Allow Multiple Bridge Pallet Instances (#226)

* Add Instance type parameter to pallet

* Sketch out what the runtime could look like

* Allow runtime to compile with multiple bridge pallets

* Cargo Fmt

* Allow an instance of a PoA chain to be used with currency-exchange

I specify that it's only _an instance_ instead of _instances_ since the currency-exchange
pallet does not support multiple instances itself. What this commit does is make it so
that the different instances of the PoA chains we currently have are compatible with the
currency-exchange pallet through the implementation of the PeerBlockchain trait.

* Add Instance type parameter to Currency Exchange pallet

* Wire up currency exchange intances in runtime

* Rust Fmt

* Show sccache

* Allow Eth pallet to use a default instance

* Use a default instance in Eth pallet tests

* Remove Rialto and Kovan feature flags

Through some discussions it has been decided that the `bridge-node` should, like
Substrate's `node-template`, be a showcase of the different pallets available in
a project. Because of this I've removed the feature flags for the Rialto and Kovan
networks in favour of having both of them included in the runtime.

* Update the chain_spec to use both Rialto and Kovan configs

* Update pallet level calls used by Substrate client

Allows the project to compile. However, it should be noted that in reality
we shouldn't be hardcoding the pallet we're calling.

* Allow currency-exchange pallet to use a default instance

* Support benchmarking an instance of the Eth pallet

* Update currency exchange benchmarks to work with instances

* Fix test helpers which now need a PoA instance

* Remove Actions for checking Rialto and Kovan features

* Add missing comments

* Update Runtime API string constants

* Add issue number for generic chain support in relay

* Add Runtime APIs for instances of the currency-exchange pallet

* Rust Fmt

Co-authored-by: Denis S. Soldatov aka General-Beck <general.beck@gmail.com>

bridges/bin/node/node/Cargo.toml

@@ -146,9 +146,7 @@ tag = 'v2.0.0-rc4'
 git = "https://github.com/paritytech/substrate.git"
 
 [features]
-default = ["bridge-rialto"]
-bridge-kovan = ["bridge-node-runtime/bridge-kovan"]
-bridge-rialto = ["bridge-node-runtime/bridge-rialto"]
+default = []
 runtime-benchmarks = [
 	"bridge-node-runtime/runtime-benchmarks",
 ]

bridges/bin/node/node/src/chain_spec.rs

@@ -15,8 +15,8 @@
 // along with Parity Bridges Common.  If not, see <http://www.gnu.org/licenses/>.
 
 use bridge_node_runtime::{
-	AccountId, AuraConfig, BalancesConfig, BridgeEthPoAConfig, GenesisConfig, GrandpaConfig, SessionConfig,
-	SessionKeys, Signature, SudoConfig, SystemConfig, WASM_BINARY,
+	AccountId, AuraConfig, BalancesConfig, BridgeKovanConfig, BridgeRialtoConfig, GenesisConfig, GrandpaConfig,
+	SessionConfig, SessionKeys, Signature, SudoConfig, SystemConfig, WASM_BINARY,
 };
 use grandpa_primitives::AuthorityId as GrandpaId;
 use sp_consensus_aura::sr25519::AuthorityId as AuraId;
@@ -152,7 +152,8 @@ fn testnet_genesis(
 		pallet_aura: Some(AuraConfig {
 			authorities: Vec::new(),
 		}),
-		pallet_bridge_eth_poa: load_bridge_config(),
+		pallet_bridge_eth_poa_Instance1: load_rialto_bridge_config(),
+		pallet_bridge_eth_poa_Instance2: load_kovan_bridge_config(),
 		pallet_grandpa: Some(GrandpaConfig {
 			authorities: Vec::new(),
 		}),
@@ -166,10 +167,18 @@ fn testnet_genesis(
 	}
 }
 
-fn load_bridge_config() -> Option<BridgeEthPoAConfig> {
-	Some(BridgeEthPoAConfig {
-		initial_header: bridge_node_runtime::bridge::genesis_header(),
+fn load_rialto_bridge_config() -> Option<BridgeRialtoConfig> {
+	Some(BridgeRialtoConfig {
+		initial_header: bridge_node_runtime::rialto::genesis_header(),
 		initial_difficulty: 0.into(),
-		initial_validators: bridge_node_runtime::bridge::genesis_validators(),
+		initial_validators: bridge_node_runtime::rialto::genesis_validators(),
+	})
+}
+
+fn load_kovan_bridge_config() -> Option<BridgeKovanConfig> {
+	Some(BridgeKovanConfig {
+		initial_header: bridge_node_runtime::kovan::genesis_header(),
+		initial_difficulty: 0.into(),
+		initial_validators: bridge_node_runtime::kovan::genesis_validators(),
 	})
 }

bridges/bin/node/runtime/Cargo.toml

@@ -224,9 +224,7 @@ package = "substrate-wasm-builder-runner"
 git = "https://github.com/paritytech/substrate/"
 
 [features]
-default = ["std", "bridge-rialto"]
-bridge-kovan = []
-bridge-rialto = []
+default = ["std"]
 std = [
 	"pallet-aura/std",
 	"pallet-balances/std",
@@ -268,5 +266,4 @@ runtime-benchmarks = [
 	"pallet-bridge-eth-poa/runtime-benchmarks",
 	"sp-bridge-eth-poa/test-helpers",
 	"sp-runtime/runtime-benchmarks",
-	"bridge-kovan",
 ]

bridges/bin/node/runtime/src/exchange.rs

@@ -30,7 +30,6 @@
 use codec::{Decode, Encode};
 use frame_support::RuntimeDebug;
 use hex_literal::hex;
-use pallet_bridge_currency_exchange::Blockchain;
 use sp_bridge_eth_poa::{transaction_decode, RawTransaction};
 use sp_currency_exchange::{
 	Error as ExchangeError, LockFundsTransaction, MaybeLockFundsTransaction, Result as ExchangeResult,
@@ -65,25 +64,6 @@ pub struct EthereumTransactionTag {
 	pub nonce: sp_core::U256,
 }
 
-/// Eth blockchain from runtime perspective.
-pub struct EthBlockchain;
-
-impl Blockchain for EthBlockchain {
-	type Transaction = RawTransaction;
-	type TransactionInclusionProof = EthereumTransactionInclusionProof;
-
-	fn verify_transaction_inclusion_proof(proof: &Self::TransactionInclusionProof) -> Option<Self::Transaction> {
-		let is_transaction_finalized =
-			crate::BridgeEthPoA::verify_transaction_finalized(proof.block, proof.index, &proof.proof);
-
-		if !is_transaction_finalized {
-			return None;
-		}
-
-		proof.proof.get(proof.index as usize).cloned()
-	}
-}
-
 /// Eth transaction from runtime perspective.
 pub struct EthTransaction;
 
@@ -147,7 +127,7 @@ impl MaybeLockFundsTransaction for EthTransaction {
 
 /// Prepares everything required to bench claim of funds locked by given transaction.
 #[cfg(feature = "runtime-benchmarks")]
-pub(crate) fn prepare_environment_for_claim<T: pallet_bridge_eth_poa::Trait>(
+pub(crate) fn prepare_environment_for_claim<T: pallet_bridge_eth_poa::Trait<I>, I: pallet_bridge_eth_poa::Instance>(
 	transactions: &[RawTransaction],
 ) -> sp_bridge_eth_poa::H256 {
 	use pallet_bridge_eth_poa::{
@@ -156,8 +136,8 @@ pub(crate) fn prepare_environment_for_claim<T: pallet_bridge_eth_poa::Trait>(
 	};
 	use sp_bridge_eth_poa::compute_merkle_root;
 
-	let mut storage = BridgeStorage::<T>::new();
-	let header = HeaderBuilder::with_parent_number_on_runtime::<T>(0)
+	let mut storage = BridgeStorage::<T, I>::new();
+	let header = HeaderBuilder::with_parent_number_on_runtime::<T, I>(0)
 		.with_transactions_root(compute_merkle_root(transactions.iter()))
 		.sign_by(&validator(0));
 	let header_id = header.compute_id();

bridges/bin/node/runtime/src/kovan.rs

@@ -14,12 +14,15 @@
 // You should have received a copy of the GNU General Public License
 // along with Parity Bridges Common.  If not, see <http://www.gnu.org/licenses/>.
 
+use crate::exchange::EthereumTransactionInclusionProof;
+
 use frame_support::RuntimeDebug;
 use hex_literal::hex;
+use pallet_bridge_currency_exchange::PeerBlockchain;
 use pallet_bridge_eth_poa::{
 	AuraConfiguration, PruningStrategy as BridgePruningStrategy, ValidatorsConfiguration, ValidatorsSource,
 };
-use sp_bridge_eth_poa::{Address, Header, U256};
+use sp_bridge_eth_poa::{Address, Header, RawTransaction, U256};
 use sp_std::prelude::*;
 
 frame_support::parameter_types! {
@@ -131,6 +134,25 @@ impl BridgePruningStrategy for PruningStrategy {
 	}
 }
 
+/// The Kovan Blockchain as seen by the runtime.
+pub struct KovanBlockchain;
+
+impl PeerBlockchain for KovanBlockchain {
+	type Transaction = RawTransaction;
+	type TransactionInclusionProof = EthereumTransactionInclusionProof;
+
+	fn verify_transaction_inclusion_proof(proof: &Self::TransactionInclusionProof) -> Option<Self::Transaction> {
+		let is_transaction_finalized =
+			crate::BridgeKovan::verify_transaction_finalized(proof.block, proof.index, &proof.proof);
+
+		if !is_transaction_finalized {
+			return None;
+		}
+
+		proof.proof.get(proof.index as usize).cloned()
+	}
+}
+
 #[cfg(test)]
 mod tests {
 	use super::*;

bridges/bin/node/runtime/src/lib.rs

@@ -32,17 +32,11 @@ pub mod exchange;
 
 #[cfg(feature = "runtime-benchmarks")]
 pub mod benches;
-#[cfg(feature = "bridge-kovan")]
 pub mod kovan;
-#[cfg(feature = "bridge-rialto")]
 pub mod rialto;
 
