use tokio reactor to execute jsonrpsee futures (#1061)

bridges/relays/bin-ethereum/src/rialto_client.rs

@@ -155,11 +155,12 @@ impl SubmitEthereumHeaders for SubstrateClient<Rialto> {
 		headers: Vec<QueuedEthereumHeader>,
 	) -> SubmittedHeaders<EthereumHeaderId, RpcError> {
 		let ids = headers.iter().map(|header| header.id()).collect();
+		let genesis_hash = *self.genesis_hash();
 		let submission_result = async {
-			self.submit_signed_extrinsic((*params.public().as_array_ref()).into(), |transaction_nonce| {
+			self.submit_signed_extrinsic((*params.public().as_array_ref()).into(), move |transaction_nonce| {
 				Bytes(
 					Rialto::sign_transaction(
-						*self.genesis_hash(),
+						genesis_hash,
 						&params,
 						transaction_nonce,
 						instance.build_signed_header_call(headers),
@@ -257,10 +258,11 @@ impl SubmitEthereumExchangeTransactionProof for SubstrateClient<Rialto> {
 		instance: Arc<dyn BridgeInstance>,
 		proof: rialto_runtime::exchange::EthereumTransactionInclusionProof,
 	) -> RpcResult<()> {
-		self.submit_signed_extrinsic((*params.public().as_array_ref()).into(), |transaction_nonce| {
+		let genesis_hash = *self.genesis_hash();
+		self.submit_signed_extrinsic((*params.public().as_array_ref()).into(), move |transaction_nonce| {
 			Bytes(
 				Rialto::sign_transaction(
-					*self.genesis_hash(),
+					genesis_hash,
 					&params,
 					transaction_nonce,
 					instance.build_currency_exchange_call(proof),

bridges/relays/bin-substrate/src/cli/send_message.rs

@@ -176,10 +176,11 @@ impl SendMessage {
 				fee,
 			})?;
 
+			let source_genesis_hash = *source_client.genesis_hash();
 			source_client
-				.submit_signed_extrinsic(source_sign.public().into(), |transaction_nonce| {
+				.submit_signed_extrinsic(source_sign.public().into(), move |transaction_nonce| {
 					let signed_source_call = Source::sign_transaction(
-						*source_client.genesis_hash(),
+						source_genesis_hash,
 						&source_sign,
 						transaction_nonce,
 						send_message_call,

bridges/relays/bin-substrate/src/finality_target.rs

@@ -80,10 +80,11 @@ where
 	}
 
 	async fn submit_finality_proof(&self, header: P::Header, proof: P::FinalityProof) -> Result<(), SubstrateError> {
+		let transactions_author = self.pipeline.transactions_author();
+		let pipeline = self.pipeline.clone();
 		self.client
-			.submit_signed_extrinsic(self.pipeline.transactions_author(), move |transaction_nonce| {
-				self.pipeline
-					.make_submit_finality_proof_transaction(transaction_nonce, header, proof)
+			.submit_signed_extrinsic(transactions_author, move |transaction_nonce| {
+				pipeline.make_submit_finality_proof_transaction(transaction_nonce, header, proof)
 			})
 			.await
 			.map(drop)

bridges/relays/bin-substrate/src/headers_initialize.rs

@@ -39,7 +39,9 @@ pub async fn initialize<SourceChain: Chain, TargetChain: Chain>(
 	source_client: Client<SourceChain>,
 	target_client: Client<TargetChain>,
 	target_transactions_signer: TargetChain::AccountId,
-	prepare_initialize_transaction: impl FnOnce(TargetChain::Index, InitializationData<SourceChain::Header>) -> Bytes,
+	prepare_initialize_transaction: impl FnOnce(TargetChain::Index, InitializationData<SourceChain::Header>) -> Bytes
+		+ Send
+		+ 'static,
 ) {
 	let result = do_initialize(
 		source_client,
@@ -72,7 +74,9 @@ async fn do_initialize<SourceChain: Chain, TargetChain: Chain>(
 	source_client: Client<SourceChain>,
 	target_client: Client<TargetChain>,
 	target_transactions_signer: TargetChain::AccountId,
-	prepare_initialize_transaction: impl FnOnce(TargetChain::Index, InitializationData<SourceChain::Header>) -> Bytes,
+	prepare_initialize_transaction: impl FnOnce(TargetChain::Index, InitializationData<SourceChain::Header>) -> Bytes
+		+ Send
+		+ 'static,
 ) -> Result<TargetChain::Hash, String> {
 	let initialization_data = prepare_initialization_data(source_client).await?;
 	log::info!(
@@ -102,7 +106,7 @@ async fn prepare_initialization_data<SourceChain: Chain>(
 	// But now there are problems with this approach - `CurrentSetId` may return invalid value. So here
 	// we're waiting for the next justification, read the authorities set and then try to figure out
 	// the set id with bruteforce.
-	let mut justifications = source_client
+	let justifications = source_client
 		.subscribe_justifications()
 		.await
 		.map_err(|err| format!("Failed to subscribe to {} justifications: {:?}", SourceChain::NAME, err))?;

