Migrate to jsonrpsee v2 (#787)

* POC jsonrpsee v2

* POC update ws client

* connect to eth nodes using ws

* fix for subscriptions

* reverted unncecessary changes

* reference jsonrpsee from crates.io

* fixed eth port in deployments

* fmt

* order deps

* remove unnecessary comment

* clone is no longer required for subscriptions

* treat RpcError::Internal as connection error

* resubscribe on terminate

* Update deployments/bridges/poa-rialto/entrypoints/poa-exchange-tx-generator-entrypoint.sh

Co-authored-by: Niklas Adolfsson <niklasadolfsson1@gmail.com>
Co-authored-by: Hernando Castano <HCastano@users.noreply.github.com>

bridges/relays/ethereum-client/Cargo.toml

@@ -10,7 +10,9 @@ bp-eth-poa = { path = "../../primitives/ethereum-poa" }
 codec = { package = "parity-scale-codec", version = "2.0.0" }
 headers-relay = { path = "../headers-relay" }
 hex-literal = "0.3"
-jsonrpsee = { git = "https://github.com/svyatonik/jsonrpsee.git", branch = "shared-client-in-rpc-api", default-features = false, features = ["http"] }
+jsonrpsee-proc-macros = "0.2.0-alpha"
+jsonrpsee-types = "0.2.0-alpha"
+jsonrpsee-ws-client = "0.2.0-alpha"
 libsecp256k1 = { version = "0.3.4", default-features = false, features = ["hmac"] }
 log = "0.4.11"
 relay-utils = { path = "../utils" }

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

@@ -21,9 +21,8 @@ use crate::types::{
 };
 use crate::{ConnectionParams, Error, Result};
 
-use jsonrpsee::raw::RawClient;
-use jsonrpsee::transport::http::HttpTransportClient;
-use jsonrpsee::Client as RpcClient;
+use jsonrpsee_ws_client::{WsClient as RpcClient, WsConfig as RpcConfig};
+use std::sync::Arc;
 
 /// Number of headers missing from the Ethereum node for us to consider node not synced.
 const MAJOR_SYNC_BLOCKS: u64 = 5;
@@ -32,36 +31,36 @@ const MAJOR_SYNC_BLOCKS: u64 = 5;
 #[derive(Clone)]
 pub struct Client {
 	params: ConnectionParams,
-	client: RpcClient,
+	client: Arc<RpcClient>,
 }
 
 impl Client {
 	/// Create a new Ethereum RPC Client.
-	pub fn new(params: ConnectionParams) -> Self {
-		Self {
-			client: Self::build_client(&params),
+	pub async fn new(params: ConnectionParams) -> Result<Self> {
+		Ok(Self {
+			client: Self::build_client(&params).await?,
 			params,
-		}
+		})
 	}
 
 	/// Build client to use in connection.
-	fn build_client(params: &ConnectionParams) -> RpcClient {
-		let uri = format!("http://{}:{}", params.host, params.port);
-		let transport = HttpTransportClient::new(&uri);
-		let raw_client = RawClient::new(transport);
-		raw_client.into()
+	async fn build_client(params: &ConnectionParams) -> Result<Arc<RpcClient>> {
+		let uri = format!("ws://{}:{}", params.host, params.port);
+		let client = RpcClient::new(RpcConfig::with_url(&uri)).await?;
+		Ok(Arc::new(client))
 	}
 
 	/// Reopen client connection.
-	pub fn reconnect(&mut self) {
-		self.client = Self::build_client(&self.params);
+	pub async fn reconnect(&mut self) -> Result<()> {
+		self.client = Self::build_client(&self.params).await?;
+		Ok(())
 	}
 }
 
 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? {
+		match Ethereum::syncing(&*self.client).await? {
 			SyncState::NotSyncing => Ok(()),
 			SyncState::Syncing(syncing) => {
 				let missing_headers = syncing.highest_block.saturating_sub(syncing.current_block);
@@ -76,18 +75,18 @@ impl Client {
 
 	/// 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?)
+		Ok(Ethereum::estimate_gas(&*self.client, call_request).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())
+		Ok(Ethereum::block_number(&*self.client).await?.as_u64())
 	}
 