 #[cfg(feature = "runtime-benchmarks")]
 pub use benches as bridge;
-#[cfg(all(feature = "bridge-kovan", not(feature = "runtime-benchmarks")))]
-pub use kovan as bridge;
-#[cfg(all(feature = "bridge-rialto", not(feature = "runtime-benchmarks")))]
-pub use rialto as bridge;
 
 use codec::{Decode, Encode};
 use pallet_grandpa::{fg_primitives, AuthorityId as GrandpaId, AuthorityList as GrandpaAuthorityList};
@@ -69,10 +63,12 @@ pub use frame_support::{
 	weights::{IdentityFee, RuntimeDbWeight, Weight},
 	StorageValue,
 };
+
 pub use pallet_balances::Call as BalancesCall;
 pub use pallet_bridge_currency_exchange::Call as BridgeCurrencyExchangeCall;
 pub use pallet_bridge_eth_poa::Call as BridgeEthPoACall;
 pub use pallet_timestamp::Call as TimestampCall;
+
 #[cfg(any(feature = "std", test))]
 pub use sp_runtime::BuildStorage;
 pub use sp_runtime::{Perbill, Permill};
@@ -233,17 +229,39 @@ impl pallet_aura::Trait for Runtime {
 	type AuthorityId = AuraId;
 }
 
-impl pallet_bridge_eth_poa::Trait for Runtime {
-	type AuraConfiguration = bridge::BridgeAuraConfiguration;
-	type FinalityVotesCachingInterval = bridge::FinalityVotesCachingInterval;
-	type ValidatorsConfiguration = bridge::BridgeValidatorsConfiguration;
-	type PruningStrategy = bridge::PruningStrategy;
+type Rialto = pallet_bridge_eth_poa::Instance1;
+impl pallet_bridge_eth_poa::Trait<Rialto> for Runtime {
+	type AuraConfiguration = rialto::BridgeAuraConfiguration;
+	type FinalityVotesCachingInterval = rialto::FinalityVotesCachingInterval;
+	type ValidatorsConfiguration = rialto::BridgeValidatorsConfiguration;
+	type PruningStrategy = rialto::PruningStrategy;
 	type OnHeadersSubmitted = ();
 }
 
-impl pallet_bridge_currency_exchange::Trait for Runtime {
+type Kovan = pallet_bridge_eth_poa::Instance2;
+impl pallet_bridge_eth_poa::Trait<Kovan> for Runtime {
+	type AuraConfiguration = kovan::BridgeAuraConfiguration;
+	type FinalityVotesCachingInterval = kovan::FinalityVotesCachingInterval;
+	type ValidatorsConfiguration = kovan::BridgeValidatorsConfiguration;
+	type PruningStrategy = kovan::PruningStrategy;
+	type OnHeadersSubmitted = ();
+}
+
+type RialtoCurrencyExchange = pallet_bridge_currency_exchange::Instance1;
+impl pallet_bridge_currency_exchange::Trait<RialtoCurrencyExchange> for Runtime {
 	type OnTransactionSubmitted = ();
-	type PeerBlockchain = exchange::EthBlockchain;
+	type PeerBlockchain = rialto::RialtoBlockchain;
+	type PeerMaybeLockFundsTransaction = exchange::EthTransaction;
+	type RecipientsMap = sp_currency_exchange::IdentityRecipients<AccountId>;
+	type Amount = Balance;
+	type CurrencyConverter = sp_currency_exchange::IdentityCurrencyConverter<Balance>;
+	type DepositInto = DepositInto;
+}
+
+type KovanCurrencyExchange = pallet_bridge_currency_exchange::Instance2;
+impl pallet_bridge_currency_exchange::Trait<KovanCurrencyExchange> for Runtime {
+	type OnTransactionSubmitted = ();
+	type PeerBlockchain = kovan::KovanBlockchain;
 	type PeerMaybeLockFundsTransaction = exchange::EthTransaction;
 	type RecipientsMap = sp_currency_exchange::IdentityRecipients<AccountId>;
 	type Amount = Balance;
@@ -439,6 +457,10 @@ construct_runtime!(
 		NodeBlock = opaque::Block,
 		UncheckedExtrinsic = UncheckedExtrinsic
 	{
+		BridgeRialto: pallet_bridge_eth_poa::<Instance1>::{Module, Call, Config, Storage, ValidateUnsigned},
+		BridgeKovan: pallet_bridge_eth_poa::<Instance2>::{Module, Call, Config, Storage, ValidateUnsigned},
+		BridgeRialtoCurrencyExchange: pallet_bridge_currency_exchange::<Instance1>::{Module, Call},
+		BridgeKovanCurrencyExchange: pallet_bridge_currency_exchange::<Instance2>::{Module, Call},
 		System: frame_system::{Module, Call, Config, Storage, Event<T>},
 		RandomnessCollectiveFlip: pallet_randomness_collective_flip::{Module, Call, Storage},
 		Timestamp: pallet_timestamp::{Module, Call, Storage, Inherent},
@@ -448,8 +470,6 @@ construct_runtime!(
 		TransactionPayment: pallet_transaction_payment::{Module, Storage},
 		Sudo: pallet_sudo::{Module, Call, Config<T>, Storage, Event<T>},
 		Session: pallet_session::{Module, Call, Storage, Event, Config<T>},
-		BridgeEthPoA: pallet_bridge_eth_poa::{Module, Call, Config, Storage, ValidateUnsigned},
-		BridgeCurrencyExchange: pallet_bridge_currency_exchange::{Module, Call},
 	}
 );
 
@@ -535,32 +555,59 @@ impl_runtime_apis! {
 		}
 	}
 
-	impl sp_bridge_eth_poa::EthereumHeadersApi<Block> for Runtime {
+	impl sp_bridge_eth_poa::RialtoHeaderApi<Block> for Runtime {
 		fn best_block() -> (u64, sp_bridge_eth_poa::H256) {
-			let best_block = BridgeEthPoA::best_block();
+			let best_block = BridgeRialto::best_block();
 			(best_block.number, best_block.hash)
 		}
 
 		fn finalized_block() -> (u64, sp_bridge_eth_poa::H256) {
-			let finalized_block = BridgeEthPoA::finalized_block();
+			let finalized_block = BridgeRialto::finalized_block();
 			(finalized_block.number, finalized_block.hash)
 		}
 
 		fn is_import_requires_receipts(header: sp_bridge_eth_poa::Header) -> bool {
-			BridgeEthPoA::is_import_requires_receipts(header)
+			BridgeRialto::is_import_requires_receipts(header)
 		}
 
 		fn is_known_block(hash: sp_bridge_eth_poa::H256) -> bool {
-			BridgeEthPoA::is_known_block(hash)
+			BridgeRialto::is_known_block(hash)
 		}
 	}
 
-	impl sp_currency_exchange::CurrencyExchangeApi<Block, exchange::EthereumTransactionInclusionProof> for Runtime {
-		fn filter_transaction_proof(proof: exchange::EthereumTransactionInclusionProof) -> bool {
-			BridgeCurrencyExchange::filter_transaction_proof(&proof)
+	impl sp_bridge_eth_poa::KovanHeaderApi<Block> for Runtime {
+		fn best_block() -> (u64, sp_bridge_eth_poa::H256) {
+			let best_block = BridgeKovan::best_block();
+			(best_block.number, best_block.hash)
+		}
+
+		fn finalized_block() -> (u64, sp_bridge_eth_poa::H256) {
+			let finalized_block = BridgeKovan::finalized_block();
+			(finalized_block.number, finalized_block.hash)
+		}
+
+		fn is_import_requires_receipts(header: sp_bridge_eth_poa::Header) -> bool {
+			BridgeKovan::is_import_requires_receipts(header)
+		}
+
+		fn is_known_block(hash: sp_bridge_eth_poa::H256) -> bool {
+			BridgeKovan::is_known_block(hash)
 		}
 	}
 
+	impl sp_currency_exchange::RialtoCurrencyExchangeApi<Block, exchange::EthereumTransactionInclusionProof> for Runtime {
+		fn filter_transaction_proof(proof: exchange::EthereumTransactionInclusionProof) -> bool {
+			BridgeRialtoCurrencyExchange::filter_transaction_proof(&proof)
+		}
+	}
+
+	impl sp_currency_exchange::KovanCurrencyExchangeApi<Block, exchange::EthereumTransactionInclusionProof> for Runtime {
+		fn filter_transaction_proof(proof: exchange::EthereumTransactionInclusionProof) -> bool {
+			BridgeKovanCurrencyExchange::filter_transaction_proof(&proof)
+		}
+	}
+
+
 	impl sp_transaction_pool::runtime_api::TaggedTransactionQueue<Block> for Runtime {
 		fn validate_transaction(
 			source: TransactionSource,
@@ -656,14 +703,14 @@ impl_runtime_apis! {
 				ProofParams as BridgeCurrencyExchangeProofParams,
 			};
 
-			impl BridgeCurrencyExchangeTrait for Runtime {
+			impl BridgeCurrencyExchangeTrait<KovanCurrencyExchange> for Runtime {
 				fn make_proof(
 					proof_params: BridgeCurrencyExchangeProofParams<AccountId>,
 				) -> crate::exchange::EthereumTransactionInclusionProof {
 					use sp_currency_exchange::DepositInto;
 
 					if proof_params.recipient_exists {
-						<Runtime as pallet_bridge_currency_exchange::Trait>::DepositInto::deposit_into(
+						<Runtime as pallet_bridge_currency_exchange::Trait<KovanCurrencyExchange>>::DepositInto::deposit_into(
 							proof_params.recipient.clone(),
 							ExistentialDeposit::get(),
 						).unwrap();
@@ -681,7 +728,7 @@ impl_runtime_apis! {
 					let transactions = sp_std::iter::repeat(transaction.clone())
 						.take(1 + proof_params.proof_size_factor as usize)
 						.collect::<Vec<_>>();
-					let block_hash = crate::exchange::prepare_environment_for_claim::<Runtime>(&transactions);
+					let block_hash = crate::exchange::prepare_environment_for_claim::<Runtime, Kovan>(&transactions);
 					crate::exchange::EthereumTransactionInclusionProof {
 						block: block_hash,
 						index: 0,
@@ -690,8 +737,8 @@ impl_runtime_apis! {
 				}
 			}
 