bridges/relays/bin-substrate/src/messages_source.rs

@@ -233,10 +233,10 @@ where
 		generated_at_block: TargetHeaderIdOf<P>,
 		proof: P::MessagesReceivingProof,
 	) -> Result<(), SubstrateError> {
+		let lane = self.lane.clone();
 		self.client
 			.submit_signed_extrinsic(self.lane.source_transactions_author(), move |transaction_nonce| {
-				self.lane
-					.make_messages_receiving_proof_transaction(transaction_nonce, generated_at_block, proof)
+				lane.make_messages_receiving_proof_transaction(transaction_nonce, generated_at_block, proof)
 			})
 			.await?;
 		Ok(())

bridges/relays/bin-substrate/src/messages_target.rs

@@ -219,14 +219,11 @@ where
 		nonces: RangeInclusive<MessageNonce>,
 		proof: P::MessagesProof,
 	) -> Result<RangeInclusive<MessageNonce>, SubstrateError> {
+		let lane = self.lane.clone();
+		let nonces_clone = nonces.clone();
 		self.client
-			.submit_signed_extrinsic(self.lane.target_transactions_author(), |transaction_nonce| {
-				self.lane.make_messages_delivery_transaction(
-					transaction_nonce,
-					generated_at_header,
-					nonces.clone(),
-					proof,
-				)
+			.submit_signed_extrinsic(self.lane.target_transactions_author(), move |transaction_nonce| {
+				lane.make_messages_delivery_transaction(transaction_nonce, generated_at_header, nonces_clone, proof)
 			})
 			.await?;
 		Ok(nonces)

bridges/relays/client-ethereum/Cargo.toml

@@ -16,4 +16,5 @@ jsonrpsee-ws-client = "0.2"
 libsecp256k1 = { version = "0.3.4", default-features = false, features = ["hmac"] }
 log = "0.4.11"
 relay-utils = { path = "../utils" }
+tokio = "1.8"
 web3 = { git = "https://github.com/svyatonik/rust-web3.git", branch = "bump-deps" }

bridges/relays/client-ethereum/src/client.rs

@@ -23,7 +23,7 @@ use crate::{ConnectionParams, Error, Result};
 
 use jsonrpsee_ws_client::{WsClient as RpcClient, WsClientBuilder as RpcClientBuilder};
 use relay_utils::relay_loop::RECONNECT_DELAY;
-use std::sync::Arc;
+use std::{future::Future, sync::Arc};
 
 /// Number of headers missing from the Ethereum node for us to consider node not synced.
 const MAJOR_SYNC_BLOCKS: u64 = 5;
@@ -31,6 +31,7 @@ const MAJOR_SYNC_BLOCKS: u64 = 5;
 /// The client used to interact with an Ethereum node through RPC.
 #[derive(Clone)]
 pub struct Client {
+	tokio: Arc<tokio::runtime::Runtime>,
 	params: ConnectionParams,
 	client: Arc<RpcClient>,
 }
@@ -59,22 +60,23 @@ impl Client {
 	/// Try to connect to Ethereum node. Returns Ethereum RPC client if connection has been established
 	/// or error otherwise.
 	pub async fn try_connect(params: ConnectionParams) -> Result<Self> {
-		Ok(Self {
-			client: Self::build_client(&params).await?,
-			params,
-		})
+		let (tokio, client) = Self::build_client(&params).await?;
+		Ok(Self { tokio, client, params })
 	}
 
 	/// Build client to use in connection.
-	async fn build_client(params: &ConnectionParams) -> Result<Arc<RpcClient>> {
+	async fn build_client(params: &ConnectionParams) -> Result<(Arc<tokio::runtime::Runtime>, Arc<RpcClient>)> {
+		let tokio = tokio::runtime::Runtime::new()?;
 		let uri = format!("ws://{}:{}", params.host, params.port);
-		let client = RpcClientBuilder::default().build(&uri).await?;
-		Ok(Arc::new(client))
+		let client = tokio
+			.spawn(async move { RpcClientBuilder::default().build(&uri).await })
+			.await??;
+		Ok((Arc::new(tokio), Arc::new(client)))
 	}
 
