Move transactions protocol to its own crate (#12264)

* Move transaction protocol to its own crate

* Update Cargo.lock

* Fix binaries

* Update client/network/transactions/src/lib.rs

Co-authored-by: Dmitry Markin <dmitry@markin.tech>

* Update client/service/src/builder.rs

Co-authored-by: Bastian Köcher <info@kchr.de>

* Apply review comments

* Revert one change and apply cargo-fmt

* Remove Transaction from Message

* Add array-bytes

* trigger CI

* Add comment about codec index

Co-authored-by: Dmitry Markin <dmitry@markin.tech>
Co-authored-by: Bastian Köcher <info@kchr.de>

substrate/client/network/src/service.rs

@@ -29,9 +29,8 @@
 
 use crate::{
 	behaviour::{self, Behaviour, BehaviourOut},
-	config::{Params, TransportConfig},
+	config::Params,
 	discovery::DiscoveryConfig,
-	error::Error,
 	network_state::{
 		NetworkState, NotConnectedPeer as NetworkStateNotConnectedPeer, Peer as NetworkStatePeer,
 	},
@@ -39,7 +38,7 @@ use crate::{
 		self, message::generic::Roles, NotificationsSink, NotifsHandlerError, PeerInfo, Protocol,
 		Ready,
 	},
-	transactions, transport, ExHashT, ReputationChange,
+	transport, ReputationChange,
 };
 
 use codec::Encode as _;
@@ -60,7 +59,8 @@ use metrics::{Histogram, HistogramVec, MetricSources, Metrics};
 use parking_lot::Mutex;
 use sc_consensus::{BlockImportError, BlockImportStatus, ImportQueue, Link};
 use sc_network_common::{
-	config::MultiaddrWithPeerId,
+	config::{MultiaddrWithPeerId, TransportConfig},
+	error::Error,
 	protocol::{
 		event::{DhtEvent, Event},
 		ProtocolName,
@@ -73,6 +73,7 @@ use sc_network_common::{
 		NotificationSenderReady as NotificationSenderReadyT, Signature, SigningError,
 	},
 	sync::{SyncState, SyncStatus},
+	ExHashT,
 };
 use sc_peerset::PeersetHandle;
 use sc_utils::mpsc::{tracing_unbounded, TracingUnboundedReceiver, TracingUnboundedSender};
@@ -101,7 +102,7 @@ mod out_events;
 mod tests;
 
 pub use libp2p::identity::{error::DecodingError, Keypair, PublicKey};
-use sc_network_common::service::{NetworkBlock, NetworkRequest, NetworkTransaction};
+use sc_network_common::service::{NetworkBlock, NetworkRequest};
 
 /// Substrate network service. Handles network IO and manages connectivity.
 pub struct NetworkService<B: BlockT + 'static, H: ExHashT> {
@@ -121,7 +122,7 @@ pub struct NetworkService<B: BlockT + 'static, H: ExHashT> {
 	/// nodes it should be connected to or not.
 	peerset: PeersetHandle,
 	/// Channel that sends messages to the actual worker.
-	to_worker: TracingUnboundedSender<ServiceToWorkerMsg<B, H>>,
+	to_worker: TracingUnboundedSender<ServiceToWorkerMsg<B>>,
 	/// For each peer and protocol combination, an object that allows sending notifications to
 	/// that peer. Updated by the [`NetworkWorker`].
 	peers_notifications_sinks: Arc<Mutex<HashMap<(PeerId, ProtocolName), NotificationsSink>>>,
@@ -144,7 +145,7 @@ where
 	/// Returns a `NetworkWorker` that implements `Future` and must be regularly polled in order
 	/// for the network processing to advance. From it, you can extract a `NetworkService` using
 	/// `worker.service()`. The `NetworkService` can be shared through the codebase.
-	pub fn new(mut params: Params<B, H, Client>) -> Result<Self, Error> {
+	pub fn new(mut params: Params<B, Client>) -> Result<Self, Error> {
 		// Private and public keys configuration.
 		let local_identity = params.network_config.node_key.clone().into_keypair()?;
 		let local_public = local_identity.public();
@@ -215,21 +216,6 @@ where
 			fs::create_dir_all(path)?;
 		}
 
-		let transactions_handler_proto = transactions::TransactionsHandlerPrototype::new(
-			params.protocol_id.clone(),
-			params
-				.chain
-				.hash(0u32.into())
-				.ok()
-				.flatten()
-				.expect("Genesis block exists; qed"),
-			params.fork_id.clone(),
-		);
-		params
-			.network_config
-			.extra_sets
-			.insert(0, transactions_handler_proto.set_config());
-
 		info!(
 			target: "sub-libp2p",
 			"🏷  Local node identity is: {}",
@@ -244,11 +230,8 @@ where
 			params.protocol_id.clone(),
 			&params.fork_id,
 			&params.network_config,
-			iter::once(Vec::new())
-				.chain(
-					(0..params.network_config.extra_sets.len() - 1)
-						.map(|_| default_notif_handshake_message.clone()),
-				)
+			(0..params.network_config.extra_sets.len())
+				.map(|_| default_notif_handshake_message.clone())
 				.collect(),
 			params.metrics_registry.as_ref(),
 			params.chain_sync,
@@ -465,13 +448,6 @@ where
 			_marker: PhantomData,
 		});
 