-			add_benchmark!(params, batches, b"bridge-eth-poa", BridgeEthPoA);
-			add_benchmark!(params, batches, b"bridge-currency-exchange", BridgeCurrencyExchangeBench::<Runtime>);
+			add_benchmark!(params, batches, b"bridge-eth-poa", BridgeKovan);
+			add_benchmark!(params, batches, b"bridge-currency-exchange", BridgeCurrencyExchangeBench::<Runtime, KovanCurrencyExchange>);
 
 			if batches.is_empty() { return Err("Benchmark not found for this pallet.".into()) }
 			Ok(batches)
@@ -785,7 +832,7 @@ mod tests {
 			let initial_amount =
 				<pallet_balances::Module<Runtime> as Currency<AccountId>>::free_balance(&existing_account);
 			let additional_amount = 10_000;
-			<Runtime as pallet_bridge_currency_exchange::Trait>::DepositInto::deposit_into(
+			<Runtime as pallet_bridge_currency_exchange::Trait<KovanCurrencyExchange>>::DepositInto::deposit_into(
 				existing_account.clone(),
 				additional_amount,
 			)
@@ -804,7 +851,7 @@ mod tests {
 			let initial_amount = 0;
 			let additional_amount = ExistentialDeposit::get() + 10_000;
 			let new_account: AccountId = [42u8; 32].into();
-			<Runtime as pallet_bridge_currency_exchange::Trait>::DepositInto::deposit_into(
+			<Runtime as pallet_bridge_currency_exchange::Trait<KovanCurrencyExchange>>::DepositInto::deposit_into(
 				new_account.clone(),
 				additional_amount,
 			)

bridges/bin/node/runtime/src/rialto.rs

@@ -14,12 +14,15 @@
 // You should have received a copy of the GNU General Public License
 // along with Parity Bridges Common.  If not, see <http://www.gnu.org/licenses/>.
 
+use crate::exchange::EthereumTransactionInclusionProof;
+
 use frame_support::RuntimeDebug;
 use hex_literal::hex;
+use pallet_bridge_currency_exchange::PeerBlockchain;
 use pallet_bridge_eth_poa::{
 	AuraConfiguration, PruningStrategy as TPruningStrategy, ValidatorsConfiguration, ValidatorsSource,
 };
-use sp_bridge_eth_poa::{Address, Header, U256};
+use sp_bridge_eth_poa::{Address, Header, RawTransaction, U256};
 use sp_std::prelude::*;
 
 frame_support::parameter_types! {
@@ -104,6 +107,25 @@ impl TPruningStrategy for PruningStrategy {
 	}
 }
 
+/// The Rialto Blockchain as seen by the runtime.
+pub struct RialtoBlockchain;
+
+impl PeerBlockchain for RialtoBlockchain {
+	type Transaction = RawTransaction;
+	type TransactionInclusionProof = EthereumTransactionInclusionProof;
+
+	fn verify_transaction_inclusion_proof(proof: &Self::TransactionInclusionProof) -> Option<Self::Transaction> {
+		let is_transaction_finalized =
+			crate::BridgeRialto::verify_transaction_finalized(proof.block, proof.index, &proof.proof);
+
+		if !is_transaction_finalized {
+			return None;
+		}
+
+		proof.proof.get(proof.index as usize).cloned()
+	}
+}
+
 #[cfg(test)]
 mod tests {
 	use super::*;

bridges/modules/currency-exchange/src/benchmarking.rs

@@ -18,10 +18,10 @@
 //! So we are giving runtime opportunity to prepare environment and construct proof
 //! before invoking module calls.
 
-use super::{Blockchain, Call, Module as CurrencyExchangeModule, Trait as CurrencyExchangeTrait};
+use super::{Call, Instance, Module as CurrencyExchangeModule, PeerBlockchain, Trait as CurrencyExchangeTrait};
 use sp_std::prelude::*;
 
-use frame_benchmarking::{account, benchmarks};
+use frame_benchmarking::{account, benchmarks_instance};
 use frame_system::RawOrigin;
 
 const SEED: u32 = 0;
@@ -29,7 +29,7 @@ const WORST_TX_SIZE_FACTOR: u32 = 1000;
 const WORST_PROOF_SIZE_FACTOR: u32 = 1000;
 
 /// Module we're benchmarking here.
-pub struct Module<T: Trait>(CurrencyExchangeModule<T>);
+pub struct Module<T: Trait<I>, I: Instance>(CurrencyExchangeModule<T, I>);
 
 /// Proof benchmarking parameters.
 pub struct ProofParams<Recipient> {
@@ -46,14 +46,14 @@ pub struct ProofParams<Recipient> {
 }
 
 /// Trait that must be implemented by runtime.
-pub trait Trait: CurrencyExchangeTrait {
+pub trait Trait<I: Instance>: CurrencyExchangeTrait<I> {
 	/// Prepare proof for importing exchange transaction.
 	fn make_proof(
 		proof_params: ProofParams<Self::AccountId>,
-	) -> <<Self as CurrencyExchangeTrait>::PeerBlockchain as Blockchain>::TransactionInclusionProof;
+	) -> <<Self as CurrencyExchangeTrait<I>>::PeerBlockchain as PeerBlockchain>::TransactionInclusionProof;
 }
 
-benchmarks! {
+benchmarks_instance! {
 	_ { }
 
 	// Benchmark `import_peer_transaction` extrinsic with the best possible conditions:

bridges/modules/currency-exchange/src/lib.rs

@@ -33,8 +33,8 @@ pub trait OnTransactionSubmitted<AccountId> {
 	fn on_valid_transaction_submitted(submitter: AccountId);
 }
 
-/// Peer blockhain interface.
-pub trait Blockchain {
+/// Peer blockchain interface.
+pub trait PeerBlockchain {
 	/// Transaction type.
 	type Transaction: Parameter;
 	/// Transaction inclusion proof type.
@@ -47,14 +47,14 @@ pub trait Blockchain {
 }
 
 /// The module configuration trait
-pub trait Trait: frame_system::Trait {
+pub trait Trait<I = DefaultInstance>: frame_system::Trait {
 	/// Handler for transaction submission result.
 	type OnTransactionSubmitted: OnTransactionSubmitted<Self::AccountId>;
-	/// Peer blockchain type.
-	type PeerBlockchain: Blockchain;
+	/// Represents the blockchain that we'll be exchanging currency with.
+	type PeerBlockchain: PeerBlockchain;
 	/// Peer blockchain transaction parser.
 	type PeerMaybeLockFundsTransaction: MaybeLockFundsTransaction<
-		Transaction = <Self::PeerBlockchain as Blockchain>::Transaction,
+		Transaction = <Self::PeerBlockchain as PeerBlockchain>::Transaction,
 	>;
 	/// Map between blockchains recipients.
 	type RecipientsMap: RecipientsMap<
@@ -73,7 +73,7 @@ pub trait Trait: frame_system::Trait {
 }
 
 decl_error! {
-	pub enum Error for Module<T: Trait> {
+	pub enum Error for Module<T: Trait<I>, I: Instance> {
 		/// Invalid peer blockchain transaction provided.
 		InvalidTransaction,
 		/// Peer transaction has invalid amount.
@@ -96,17 +96,17 @@ decl_error! {
 }
 
 decl_module! {
-	pub struct Module<T: Trait> for enum Call where origin: T::Origin {
+	pub struct Module<T: Trait<I>, I: Instance = DefaultInstance> for enum Call where origin: T::Origin {
 		/// Imports lock fund transaction of the peer blockchain.
 		#[weight = 0] // TODO: update me (https://github.com/paritytech/parity-bridges-common/issues/78)
 		pub fn import_peer_transaction(
 			origin,
-			proof: <<T as Trait>::PeerBlockchain as Blockchain>::TransactionInclusionProof,
+			proof: <<T as Trait<I>>::PeerBlockchain as PeerBlockchain>::TransactionInclusionProof,
 		) -> DispatchResult {
 			let submitter = frame_system::ensure_signed(origin)?;
 
 			// verify and parse transaction proof
-			let deposit = prepare_deposit_details::<T>(&proof)?;
+			let deposit = prepare_deposit_details::<T, I>(&proof)?;
 
 			// make sure to update the mapping if we deposit successfully to avoid double spending,
 			// i.e. whenever `deposit_into` is successful we MUST update `Transfers`.
@@ -117,9 +117,9 @@ decl_module! {
 				match deposit_result {
 					Ok(_) => (),
 					Err(ExchangeError::DepositPartiallyFailed) => (),
-					Err(error) => return Err(Error::<T>::from(error).into()),
+					Err(error) => return Err(Error::<T, I>::from(error).into()),
 				}
-				Transfers::<T>::insert(&deposit.transfer_id, ())
+				Transfers::<T, I>::insert(&deposit.transfer_id, ())
 			}
 
 			// reward submitter for providing valid message
@@ -137,17 +137,17 @@ decl_module! {
 }
 
 decl_storage! {
-	trait Store for Module<T: Trait> as Bridge {
+	trait Store for Module<T: Trait<I>, I: Instance = DefaultInstance> as Bridge {
 		/// All transfers that have already been claimed.
 		Transfers: map hasher(blake2_128_concat) <T::PeerMaybeLockFundsTransaction as MaybeLockFundsTransaction>::Id => ();
 	}
 }
 
-impl<T: Trait> Module<T> {
+impl<T: Trait<I>, I: Instance> Module<T, I> {
 	/// Returns true if currency exchange module is able to import given transaction proof in
 	/// its current state.
-	pub fn filter_transaction_proof(proof: &<T::PeerBlockchain as Blockchain>::TransactionInclusionProof) -> bool {
-		if prepare_deposit_details::<T>(proof).is_err() {
+	pub fn filter_transaction_proof(proof: &<T::PeerBlockchain as PeerBlockchain>::TransactionInclusionProof) -> bool {
+		if prepare_deposit_details::<T, I>(proof).is_err() {
 			return false;
 		}
 
