remove on_exit from grandpa (#5098)

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

@@ -154,7 +154,6 @@ pub fn new_full(config: Configuration<GenesisConfig>)
 			link: grandpa_link,
 			network: service.network(),
 			inherent_data_providers: inherent_data_providers.clone(),
-			on_exit: service.on_exit(),
 			telemetry_on_connect: Some(service.telemetry_on_connect_stream()),
 			voting_rule: grandpa::VotingRulesBuilder::default().build(),
 			prometheus_registry: service.prometheus_registry()

substrate/bin/node/cli/src/service.rs

@@ -225,7 +225,6 @@ macro_rules! new_full {
 				link: grandpa_link,
 				network: service.network(),
 				inherent_data_providers: inherent_data_providers.clone(),
-				on_exit: service.on_exit(),
 				telemetry_on_connect: Some(service.telemetry_on_connect_stream()),
 				voting_rule: grandpa::VotingRulesBuilder::default().build(),
 				prometheus_registry: service.prometheus_registry(),

substrate/client/finality-grandpa/src/lib.rs

@@ -536,7 +536,7 @@ fn register_finality_tracker_inherent_data_provider<Block: BlockT, Client>(
 }
 
 /// Parameters used to run Grandpa.
-pub struct GrandpaParams<Block: BlockT, C, N, SC, VR, X> {
+pub struct GrandpaParams<Block: BlockT, C, N, SC, VR> {
 	/// Configuration for the GRANDPA service.
 	pub config: Config,
 	/// A link to the block import worker.
@@ -545,8 +545,6 @@ pub struct GrandpaParams<Block: BlockT, C, N, SC, VR, X> {
 	pub network: N,
 	/// The inherent data providers.
 	pub inherent_data_providers: InherentDataProviders,
-	/// Handle to a future that will resolve on exit.
-	pub on_exit: X,
 	/// If supplied, can be used to hook on telemetry connection established events.
 	pub telemetry_on_connect: Option<futures::channel::mpsc::UnboundedReceiver<()>>,
 	/// A voting rule used to potentially restrict target votes.
@@ -557,8 +555,8 @@ pub struct GrandpaParams<Block: BlockT, C, N, SC, VR, X> {
 
 /// Run a GRANDPA voter as a task. Provide configuration and a link to a
 /// block import worker that has already been instantiated with `block_import`.
-pub fn run_grandpa_voter<Block: BlockT, BE: 'static, C, N, SC, VR, X>(
+pub fn run_grandpa_voter<Block: BlockT, BE: 'static, C, N, SC, VR>(
-	grandpa_params: GrandpaParams<Block, C, N, SC, VR, X>,
+	grandpa_params: GrandpaParams<Block, C, N, SC, VR>,
 ) -> sp_blockchain::Result<impl Future<Output = ()> + Unpin + Send + 'static> where
 	Block::Hash: Ord,
 	BE: Backend<Block> + 'static,
@@ -567,7 +565,6 @@ pub fn run_grandpa_voter<Block: BlockT, BE: 'static, C, N, SC, VR, X>(
 	VR: VotingRule<Block, C> + Clone + 'static,
 	NumberFor<Block>: BlockNumberOps,
 	DigestFor<Block>: Encode,
-	X: futures::Future<Output=()> + Clone + Send + Unpin + 'static,
 	C: ClientForGrandpa<Block, BE> + 'static,
 {
 	let GrandpaParams {
@@ -575,7 +572,6 @@ pub fn run_grandpa_voter<Block: BlockT, BE: 'static, C, N, SC, VR, X>(
 		link,
 		network,
 		inherent_data_providers,
-		on_exit,
 		telemetry_on_connect,
 		voting_rule,
 		prometheus_registry,
@@ -647,7 +643,7 @@ pub fn run_grandpa_voter<Block: BlockT, BE: 'static, C, N, SC, VR, X>(
 	let telemetry_task = telemetry_task
 		.then(|_| future::pending::<()>());
 