 	/// Retrieve number of the best known block from the Ethereum node.
 	pub async fn header_by_number(&self, block_number: u64) -> Result<Header> {
 		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(&*self.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),
@@ -97,7 +96,7 @@ impl Client {
 	/// Retrieve block header by its hash from Ethereum node.
 	pub async fn header_by_hash(&self, hash: H256) -> Result<Header> {
 		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(&*self.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),
@@ -107,7 +106,8 @@ impl Client {
 	/// 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> {
 		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(&*self.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 {
@@ -125,7 +125,7 @@ impl Client {
 	/// 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> {
 		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(&*self.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 {
@@ -142,17 +142,17 @@ impl Client {
 
 	/// 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?)
+		Ok(Ethereum::transaction_by_hash(&*self.client, hash).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?)
+		Ok(Ethereum::get_transaction_receipt(&*self.client, transaction_hash).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?)
+		Ok(Ethereum::get_transaction_count(&*self.client, address).await?)
 	}
 
 	/// Submit an Ethereum transaction.
@@ -160,13 +160,13 @@ impl Client {
 	/// The transaction must already be signed before sending it through this method.
 	pub async fn submit_transaction(&self, signed_raw_tx: SignedRawTx) -> Result<TransactionHash> {
 		let transaction = Bytes(signed_raw_tx);
-		let tx_hash = Ethereum::submit_transaction(&self.client, transaction).await?;
+		let tx_hash = Ethereum::submit_transaction(&*self.client, transaction).await?;
 		log::trace!(target: "bridge", "Sent transaction to Ethereum node: {:?}", tx_hash);
 		Ok(tx_hash)
 	}
 
 	/// Call Ethereum smart contract.
 	pub async fn eth_call(&self, call_transaction: CallRequest) -> Result<Bytes> {
-		Ok(Ethereum::call(&self.client, call_transaction).await?)
+		Ok(Ethereum::call(&*self.client, call_transaction).await?)
 	}
 }

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

@@ -18,7 +18,7 @@
 
 use crate::types::U256;
 
-use jsonrpsee::client::RequestError;
+use jsonrpsee_types::error::Error as RpcError;
 use relay_utils::MaybeConnectionError;
 
 /// Result type used by Ethereum client.
@@ -30,7 +30,7 @@ pub type Result<T> = std::result::Result<T, Error>;
 pub enum Error {
 	/// An error that can occur when making an HTTP request to
 	/// an JSON-RPC client.
-	Request(RequestError),
+	RpcError(RpcError),
 	/// Failed to parse response.
 	ResponseParseFailed(String),
 	/// We have received a header with missing fields.
@@ -47,9 +47,9 @@ pub enum Error {
 	ClientNotSynced(U256),
 }
 
-impl From<RequestError> for Error {
-	fn from(error: RequestError) -> Self {
-		Error::Request(error)
+impl From<RpcError> for Error {
+	fn from(error: RpcError) -> Self {
+		Error::RpcError(error)
 	}
 }
 
@@ -57,7 +57,11 @@ impl MaybeConnectionError for Error {
 	fn is_connection_error(&self) -> bool {
 		matches!(
 			*self,
-			Error::Request(RequestError::TransportError(_)) | Error::ClientNotSynced(_),
+			Error::RpcError(RpcError::TransportError(_))
+				// right now if connection to the ws server is dropped (after it is already established),
+				// we're getting this error
+				| Error::RpcError(RpcError::Internal(_))
+				| Error::ClientNotSynced(_),
 		)
 	}
 }
@@ -65,7 +69,7 @@ impl MaybeConnectionError for Error {
 impl ToString for Error {
 	fn to_string(&self) -> String {
 		match self {
-			Self::Request(e) => e.to_string(),
+			Self::RpcError(e) => e.to_string(),
 			Self::ResponseParseFailed(e) => e.to_string(),
 			Self::IncompleteHeader => {
 				"Incomplete Ethereum Header Received (missing some of required fields - hash, number, logs_bloom)"

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

@@ -29,12 +29,12 @@ pub use crate::sign::{sign_and_submit_transaction, SigningParams};
 
 pub mod types;
 
-/// Ethereum connection params.
+/// Ethereum-over-websocket connection params.
 #[derive(Debug, Clone)]
 pub struct ConnectionParams {
-	/// Ethereum RPC host.
+	/// Websocket server hostname.
 	pub host: String,
-	/// Ethereum RPC port.
+	/// Websocket server TCP port.
 	pub port: u16,
 }
 