@@ -155,7 +155,7 @@ impl<T: Trait> Module<T> {
 	}
 }
 
-impl<T: Trait> From<ExchangeError> for Error<T> {
+impl<T: Trait<I>, I: Instance> From<ExchangeError> for Error<T, I> {
 	fn from(error: ExchangeError) -> Self {
 		match error {
 			ExchangeError::InvalidTransaction => Error::InvalidTransaction,
@@ -174,7 +174,7 @@ impl<AccountId> OnTransactionSubmitted<AccountId> for () {
 }
 
 /// Exchange deposit details.
-struct DepositDetails<T: Trait> {
+struct DepositDetails<T: Trait<I>, I: Instance> {
 	/// Transfer id.
 	pub transfer_id: <T::PeerMaybeLockFundsTransaction as MaybeLockFundsTransaction>::Id,
 	/// Transfer recipient.
@@ -185,21 +185,25 @@ struct DepositDetails<T: Trait> {
 
 /// Verify and parse transaction proof, preparing everything required for importing
 /// this transaction proof.
-fn prepare_deposit_details<T: Trait>(
-	proof: &<<T as Trait>::PeerBlockchain as Blockchain>::TransactionInclusionProof,
-) -> Result<DepositDetails<T>, Error<T>> {
+fn prepare_deposit_details<T: Trait<I>, I: Instance>(
+	proof: &<<T as Trait<I>>::PeerBlockchain as PeerBlockchain>::TransactionInclusionProof,
+) -> Result<DepositDetails<T, I>, Error<T, I>> {
 	// ensure that transaction is included in finalized block that we know of
-	let transaction = <T as Trait>::PeerBlockchain::verify_transaction_inclusion_proof(proof)
-		.ok_or_else(|| Error::<T>::UnfinalizedTransaction)?;
+	let transaction = <T as Trait<I>>::PeerBlockchain::verify_transaction_inclusion_proof(proof)
+		.ok_or_else(|| Error::<T, I>::UnfinalizedTransaction)?;
 
 	// parse transaction
-	let transaction = <T as Trait>::PeerMaybeLockFundsTransaction::parse(&transaction).map_err(Error::<T>::from)?;
+	let transaction =
+		<T as Trait<I>>::PeerMaybeLockFundsTransaction::parse(&transaction).map_err(Error::<T, I>::from)?;
 	let transfer_id = transaction.id;
-	ensure!(!Transfers::<T>::contains_key(&transfer_id), Error::<T>::AlreadyClaimed);
+	ensure!(
+		!Transfers::<T, I>::contains_key(&transfer_id),
+		Error::<T, I>::AlreadyClaimed
+	);
 
 	// grant recipient
-	let recipient = T::RecipientsMap::map(transaction.recipient).map_err(Error::<T>::from)?;
-	let amount = T::CurrencyConverter::convert(transaction.amount).map_err(Error::<T>::from)?;
+	let recipient = T::RecipientsMap::map(transaction.recipient).map_err(Error::<T, I>::from)?;
+	let amount = T::CurrencyConverter::convert(transaction.amount).map_err(Error::<T, I>::from)?;
 
 	Ok(DepositDetails {
 		transfer_id,
@@ -235,13 +239,13 @@ mod tests {
 
 	impl OnTransactionSubmitted<AccountId> for DummyTransactionSubmissionHandler {
 		fn on_valid_transaction_submitted(submitter: AccountId) {
-			Transfers::<TestRuntime>::insert(submitter, ());
+			Transfers::<TestRuntime, DefaultInstance>::insert(submitter, ());
 		}
 	}
 
 	pub struct DummyBlockchain;
 
-	impl Blockchain for DummyBlockchain {
+	impl PeerBlockchain for DummyBlockchain {
 		type Transaction = RawTransaction;
 		type TransactionInclusionProof = (bool, RawTransaction);
 
@@ -386,7 +390,7 @@ mod tests {
 		new_test_ext().execute_with(|| {
 			assert_noop!(
 				Exchange::import_peer_transaction(Origin::signed(SUBMITTER), (false, transaction(0))),
-				Error::<TestRuntime>::UnfinalizedTransaction,
+				Error::<TestRuntime, DefaultInstance>::UnfinalizedTransaction,
 			);
 		});
 	}
@@ -399,7 +403,7 @@ mod tests {
 					Origin::signed(SUBMITTER),
 					(true, transaction(INVALID_TRANSACTION_ID)),
 				),
-				Error::<TestRuntime>::InvalidTransaction,
+				Error::<TestRuntime, DefaultInstance>::InvalidTransaction,
 			);
 		});
 	}
@@ -413,7 +417,7 @@ mod tests {
 					Origin::signed(SUBMITTER),
 					(true, transaction(ALREADY_CLAIMED_TRANSACTION_ID)),
 				),
-				Error::<TestRuntime>::AlreadyClaimed,
+				Error::<TestRuntime, DefaultInstance>::AlreadyClaimed,
 			);
 		});
 	}
@@ -425,7 +429,7 @@ mod tests {
 			transaction.recipient = UNKNOWN_RECIPIENT_ID;
 			assert_noop!(
 				Exchange::import_peer_transaction(Origin::signed(SUBMITTER), (true, transaction)),
-				Error::<TestRuntime>::FailedToMapRecipients,
+				Error::<TestRuntime, DefaultInstance>::FailedToMapRecipients,
 			);
 		});
 	}
@@ -437,7 +441,7 @@ mod tests {
 			transaction.amount = INVALID_AMOUNT;
 			assert_noop!(
 				Exchange::import_peer_transaction(Origin::signed(SUBMITTER), (true, transaction)),
-				Error::<TestRuntime>::FailedToConvertCurrency,
+				Error::<TestRuntime, DefaultInstance>::FailedToConvertCurrency,
 			);
 		});
 	}
@@ -449,7 +453,7 @@ mod tests {
 			transaction.amount = MAX_DEPOSIT_AMOUNT + 1;
 			assert_noop!(
 				Exchange::import_peer_transaction(Origin::signed(SUBMITTER), (true, transaction)),
-				Error::<TestRuntime>::DepositFailed,
+				Error::<TestRuntime, DefaultInstance>::DepositFailed,
 			);
 		});
 	}

bridges/modules/ethereum/src/benchmarking.rs

@@ -21,11 +21,11 @@ use crate::test_utils::{
 	HeaderBuilder,
 };
 
-use frame_benchmarking::benchmarks;
+use frame_benchmarking::benchmarks_instance;
 use frame_system::RawOrigin;
 use primitives::{compute_merkle_root, U256};
 
-benchmarks! {
+benchmarks_instance! {
 	_ { }
 
 	// Benchmark `import_unsigned_header` extrinsic with the best possible conditions:
@@ -37,7 +37,7 @@ benchmarks! {
 		let n in 1..1000;
 
 		let num_validators = 2;
-		let initial_header = initialize_bench::<T>(num_validators);
+		let initial_header = initialize_bench::<T, I>(num_validators);
 
 		// prepare header to be inserted
 		let header = build_custom_header(
@@ -50,7 +50,7 @@ benchmarks! {
 		);
 	}: import_unsigned_header(RawOrigin::None, header, None)
 	verify {
-		let storage = BridgeStorage::<T>::new();
+		let storage = BridgeStorage::<T, I>::new();
 		assert_eq!(storage.best_block().0.number, 1);
 		assert_eq!(storage.finalized_block().number, 0);
 	}
@@ -67,9 +67,9 @@ benchmarks! {
 		// finalization.
 		let n in 1..7;
 
-		let mut storage = BridgeStorage::<T>::new();
+		let mut storage = BridgeStorage::<T, I>::new();
 		let num_validators: u32 = 2;
-		let initial_header = initialize_bench::<T>(num_validators as usize);
+		let initial_header = initialize_bench::<T, I>(num_validators as usize);
 
 		// Since we only have two validators we need to make sure the number of blocks is even to
 		// make sure the right validator signs the final block
@@ -95,7 +95,7 @@ benchmarks! {
 		let header = HeaderBuilder::with_parent(&last_header).sign_by(&last_authority);
 	}: import_unsigned_header(RawOrigin::None, header, None)
 	verify {
-		let storage = BridgeStorage::<T>::new();
+		let storage = BridgeStorage::<T, I>::new();
 		assert_eq!(storage.best_block().0.number, (num_blocks + 1) as u64);
 		assert_eq!(storage.finalized_block().number, num_blocks as u64);
 	}
@@ -108,9 +108,9 @@ benchmarks! {
 		// finalization.
 		let n in 7..100;
 
-		let mut storage = BridgeStorage::<T>::new();
+		let mut storage = BridgeStorage::<T, I>::new();
 		let num_validators: u32 = 2;
-		let initial_header = initialize_bench::<T>(num_validators as usize);
+		let initial_header = initialize_bench::<T, I>(num_validators as usize);
 
 		// Since we only have two validators we need to make sure the number of blocks is even to
 		// make sure the right validator signs the final block
@@ -136,7 +136,7 @@ benchmarks! {
 		let header = HeaderBuilder::with_parent(&last_header).sign_by(&last_authority);
 	}: import_unsigned_header(RawOrigin::None, header, None)
 	verify {
-		let storage = BridgeStorage::<T>::new();
+		let storage = BridgeStorage::<T, I>::new();
 		assert_eq!(storage.best_block().0.number, (num_blocks + 1) as u64);
 		assert_eq!(storage.finalized_block().number, num_blocks as u64);
 	}
@@ -148,14 +148,14 @@ benchmarks! {
 	import_unsigned_pruning {
 		let n in 1..MAX_BLOCKS_TO_PRUNE_IN_SINGLE_IMPORT as u32;
 
-		let mut storage = BridgeStorage::<T>::new();
+		let mut storage = BridgeStorage::<T, I>::new();
 
 		let num_validators = 3;
-		let initial_header = initialize_bench::<T>(num_validators as usize);
+		let initial_header = initialize_bench::<T, I>(num_validators as usize);
 		let validators = validators(num_validators);
 
