commitment, ConsensusLog, MmrRootHash, SignedCommitment, ValidatorSet, VersionedCommitment, VoteMessage,
+	BEEFY_ENGINE_ID, GENESIS_AUTHORITY_SET_ID, KEY_TYPE,
 };
 
 use crate::{
@@ -54,6 +54,22 @@ use crate::{
 	notification, round, Client,
 };
 
+pub(crate) struct WorkerParams<B, P, BE, C>
+where
+	B: Block,
+	P: sp_core::Pair,
+	P::Signature: Clone + Codec + Debug + PartialEq + TryFrom<Vec<u8>>,
+{
+	pub client: Arc<C>,
+	pub backend: Arc<BE>,
+	pub key_store: Option<SyncCryptoStorePtr>,
+	pub signed_commitment_sender: notification::BeefySignedCommitmentSender<B, P::Signature>,
+	pub gossip_engine: GossipEngine<B>,
+	pub gossip_validator: Arc<BeefyGossipValidator<B, P>>,
+	pub min_block_delta: u32,
+	pub metrics: Option<Metrics>,
+}
+
 /// A BEEFY worker plays the BEEFY protocol
 pub(crate) struct BeefyWorker<B, C, BE, P>
 where
@@ -65,6 +81,7 @@ where
 	C: Client<B, BE, P>,
 {
 	client: Arc<C>,
+	backend: Arc<BE>,
 	key_store: Option<SyncCryptoStorePtr>,
 	signed_commitment_sender: notification::BeefySignedCommitmentSender<B, P::Signature>,
 	gossip_engine: Arc<Mutex<GossipEngine<B>>>,
@@ -101,17 +118,21 @@ where
 	/// BEEFY pallet has been deployed on-chain.
 	///
 	/// The BEEFY pallet is needed in order to keep track of the BEEFY authority set.
-	pub(crate) fn new(
-		client: Arc<C>,
-		key_store: Option<SyncCryptoStorePtr>,
-		signed_commitment_sender: notification::BeefySignedCommitmentSender<B, P::Signature>,
-		gossip_engine: GossipEngine<B>,
-		gossip_validator: Arc<BeefyGossipValidator<B, P>>,
-		min_block_delta: u32,
-		metrics: Option<Metrics>,
-	) -> Self {
+	pub(crate) fn new(worker_params: WorkerParams<B, P, BE, C>) -> Self {
+		let WorkerParams {
+			client,
+			backend,
+			key_store,
+			signed_commitment_sender,
+			gossip_engine,
+			gossip_validator,
+			min_block_delta,
+			metrics,
+		} = worker_params;
+
 		BeefyWorker {
 			client: client.clone(),
+			backend,
 			key_store,
 			signed_commitment_sender,
 			gossip_engine: Arc::new(Mutex::new(gossip_engine)),
@@ -313,6 +334,22 @@ where
 
 				debug!(target: "beefy", "🥩 Round #{} concluded, committed: {:?}.", round.1, signed_commitment);
 
+				if self
+					.backend
+					.append_justification(
+						BlockId::Number(round.1),
+						(
+							BEEFY_ENGINE_ID,
+							VersionedCommitment::V1(signed_commitment.clone()).encode(),
+						),
+					)
+					.is_err()
+				{
+					// this is a warning for now, because until the round lifecycle is improved, we will
+					// conclude certain rounds multiple times.
+					warn!(target: "beefy", "🥩 Failed to append justification: {:?}", signed_commitment);
+				}
+
 				self.signed_commitment_sender.notify(signed_commitment);
 				self.best_beefy_block = Some(round.1);
 

primitives/beefy/src/commitment.rs

@@ -95,13 +95,24 @@ impl<TBlockNumber, TPayload, TSignature> SignedCommitment<TBlockNumber, TPayload
 	}
 }
 
+/// A [SignedCommitment] with a version number. This variant will be appended
+/// to the block justifications for the block for which the signed commitment
+/// has been generated.
+#[derive(Clone, Debug, PartialEq, codec::Encode, codec::Decode)]
+pub enum VersionedCommitment<N, P, S> {
+	#[codec(index = 1)]
+	/// Current active version
+	V1(SignedCommitment<N, P, S>),
+}
+
 #[cfg(test)]
 mod tests {
 	use super::*;
 	use codec::Decode;
 
 	type TestCommitment = Commitment<u128, String>;
 	type TestSignedCommitment = SignedCommitment<u128, String, Vec<u8>>;
+	type TestVersionedCommitment = VersionedCommitment<u128, String, Vec<u8>>;
 
 	#[test]
 	fn commitment_encode_decode() {
@@ -195,4 +206,29 @@ mod tests {
 		assert!(c < d);
 		assert!(b < d);
 	}
+
+	#[test]
+	fn versioned_commitment_encode_decode() {
+		let commitment: TestCommitment = Commitment {
+			payload: "Hello World!".into(),
+			block_number: 5,
+			validator_set_id: 0,
+		};
+
+		let signed = SignedCommitment {
+			commitment,
+			signatures: vec![None, None, Some(vec![1, 2, 3, 4]), Some(vec![5, 6, 7, 8])],
+		};
+
+		let versioned = TestVersionedCommitment::V1(signed.clone());
+
+		let encoded = codec::Encode::encode(&versioned);
+
+		assert_eq!(1, encoded[0]);
+		assert_eq!(encoded[1..], codec::Encode::encode(&signed));
+
+		let decoded = TestVersionedCommitment::decode(&mut &*encoded);
+
+		assert_eq!(decoded, Ok(versioned));
+	}
 }

primitives/beefy/src/lib.rs

@@ -35,7 +35,7 @@
 mod commitment;
 pub mod witness;
 
-pub use commitment::{Commitment, SignedCommitment};
+pub use commitment::{Commitment, SignedCommitment, VersionedCommitment};
 
 use codec::{Codec, Decode, Encode};
 use sp_core::H256;