@@ -42,7 +42,7 @@ impl Default for ConnectionParams {
 	fn default() -> Self {
 		ConnectionParams {
 			host: "localhost".into(),
-			port: 8545,
+			port: 8546,
 		}
 	}
 }

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

@@ -26,7 +26,7 @@ use crate::types::{
 	H256, U256, U64,
 };
 
-jsonrpsee::rpc_api! {
+jsonrpsee_proc_macros::rpc_client_api! {
 	pub(crate) Ethereum {
 		#[rpc(method = "eth_syncing", positional_params)]
 		fn syncing() -> SyncState;

bridges/relays/ethereum/src/cli.yml

@@ -9,17 +9,17 @@ subcommands:
             - eth-host: &eth-host
                 long: eth-host
                 value_name: ETH_HOST
-                help: Connect to Ethereum node at given host.
+                help: Connect to Ethereum node websocket server at given host.
                 takes_value: true
             - eth-port: &eth-port
                 long: eth-port
                 value_name: ETH_PORT
-                help: Connect to Ethereum node at given port.
+                help: Connect to Ethereum node websocket server at given port.
                 takes_value: true
             - sub-host: &sub-host
                 long: sub-host
                 value_name: SUB_HOST
-                help: Connect to Substrate node at given host.
+                help: Connect to Substrate node websocket server at given host.
                 takes_value: true
             - sub-port: &sub-port
                 long: sub-port

bridges/relays/ethereum/src/ethereum_deploy_contract.rs

@@ -62,7 +62,7 @@ pub fn run(params: EthereumDeployContractParams) {
 	} = params;
 
 	let result = local_pool.run_until(async move {
-		let eth_client = EthereumClient::new(eth_params);
+		let eth_client = EthereumClient::new(eth_params).await.map_err(RpcError::Ethereum)?;
 		let sub_client = SubstrateClient::<Rialto>::new(sub_params).await.map_err(RpcError::Substrate)?;
 
 		let (initial_header_id, initial_header) = prepare_initial_header(&sub_client, sub_initial_header).await?;

bridges/relays/ethereum/src/ethereum_exchange.rs

@@ -130,8 +130,7 @@ impl RelayClient for EthereumTransactionsSource {
 	type Error = RpcError;
 
 	async fn reconnect(&mut self) -> Result<(), RpcError> {
-		self.client.reconnect();
-		Ok(())
+		self.client.reconnect().await.map_err(Into::into)
 	}
 }
 
@@ -305,7 +304,7 @@ fn run_single_transaction_relay(params: EthereumExchangeParams, eth_tx_hash: H25
 	} = params;
 
 	let result = local_pool.run_until(async move {
-		let eth_client = EthereumClient::new(eth_params);
+		let eth_client = EthereumClient::new(eth_params).await.map_err(RpcError::Ethereum)?;
 		let sub_client = SubstrateClient::<Rialto>::new(sub_params)
 			.await
 			.map_err(RpcError::Substrate)?;
@@ -351,7 +350,8 @@ fn run_auto_transactions_relay_loop(params: EthereumExchangeParams, eth_start_wi
 	} = params;
 
 	let do_run_loop = move || -> Result<(), String> {
-		let eth_client = EthereumClient::new(eth_params);
+		let eth_client = async_std::task::block_on(EthereumClient::new(eth_params))
+			.map_err(|err| format!("Error starting Ethereum client: {:?}", err))?;
 		let sub_client = async_std::task::block_on(SubstrateClient::<Rialto>::new(sub_params))
 			.map_err(|err| format!("Error starting Substrate client: {:?}", err))?;
 

bridges/relays/ethereum/src/ethereum_exchange_submit.rs

@@ -54,7 +54,9 @@ pub fn run(params: EthereumExchangeSubmitParams) {
 	} = params;
 
 	let result: Result<_, String> = local_pool.run_until(async move {
-		let eth_client = EthereumClient::new(eth_params);
+		let eth_client = EthereumClient::new(eth_params)
+			.await
+			.map_err(|err| format!("error connecting to Ethereum node: {:?}", err))?;
 
 		let eth_signer_address = secret_to_address(&eth_sign.signer);
 		let sub_recipient_encoded = sub_recipient;

bridges/relays/ethereum/src/ethereum_sync_loop.rs

@@ -122,8 +122,7 @@ impl RelayClient for EthereumHeadersSource {
 	type Error = RpcError;
 
 	async fn reconnect(&mut self) -> Result<(), RpcError> {
-		self.client.reconnect();
-		Ok(())
+		self.client.reconnect().await.map_err(Into::into)
 	}
 }
 