 	/// Reopen client connection.
 	pub async fn reconnect(&mut self) -> Result<()> {
-		self.client = Self::build_client(&self.params).await?;
+		self.client = Self::build_client(&self.params).await?.1;
 		Ok(())
 	}
 }
@@ -82,7 +84,8 @@ impl Client {
 impl Client {
 	/// Returns true if client is connected to at least one peer and is in synced state.
 	pub async fn ensure_synced(&self) -> Result<()> {
-		match Ethereum::syncing(&*self.client).await? {
+		self.jsonrpsee_execute(move |client| async move {
+			match Ethereum::syncing(&*client).await? {
 				SyncState::NotSyncing => Ok(()),
 				SyncState::Syncing(syncing) => {
 					let missing_headers = syncing.highest_block.saturating_sub(syncing.current_block);
@@ -93,43 +96,53 @@ impl Client {
 					Ok(())
 				}
 			}
+		})
+		.await
 	}
 
 	/// Estimate gas usage for the given call.
 	pub async fn estimate_gas(&self, call_request: CallRequest) -> Result<U256> {
-		Ok(Ethereum::estimate_gas(&*self.client, call_request).await?)
+		self.jsonrpsee_execute(move |client| async move { Ok(Ethereum::estimate_gas(&*client, call_request).await?) })
+			.await
 	}
 
 	/// Retrieve number of the best known block from the Ethereum node.
 	pub async fn best_block_number(&self) -> Result<u64> {
-		Ok(Ethereum::block_number(&*self.client).await?.as_u64())
+		self.jsonrpsee_execute(move |client| async move { Ok(Ethereum::block_number(&*client).await?.as_u64()) })
+			.await
 	}
 
 	/// Retrieve number of the best known block from the Ethereum node.
 	pub async fn header_by_number(&self, block_number: u64) -> Result<Header> {
+		self.jsonrpsee_execute(move |client| async move {
 			let get_full_tx_objects = false;
-		let header = Ethereum::get_block_by_number(&*self.client, block_number, get_full_tx_objects).await?;
+			let header = Ethereum::get_block_by_number(&*client, block_number, get_full_tx_objects).await?;
 			match header.number.is_some() && header.hash.is_some() && header.logs_bloom.is_some() {
 				true => Ok(header),
 				false => Err(Error::IncompleteHeader),
 			}
+		})
+		.await
 	}
 
 	/// Retrieve block header by its hash from Ethereum node.
 	pub async fn header_by_hash(&self, hash: H256) -> Result<Header> {
+		self.jsonrpsee_execute(move |client| async move {
 			let get_full_tx_objects = false;
-		let header = Ethereum::get_block_by_hash(&*self.client, hash, get_full_tx_objects).await?;
+			let header = Ethereum::get_block_by_hash(&*client, hash, get_full_tx_objects).await?;
 			match header.number.is_some() && header.hash.is_some() && header.logs_bloom.is_some() {
 				true => Ok(header),
 				false => Err(Error::IncompleteHeader),
 			}
+		})
+		.await
 	}
 
 	/// Retrieve block header and its transactions by its number from Ethereum node.
 	pub async fn header_by_number_with_transactions(&self, number: u64) -> Result<HeaderWithTransactions> {
+		self.jsonrpsee_execute(move |client| async move {
 			let get_full_tx_objects = true;
-		let header =
-			Ethereum::get_block_by_number_with_transactions(&*self.client, number, get_full_tx_objects).await?;
+			let header = Ethereum::get_block_by_number_with_transactions(&*client, number, get_full_tx_objects).await?;
 
 			let is_complete_header = header.number.is_some() && header.hash.is_some() && header.logs_bloom.is_some();
 			if !is_complete_header {
@@ -142,12 +155,15 @@ impl Client {
 			}
 
 			Ok(header)
+		})
+		.await
 	}
 
 	/// Retrieve block header and its transactions by its hash from Ethereum node.
 	pub async fn header_by_hash_with_transactions(&self, hash: H256) -> Result<HeaderWithTransactions> {
+		self.jsonrpsee_execute(move |client| async move {
 			let get_full_tx_objects = true;
-		let header = Ethereum::get_block_by_hash_with_transactions(&*self.client, hash, get_full_tx_objects).await?;
+			let header = Ethereum::get_block_by_hash_with_transactions(&*client, hash, get_full_tx_objects).await?;
 
 			let is_complete_header = header.number.is_some() && header.hash.is_some() && header.logs_bloom.is_some();
 			if !is_complete_header {
@@ -160,35 +176,61 @@ impl Client {
 			}
 
