Extract syncing protocol from sc-network (paritytech#12828)

* Move import queue out of `sc-network`

Add supplementary asynchronous API for the import queue which means
it can be run as an independent task and communicated with through
the `ImportQueueService`.

This commit removes removes block and justification imports from
`sc-network` and provides `ChainSync` with a handle to import queue so
it can import blocks and justifications. Polling of the import queue is
moved complete out of `sc-network` and `sc_consensus::Link` is
implemented for `ChainSyncInterfaceHandled` so the import queue
can still influence the syncing process.

* Move stuff to SyncingEngine

* Move `ChainSync` instanation to `SyncingEngine`

Some of the tests have to be rewritten

* Move peer hashmap to `SyncingEngine`

* Let `SyncingEngine` to implement `ChainSyncInterface`

* Introduce `SyncStatusProvider`

* Move `sync_peer_(connected|disconnected)` to `SyncingEngine`

* Implement `SyncEventStream`

Remove `SyncConnected`/`SyncDisconnected` events from
`NetworkEvenStream` and provide those events through
`ChainSyncInterface` instead.

Modify BEEFY/GRANDPA/transactions protocol and `NetworkGossip` to take
`SyncEventStream` object which they listen to for incoming sync peer
events.

* Introduce `ChainSyncInterface`

This interface provides a set of miscellaneous functions that other
subsystems can use to query, for example, the syncing status.

* Move event stream polling to `SyncingEngine`

Subscribe to `NetworkStreamEvent` and poll the incoming notifications
and substream events from `SyncingEngine`.

The code needs refactoring.

* Make `SyncingEngine` into an asynchronous runner

This commits removes the last hard dependency of syncing from
`sc-network` meaning the protocol now lives completely outside of
`sc-network`, ignoring the hardcoded peerset entry which will be
addressed in the future.

Code needs a lot of refactoring.

* Fix warnings

* Code refactoring

* Use `SyncingService` for BEEFY

* Use `SyncingService` for GRANDPA

* Remove call delegation from `NetworkService`

* Remove `ChainSyncService`

* Remove `ChainSync` service tests

They were written for the sole purpose of verifying that `NetworWorker`
continues to function while the calls are being dispatched to
`ChainSync`.

* Refactor code

* Refactor code

* Update client/finality-grandpa/src/communication/tests.rs

Co-authored-by: Anton <anton.kalyaev@gmail.com>

* Fix warnings

* Apply review comments

* Fix docs

* Fix test

* cargo-fmt

* Update client/network/sync/src/engine.rs

Co-authored-by: Anton <anton.kalyaev@gmail.com>

* Update client/network/sync/src/engine.rs

Co-authored-by: Anton <anton.kalyaev@gmail.com>

* Add missing docs

* Refactor code

---------

Co-authored-by: Anton <anton.kalyaev@gmail.com>

bin/node-template/node/src/service.rs

@@ -192,7 +192,7 @@ pub fn new_full(mut config: Configuration) -> Result<TaskManager, ServiceError>
 		Vec::default(),
 	));
 
-	let (network, system_rpc_tx, tx_handler_controller, network_starter) =
+	let (network, system_rpc_tx, tx_handler_controller, network_starter, sync_service) =
 		sc_service::build_network(sc_service::BuildNetworkParams {
 			config: &config,
 			client: client.clone(),
@@ -240,6 +240,7 @@ pub fn new_full(mut config: Configuration) -> Result<TaskManager, ServiceError>
 		backend,
 		system_rpc_tx,
 		tx_handler_controller,
+		sync_service: sync_service.clone(),
 		config,
 		telemetry: telemetry.as_mut(),
 	})?;
@@ -276,8 +277,8 @@ pub fn new_full(mut config: Configuration) -> Result<TaskManager, ServiceError>
 				force_authoring,
 				backoff_authoring_blocks,
 				keystore: keystore_container.sync_keystore(),
-				sync_oracle: network.clone(),
-				justification_sync_link: network.clone(),
+				sync_oracle: sync_service.clone(),
+				justification_sync_link: sync_service.clone(),
 				block_proposal_slot_portion: SlotProportion::new(2f32 / 3f32),
 				max_block_proposal_slot_portion: None,
 				telemetry: telemetry.as_ref().map(|x| x.handle()),
@@ -320,6 +321,7 @@ pub fn new_full(mut config: Configuration) -> Result<TaskManager, ServiceError>
 			config: grandpa_config,
 			link: grandpa_link,
 			network,
+			sync: Arc::new(sync_service),
 			voting_rule: sc_consensus_grandpa::VotingRulesBuilder::default().build(),
 			prometheus_registry,
 			shared_voter_state: SharedVoterState::empty(),