 		// Want to prune eligible blocks between [0, n)
-		BlocksToPrune::put(PruningRange {
+		BlocksToPrune::<I>::put(PruningRange {
 			oldest_unpruned_block: 0,
 			oldest_block_to_keep: n as u64,
 		});
@@ -171,11 +171,11 @@ benchmarks! {
 		let header = HeaderBuilder::with_parent(&parent).sign_by_set(&validators);
 	}: import_unsigned_header(RawOrigin::None, header, None)
 	verify {
-		let storage = BridgeStorage::<T>::new();
+		let storage = BridgeStorage::<T, I>::new();
 		let max_pruned: u64 = (n - 1) as _;
 		assert_eq!(storage.best_block().0.number, (n + 1) as u64);
-		assert!(HeadersByNumber::get(&0).is_none());
-		assert!(HeadersByNumber::get(&max_pruned).is_none());
+		assert!(HeadersByNumber::<I>::get(&0).is_none());
+		assert!(HeadersByNumber::<I>::get(&max_pruned).is_none());
 	}
 
 	// The goal of this bench is to import a block which contains a transaction receipt. The receipt
@@ -184,10 +184,10 @@ benchmarks! {
 	import_unsigned_with_receipts {
 		let n in 1..100;
 
-		let mut storage = BridgeStorage::<T>::new();
+		let mut storage = BridgeStorage::<T, I>::new();
 
 		let num_validators = 1;
-		let initial_header = initialize_bench::<T>(num_validators as usize);
+		let initial_header = initialize_bench::<T, I>(num_validators as usize);
 
 		let mut receipts = vec![];
 		for i in 1..=n {
@@ -213,18 +213,18 @@ benchmarks! {
 		);
 	}: import_unsigned_header(RawOrigin::None, header, Some(receipts))
 	verify {
-		let storage = BridgeStorage::<T>::new();
+		let storage = BridgeStorage::<T, I>::new();
 		assert_eq!(storage.best_block().0.number, 2);
 	}
 }
 
-fn initialize_bench<T: Trait>(num_validators: usize) -> Header {
+fn initialize_bench<T: Trait<I>, I: Instance>(num_validators: usize) -> Header {
 	// Initialize storage with some initial header
 	let initial_header = build_genesis_header(&validator(0));
 	let initial_difficulty = initial_header.difficulty;
 	let initial_validators = validators_addresses(num_validators as usize);
 
-	initialize_storage::<T>(&initial_header, initial_difficulty, &initial_validators);
+	initialize_storage::<T, I>(&initial_header, initial_difficulty, &initial_validators);
 
 	initial_header
 }

bridges/modules/ethereum/src/import.rs

@@ -169,6 +169,7 @@ mod tests {
 		validators_change_receipt, HeaderBuilder, KeepSomeHeadersBehindBest, TestRuntime, GAS_LIMIT,
 	};
 	use crate::validators::ValidatorsSource;
+	use crate::DefaultInstance;
 	use crate::{BlocksToPrune, BridgeStorage, Headers, PruningRange};
 	use frame_support::{StorageMap, StorageValue};
 	use secp256k1::SecretKey;
@@ -352,7 +353,7 @@ mod tests {
 				step += 3;
 			}
 			assert_eq!(
-				BlocksToPrune::get(),
+				BlocksToPrune::<DefaultInstance>::get(),
 				PruningRange {
 					oldest_unpruned_block: 11,
 					oldest_block_to_keep: 14,
@@ -378,7 +379,7 @@ mod tests {
 			.unwrap();
 			assert_eq!(finalized_blocks, expected_blocks);
 			assert_eq!(
-				BlocksToPrune::get(),
+				BlocksToPrune::<DefaultInstance>::get(),
 				PruningRange {
 					oldest_unpruned_block: 15,
 					oldest_block_to_keep: 15,

bridges/modules/ethereum/src/lib.rs

@@ -351,7 +351,7 @@ impl<AccountId> OnHeadersSubmitted<AccountId> for () {
 }
 
 /// The module configuration trait.
-pub trait Trait: frame_system::Trait {
+pub trait Trait<I = DefaultInstance>: frame_system::Trait {
 	/// Aura configuration.
 	type AuraConfiguration: Get<AuraConfiguration>;
 	/// Validators configuration.
@@ -372,14 +372,14 @@ pub trait Trait: frame_system::Trait {
 }
 
 decl_module! {
-	pub struct Module<T: Trait> for enum Call where origin: T::Origin {
+	pub struct Module<T: Trait<I>, I: Instance = DefaultInstance> for enum Call where origin: T::Origin {
 		/// Import single Aura header. Requires transaction to be **UNSIGNED**.
 		#[weight = 0] // TODO: update me (https://github.com/paritytech/parity-bridges-common/issues/78)
 		pub fn import_unsigned_header(origin, header: Header, receipts: Option<Vec<Receipt>>) {
 			frame_system::ensure_none(origin)?;
 
 			import::import_header(
-				&mut BridgeStorage::<T>::new(),
+				&mut BridgeStorage::<T, I>::new(),
 				&mut T::PruningStrategy::default(),
 				&T::AuraConfiguration::get(),
 				&T::ValidatorsConfiguration::get(),
@@ -400,7 +400,7 @@ decl_module! {
 			let submitter = frame_system::ensure_signed(origin)?;
 			let mut finalized_headers = BTreeMap::new();
 			let import_result = import::import_headers(
-				&mut BridgeStorage::<T>::new(),
+				&mut BridgeStorage::<T, I>::new(),
 				&mut T::PruningStrategy::default(),
 				&T::AuraConfiguration::get(),
 				&T::ValidatorsConfiguration::get(),
@@ -434,7 +434,7 @@ decl_module! {
 }
 
 decl_storage! {
-	trait Store for Module<T: Trait> as Bridge {
+	trait Store for Module<T: Trait<I>, I: Instance = DefaultInstance> as Bridge {
 		/// Best known block.
 		BestBlock: (HeaderId, U256);
 		/// Best finalized block.
@@ -473,7 +473,7 @@ decl_storage! {
 				"Initial validators set can't be empty",
 			);
 
-			initialize_storage::<T>(
+			initialize_storage::<T, I>(
 				&config.initial_header,
 				config.initial_difficulty,
 				&config.initial_validators,
@@ -482,43 +482,47 @@ decl_storage! {
 	}
 }
 
-impl<T: Trait> Module<T> {
+impl<T: Trait<I>, I: Instance> Module<T, I> {
 	/// Returns number and hash of the best block known to the bridge module.
 	/// The caller should only submit `import_header` transaction that makes
 	/// (or leads to making) other header the best one.
 	pub fn best_block() -> HeaderId {
-		BridgeStorage::<T>::new().best_block().0
+		BridgeStorage::<T, I>::new().best_block().0
 	}
 
 	/// Returns number and hash of the best finalized block known to the bridge module.
 	pub fn finalized_block() -> HeaderId {
-		BridgeStorage::<T>::new().finalized_block()
+		BridgeStorage::<T, I>::new().finalized_block()
 	}
 
 	/// Returns true if the import of given block requires transactions receipts.
 	pub fn is_import_requires_receipts(header: Header) -> bool {
-		import::header_import_requires_receipts(&BridgeStorage::<T>::new(), &T::ValidatorsConfiguration::get(), &header)
+		import::header_import_requires_receipts(
+			&BridgeStorage::<T, I>::new(),
+			&T::ValidatorsConfiguration::get(),
+			&header,
+		)
 	}
 
 	/// Returns true if header is known to the runtime.
 	pub fn is_known_block(hash: H256) -> bool {
-		BridgeStorage::<T>::new().header(&hash).is_some()
+		BridgeStorage::<T, I>::new().header(&hash).is_some()
 	}
 
 	/// Verify that transaction is included into given finalized block.
 	pub fn verify_transaction_finalized(block: H256, tx_index: u64, proof: &[RawTransaction]) -> bool {
-		crate::verify_transaction_finalized(&BridgeStorage::<T>::new(), block, tx_index, proof)
+		crate::verify_transaction_finalized(&BridgeStorage::<T, I>::new(), block, tx_index, proof)
 	}
 }
 
-impl<T: Trait> frame_support::unsigned::ValidateUnsigned for Module<T> {
-	type Call = Call<T>;
+impl<T: Trait<I>, I: Instance> frame_support::unsigned::ValidateUnsigned for Module<T, I> {
+	type Call = Call<T, I>;
 
 	fn validate_unsigned(_source: TransactionSource, call: &Self::Call) -> TransactionValidity {
 		match *call {
 			Self::Call::import_unsigned_header(ref header, ref receipts) => {
 				let accept_result = verification::accept_aura_header_into_pool(
-					&BridgeStorage::<T>::new(),
+					&BridgeStorage::<T, I>::new(),
 					&T::AuraConfiguration::get(),
 					&T::ValidatorsConfiguration::get(),
 					&pool_configuration(),
@@ -550,17 +554,17 @@ impl<T: Trait> frame_support::unsigned::ValidateUnsigned for Module<T> {
 
 /// Runtime bridge storage.
 #[derive(Default)]
-pub struct BridgeStorage<T>(sp_std::marker::PhantomData<T>);
+pub struct BridgeStorage<T, I = DefaultInstance>(sp_std::marker::PhantomData<(T, I)>);
 
-impl<T: Trait> BridgeStorage<T> {
+impl<T: Trait<I>, I: Instance> BridgeStorage<T, I> {
 	/// Create new BridgeStorage.
 	pub fn new() -> Self {
-		BridgeStorage(sp_std::marker::PhantomData::<T>::default())
+		BridgeStorage(sp_std::marker::PhantomData::<(T, I)>::default())
 	}
 
 	/// Prune old blocks.
 	fn prune_blocks(&self, mut max_blocks_to_prune: u64, finalized_number: u64, prune_end: u64) {
-		let pruning_range = BlocksToPrune::get();
+		let pruning_range = BlocksToPrune::<I>::get();
 		let mut new_pruning_range = pruning_range.clone();
 
 		// update oldest block we want to keep
@@ -579,7 +583,7 @@ impl<T: Trait> BridgeStorage<T> {
 			}
 
 			// read hashes of blocks with given number and try to prune these blocks
-			let blocks_at_number = HeadersByNumber::take(number);
+			let blocks_at_number = HeadersByNumber::<I>::take(number);
 			if let Some(mut blocks_at_number) = blocks_at_number {
 				self.prune_blocks_by_hashes(
 					&mut max_blocks_to_prune,
@@ -590,7 +594,7 @@ impl<T: Trait> BridgeStorage<T> {
 