 			Ok(header)
+		})
+		.await
 	}
 
 	/// Retrieve transaction by its hash from Ethereum node.
 	pub async fn transaction_by_hash(&self, hash: H256) -> Result<Option<Transaction>> {
-		Ok(Ethereum::transaction_by_hash(&*self.client, hash).await?)
+		self.jsonrpsee_execute(move |client| async move { Ok(Ethereum::transaction_by_hash(&*client, hash).await?) })
+			.await
 	}
 
 	/// Retrieve transaction receipt by transaction hash.
 	pub async fn transaction_receipt(&self, transaction_hash: H256) -> Result<Receipt> {
-		Ok(Ethereum::get_transaction_receipt(&*self.client, transaction_hash).await?)
+		self.jsonrpsee_execute(move |client| async move {
+			Ok(Ethereum::get_transaction_receipt(&*client, transaction_hash).await?)
+		})
+		.await
 	}
 
 	/// Get the nonce of the given account.
 	pub async fn account_nonce(&self, address: Address) -> Result<U256> {
-		Ok(Ethereum::get_transaction_count(&*self.client, address).await?)
+		self.jsonrpsee_execute(
+			move |client| async move { Ok(Ethereum::get_transaction_count(&*client, address).await?) },
+		)
+		.await
 	}
 
 	/// Submit an Ethereum transaction.
 	///
 	/// The transaction must already be signed before sending it through this method.
 	pub async fn submit_transaction(&self, signed_raw_tx: SignedRawTx) -> Result<TransactionHash> {
+		self.jsonrpsee_execute(move |client| async move {
 			let transaction = Bytes(signed_raw_tx);
-		let tx_hash = Ethereum::submit_transaction(&*self.client, transaction).await?;
+			let tx_hash = Ethereum::submit_transaction(&*client, transaction).await?;
 			log::trace!(target: "bridge", "Sent transaction to Ethereum node: {:?}", tx_hash);
 			Ok(tx_hash)
+		})
+		.await
 	}
 
 	/// Call Ethereum smart contract.
 	pub async fn eth_call(&self, call_transaction: CallRequest) -> Result<Bytes> {
-		Ok(Ethereum::call(&*self.client, call_transaction).await?)
+		self.jsonrpsee_execute(move |client| async move { Ok(Ethereum::call(&*client, call_transaction).await?) })
+			.await
+	}
+
+	/// Execute jsonrpsee future in tokio context.
+	async fn jsonrpsee_execute<MF, F, T>(&self, make_jsonrpsee_future: MF) -> Result<T>
+	where
+		MF: FnOnce(Arc<RpcClient>) -> F + Send + 'static,
+		F: Future<Output = Result<T>> + Send,
+		T: Send + 'static,
+	{
+		let client = self.client.clone();
+		self.tokio
+			.spawn(async move { make_jsonrpsee_future(client).await })
+			.await?
 	}
 }

bridges/relays/client-ethereum/src/error.rs

@@ -28,6 +28,8 @@ pub type Result<T> = std::result::Result<T, Error>;
 /// an Ethereum node through RPC.
 #[derive(Debug)]
 pub enum Error {
+	/// IO error.
+	Io(std::io::Error),
 	/// An error that can occur when making an HTTP request to
 	/// an JSON-RPC client.
 	RpcError(RpcError),
@@ -45,6 +47,8 @@ pub enum Error {
 	/// The client we're connected to is not synced, so we can't rely on its state. Contains
 	/// number of unsynced headers.
 	ClientNotSynced(U256),
+	/// Custom logic error.
+	Custom(String),
 }
 
 impl From<RpcError> for Error {
@@ -53,6 +57,18 @@ impl From<RpcError> for Error {
 	}
 }
 
+impl From<std::io::Error> for Error {
+	fn from(error: std::io::Error) -> Self {
+		Error::Io(error)
+	}
+}
+
+impl From<tokio::task::JoinError> for Error {
+	fn from(error: tokio::task::JoinError) -> Self {
+		Error::Custom(format!("Failed to wait tokio task: {}", error))
+	}
+}
+
 impl MaybeConnectionError for Error {
 	fn is_connection_error(&self) -> bool {
 		matches!(
@@ -68,6 +84,7 @@ impl MaybeConnectionError for Error {
 impl ToString for Error {
 	fn to_string(&self) -> String {
 		match self {
+			Self::Io(e) => e.to_string(),
 			Self::RpcError(e) => e.to_string(),
 			Self::ResponseParseFailed(e) => e.to_string(),
 			Self::IncompleteHeader => {
@@ -80,6 +97,7 @@ impl ToString for Error {
 			Self::ClientNotSynced(missing_headers) => {
 				format!("Ethereum client is not synced: syncing {} headers", missing_headers)
 			}
+			Self::Custom(ref e) => e.clone(),
 		}
 	}
 }

bridges/relays/client-substrate/Cargo.toml

@@ -14,6 +14,7 @@ jsonrpsee-ws-client = "0.2"
 log = "0.4.11"
 num-traits = "0.2"
 rand = "0.7"
+tokio = "1.8"
 