-	Ok(future::select(future::select(voter_work, on_exit), telemetry_task).map(drop))
+	Ok(future::select(voter_work, telemetry_task).map(drop))
 }
 
 /// Future that powers the voter.

substrate/client/finality-grandpa/src/observer.rs

@@ -159,8 +159,8 @@ pub fn run_grandpa_observer<BE, Block: BlockT, Client, N, SC>(
 	config: Config,
 	link: LinkHalf<Block, Client, SC>,
 	network: N,
-	on_exit: impl futures::Future<Output=()> + Clone + Send + Unpin + 'static,
+) -> sp_blockchain::Result<impl Future<Output = ()> + Unpin + Send + 'static>
-) -> sp_blockchain::Result<impl Future<Output = ()> + Unpin + Send + 'static> where
+where
 	BE: Backend<Block> + Unpin + 'static,
 	N: NetworkT<Block> + Send + Clone + 'static,
 	SC: SelectChain<Block> + 'static,
@@ -194,7 +194,7 @@ pub fn run_grandpa_observer<BE, Block: BlockT, Client, N, SC>(
 			warn!("GRANDPA Observer failed: {:?}", e);
 		});
 
-	Ok(future::select(observer_work, on_exit).map(drop))
+	Ok(observer_work.map(drop))
 }
 
 /// Future that powers the observer.

substrate/client/finality-grandpa/src/tests.rs

@@ -190,17 +190,6 @@ impl TestNetFactory for GrandpaTestNet {
 	}
 }
 
-#[derive(Clone)]
-struct Exit;
-
-impl futures::Future for Exit {
-	type Output = ();
-
-	fn poll(self: Pin<&mut Self>, _: &mut task::Context) -> task::Poll<()> {
-		task::Poll::Pending
-	}
-}
-
 #[derive(Default, Clone)]
 pub(crate) struct TestApi {
 	genesis_authorities: AuthorityList,
@@ -444,7 +433,6 @@ fn run_to_completion_with<F>(
 			link: link,
 			network: net_service,
 			inherent_data_providers: InherentDataProviders::new(),
-			on_exit: Exit,
 			telemetry_on_connect: None,
 			voting_rule: (),
 			prometheus_registry: None,
@@ -576,7 +564,6 @@ fn finalize_3_voters_1_full_observer() {
 			link: link,
 			network: net_service,
 			inherent_data_providers: InherentDataProviders::new(),
-			on_exit: Exit,
 			telemetry_on_connect: None,
 			voting_rule: (),
 			prometheus_registry: None,
@@ -740,7 +727,6 @@ fn transition_3_voters_twice_1_full_observer() {
 			link: link,
 			network: net_service,
 			inherent_data_providers: InherentDataProviders::new(),
-			on_exit: Exit,
 			telemetry_on_connect: None,
 			voting_rule: (),
 			prometheus_registry: None,
@@ -1166,7 +1152,6 @@ fn voter_persists_its_votes() {
 							link,
 							network: this.net.lock().peers[0].network_service().clone(),
 							inherent_data_providers: InherentDataProviders::new(),
-							on_exit: Exit,
 							telemetry_on_connect: None,
 							voting_rule: VotingRulesBuilder::default().build(),
 							prometheus_registry: None,
@@ -1382,7 +1367,6 @@ fn finalize_3_voters_1_light_observer() {
 				},
 				link,
 				net.lock().peers[3].network_service().clone(),
-				Exit,
 			).unwrap()
 		);
 
@@ -1512,7 +1496,6 @@ fn voter_catches_up_to_latest_round_when_behind() {
 			link,
 			network: net.lock().peer(peer_id).network_service().clone(),
 			inherent_data_providers: InherentDataProviders::new(),
-			on_exit: Exit,
 			telemetry_on_connect: None,
 			voting_rule: (),
 			prometheus_registry: None,