bin/node/cli/Cargo.toml

@@ -68,6 +68,7 @@ sc-transaction-pool = { version = "4.0.0-dev", path = "../../../client/transacti
 sc-transaction-pool-api = { version = "4.0.0-dev", path = "../../../client/transaction-pool/api" }
 sc-network = { version = "0.10.0-dev", path = "../../../client/network" }
 sc-network-common = { version = "0.10.0-dev", path = "../../../client/network/common" }
+sc-network-sync = { version = "0.10.0-dev", path = "../../../client/network/sync" }
 sc-consensus-slots = { version = "0.10.0-dev", path = "../../../client/consensus/slots" }
 sc-consensus-babe = { version = "0.10.0-dev", path = "../../../client/consensus/babe" }
 grandpa = { version = "0.10.0-dev", package = "sc-consensus-grandpa", path = "../../../client/consensus/grandpa" }

bin/node/cli/src/chain_spec.rs

@@ -479,12 +479,13 @@ pub(crate) mod tests {
 		sp_tracing::try_init_simple();
 
 		sc_service_test::connectivity(integration_test_config_with_two_authorities(), |config| {
-			let NewFullBase { task_manager, client, network, transaction_pool, .. } =
+			let NewFullBase { task_manager, client, network, sync, transaction_pool, .. } =
 				new_full_base(config, false, |_, _| ())?;
 			Ok(sc_service_test::TestNetComponents::new(
 				task_manager,
 				client,
 				network,
+				sync,
 				transaction_pool,
 			))
 		});

bin/node/cli/src/service.rs

@@ -35,6 +35,7 @@ use sc_network::NetworkService;
 use sc_network_common::{
 	protocol::event::Event, service::NetworkEventStream, sync::warp::WarpSyncParams,
 };
+use sc_network_sync::SyncingService;
 use sc_service::{config::Configuration, error::Error as ServiceError, RpcHandlers, TaskManager};
 use sc_telemetry::{Telemetry, TelemetryWorker};
 use sp_api::ProvideRuntimeApi;
@@ -303,6 +304,8 @@ pub struct NewFullBase {
 	pub client: Arc<FullClient>,
 	/// The networking service of the node.
 	pub network: Arc<NetworkService<Block, <Block as BlockT>::Hash>>,
+	/// The syncing service of the node.
+	pub sync: Arc<SyncingService<Block>>,
 	/// The transaction pool of the node.
 	pub transaction_pool: Arc<TransactionPool>,
 	/// The rpc handlers of the node.
@@ -353,7 +356,7 @@ pub fn new_full_base(
 		Vec::default(),
 	));
 
-	let (network, system_rpc_tx, tx_handler_controller, network_starter) =
+	let (network, system_rpc_tx, tx_handler_controller, network_starter, sync_service) =
 		sc_service::build_network(sc_service::BuildNetworkParams {
 			config: &config,
 			client: client.clone(),
@@ -392,6 +395,7 @@ pub fn new_full_base(
 		task_manager: &mut task_manager,
 		system_rpc_tx,
 		tx_handler_controller,
+		sync_service: sync_service.clone(),
 		telemetry: telemetry.as_mut(),
 	})?;
 
@@ -434,8 +438,8 @@ pub fn new_full_base(
 			select_chain,
 			env: proposer,
 			block_import,
-			sync_oracle: network.clone(),
-			justification_sync_link: network.clone(),
+			sync_oracle: sync_service.clone(),
+			justification_sync_link: sync_service.clone(),
 			create_inherent_data_providers: move |parent, ()| {
 				let client_clone = client_clone.clone();
 				async move {
@@ -531,6 +535,7 @@ pub fn new_full_base(
 			config,
 			link: grandpa_link,
 			network: network.clone(),
+			sync: Arc::new(sync_service.clone()),
 			telemetry: telemetry.as_ref().map(|x| x.handle()),
 			voting_rule: grandpa::VotingRulesBuilder::default().build(),
 			prometheus_registry,
@@ -547,7 +552,14 @@ pub fn new_full_base(
 	}
 
 	network_starter.start_network();
-	Ok(NewFullBase { task_manager, client, network, transaction_pool, rpc_handlers })
+	Ok(NewFullBase {
+		task_manager,
+		client,
+		network,
+		sync: sync_service,
+		transaction_pool,
+		rpc_handlers,
+	})
 }
 