 # Bridge dependencies
 

bridges/relays/client-substrate/src/client.rs

@@ -32,13 +32,13 @@ use relay_utils::relay_loop::RECONNECT_DELAY;
 use sp_core::{storage::StorageKey, Bytes};
 use sp_trie::StorageProof;
 use sp_version::RuntimeVersion;
-use std::convert::TryFrom;
+use std::{convert::TryFrom, future::Future};
 
 const SUB_API_GRANDPA_AUTHORITIES: &str = "GrandpaApi_grandpa_authorities";
 const MAX_SUBSCRIPTION_CAPACITY: usize = 4096;
 
 /// Opaque justifications subscription type.
-pub type JustificationsSubscription = Subscription<Bytes>;
+pub struct JustificationsSubscription(tokio::runtime::Handle, Arc<Mutex<Subscription<Bytes>>>);
 
 /// Opaque GRANDPA authorities set.
 pub type OpaqueGrandpaAuthoritiesSet = Vec<u8>;
@@ -47,6 +47,8 @@ pub type OpaqueGrandpaAuthoritiesSet = Vec<u8>;
 ///
 /// Cloning `Client` is a cheap operation.
 pub struct Client<C: Chain> {
+	/// Tokio runtime handle.
+	tokio: Arc<tokio::runtime::Runtime>,
 	/// Client connection params.
 	params: ConnectionParams,
 	/// Substrate RPC client.
@@ -62,6 +64,7 @@ pub struct Client<C: Chain> {
 impl<C: Chain> Clone for Client<C> {
 	fn clone(&self) -> Self {
 		Client {
+			tokio: self.tokio.clone(),
 			params: self.params.clone(),
 			client: self.client.clone(),
 			genesis_hash: self.genesis_hash,
@@ -103,12 +106,16 @@ impl<C: Chain> Client<C> {
 	/// Try to connect to Substrate node over websocket. Returns Substrate RPC client if connection
 	/// has been established or error otherwise.
 	pub async fn try_connect(params: ConnectionParams) -> Result<Self> {
-		let client = Self::build_client(params.clone()).await?;
+		let (tokio, client) = Self::build_client(params.clone()).await?;
 
 		let number: C::BlockNumber = Zero::zero();
-		let genesis_hash = Substrate::<C>::chain_get_block_hash(&*client, number).await?;
+		let genesis_hash_client = client.clone();
+		let genesis_hash = tokio
+			.spawn(async move { Substrate::<C>::chain_get_block_hash(&*genesis_hash_client, number).await })
+			.await??;
 
 		Ok(Self {
+			tokio,
 			params,
 			client,
 			genesis_hash,
@@ -118,37 +125,45 @@ impl<C: Chain> Client<C> {
 
 	/// Reopen client connection.
 	pub async fn reconnect(&mut self) -> Result<()> {
-		self.client = Self::build_client(self.params.clone()).await?;
+		self.client = Self::build_client(self.params.clone()).await?.1;
 		Ok(())
 	}
 
 	/// Build client to use in connection.
-	async fn build_client(params: ConnectionParams) -> Result<Arc<RpcClient>> {
+	async fn build_client(params: ConnectionParams) -> Result<(Arc<tokio::runtime::Runtime>, Arc<RpcClient>)> {
+		let tokio = tokio::runtime::Runtime::new()?;
 		let uri = format!(
 			"{}://{}:{}",
 			if params.secure { "wss" } else { "ws" },
 			params.host,
 			params.port,
 		);
-		let client = RpcClientBuilder::default()
+		let client = tokio
+			.spawn(async move {
+				RpcClientBuilder::default()
 					.max_notifs_per_subscription(MAX_SUBSCRIPTION_CAPACITY)
 					.build(&uri)
-			.await?;
+					.await
+			})
+			.await??;
 