 				// if we haven't pruned all blocks, remember unpruned
 				if !blocks_at_number.is_empty() {
-					HeadersByNumber::insert(number, blocks_at_number);
+					HeadersByNumber::<I>::insert(number, blocks_at_number);
 					break;
 				}
 			}
@@ -606,7 +610,7 @@ impl<T: Trait> BridgeStorage<T> {
 
 		// update pruning range in storage
 		if pruning_range != new_pruning_range {
-			BlocksToPrune::put(new_pruning_range);
+			BlocksToPrune::<I>::put(new_pruning_range);
 		}
 	}
 
@@ -619,13 +623,13 @@ impl<T: Trait> BridgeStorage<T> {
 		blocks_at_number: &mut Vec<H256>,
 	) {
 		// ensure that unfinalized headers we want to prune do not have scheduled changes
-		if number > finalized_number && blocks_at_number.iter().any(ScheduledChanges::contains_key) {
+		if number > finalized_number && blocks_at_number.iter().any(ScheduledChanges::<I>::contains_key) {
 			return;
 		}
 
 		// physically remove headers and (probably) obsolete validators sets
 		while let Some(hash) = blocks_at_number.pop() {
-			let header = Headers::<T>::take(&hash);
+			let header = Headers::<T, I>::take(&hash);
 			frame_support::debug::trace!(
 				target: "runtime",
 				"Pruning PoA header: ({}, {})",
@@ -633,10 +637,10 @@ impl<T: Trait> BridgeStorage<T> {
 				hash,
 			);
 
-			ScheduledChanges::remove(hash);
-			FinalityCache::<T>::remove(hash);
+			ScheduledChanges::<I>::remove(hash);
+			FinalityCache::<T, I>::remove(hash);
 			if let Some(header) = header {
-				ValidatorsSetsRc::mutate(header.next_validators_set_id, |rc| match *rc {
+				ValidatorsSetsRc::<I>::mutate(header.next_validators_set_id, |rc| match *rc {
 					Some(rc) if rc > 1 => Some(rc - 1),
 					_ => None,
 				});
@@ -651,19 +655,19 @@ impl<T: Trait> BridgeStorage<T> {
 	}
 }
 
-impl<T: Trait> Storage for BridgeStorage<T> {
+impl<T: Trait<I>, I: Instance> Storage for BridgeStorage<T, I> {
 	type Submitter = T::AccountId;
 
 	fn best_block(&self) -> (HeaderId, U256) {
-		BestBlock::get()
+		BestBlock::<I>::get()
 	}
 
 	fn finalized_block(&self) -> HeaderId {
-		FinalizedBlock::get()
+		FinalizedBlock::<I>::get()
 	}
 
 	fn header(&self, hash: &H256) -> Option<(Header, Option<Self::Submitter>)> {
-		Headers::<T>::get(hash).map(|header| (header.header, header.submitter))
+		Headers::<T, I>::get(hash).map(|header| (header.header, header.submitter))
 	}
 
 	fn cached_finality_votes(
@@ -675,7 +679,7 @@ impl<T: Trait> Storage for BridgeStorage<T> {
 		let mut votes = CachedFinalityVotes::default();
 		let mut current_id = *parent;
 		loop {
-			// if we have reached finalized block' sibling => stop with special signal
+			// if we have reached finalized block's sibling => stop with special signal
 			if current_id.number == best_finalized.number && current_id.hash != best_finalized.hash {
 				votes.stopped_at_finalized_sibling = true;
 				return votes;
@@ -687,14 +691,14 @@ impl<T: Trait> Storage for BridgeStorage<T> {
 			}
 
 			// if we have found cached votes => stop
-			let cached_votes = FinalityCache::<T>::get(&current_id.hash);
+			let cached_votes = FinalityCache::<T, I>::get(&current_id.hash);
 			if let Some(cached_votes) = cached_votes {
 				votes.votes = Some(cached_votes);
 				return votes;
 			}
 
 			// read next parent header id
-			let header = match Headers::<T>::get(&current_id.hash) {
+			let header = match Headers::<T, I>::get(&current_id.hash) {
 				Some(header) if header.header.number != 0 => header,
 				_ => return votes,
 			};
@@ -717,10 +721,10 @@ impl<T: Trait> Storage for BridgeStorage<T> {
 		submitter: Option<Self::Submitter>,
 		parent_hash: &H256,
 	) -> Option<ImportContext<Self::Submitter>> {
-		Headers::<T>::get(parent_hash).map(|parent_header| {
-			let validators_set = ValidatorsSets::get(parent_header.next_validators_set_id)
+		Headers::<T, I>::get(parent_hash).map(|parent_header| {
+			let validators_set = ValidatorsSets::<I>::get(parent_header.next_validators_set_id)
 				.expect("validators set is only pruned when last ref is pruned; there is a ref; qed");
-			let parent_scheduled_change = ScheduledChanges::get(parent_hash);
+			let parent_scheduled_change = ScheduledChanges::<I>::get(parent_hash);
 			ImportContext {
 				submitter,
 				parent_hash: *parent_hash,
@@ -735,15 +739,15 @@ impl<T: Trait> Storage for BridgeStorage<T> {
 	}
 
 	fn scheduled_change(&self, hash: &H256) -> Option<ScheduledChange> {
-		ScheduledChanges::get(hash)
+		ScheduledChanges::<I>::get(hash)
 	}
 
 	fn insert_header(&mut self, header: HeaderToImport<Self::Submitter>) {
 		if header.is_best {
-			BestBlock::put((header.id, header.total_difficulty));
+			BestBlock::<I>::put((header.id, header.total_difficulty));
 		}
 		if let Some(scheduled_change) = header.scheduled_change {
-			ScheduledChanges::insert(
+			ScheduledChanges::<I>::insert(
 				&header.id.hash,
 				ScheduledChange {
 					validators: scheduled_change,
@@ -753,12 +757,12 @@ impl<T: Trait> Storage for BridgeStorage<T> {
 		}
 		let next_validators_set_id = match header.enacted_change {
 			Some(enacted_change) => {
-				let next_validators_set_id = NextValidatorsSetId::mutate(|set_id| {
+				let next_validators_set_id = NextValidatorsSetId::<I>::mutate(|set_id| {
 					let next_set_id = *set_id;
 					*set_id += 1;
 					next_set_id
 				});
-				ValidatorsSets::insert(
+				ValidatorsSets::<I>::insert(
 					next_validators_set_id,
 					ValidatorsSet {
 						validators: enacted_change.validators,
@@ -766,11 +770,11 @@ impl<T: Trait> Storage for BridgeStorage<T> {
 						signal_block: enacted_change.signal_block,
 					},
 				);
-				ValidatorsSetsRc::insert(next_validators_set_id, 1);
+				ValidatorsSetsRc::<I>::insert(next_validators_set_id, 1);
 				next_validators_set_id
 			}
 			None => {
-				ValidatorsSetsRc::mutate(header.context.validators_set_id, |rc| {
+				ValidatorsSetsRc::<I>::mutate(header.context.validators_set_id, |rc| {
 					*rc = Some(rc.map(|rc| rc + 1).unwrap_or(1));
 					*rc
 				});
@@ -782,7 +786,7 @@ impl<T: Trait> Storage for BridgeStorage<T> {
 		if let Some(finality_votes_caching_interval) = finality_votes_caching_interval {
 			let cache_entry_required = header.id.number != 0 && header.id.number % finality_votes_caching_interval == 0;
 			if cache_entry_required {
-				FinalityCache::<T>::insert(header.id.hash, header.finality_votes);
+				FinalityCache::<T, I>::insert(header.id.hash, header.finality_votes);
 			}
 		}
 
@@ -794,8 +798,8 @@ impl<T: Trait> Storage for BridgeStorage<T> {
 		);
 
 		let last_signal_block = header.context.last_signal_block();
-		HeadersByNumber::append(header.id.number, header.id.hash);
-		Headers::<T>::insert(
+		HeadersByNumber::<I>::append(header.id.number, header.id.hash);
+		Headers::<T, I>::insert(
 			&header.id.hash,
 			StoredHeader {
 				submitter: header.context.submitter,
@@ -812,7 +816,7 @@ impl<T: Trait> Storage for BridgeStorage<T> {
 		let finalized_number = finalized
 			.as_ref()
 			.map(|f| f.number)
-			.unwrap_or_else(|| FinalizedBlock::get().number);
+			.unwrap_or_else(|| FinalizedBlock::<I>::get().number);
 		if let Some(finalized) = finalized {
 			frame_support::debug::trace!(
 				target: "runtime",
@@ -821,7 +825,7 @@ impl<T: Trait> Storage for BridgeStorage<T> {
 				finalized.hash,
 			);
 
-			FinalizedBlock::put(finalized);
+			FinalizedBlock::<I>::put(finalized);
 		}
 
 		// and now prune headers if we need to
@@ -831,7 +835,7 @@ impl<T: Trait> Storage for BridgeStorage<T> {
 
 /// Initialize storage.
 #[cfg(any(feature = "std", feature = "runtime-benchmarks"))]
-pub(crate) fn initialize_storage<T: Trait>(
+pub(crate) fn initialize_storage<T: Trait<I>, I: Instance>(
 	initial_header: &Header,
 	initial_difficulty: U256,
 	initial_validators: &[Address],
@@ -848,14 +852,14 @@ pub(crate) fn initialize_storage<T: Trait>(
 		number: initial_header.number,
 		hash: initial_hash,
 	};
-	BestBlock::put((initial_id, initial_difficulty));
-	FinalizedBlock::put(initial_id);
-	BlocksToPrune::put(PruningRange {
+	BestBlock::<I>::put((initial_id, initial_difficulty));
+	FinalizedBlock::<I>::put(initial_id);
+	BlocksToPrune::<I>::put(PruningRange {
 		oldest_unpruned_block: initial_header.number,
 		oldest_block_to_keep: initial_header.number,
 	});
-	HeadersByNumber::insert(initial_header.number, vec![initial_hash]);
-	Headers::<T>::insert(
+	HeadersByNumber::<I>::insert(initial_header.number, vec![initial_hash]);
+	Headers::<T, I>::insert(
 		initial_hash,
 		StoredHeader {
 			submitter: None,
@@ -865,8 +869,8 @@ pub(crate) fn initialize_storage<T: Trait>(
 			last_signal_block: None,
 		},
 	);
-	NextValidatorsSetId::put(1);
-	ValidatorsSets::insert(
+	NextValidatorsSetId::<I>::put(1);
+	ValidatorsSets::<I>::insert(
 		0,
 		ValidatorsSet {
 			validators: initial_validators.to_vec(),
@@ -874,7 +878,7 @@ pub(crate) fn initialize_storage<T: Trait>(
 			enact_block: initial_id,
 		},
 	);
-	ValidatorsSetsRc::insert(0, 1);
+	ValidatorsSetsRc::<I>::insert(0, 1);
 }
 