@@ -259,8 +258,8 @@ pub fn run(params: EthereumSyncParams) -> Result<(), RpcError> {
 		instance,
 	} = params;
 
-	let eth_client = EthereumClient::new(eth_params);
-	let sub_client = async_std::task::block_on(async { SubstrateClient::<Rialto>::new(sub_params).await })?;
+	let eth_client = async_std::task::block_on(EthereumClient::new(eth_params))?;
+	let sub_client = async_std::task::block_on(SubstrateClient::<Rialto>::new(sub_params))?;
 
 	let sign_sub_transactions = match sync_params.target_tx_mode {
 		TargetTransactionMode::Signed | TargetTransactionMode::Backup => true,

bridges/relays/ethereum/src/substrate_sync_loop.rs

@@ -123,8 +123,7 @@ impl RelayClient for EthereumHeadersTarget {
 	type Error = RpcError;
 
 	async fn reconnect(&mut self) -> Result<(), RpcError> {
-		self.client.reconnect();
-		Ok(())
+		self.client.reconnect().await.map_err(Into::into)
 	}
 }
 
@@ -174,8 +173,8 @@ pub fn run(params: SubstrateSyncParams) -> Result<(), RpcError> {
 		metrics_params,
 	} = params;
 
-	let eth_client = EthereumClient::new(eth_params);
-	let sub_client = async_std::task::block_on(async { SubstrateClient::<Rialto>::new(sub_params).await })?;
+	let eth_client = async_std::task::block_on(EthereumClient::new(eth_params))?;
+	let sub_client = async_std::task::block_on(SubstrateClient::<Rialto>::new(sub_params))?;
 
 	let target = EthereumHeadersTarget::new(eth_client, eth_contract_address, eth_sign);
 	let source = SubstrateHeadersSource::new(sub_client);

bridges/relays/substrate-client/Cargo.toml

@@ -9,7 +9,9 @@ license = "GPL-3.0-or-later WITH Classpath-exception-2.0"
 async-std = "1.6.5"
 async-trait = "0.1.40"
 codec = { package = "parity-scale-codec", version = "2.0.0" }
-jsonrpsee = { git = "https://github.com/svyatonik/jsonrpsee.git", branch = "shared-client-in-rpc-api", default-features = false, features = ["ws"] }
+jsonrpsee-proc-macros = "0.2.0-alpha"
+jsonrpsee-types = "0.2.0-alpha"
+jsonrpsee-ws-client = "0.2.0-alpha"
 log = "0.4.11"
 num-traits = "0.2"
 rand = "0.7"

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

@@ -18,7 +18,7 @@ use crate::client::Client;
 
 use bp_runtime::Chain as ChainBase;
 use frame_support::Parameter;
-use jsonrpsee::common::{DeserializeOwned, Serialize};
+use jsonrpsee_types::jsonrpc::{DeserializeOwned, Serialize};
 use num_traits::{CheckedSub, Zero};
 use sp_core::{storage::StorageKey, Pair};
 use sp_runtime::{

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

@@ -24,10 +24,8 @@ use bp_message_lane::{LaneId, MessageNonce};
 use bp_runtime::InstanceId;
 use codec::Decode;
 use frame_system::AccountInfo;
-use jsonrpsee::common::DeserializeOwned;
-use jsonrpsee::raw::RawClient;
-use jsonrpsee::transport::ws::WsTransportClient;
-use jsonrpsee::{client::Subscription, Client as RpcClient};
+use jsonrpsee_types::{jsonrpc::DeserializeOwned, traits::SubscriptionClient};
+use jsonrpsee_ws_client::{WsClient as RpcClient, WsConfig as RpcConfig, WsSubscription as Subscription};
 use num_traits::Zero;
 use pallet_balances::AccountData;
 use sp_core::Bytes;
@@ -36,6 +34,7 @@ use sp_version::RuntimeVersion;
 use std::ops::RangeInclusive;
 
 const SUB_API_GRANDPA_AUTHORITIES: &str = "GrandpaApi_grandpa_authorities";
+const MAX_SUBSCRIPTION_CAPACITY: usize = 4096;
 