-		Ok(Arc::new(client))
+		Ok((Arc::new(tokio), Arc::new(client)))
 	}
 }
 
 impl<C: Chain> Client<C> {
 	/// Returns true if client is connected to at least one peer and is in synced state.
 	pub async fn ensure_synced(&self) -> Result<()> {
-		let health = Substrate::<C>::system_health(&*self.client).await?;
+		self.jsonrpsee_execute(|client| async move {
+			let health = Substrate::<C>::system_health(&*client).await?;
 			let is_synced = !health.is_syncing && (!health.should_have_peers || health.peers > 0);
 			if is_synced {
 				Ok(())
 			} else {
 				Err(Error::ClientNotSynced(health))
 			}
+		})
+		.await
 	}
 
 	/// Return hash of the genesis block.
@@ -158,7 +173,8 @@ impl<C: Chain> Client<C> {
 
 	/// Return hash of the best finalized block.
 	pub async fn best_finalized_header_hash(&self) -> Result<C::Hash> {
-		Ok(Substrate::<C>::chain_get_finalized_head(&*self.client).await?)
+		self.jsonrpsee_execute(|client| async move { Ok(Substrate::<C>::chain_get_finalized_head(&*client).await?) })
+			.await
 	}
 
 	/// Returns the best Substrate header.
@@ -166,12 +182,16 @@ impl<C: Chain> Client<C> {
 	where
 		C::Header: DeserializeOwned,
 	{
-		Ok(Substrate::<C>::chain_get_header(&*self.client, None).await?)
+		self.jsonrpsee_execute(|client| async move { Ok(Substrate::<C>::chain_get_header(&*client, None).await?) })
+			.await
 	}
 
 	/// Get a Substrate block from its hash.
 	pub async fn get_block(&self, block_hash: Option<C::Hash>) -> Result<C::SignedBlock> {
-		Ok(Substrate::<C>::chain_get_block(&*self.client, block_hash).await?)
+		self.jsonrpsee_execute(
+			move |client| async move { Ok(Substrate::<C>::chain_get_block(&*client, block_hash).await?) },
+		)
+		.await
 	}
 
 	/// Get a Substrate header by its hash.
@@ -179,12 +199,18 @@ impl<C: Chain> Client<C> {
 	where
 		C::Header: DeserializeOwned,
 	{
-		Ok(Substrate::<C>::chain_get_header(&*self.client, block_hash).await?)
+		self.jsonrpsee_execute(move |client| async move {
+			Ok(Substrate::<C>::chain_get_header(&*client, block_hash).await?)
+		})
+		.await
 	}
 
 	/// Get a Substrate block hash by its number.
 	pub async fn block_hash_by_number(&self, number: C::BlockNumber) -> Result<C::Hash> {
-		Ok(Substrate::<C>::chain_get_block_hash(&*self.client, number).await?)
+		self.jsonrpsee_execute(move |client| async move {
+			Ok(Substrate::<C>::chain_get_block_hash(&*client, number).await?)
+		})
+		.await
 	}
 
 	/// Get a Substrate header by its number.
@@ -193,20 +219,25 @@ impl<C: Chain> Client<C> {
 		C::Header: DeserializeOwned,
 	{
 		let block_hash = Self::block_hash_by_number(self, block_number).await?;
-		Ok(Self::header_by_hash(self, block_hash).await?)
+		let header_by_hash = Self::header_by_hash(self, block_hash).await?;
+		Ok(header_by_hash)
 	}
 
 	/// Return runtime version.
 	pub async fn runtime_version(&self) -> Result<RuntimeVersion> {
-		Ok(Substrate::<C>::state_runtime_version(&*self.client).await?)
+		self.jsonrpsee_execute(move |client| async move { Ok(Substrate::<C>::state_runtime_version(&*client).await?) })
+			.await
 	}
 
 	/// Read value from runtime storage.
-	pub async fn storage_value<T: Decode>(&self, storage_key: StorageKey) -> Result<Option<T>> {
-		Substrate::<C>::state_get_storage(&*self.client, storage_key)
+	pub async fn storage_value<T: Send + Decode + 'static>(&self, storage_key: StorageKey) -> Result<Option<T>> {
+		self.jsonrpsee_execute(move |client| async move {
+			Substrate::<C>::state_get_storage(&*client, storage_key)
 				.await?
 				.map(|encoded_value| T::decode(&mut &encoded_value.0[..]).map_err(Error::ResponseParseFailed))
 				.transpose()
+		})
+		.await
 	}
 