 /// Builds a new service for a full client.
@@ -627,7 +639,7 @@ mod tests {
 			chain_spec,
 			|config| {
 				let mut setup_handles = None;
-				let NewFullBase { task_manager, client, network, transaction_pool, .. } =
+				let NewFullBase { task_manager, client, network, sync, transaction_pool, .. } =
 					new_full_base(
 						config,
 						false,
@@ -641,6 +653,7 @@ mod tests {
 					task_manager,
 					client,
 					network,
+					sync,
 					transaction_pool,
 				);
 				Ok((node, setup_handles.unwrap()))
@@ -807,12 +820,13 @@ mod tests {
 		sc_service_test::consensus(
 			crate::chain_spec::tests::integration_test_config_with_two_authorities(),
 			|config| {
-				let NewFullBase { task_manager, client, network, transaction_pool, .. } =
+				let NewFullBase { task_manager, client, network, sync, transaction_pool, .. } =
 					new_full_base(config, false, |_, _| ())?;
 				Ok(sc_service_test::TestNetComponents::new(
 					task_manager,
 					client,
 					network,
+					sync,
 					transaction_pool,
 				))
 			},

client/cli/src/arg_enums.rs

@@ -251,15 +251,19 @@ pub enum SyncMode {
 	Warp,
 }
 
-impl Into<sc_network::config::SyncMode> for SyncMode {
-	fn into(self) -> sc_network::config::SyncMode {
+impl Into<sc_network_common::config::SyncMode> for SyncMode {
+	fn into(self) -> sc_network_common::config::SyncMode {
 		match self {
-			SyncMode::Full => sc_network::config::SyncMode::Full,
-			SyncMode::Fast =>
-				sc_network::config::SyncMode::Fast { skip_proofs: false, storage_chain_mode: false },
-			SyncMode::FastUnsafe =>
-				sc_network::config::SyncMode::Fast { skip_proofs: true, storage_chain_mode: false },
-			SyncMode::Warp => sc_network::config::SyncMode::Warp,
+			SyncMode::Full => sc_network_common::config::SyncMode::Full,
+			SyncMode::Fast => sc_network_common::config::SyncMode::Fast {
+				skip_proofs: false,
+				storage_chain_mode: false,
+			},
+			SyncMode::FastUnsafe => sc_network_common::config::SyncMode::Fast {
+				skip_proofs: true,
+				storage_chain_mode: false,
+			},
+			SyncMode::Warp => sc_network_common::config::SyncMode::Warp,
 		}
 	}
 }

client/cli/src/params/network_params.rs

@@ -18,11 +18,8 @@
 
 use crate::{arg_enums::SyncMode, params::node_key_params::NodeKeyParams};
 use clap::Args;
-use sc_network::{
-	config::{NetworkConfiguration, NodeKeyConfig},
-	multiaddr::Protocol,
-};
-use sc_network_common::config::{NonReservedPeerMode, SetConfig, TransportConfig};
+use sc_network::{config::NetworkConfiguration, multiaddr::Protocol};
+use sc_network_common::config::{NodeKeyConfig, NonReservedPeerMode, SetConfig, TransportConfig};
 use sc_service::{
 	config::{Multiaddr, MultiaddrWithPeerId},
 	ChainSpec, ChainType,

client/cli/src/params/node_key_params.rs

@@ -17,7 +17,7 @@
 // along with this program. If not, see <https://www.gnu.org/licenses/>.
 
 use clap::Args;
-use sc_network::config::{identity::ed25519, NodeKeyConfig};
+use sc_network_common::config::{identity::ed25519, NodeKeyConfig};
 use sp_core::H256;
 use std::{path::PathBuf, str::FromStr};
 
@@ -92,7 +92,7 @@ impl NodeKeyParams {
 				let secret = if let Some(node_key) = self.node_key.as_ref() {
 					parse_ed25519_secret(node_key)?
 				} else {
-					sc_network::config::Secret::File(
+					sc_network_common::config::Secret::File(
 						self.node_key_file
 							.clone()
 							.unwrap_or_else(|| net_config_dir.join(NODE_KEY_ED25519_FILE)),
@@ -111,10 +111,10 @@ fn invalid_node_key(e: impl std::fmt::Display) -> error::Error {
 }
 