 /// Opaque justifications subscription type.
 pub type JustificationsSubscription = Subscription<Bytes>;
@@ -79,7 +78,7 @@ impl<C: Chain> Client<C> {
 		let 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 = Substrate::<C>::chain_get_block_hash(&client, number).await?;
 
 		Ok(Self {
 			params,
@@ -97,16 +96,17 @@ impl<C: Chain> Client<C> {
 	/// Build client to use in connection.
 	async fn build_client(params: ConnectionParams) -> Result<RpcClient> {
 		let uri = format!("ws://{}:{}", params.host, params.port);
-		let transport = WsTransportClient::new(&uri).await?;
-		let raw_client = RawClient::new(transport);
-		Ok(raw_client.into())
+		let mut config = RpcConfig::with_url(&uri);
+		config.max_subscription_capacity = MAX_SUBSCRIPTION_CAPACITY;
+		let client = RpcClient::new(config).await?;
+		Ok(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?;
+		let health = Substrate::<C>::system_health(&self.client).await?;
 		let is_synced = !health.is_syncing && (!health.should_have_peers || health.peers > 0);
 		if is_synced {
 			Ok(())
@@ -122,7 +122,7 @@ 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?)
+		Ok(Substrate::<C>::chain_get_finalized_head(&self.client).await?)
 	}
 
 	/// Returns the best Substrate header.
@@ -130,12 +130,12 @@ impl<C: Chain> Client<C> {
 	where
 		C::Header: DeserializeOwned,
 	{
-		Ok(Substrate::<C, _, _>::chain_get_header(&self.client, None).await?)
+		Ok(Substrate::<C>::chain_get_header(&self.client, None).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?)
+		Ok(Substrate::<C>::chain_get_block(&self.client, block_hash).await?)
 	}
 
 	/// Get a Substrate header by its hash.
@@ -143,12 +143,12 @@ impl<C: Chain> Client<C> {
 	where
 		C::Header: DeserializeOwned,
 	{
-		Ok(Substrate::<C, _, _>::chain_get_header(&self.client, block_hash).await?)
+		Ok(Substrate::<C>::chain_get_header(&self.client, block_hash).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?)
+		Ok(Substrate::<C>::chain_get_block_hash(&self.client, number).await?)
 	}
 
 	/// Get a Substrate header by its number.
@@ -162,7 +162,7 @@ impl<C: Chain> Client<C> {
 
 	/// Return runtime version.
 	pub async fn runtime_version(&self) -> Result<RuntimeVersion> {
-		Ok(Substrate::<C, _, _>::runtime_version(&self.client).await?)
+		Ok(Substrate::<C>::runtime_version(&self.client).await?)
 	}
 
 	/// Return native tokens balance of the account.
@@ -171,7 +171,7 @@ impl<C: Chain> Client<C> {
 		C: ChainWithBalances,
 	{
 		let storage_key = C::account_info_storage_key(&account);
-		let encoded_account_data = Substrate::<C, _, _>::get_storage(&self.client, storage_key)
+		let encoded_account_data = Substrate::<C>::get_storage(&self.client, storage_key)
 			.await?
 			.ok_or(Error::AccountDoesNotExist)?;
 		let decoded_account_data =
@@ -184,14 +184,14 @@ impl<C: Chain> Client<C> {
 	///
 	/// 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?)
+		Ok(Substrate::<C>::system_account_next_index(&self.client, account).await?)
 	}
 
 	/// Submit an extrinsic for inclusion in a block.
 	///
 	/// Note: The given transaction does not need be SCALE encoded beforehand.
 	pub async fn submit_extrinsic(&self, transaction: Bytes) -> Result<C::Hash> {
-		let tx_hash = Substrate::<C, _, _>::author_submit_extrinsic(&self.client, transaction).await?;
+		let tx_hash = Substrate::<C>::author_submit_extrinsic(&self.client, transaction).await?;
 		log::trace!(target: "bridge", "Sent transaction to Substrate node: {:?}", tx_hash);
 		Ok(tx_hash)
 	}
@@ -201,7 +201,7 @@ impl<C: Chain> Client<C> {
 		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(&self.client, call, data, Some(block)).await?;
 		let authority_list = encoded_response.0;
 