 	/// Return native tokens balance of the account.
@@ -214,30 +245,39 @@ impl<C: Chain> Client<C> {
 	where
 		C: ChainWithBalances,
 	{
+		self.jsonrpsee_execute(move |client| async move {
 			let storage_key = C::account_info_storage_key(&account);
-		let encoded_account_data = Substrate::<C>::state_get_storage(&*self.client, storage_key)
+			let encoded_account_data = Substrate::<C>::state_get_storage(&*client, storage_key)
 				.await?
 				.ok_or(Error::AccountDoesNotExist)?;
 			let decoded_account_data =
 				AccountInfo::<C::Index, AccountData<C::Balance>>::decode(&mut &encoded_account_data.0[..])
 					.map_err(Error::ResponseParseFailed)?;
 			Ok(decoded_account_data.data.free)
+		})
+		.await
 	}
 
 	/// Get the nonce of the given Substrate account.
 	///
 	/// Note: It's the caller's responsibility to make sure `account` is a valid ss58 address.
 	pub async fn next_account_index(&self, account: C::AccountId) -> Result<C::Index> {
-		Ok(Substrate::<C>::system_account_next_index(&*self.client, account).await?)
+		self.jsonrpsee_execute(move |client| async move {
+			Ok(Substrate::<C>::system_account_next_index(&*client, account).await?)
+		})
+		.await
 	}
 
 	/// Submit unsigned extrinsic for inclusion in a block.
 	///
 	/// Note: The given transaction needs to be SCALE encoded beforehand.
 	pub async fn submit_unsigned_extrinsic(&self, transaction: Bytes) -> Result<C::Hash> {
-		let tx_hash = Substrate::<C>::author_submit_extrinsic(&*self.client, transaction).await?;
+		self.jsonrpsee_execute(move |client| async move {
+			let tx_hash = Substrate::<C>::author_submit_extrinsic(&*client, transaction).await?;
 			log::trace!(target: "bridge", "Sent transaction to Substrate node: {:?}", tx_hash);
 			Ok(tx_hash)
+		})
+		.await
 	}
 
 	/// Submit an extrinsic signed by given account.
@@ -250,19 +290,23 @@ impl<C: Chain> Client<C> {
 	pub async fn submit_signed_extrinsic(
 		&self,
 		extrinsic_signer: C::AccountId,
-		prepare_extrinsic: impl FnOnce(C::Index) -> Bytes,
+		prepare_extrinsic: impl FnOnce(C::Index) -> Bytes + Send + 'static,
 	) -> Result<C::Hash> {
 		let _guard = self.submit_signed_extrinsic_lock.lock().await;
 		let transaction_nonce = self.next_account_index(extrinsic_signer).await?;
+		self.jsonrpsee_execute(move |client| async move {
 			let extrinsic = prepare_extrinsic(transaction_nonce);
-		let tx_hash = Substrate::<C>::author_submit_extrinsic(&*self.client, extrinsic).await?;
+			let tx_hash = Substrate::<C>::author_submit_extrinsic(&*client, extrinsic).await?;
 			log::trace!(target: "bridge", "Sent transaction to {} node: {:?}", C::NAME, tx_hash);
 			Ok(tx_hash)
+		})
+		.await
 	}
 
 	/// Estimate fee that will be spent on given extrinsic.
 	pub async fn estimate_extrinsic_fee(&self, transaction: Bytes) -> Result<C::Balance> {
-		let fee_details = Substrate::<C>::payment_query_fee_details(&*self.client, transaction, None).await?;
+		self.jsonrpsee_execute(move |client| async move {
+			let fee_details = Substrate::<C>::payment_query_fee_details(&*client, transaction, None).await?;
 			let inclusion_fee = fee_details
 				.inclusion_fee
 				.map(|inclusion_fee| {
@@ -278,43 +322,85 @@ impl<C: Chain> Client<C> {
 				})
 				.unwrap_or_else(Zero::zero);
 			Ok(inclusion_fee)
+		})
+		.await
 	}
 
 	/// Get the GRANDPA authority set at given block.
 	pub async fn grandpa_authorities_set(&self, block: C::Hash) -> Result<OpaqueGrandpaAuthoritiesSet> {
+		self.jsonrpsee_execute(move |client| async move {
 			let call = SUB_API_GRANDPA_AUTHORITIES.to_string();
 			let data = Bytes(Vec::new());
 
-		let encoded_response = Substrate::<C>::state_call(&*self.client, call, data, Some(block)).await?;
+			let encoded_response = Substrate::<C>::state_call(&*client, call, data, Some(block)).await?;
 			let authority_list = encoded_response.0;
 