 /// Parse a Ed25519 secret key from a hex string into a `sc_network::Secret`.
-fn parse_ed25519_secret(hex: &str) -> error::Result<sc_network::config::Ed25519Secret> {
+fn parse_ed25519_secret(hex: &str) -> error::Result<sc_network_common::config::Ed25519Secret> {
 	H256::from_str(hex).map_err(invalid_node_key).and_then(|bytes| {
 		ed25519::SecretKey::from_bytes(bytes)
-			.map(sc_network::config::Secret::Input)
+			.map(sc_network_common::config::Secret::Input)
 			.map_err(invalid_node_key)
 	})
 }
@@ -123,7 +123,7 @@ fn parse_ed25519_secret(hex: &str) -> error::Result<sc_network::config::Ed25519S
 mod tests {
 	use super::*;
 	use clap::ValueEnum;
-	use sc_network::config::identity::{ed25519, Keypair};
+	use sc_network_common::config::identity::{ed25519, Keypair};
 	use std::fs;
 
 	#[test]
@@ -140,7 +140,7 @@ mod tests {
 					node_key_file: None,
 				};
 				params.node_key(net_config_dir).and_then(|c| match c {
-					NodeKeyConfig::Ed25519(sc_network::config::Secret::Input(ref ski))
+					NodeKeyConfig::Ed25519(sc_network_common::config::Secret::Input(ref ski))
 						if node_key_type == NodeKeyType::Ed25519 && &sk[..] == ski.as_ref() =>
 						Ok(()),
 					_ => Err(error::Error::Input("Unexpected node key config".into())),
@@ -200,7 +200,7 @@ mod tests {
 				let dir = PathBuf::from(net_config_dir.clone());
 				let typ = params.node_key_type;
 				params.node_key(net_config_dir).and_then(move |c| match c {
-					NodeKeyConfig::Ed25519(sc_network::config::Secret::File(ref f))
+					NodeKeyConfig::Ed25519(sc_network_common::config::Secret::File(ref f))
 						if typ == NodeKeyType::Ed25519 && f == &dir.join(NODE_KEY_ED25519_FILE) =>
 						Ok(()),
 					_ => Err(error::Error::Input("Unexpected node key config".into())),

client/consensus/aura/src/lib.rs

@@ -766,6 +766,11 @@ mod tests {
 		fn peers(&self) -> &Vec<AuraPeer> {
 			&self.peers
 		}
+
+		fn peers_mut(&mut self) -> &mut Vec<AuraPeer> {
+			&mut self.peers
+		}
+
 		fn mut_peers<F: FnOnce(&mut Vec<AuraPeer>)>(&mut self, closure: F) {
 			closure(&mut self.peers);
 		}

client/consensus/babe/src/tests.rs

@@ -349,6 +349,11 @@ impl TestNetFactory for BabeTestNet {
 		&self.peers
 	}
 
+	fn peers_mut(&mut self) -> &mut Vec<BabePeer> {
+		trace!(target: "babe", "Retrieving peers, mutable");
+		&mut self.peers
+	}
+
 	fn mut_peers<F: FnOnce(&mut Vec<BabePeer>)>(&mut self, closure: F) {
 		closure(&mut self.peers);
 	}

client/consensus/beefy/Cargo.toml

@@ -25,6 +25,7 @@ sc-keystore = { version = "4.0.0-dev", path = "../../keystore" }
 sc-network = { version = "0.10.0-dev", path = "../../network" }
 sc-network-common = { version = "0.10.0-dev", path = "../../network/common" }
 sc-network-gossip = { version = "0.10.0-dev", path = "../../network-gossip" }
+sc-network-sync = { version = "0.10.0-dev", path = "../../network/sync" }
 sc-utils = { version = "4.0.0-dev", path = "../../utils" }
 sp-api = { version = "4.0.0-dev", path = "../../../primitives/api" }
 sp-application-crypto = { version = "7.0.0", path = "../../../primitives/application-crypto" }