 		Ok(authority_list)
@@ -209,7 +209,7 @@ impl<C: Chain> Client<C> {
 
 	/// 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)
+		Substrate::<C>::state_call(&self.client, method, data, at_block)
 			.await
 			.map_err(Into::into)
 	}
@@ -223,7 +223,7 @@ impl<C: Chain> Client<C> {
 		include_outbound_lane_state: bool,
 		at_block: C::Hash,
 	) -> Result<StorageProof> {
-		let encoded_trie_nodes = SubstrateMessageLane::<C, _, _>::prove_messages(
+		let encoded_trie_nodes = SubstrateMessageLane::<C>::prove_messages(
 			&self.client,
 			instance,
 			lane,
@@ -233,7 +233,7 @@ impl<C: Chain> Client<C> {
 			Some(at_block),
 		)
 		.await
-		.map_err(Error::Request)?;
+		.map_err(Error::RpcError)?;
 		let decoded_trie_nodes: Vec<Vec<u8>> =
 			Decode::decode(&mut &encoded_trie_nodes[..]).map_err(Error::ResponseParseFailed)?;
 		Ok(StorageProof::new(decoded_trie_nodes))
@@ -247,21 +247,21 @@ impl<C: Chain> Client<C> {
 		at_block: C::Hash,
 	) -> Result<Vec<Vec<u8>>> {
 		let encoded_trie_nodes =
-			SubstrateMessageLane::<C, _, _>::prove_messages_delivery(&self.client, instance, lane, Some(at_block))
+			SubstrateMessageLane::<C>::prove_messages_delivery(&self.client, instance, lane, Some(at_block))
 				.await
-				.map_err(Error::Request)?;
+				.map_err(Error::RpcError)?;
 		let decoded_trie_nodes: Vec<Vec<u8>> =
 			Decode::decode(&mut &encoded_trie_nodes[..]).map_err(Error::ResponseParseFailed)?;
 		Ok(decoded_trie_nodes)
 	}
 
 	/// Return new justifications stream.
-	pub async fn subscribe_justifications(self) -> Result<JustificationsSubscription> {
+	pub async fn subscribe_justifications(&self) -> Result<JustificationsSubscription> {
 		Ok(self
 			.client
 			.subscribe(
 				"grandpa_subscribeJustifications",
-				jsonrpsee::common::Params::None,
+				jsonrpsee_types::jsonrpc::Params::None,
 				"grandpa_unsubscribeJustifications",
 			)
 			.await?)

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

@@ -16,8 +16,7 @@
 
 //! Substrate node RPC errors.
 
-use jsonrpsee::client::RequestError;
-use jsonrpsee::transport::ws::WsNewDnsError;
+use jsonrpsee_types::error::Error as RpcError;
 use relay_utils::MaybeConnectionError;
 use sc_rpc_api::system::Health;
 
@@ -28,11 +27,9 @@ pub type Result<T> = std::result::Result<T, Error>;
 /// a Substrate node through RPC.
 #[derive(Debug)]
 pub enum Error {
-	/// Web socket connection error.
-	WsConnectionError(WsNewDnsError),
 	/// An error that can occur when making a request to
 	/// an JSON-RPC server.
-	Request(RequestError),
+	RpcError(RpcError),
 	/// The response from the server could not be SCALE decoded.
 	ResponseParseFailed(codec::Error),
 	/// The Substrate bridge pallet has not yet been initialized.
@@ -45,15 +42,9 @@ pub enum Error {
 	Custom(String),
 }
 
-impl From<WsNewDnsError> for Error {
-	fn from(error: WsNewDnsError) -> Self {
-		Error::WsConnectionError(error)
-	}
-}
-
-impl From<RequestError> for Error {
-	fn from(error: RequestError) -> Self {
-		Error::Request(error)
+impl From<RpcError> for Error {
+	fn from(error: RpcError) -> Self {
+		Error::RpcError(error)
 	}
 }
 
