Fixed client used in headers maintain (paritytech#487)

* fixed client used in headers maintain

* fmt

bridges/relays/substrate/src/headers_maintain.rs

@@ -44,13 +44,14 @@ use relay_substrate_client::{Chain, Client, Error as SubstrateError, Justificati
 use relay_utils::HeaderId;
 use sp_core::Bytes;
 use sp_runtime::{traits::Header as HeaderT, Justification};
-use std::{collections::VecDeque, task::Poll};
+use std::{collections::VecDeque, marker::PhantomData, task::Poll};
 
 /// Substrate-to-Substrate headers synchronization maintain procedure.
-pub struct SubstrateHeadersToSubstrateMaintain<P: SubstrateHeadersSyncPipeline, C: Chain> {
+pub struct SubstrateHeadersToSubstrateMaintain<P: SubstrateHeadersSyncPipeline, SourceChain, TargetChain: Chain> {
 	pipeline: P,
-	target_client: Client<C>,
+	target_client: Client<TargetChain>,
 	justifications: Arc<Mutex<Justifications<P>>>,
+	_marker: PhantomData<SourceChain>,
 }
 
 /// Future and already received justifications from the source chain.
@@ -62,26 +63,32 @@ struct Justifications<P: SubstrateHeadersSyncPipeline> {
 	queue: VecDeque<(HeaderIdOf<P>, Justification)>,
 }
 
-impl<P: SubstrateHeadersSyncPipeline, C: Chain> SubstrateHeadersToSubstrateMaintain<P, C> {
+impl<P: SubstrateHeadersSyncPipeline, SourceChain, TargetChain: Chain>
+	SubstrateHeadersToSubstrateMaintain<P, SourceChain, TargetChain>
+{
 	/// Create new maintain procedure.
-	pub fn new(pipeline: P, target_client: Client<C>, justifications: JustificationsSubscription) -> Self {
+	pub fn new(pipeline: P, target_client: Client<TargetChain>, justifications: JustificationsSubscription) -> Self {
 		SubstrateHeadersToSubstrateMaintain {
 			pipeline,
 			target_client,
 			justifications: Arc::new(Mutex::new(Justifications {
 				stream: justifications,
 				queue: VecDeque::new(),
 			})),
+			_marker: Default::default(),
 		}
 	}
 }
 
 #[async_trait]
-impl<P, C> SyncMaintain<P> for SubstrateHeadersToSubstrateMaintain<P, C>
+impl<P, SourceChain, TargetChain> SyncMaintain<P> for SubstrateHeadersToSubstrateMaintain<P, SourceChain, TargetChain>
 where
-	C: Chain,
-	P::Number: Decode + From<C::BlockNumber>,
-	P::Hash: Decode + From<C::Hash>,
+	SourceChain: Chain,
+	<SourceChain::Header as HeaderT>::Number: Into<P::Number>,
+	<SourceChain::Header as HeaderT>::Hash: Into<P::Hash>,
+	TargetChain: Chain,
+	P::Number: Decode,
+	P::Hash: Decode,
 	P: SubstrateHeadersSyncPipeline<Completion = Justification, Extra = ()>,
 {
 	async fn maintain(&self, sync: &mut HeadersSync<P>) {
@@ -122,7 +129,7 @@ where
 		// on every maintain call. So maintain rate directly affects finalization rate.
 		let justification_to_submit = poll_fn(|context| {
 			// read justifications from the stream and push to the queue
-			justifications.read_from_stream::<C::Header>(context);
+			justifications.read_from_stream::<SourceChain::Header>(context);
 
 			// remove all obsolete justifications from the queue
 			remove_obsolete::<P>(&mut justifications.queue, best_finalized);
@@ -166,11 +173,11 @@ where
 	P: SubstrateHeadersSyncPipeline<Completion = Justification, Extra = ()>,
 {
 	/// Read justifications from the subscription stream without blocking.
-	fn read_from_stream<'a, Header>(&mut self, context: &mut std::task::Context<'a>)
+	fn read_from_stream<'a, SourceHeader>(&mut self, context: &mut std::task::Context<'a>)
 	where
-		Header: HeaderT,
-		Header::Number: Into<P::Number>,
-		Header::Hash: Into<P::Hash>,
+		SourceHeader: HeaderT,
+		SourceHeader::Number: Into<P::Number>,
+		SourceHeader::Hash: Into<P::Hash>,
 	{
 		loop {
 			let maybe_next_justification = self.stream.next();
@@ -183,7 +190,7 @@ where
 			};
 
 			// decode justification target
-			let target = pallet_substrate_bridge::decode_justification_target::<Header>(&justification);
+			let target = pallet_substrate_bridge::decode_justification_target::<SourceHeader>(&justification);
 			let target = match target {
 				Ok((target_hash, target_number)) => HeaderId(target_number.into(), target_hash.into()),
 				Err(error) => {
@@ -266,18 +273,18 @@ where
 async fn best_finalized_header_id<P, C>(client: &Client<C>) -> Result<HeaderIdOf<P>, SubstrateError>
 where
 	P: SubstrateHeadersSyncPipeline,
-	P::Number: Decode + From<C::BlockNumber>,
-	P::Hash: Decode + From<C::Hash>,
+	P::Number: Decode,
+	P::Hash: Decode,
 	C: Chain,
 {
 	let call = P::FINALIZED_BLOCK_METHOD.into();
 	let data = Bytes(Vec::new());
 
 	let encoded_response = client.state_call(call, data, None).await?;
-	let decoded_response: (C::BlockNumber, C::Hash) =
+	let decoded_response: (P::Number, P::Hash) =
 		Decode::decode(&mut &encoded_response.0[..]).map_err(SubstrateError::ResponseParseFailed)?;
 
-	let best_header_id = HeaderId(decoded_response.0.into(), decoded_response.1.into());
+	let best_header_id = HeaderId(decoded_response.0, decoded_response.1);
 	Ok(best_header_id)
 }
 

bridges/relays/substrate/src/headers_pipeline.rs

@@ -124,8 +124,11 @@ pub async fn run<SourceChain, TargetChain, P>(
 		}
 	};
 
-	let sync_maintain =
-		SubstrateHeadersToSubstrateMaintain::new(pipeline.clone(), source_client.clone(), source_justifications);
+	let sync_maintain = SubstrateHeadersToSubstrateMaintain::<_, SourceChain, _>::new(
+		pipeline.clone(),
+		target_client.clone(),
+		source_justifications,
+	);
 
 	headers_relay::sync_loop::run(
 		HeadersSource::new(source_client),