client/consensus/beefy/src/lib.rs

@@ -40,7 +40,7 @@ use sc_client_api::{Backend, BlockBackend, BlockchainEvents, FinalityNotificatio
 use sc_consensus::BlockImport;
 use sc_network::ProtocolName;
 use sc_network_common::service::NetworkRequest;
-use sc_network_gossip::{GossipEngine, Network as GossipNetwork};
+use sc_network_gossip::{GossipEngine, Network as GossipNetwork, Syncing as GossipSyncing};
 use sp_api::{HeaderT, NumberFor, ProvideRuntimeApi};
 use sp_blockchain::{
 	Backend as BlockchainBackend, Error as ClientError, HeaderBackend, Result as ClientResult,
@@ -172,9 +172,11 @@ where
 }
 
 /// BEEFY gadget network parameters.
-pub struct BeefyNetworkParams<B: Block, N> {
+pub struct BeefyNetworkParams<B: Block, N, S> {
 	/// Network implementing gossip, requests and sync-oracle.
 	pub network: Arc<N>,
+	/// Syncing service implementing a sync oracle and an event stream for peers.
+	pub sync: Arc<S>,
 	/// Chain specific BEEFY gossip protocol name. See
 	/// [`communication::beefy_protocol_name::gossip_protocol_name`].
 	pub gossip_protocol_name: ProtocolName,
@@ -186,7 +188,7 @@ pub struct BeefyNetworkParams<B: Block, N> {
 }
 
 /// BEEFY gadget initialization parameters.
-pub struct BeefyParams<B: Block, BE, C, N, P, R> {
+pub struct BeefyParams<B: Block, BE, C, N, P, R, S> {
 	/// BEEFY client
 	pub client: Arc<C>,
 	/// Client Backend
@@ -198,7 +200,7 @@ pub struct BeefyParams<B: Block, BE, C, N, P, R> {
 	/// Local key store
 	pub key_store: Option<SyncCryptoStorePtr>,
 	/// BEEFY voter network params
-	pub network_params: BeefyNetworkParams<B, N>,
+	pub network_params: BeefyNetworkParams<B, N, S>,
 	/// Minimal delta between blocks, BEEFY should vote for
 	pub min_block_delta: u32,
 	/// Prometheus metric registry
@@ -212,15 +214,17 @@ pub struct BeefyParams<B: Block, BE, C, N, P, R> {
 /// Start the BEEFY gadget.
 ///
 /// This is a thin shim around running and awaiting a BEEFY worker.
-pub async fn start_beefy_gadget<B, BE, C, N, P, R>(beefy_params: BeefyParams<B, BE, C, N, P, R>)
-where
+pub async fn start_beefy_gadget<B, BE, C, N, P, R, S>(
+	beefy_params: BeefyParams<B, BE, C, N, P, R, S>,
+) where
 	B: Block,
 	BE: Backend<B>,
 	C: Client<B, BE> + BlockBackend<B>,
 	P: PayloadProvider<B>,
 	R: ProvideRuntimeApi<B>,
 	R::Api: BeefyApi<B> + MmrApi<B, MmrRootHash, NumberFor<B>>,
-	N: GossipNetwork<B> + NetworkRequest + SyncOracle + Send + Sync + 'static,
+	N: GossipNetwork<B> + NetworkRequest + Send + Sync + 'static,
+	S: GossipSyncing<B> + SyncOracle + 'static,
 {
 	let BeefyParams {
 		client,
@@ -235,14 +239,20 @@ where
 		on_demand_justifications_handler,
 	} = beefy_params;
 
-	let BeefyNetworkParams { network, gossip_protocol_name, justifications_protocol_name, .. } =
-		network_params;
+	let BeefyNetworkParams {
+		network,
+		sync,
+		gossip_protocol_name,
+		justifications_protocol_name,
+		..
+	} = network_params;
 
 	let known_peers = Arc::new(Mutex::new(KnownPeers::new()));
 	let gossip_validator =
 		Arc::new(communication::gossip::GossipValidator::new(known_peers.clone()));
 	let mut gossip_engine = sc_network_gossip::GossipEngine::new(
 		network.clone(),
+		sync.clone(),
 		gossip_protocol_name,
 		gossip_validator.clone(),
 		None,
@@ -280,7 +290,7 @@ where
 		backend,
 		payload_provider,
 		runtime,
-		network,
+		sync,
 		key_store: key_store.into(),
 		gossip_engine,
 		gossip_validator,