-		let (tx_handler, tx_handler_controller) = transactions_handler_proto.build(
-			service.clone(),
-			params.transaction_pool,
-			params.metrics_registry.as_ref(),
-		)?;
-		(params.transactions_handler_executor)(tx_handler.run().boxed());
-
 		Ok(NetworkWorker {
 			external_addresses,
 			num_connected,
@@ -482,9 +458,9 @@ where
 			from_service,
 			event_streams: out_events::OutChannels::new(params.metrics_registry.as_ref())?,
 			peers_notifications_sinks,
-			tx_handler_controller,
 			metrics,
 			boot_node_ids,
+			_marker: Default::default(),
 		})
 	}
 
@@ -1149,20 +1125,6 @@ where
 	}
 }
 
-impl<B, H> NetworkTransaction<H> for NetworkService<B, H>
-where
-	B: BlockT + 'static,
-	H: ExHashT,
-{
-	fn trigger_repropagate(&self) {
-		let _ = self.to_worker.unbounded_send(ServiceToWorkerMsg::PropagateTransactions);
-	}
-
-	fn propagate_transaction(&self, hash: H) {
-		let _ = self.to_worker.unbounded_send(ServiceToWorkerMsg::PropagateTransaction(hash));
-	}
-}
-
 impl<B, H> NetworkBlock<B::Hash, NumberFor<B>> for NetworkService<B, H>
 where
 	B: BlockT + 'static,
@@ -1249,9 +1211,7 @@ impl<'a> NotificationSenderReadyT for NotificationSenderReady<'a> {
 /// Messages sent from the `NetworkService` to the `NetworkWorker`.
 ///
 /// Each entry corresponds to a method of `NetworkService`.
-enum ServiceToWorkerMsg<B: BlockT, H: ExHashT> {
-	PropagateTransaction(H),
-	PropagateTransactions,
+enum ServiceToWorkerMsg<B: BlockT> {
 	RequestJustification(B::Hash, NumberFor<B>),
 	ClearJustificationRequests,
 	AnnounceBlock(B::Hash, Option<Vec<u8>>),
@@ -1309,7 +1269,7 @@ where
 	/// The import queue that was passed at initialization.
 	import_queue: Box<dyn ImportQueue<B>>,
 	/// Messages from the [`NetworkService`] that must be processed.
-	from_service: TracingUnboundedReceiver<ServiceToWorkerMsg<B, H>>,
+	from_service: TracingUnboundedReceiver<ServiceToWorkerMsg<B>>,
 	/// Senders for events that happen on the network.
 	event_streams: out_events::OutChannels,
 	/// Prometheus network metrics.
@@ -1319,8 +1279,9 @@ where
 	/// For each peer and protocol combination, an object that allows sending notifications to
 	/// that peer. Shared with the [`NetworkService`].
 	peers_notifications_sinks: Arc<Mutex<HashMap<(PeerId, ProtocolName), NotificationsSink>>>,
-	/// Controller for the handler of incoming and outgoing transactions.
-	tx_handler_controller: transactions::TransactionsHandlerController<H>,
+	/// Marker to pin the `H` generic. Serves no purpose except to not break backwards
+	/// compatibility.
+	_marker: PhantomData<H>,
 }
 
 impl<B, H, Client> Future for NetworkWorker<B, H, Client>
@@ -1376,10 +1337,6 @@ where
 					.behaviour_mut()
 					.user_protocol_mut()
 					.clear_justification_requests(),
-				ServiceToWorkerMsg::PropagateTransaction(hash) =>
-					this.tx_handler_controller.propagate_transaction(hash),
-				ServiceToWorkerMsg::PropagateTransactions =>
-					this.tx_handler_controller.propagate_transactions(),
 				ServiceToWorkerMsg::GetValue(key) =>
 					this.network_service.behaviour_mut().get_value(key),
 				ServiceToWorkerMsg::PutValue(key, value) =>
@@ -1922,8 +1879,6 @@ where
 				SyncState::Downloading => true,
 			};
 
-		this.tx_handler_controller.set_gossip_enabled(!is_major_syncing);
-
 		this.is_major_syncing.store(is_major_syncing, Ordering::Relaxed);
 
 		if let Some(metrics) = this.metrics.as_ref() {