@@ -61,7 +52,11 @@ impl MaybeConnectionError for Error {
 	fn is_connection_error(&self) -> bool {
 		matches!(
 			*self,
-			Error::Request(RequestError::TransportError(_)) | Error::ClientNotSynced(_)
+			Error::RpcError(RpcError::TransportError(_))
+				// right now if connection to the ws server is dropped (after it is already established),
+				// we're getting this error
+				| Error::RpcError(RpcError::Internal(_))
+				| Error::ClientNotSynced(_),
 		)
 	}
 }
@@ -75,8 +70,7 @@ impl From<Error> for String {
 impl ToString for Error {
 	fn to_string(&self) -> String {
 		match self {
-			Self::WsConnectionError(e) => e.to_string(),
-			Self::Request(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(),
 			Self::AccountDoesNotExist => "Account does not exist on the chain".into(),

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

@@ -32,7 +32,7 @@ use sp_core::{
 };
 use sp_version::RuntimeVersion;
 
-jsonrpsee::rpc_api! {
+jsonrpsee_proc_macros::rpc_client_api! {
 	pub(crate) Substrate<C: Chain> {
 		#[rpc(method = "system_health", positional_params)]
 		fn system_health() -> Health;

bridges/relays/substrate/src/headers_maintain.rs

@@ -47,8 +47,10 @@ use sp_runtime::{traits::Header as HeaderT, Justification};
 use std::{collections::VecDeque, marker::PhantomData, task::Poll};
 
 /// Substrate-to-Substrate headers synchronization maintain procedure.
-pub struct SubstrateHeadersToSubstrateMaintain<P: SubstrateHeadersSyncPipeline, SourceChain, TargetChain: Chain> {
+pub struct SubstrateHeadersToSubstrateMaintain<P: SubstrateHeadersSyncPipeline, SourceChain: Chain, TargetChain: Chain>
+{
 	pipeline: P,
+	source_client: Client<SourceChain>,
 	target_client: Client<TargetChain>,
 	justifications: Arc<Mutex<Justifications<P>>>,
 	_marker: PhantomData<SourceChain>,
@@ -56,20 +58,23 @@ pub struct SubstrateHeadersToSubstrateMaintain<P: SubstrateHeadersSyncPipeline,
 
 /// Future and already received justifications from the source chain.
 struct Justifications<P: SubstrateHeadersSyncPipeline> {
-	/// Justifications stream.
-	stream: JustificationsSubscription,
+	/// Justifications stream. None if it hasn't been initialized yet, or it has been dropped
+	/// by the rpc library.
+	stream: Option<JustificationsSubscription>,
 	/// Justifications that we have read from the stream but have not sent to the
 	/// target node, because their targets were still not synced.
 	queue: VecDeque<(HeaderIdOf<P>, Justification)>,
 }
 
-impl<P: SubstrateHeadersSyncPipeline, SourceChain, TargetChain: Chain>
+impl<P: SubstrateHeadersSyncPipeline, SourceChain: Chain, TargetChain: Chain>
 	SubstrateHeadersToSubstrateMaintain<P, SourceChain, TargetChain>
 {
 	/// Create new maintain procedure.
-	pub fn new(pipeline: P, target_client: Client<TargetChain>, justifications: JustificationsSubscription) -> Self {
+	pub async fn new(pipeline: P, source_client: Client<SourceChain>, target_client: Client<TargetChain>) -> Self {
+		let justifications = subscribe_justifications(&source_client).await;
 		SubstrateHeadersToSubstrateMaintain {
 			pipeline,
+			source_client,
 			target_client,
 			justifications: Arc::new(Mutex::new(Justifications {
 				stream: justifications,
@@ -81,12 +86,13 @@ impl<P: SubstrateHeadersSyncPipeline, SourceChain, TargetChain: Chain>
 }
 
 #[async_trait]
-impl<P: SubstrateHeadersSyncPipeline, SourceChain, TargetChain: Chain> Clone
+impl<P: SubstrateHeadersSyncPipeline, SourceChain: Chain, TargetChain: Chain> Clone
 	for SubstrateHeadersToSubstrateMaintain<P, SourceChain, TargetChain>
 {
 	fn clone(&self) -> Self {
 		SubstrateHeadersToSubstrateMaintain {
 			pipeline: self.pipeline.clone(),
+			source_client: self.source_client.clone(),
 			target_client: self.target_client.clone(),
 			justifications: self.justifications.clone(),
 			_marker: Default::default(),
@@ -141,18 +147,23 @@ where
 