 			Ok(authority_list)
+		})
+		.await
 	}
 
 	/// Execute runtime call at given block.
 	pub async fn state_call(&self, method: String, data: Bytes, at_block: Option<C::Hash>) -> Result<Bytes> {
-		Substrate::<C>::state_call(&*self.client, method, data, at_block)
+		self.jsonrpsee_execute(move |client| async move {
+			Substrate::<C>::state_call(&*client, method, data, at_block)
 				.await
 				.map_err(Into::into)
+		})
+		.await
 	}
 
 	/// Returns storage proof of given storage keys.
 	pub async fn prove_storage(&self, keys: Vec<StorageKey>, at_block: C::Hash) -> Result<StorageProof> {
-		Substrate::<C>::state_prove_storage(&*self.client, keys, Some(at_block))
+		self.jsonrpsee_execute(move |client| async move {
+			Substrate::<C>::state_prove_storage(&*client, keys, Some(at_block))
 				.await
 				.map(|proof| StorageProof::new(proof.proof.into_iter().map(|b| b.0).collect()))
 				.map_err(Into::into)
+		})
+		.await
 	}
 
 	/// Return new justifications stream.
 	pub async fn subscribe_justifications(&self) -> Result<JustificationsSubscription> {
-		Ok(self
-			.client
+		let subscription = self
+			.jsonrpsee_execute(move |client| async move {
+				Ok(client
 					.subscribe(
 						"grandpa_subscribeJustifications",
 						JsonRpcParams::NoParams,
 						"grandpa_unsubscribeJustifications",
 					)
 					.await?)
+			})
+			.await?;
+		Ok(JustificationsSubscription(
+			self.tokio.handle().clone(),
+			Arc::new(Mutex::new(subscription)),
+		))
+	}
+
+	/// Execute jsonrpsee future in tokio context.
+	async fn jsonrpsee_execute<MF, F, T>(&self, make_jsonrpsee_future: MF) -> Result<T>
+	where
+		MF: FnOnce(Arc<RpcClient>) -> F + Send + 'static,
+		F: Future<Output = Result<T>> + Send,
+		T: Send + 'static,
+	{
+		let client = self.client.clone();
+		self.tokio
+			.spawn(async move { make_jsonrpsee_future(client).await })
+			.await?
+	}
+}
+
+impl JustificationsSubscription {
+	/// Return next justification from the subscription.
+	pub async fn next(&self) -> Result<Option<Bytes>> {
+		let subscription = self.1.clone();
+		self.0
+			.spawn(async move { subscription.lock().await.next().await })
+			.await?
+			.map_err(Error::RpcError)
 	}
 }

bridges/relays/client-substrate/src/error.rs

@@ -27,6 +27,8 @@ pub type Result<T> = std::result::Result<T, Error>;
 /// a Substrate node through RPC.
 #[derive(Debug)]
 pub enum Error {
+	/// IO error.
+	Io(std::io::Error),
 	/// An error that can occur when making a request to
 	/// an JSON-RPC server.
 	RpcError(RpcError),
@@ -49,6 +51,7 @@ pub enum Error {
 impl std::error::Error for Error {
 	fn source(&self) -> Option<&(dyn std::error::Error + 'static)> {
 		match self {
+			Self::Io(ref e) => Some(e),
 			Self::RpcError(ref e) => Some(e),
 			Self::ResponseParseFailed(ref e) => Some(e),
 			Self::UninitializedBridgePallet => None,
@@ -67,6 +70,18 @@ impl From<RpcError> for Error {
 	}
 }
 
+impl From<std::io::Error> for Error {
+	fn from(error: std::io::Error) -> Self {
+		Error::Io(error)
+	}
+}
+
+impl From<tokio::task::JoinError> for Error {
+	fn from(error: tokio::task::JoinError) -> Self {
+		Error::Custom(format!("Failed to wait tokio task: {}", error))
+	}
+}
+
 impl MaybeConnectionError for Error {
 	fn is_connection_error(&self) -> bool {
 		matches!(
@@ -82,6 +97,7 @@ impl MaybeConnectionError for Error {
 impl std::fmt::Display for Error {
 	fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
 		let s = match self {
+			Self::Io(e) => e.to_string(),
 			Self::RpcError(e) => e.to_string(),
 			Self::ResponseParseFailed(e) => e.to_string(),
 			Self::UninitializedBridgePallet => "The Substrate bridge pallet has not been initialized yet.".into(),

bridges/relays/client-substrate/src/finality_source.rs

@@ -132,7 +132,7 @@ where
 	async fn finality_proofs(&self) -> Result<Self::FinalityProofsStream, Error> {
 		Ok(unfold(
 			self.client.clone().subscribe_justifications().await?,
-			move |mut subscription| async move {
+			move |subscription| async move {
 				loop {
 					let log_error = |err| {
 						log::error!(