 /// Verify that transaction is included into given finalized block.
@@ -988,7 +992,7 @@ pub(crate) mod tests {
 					);
 
 					if i == 7 && j == 1 {
-						ScheduledChanges::insert(
+						ScheduledChanges::<DefaultInstance>::insert(
 							hash,
 							ScheduledChange {
 								validators: validators_addresses(5),
@@ -997,7 +1001,7 @@ pub(crate) mod tests {
 						);
 					}
 				}
-				HeadersByNumber::insert(i, headers_by_number);
+				HeadersByNumber::<DefaultInstance>::insert(i, headers_by_number);
 			}
 
 			f(BridgeStorage::new())
@@ -1007,16 +1011,16 @@ pub(crate) mod tests {
 	#[test]
 	fn blocks_are_not_pruned_if_range_is_empty() {
 		with_headers_to_prune(|storage| {
-			BlocksToPrune::put(PruningRange {
+			BlocksToPrune::<DefaultInstance>::put(PruningRange {
 				oldest_unpruned_block: 5,
 				oldest_block_to_keep: 5,
 			});
 
 			// try to prune blocks [5; 10)
 			storage.prune_blocks(0xFFFF, 10, 5);
-			assert_eq!(HeadersByNumber::get(&5).unwrap().len(), 5);
+			assert_eq!(HeadersByNumber::<DefaultInstance>::get(&5).unwrap().len(), 5);
 			assert_eq!(
-				BlocksToPrune::get(),
+				BlocksToPrune::<DefaultInstance>::get(),
 				PruningRange {
 					oldest_unpruned_block: 5,
 					oldest_block_to_keep: 5,
@@ -1028,7 +1032,7 @@ pub(crate) mod tests {
 	#[test]
 	fn blocks_to_prune_never_shrinks_from_the_end() {
 		with_headers_to_prune(|storage| {
-			BlocksToPrune::put(PruningRange {
+			BlocksToPrune::<DefaultInstance>::put(PruningRange {
 				oldest_unpruned_block: 0,
 				oldest_block_to_keep: 5,
 			});
@@ -1036,7 +1040,7 @@ pub(crate) mod tests {
 			// try to prune blocks [5; 10)
 			storage.prune_blocks(0xFFFF, 10, 3);
 			assert_eq!(
-				BlocksToPrune::get(),
+				BlocksToPrune::<DefaultInstance>::get(),
 				PruningRange {
 					oldest_unpruned_block: 5,
 					oldest_block_to_keep: 5,
@@ -1050,12 +1054,12 @@ pub(crate) mod tests {
 		with_headers_to_prune(|storage| {
 			// try to prune blocks [0; 10)
 			storage.prune_blocks(0, 10, 10);
-			assert!(HeadersByNumber::get(&0).is_some());
-			assert!(HeadersByNumber::get(&1).is_some());
-			assert!(HeadersByNumber::get(&2).is_some());
-			assert!(HeadersByNumber::get(&3).is_some());
+			assert!(HeadersByNumber::<DefaultInstance>::get(&0).is_some());
+			assert!(HeadersByNumber::<DefaultInstance>::get(&1).is_some());
+			assert!(HeadersByNumber::<DefaultInstance>::get(&2).is_some());
+			assert!(HeadersByNumber::<DefaultInstance>::get(&3).is_some());
 			assert_eq!(
-				BlocksToPrune::get(),
+				BlocksToPrune::<DefaultInstance>::get(),
 				PruningRange {
 					oldest_unpruned_block: 0,
 					oldest_block_to_keep: 10,
@@ -1070,13 +1074,13 @@ pub(crate) mod tests {
 			// try to prune blocks [0; 10)
 			storage.prune_blocks(7, 10, 10);
 			// 1 headers with number = 0 is pruned (1 total)
-			assert!(HeadersByNumber::get(&0).is_none());
+			assert!(HeadersByNumber::<DefaultInstance>::get(&0).is_none());
 			// 5 headers with number = 1 are pruned (6 total)
-			assert!(HeadersByNumber::get(&1).is_none());
+			assert!(HeadersByNumber::<DefaultInstance>::get(&1).is_none());
 			// 1 header with number = 2 are pruned (7 total)
-			assert_eq!(HeadersByNumber::get(&2).unwrap().len(), 4);
+			assert_eq!(HeadersByNumber::<DefaultInstance>::get(&2).unwrap().len(), 4);
 			assert_eq!(
-				BlocksToPrune::get(),
+				BlocksToPrune::<DefaultInstance>::get(),
 				PruningRange {
 					oldest_unpruned_block: 2,
 					oldest_block_to_keep: 10,
@@ -1086,13 +1090,13 @@ pub(crate) mod tests {
 			// try to prune blocks [2; 10)
 			storage.prune_blocks(11, 10, 10);
 			// 4 headers with number = 2 are pruned (4 total)
-			assert!(HeadersByNumber::get(&2).is_none());
+			assert!(HeadersByNumber::<DefaultInstance>::get(&2).is_none());
 			// 5 headers with number = 3 are pruned (9 total)
-			assert!(HeadersByNumber::get(&3).is_none());
+			assert!(HeadersByNumber::<DefaultInstance>::get(&3).is_none());
 			// 2 headers with number = 4 are pruned (11 total)
-			assert_eq!(HeadersByNumber::get(&4).unwrap().len(), 3);
+			assert_eq!(HeadersByNumber::<DefaultInstance>::get(&4).unwrap().len(), 3);
 			assert_eq!(
-				BlocksToPrune::get(),
+				BlocksToPrune::<DefaultInstance>::get(),
 				PruningRange {
 					oldest_unpruned_block: 4,
 					oldest_block_to_keep: 10,
@@ -1109,16 +1113,16 @@ pub(crate) mod tests {
 			// and one of blocks#7 has scheduled change
 			// => we won't prune any block#7 at all
 			storage.prune_blocks(0xFFFF, 5, 10);
-			assert!(HeadersByNumber::get(&0).is_none());
-			assert!(HeadersByNumber::get(&1).is_none());
-			assert!(HeadersByNumber::get(&2).is_none());
-			assert!(HeadersByNumber::get(&3).is_none());
-			assert!(HeadersByNumber::get(&4).is_none());
-			assert!(HeadersByNumber::get(&5).is_none());
-			assert!(HeadersByNumber::get(&6).is_none());
-			assert_eq!(HeadersByNumber::get(&7).unwrap().len(), 5);
+			assert!(HeadersByNumber::<DefaultInstance>::get(&0).is_none());
+			assert!(HeadersByNumber::<DefaultInstance>::get(&1).is_none());
+			assert!(HeadersByNumber::<DefaultInstance>::get(&2).is_none());
+			assert!(HeadersByNumber::<DefaultInstance>::get(&3).is_none());
+			assert!(HeadersByNumber::<DefaultInstance>::get(&4).is_none());
+			assert!(HeadersByNumber::<DefaultInstance>::get(&5).is_none());
+			assert!(HeadersByNumber::<DefaultInstance>::get(&6).is_none());
+			assert_eq!(HeadersByNumber::<DefaultInstance>::get(&7).unwrap().len(), 5);
 			assert_eq!(
-				BlocksToPrune::get(),
+				BlocksToPrune::<DefaultInstance>::get(),
 				PruningRange {
 					oldest_unpruned_block: 7,
 					oldest_block_to_keep: 10,
@@ -1151,7 +1155,7 @@ pub(crate) mod tests {
 			);
 
 			// when we later prune this header, cache entry is removed
-			BlocksToPrune::put(PruningRange {
+			BlocksToPrune::<DefaultInstance>::put(PruningRange {
 				oldest_unpruned_block: interval - 1,
 				oldest_block_to_keep: interval - 1,
 			});
@@ -1238,7 +1242,7 @@ pub(crate) mod tests {
 			insert_header(&mut storage, header1s);
 
 			// header1 is finalized
-			FinalizedBlock::put(header1_id);
+			FinalizedBlock::<DefaultInstance>::put(header1_id);
 
 			// trying to get finality votes when importing header2 -> header1 succeeds
 			assert!(

bridges/modules/ethereum/src/mock.rs

@@ -136,7 +136,7 @@ pub fn run_test_with_genesis<T>(genesis: Header, total_validators: usize, test:
 			initial_difficulty: 0.into(),
 			initial_validators: addresses.clone(),
 		}
-		.build_storage::<TestRuntime>()
+		.build_storage::<TestRuntime, crate::DefaultInstance>()
 		.unwrap(),
 	)
 	.execute_with(|| {

bridges/modules/ethereum/src/test_utils.rs

@@ -63,31 +63,31 @@ impl HeaderBuilder {
 	/// Creates default header on top of test parent with given hash.
 	#[cfg(test)]
 	pub fn with_parent_hash(parent_hash: H256) -> Self {
-		Self::with_parent_hash_on_runtime::<crate::mock::TestRuntime>(parent_hash)
+		Self::with_parent_hash_on_runtime::<crate::mock::TestRuntime, crate::DefaultInstance>(parent_hash)
 	}
 
 	/// Creates default header on top of test parent with given number. First parent is selected.
 	#[cfg(test)]
 	pub fn with_parent_number(parent_number: u64) -> Self {
-		Self::with_parent_number_on_runtime::<crate::mock::TestRuntime>(parent_number)
+		Self::with_parent_number_on_runtime::<crate::mock::TestRuntime, crate::DefaultInstance>(parent_number)
 	}
 
 	/// Creates default header on top of parent with given hash.
-	pub fn with_parent_hash_on_runtime<T: Trait>(parent_hash: H256) -> Self {
+	pub fn with_parent_hash_on_runtime<T: Trait<I>, I: crate::Instance>(parent_hash: H256) -> Self {
 		use crate::Headers;
 		use frame_support::StorageMap;
 