 		// Select justification to submit to the target node. We're submitting at most one justification
 		// on every maintain call. So maintain rate directly affects finalization rate.
-		let justification_to_submit = poll_fn(|context| {
+		let (resubscribe, justification_to_submit) = poll_fn(|context| {
 			// read justifications from the stream and push to the queue
-			justifications.read_from_stream::<SourceChain::Header>(context);
+			let resubscribe = !justifications.read_from_stream::<SourceChain::Header>(context);
 
 			// remove all obsolete justifications from the queue
 			remove_obsolete::<P>(&mut justifications.queue, best_finalized);
 
 			// select justification to submit
-			Poll::Ready(select_justification(&mut justifications.queue, sync))
+			Poll::Ready((resubscribe, select_justification(&mut justifications.queue, sync)))
 		})
 		.await;
 
+		// if justifications subscription has been dropped, resubscribe
+		if resubscribe {
+			justifications.stream = subscribe_justifications(&self.source_client).await;
+		}
+
 		// finally - submit selected justification
 		if let Some((target, justification)) = justification_to_submit {
 			let submit_result = self
@@ -187,20 +198,42 @@ where
 	P: SubstrateHeadersSyncPipeline<Completion = Justification, Extra = ()>,
 {
 	/// Read justifications from the subscription stream without blocking.
-	fn read_from_stream<'a, SourceHeader>(&mut self, context: &mut std::task::Context<'a>)
+	///
+	/// Returns `true` if justifications stream is still readable and `false` if it has been
+	/// dropped by the RPC crate && we need to resubscribe.
+	#[must_use]
+	fn read_from_stream<'a, SourceHeader>(&mut self, context: &mut std::task::Context<'a>) -> bool
 	where
 		SourceHeader: HeaderT,
 		SourceHeader::Number: Into<P::Number>,
 		SourceHeader::Hash: Into<P::Hash>,
 	{
+		let stream = match self.stream.as_mut() {
+			Some(stream) => stream,
+			None => return false,
+		};
+
 		loop {
-			let maybe_next_justification = self.stream.next();
+			let maybe_next_justification = stream.next();
 			futures::pin_mut!(maybe_next_justification);
 
 			let maybe_next_justification = maybe_next_justification.poll_unpin(context);
 			let justification = match maybe_next_justification {
 				Poll::Ready(justification) => justification,
-				Poll::Pending => return,
+				Poll::Pending => return true,
+			};
+
+			let justification = match justification {
+				Some(justification) => justification,
+				None => {
+					log::warn!(
+						target: "bridge",
+						"{} justifications stream has been dropped. Will be trying to resubscribe",
+						P::SOURCE_NAME,
+					);
+
+					return false;
+				}
 			};
 
 			// decode justification target
@@ -302,6 +335,31 @@ where
 	Ok(best_header_id)
 }
 
+/// Subscribe to justifications stream at source node.
+async fn subscribe_justifications<C: Chain>(client: &Client<C>) -> Option<JustificationsSubscription> {
+	match client.subscribe_justifications().await {
+		Ok(source_justifications) => {
+			log::debug!(
+				target: "bridge",
+				"Successfully (re)subscribed to {} justifications",
+				C::NAME,
+			);
+
+			Some(source_justifications)
+		}
+		Err(error) => {
+			log::warn!(
+				target: "bridge",
+				"Failed to subscribe to {} justifications: {:?}",
+				C::NAME,
+				error,
+			);
+
+			None
+		}
+	}
+}
+
 #[cfg(test)]
 mod tests {
 	use super::*;

bridges/relays/substrate/src/headers_pipeline.rs

@@ -139,25 +139,12 @@ pub async fn run<SourceChain, TargetChain, P>(
 	BlockNumberOf<SourceChain>: BlockNumberBase,
 	TargetChain: Clone + Chain,
 {
-	let source_justifications = match source_client.clone().subscribe_justifications().await {
-		Ok(source_justifications) => source_justifications,
-		Err(error) => {
-			log::warn!(
-				target: "bridge",
-				"Failed to subscribe to {} justifications: {:?}",
-				SourceChain::NAME,
-				error,
-			);
-
-			return;
-		}
-	};
-
 	let sync_maintain = SubstrateHeadersToSubstrateMaintain::<_, SourceChain, _>::new(
 		pipeline.clone(),
+		source_client.clone(),
 		target_client.clone(),
-		source_justifications,
-	);
+	)
+	.await;
 
 	log::info!(
 		target: "bridge",