-		let parent_header = Headers::<T>::get(&parent_hash).unwrap().header;
+		let parent_header = Headers::<T, I>::get(&parent_hash).unwrap().header;
 		Self::with_parent(&parent_header)
 	}
 
 	/// Creates default header on top of parent with given number. First parent is selected.
-	pub fn with_parent_number_on_runtime<T: Trait>(parent_number: u64) -> Self {
+	pub fn with_parent_number_on_runtime<T: Trait<I>, I: crate::Instance>(parent_number: u64) -> Self {
 		use crate::HeadersByNumber;
 		use frame_support::StorageMap;
 
-		let parent_hash = HeadersByNumber::get(parent_number).unwrap()[0];
-		Self::with_parent_hash_on_runtime::<T>(parent_hash)
+		let parent_hash = HeadersByNumber::<I>::get(parent_number).unwrap()[0];
+		Self::with_parent_hash_on_runtime::<T, I>(parent_hash)
 	}
 
 	/// Creates default header on top of non-existent parent.

bridges/modules/ethereum/src/validators.rs

@@ -276,6 +276,7 @@ impl ValidatorsSource {
 pub(crate) mod tests {
 	use super::*;
 	use crate::mock::{run_test, validators_addresses, validators_change_receipt, TestRuntime};
+	use crate::DefaultInstance;
 	use crate::{BridgeStorage, Headers, ScheduledChange, ScheduledChanges, StoredHeader};
 	use frame_support::StorageMap;
 	use primitives::compute_merkle_root;
@@ -433,7 +434,7 @@ pub(crate) mod tests {
 			};
 			Headers::<TestRuntime>::insert(id100.hash, header100);
 			if let Some(scheduled_at) = scheduled_at {
-				ScheduledChanges::insert(scheduled_at.hash, scheduled_change);
+				ScheduledChanges::<DefaultInstance>::insert(scheduled_at.hash, scheduled_change);
 			}
 
 			validators.finalize_validators_change(&storage, &finalized_blocks)

bridges/modules/ethereum/src/verification.rs

@@ -361,6 +361,7 @@ mod tests {
 		validators_change_receipt, AccountId, HeaderBuilder, TestRuntime, GAS_LIMIT,
 	};
 	use crate::validators::ValidatorsSource;
+	use crate::DefaultInstance;
 	use crate::{
 		pool_configuration, BridgeStorage, FinalizedBlock, Headers, HeadersByNumber, NextValidatorsSetId,
 		ScheduledChanges, ValidatorsSet, ValidatorsSets,
@@ -402,7 +403,7 @@ mod tests {
 			let block3 = HeaderBuilder::with_parent_number(2).sign_by_set(&validators);
 			insert_header(&mut storage, block3);
 
-			FinalizedBlock::put(block2_id);
+			FinalizedBlock::<DefaultInstance>::put(block2_id);
 
 			let validators_config =
 				ValidatorsConfiguration::Single(ValidatorsSource::Contract(Default::default(), Vec::new()));
@@ -419,21 +420,21 @@ mod tests {
 	}
 
 	fn change_validators_set_at(number: u64, finalized_set: Vec<Address>, signalled_set: Option<Vec<Address>>) {
-		let set_id = NextValidatorsSetId::get();
-		NextValidatorsSetId::put(set_id + 1);
-		ValidatorsSets::insert(
+		let set_id = NextValidatorsSetId::<DefaultInstance>::get();
+		NextValidatorsSetId::<DefaultInstance>::put(set_id + 1);
+		ValidatorsSets::<DefaultInstance>::insert(
 			set_id,
 			ValidatorsSet {
 				validators: finalized_set,
 				signal_block: None,
 				enact_block: HeaderId {
 					number: 0,
-					hash: HeadersByNumber::get(&0).unwrap()[0],
+					hash: HeadersByNumber::<DefaultInstance>::get(&0).unwrap()[0],
 				},
 			},
 		);
 
-		let header_hash = HeadersByNumber::get(&number).unwrap()[0];
+		let header_hash = HeadersByNumber::<DefaultInstance>::get(&number).unwrap()[0];
 		let mut header = Headers::<TestRuntime>::get(&header_hash).unwrap();
 		header.next_validators_set_id = set_id;
 		if let Some(signalled_set) = signalled_set {
@@ -441,7 +442,7 @@ mod tests {
 				number: header.header.number - 1,
 				hash: header.header.parent_hash,
 			});
-			ScheduledChanges::insert(
+			ScheduledChanges::<DefaultInstance>::insert(
 				header.header.parent_hash,
 				ScheduledChange {
 					validators: signalled_set,

bridges/primitives/currency-exchange/src/lib.rs

@@ -134,8 +134,15 @@ impl<Amount> CurrencyConverter for IdentityCurrencyConverter<Amount> {
 }
 
 decl_runtime_apis! {
-	/// API for exchange transactions submitters.
-	pub trait CurrencyExchangeApi<Proof: Parameter> {
+	/// API for Rialto exchange transactions submitters.
+	pub trait RialtoCurrencyExchangeApi<Proof: Parameter> {
+		/// Returns true if currency exchange module is able to import transaction proof in
+		/// its current state.
+		fn filter_transaction_proof(proof: Proof) -> bool;
+	}
+
+	/// API for Kovan exchange transactions submitters.
+	pub trait KovanCurrencyExchangeApi<Proof: Parameter> {
 		/// Returns true if currency exchange module is able to import transaction proof in
 		/// its current state.
 		fn filter_transaction_proof(proof: Proof) -> bool;

bridges/primitives/ethereum-poa/src/lib.rs

@@ -505,19 +505,32 @@ pub fn step_validator<T>(header_validators: &[T], header_step: u64) -> &T {
 }
 
 sp_api::decl_runtime_apis! {
-	/// API for headers submitters.
-	pub trait EthereumHeadersApi {
+	/// API for querying information about headers from the Rialto Bridge Pallet
+	pub trait RialtoHeaderApi {
 		/// Returns number and hash of the best block known to the bridge module.
-		/// The caller should only submit `import_header` transaction that makes
+		///
+		/// The caller should only submit an `import_header` transaction that makes
 		/// (or leads to making) other header the best one.
 		fn best_block() -> (u64, H256);
-
 		/// Returns number and hash of the best finalized block known to the bridge module.
 		fn finalized_block() -> (u64, H256);
-
 		/// Returns true if the import of given block requires transactions receipts.
 		fn is_import_requires_receipts(header: Header) -> bool;
+		/// Returns true if header is known to the runtime.
+		fn is_known_block(hash: H256) -> bool;
+	}
 
+	/// API for querying information about headers from the Kovan Bridge Pallet
+	pub trait KovanHeaderApi {
+		/// Returns number and hash of the best block known to the bridge module.
+		///
+		/// The caller should only submit an `import_header` transaction that makes
+		/// (or leads to making) other header the best one.
+		fn best_block() -> (u64, H256);
+		/// Returns number and hash of the best finalized block known to the bridge module.
+		fn finalized_block() -> (u64, H256);
+		/// Returns true if the import of given block requires transactions receipts.
+		fn is_import_requires_receipts(header: Header) -> bool;
 		/// Returns true if header is known to the runtime.
 		fn is_known_block(hash: H256) -> bool;
 	}

bridges/relays/ethereum/src/substrate_client.rs

@@ -34,10 +34,10 @@ use sp_core::crypto::Pair;
 use sp_runtime::traits::IdentifyAccount;
 use std::collections::VecDeque;
 
-const ETH_API_IMPORT_REQUIRES_RECEIPTS: &str = "EthereumHeadersApi_is_import_requires_receipts";
-const ETH_API_IS_KNOWN_BLOCK: &str = "EthereumHeadersApi_is_known_block";
-const ETH_API_BEST_BLOCK: &str = "EthereumHeadersApi_best_block";
-const ETH_API_BEST_FINALIZED_BLOCK: &str = "EthereumHeadersApi_finalized_block";
+const ETH_API_IMPORT_REQUIRES_RECEIPTS: &str = "RialtoHeaderApi_is_import_requires_receipts";
+const ETH_API_IS_KNOWN_BLOCK: &str = "RialtoHeaderApi_is_known_block";
+const ETH_API_BEST_BLOCK: &str = "RialtoHeaderApi_best_block";
+const ETH_API_BEST_FINALIZED_BLOCK: &str = "RialtoHeaderApi_finalized_block";
 const EXCH_API_FILTER_TRANSACTION_PROOF: &str = "CurrencyExchangeApi_filter_transaction_proof";
 const SUB_API_GRANDPA_AUTHORITIES: &str = "GrandpaApi_grandpa_authorities";
 
@@ -336,7 +336,8 @@ impl SubmitEthereumExchangeTransactionProof for SubstrateRpcClient {
 		let nonce = self.next_account_index(account_id).await?;
 
 		let transaction = create_signed_transaction(
-			bridge_node_runtime::Call::BridgeCurrencyExchange(
+			// TODO [#209]: Change so that that it's dynamic
+			bridge_node_runtime::Call::BridgeRialtoCurrencyExchange(
 				bridge_node_runtime::BridgeCurrencyExchangeCall::import_peer_transaction(proof),
 			),
 			&params.signer,
@@ -356,7 +357,8 @@ fn create_signed_submit_transaction(
 	genesis_hash: H256,
 ) -> bridge_node_runtime::UncheckedExtrinsic {
 	create_signed_transaction(
-		bridge_node_runtime::Call::BridgeEthPoA(bridge_node_runtime::BridgeEthPoACall::import_signed_headers(
+		// TODO [#209]: Change so that that it's dynamic
+		bridge_node_runtime::Call::BridgeRialto(bridge_node_runtime::BridgeEthPoACall::import_signed_headers(
 			headers
 				.into_iter()
 				.map(|header| {
@@ -376,7 +378,8 @@ fn create_signed_submit_transaction(
 /// Create unsigned Substrate transaction for submitting Ethereum header.
 fn create_unsigned_submit_transaction(header: QueuedEthereumHeader) -> bridge_node_runtime::UncheckedExtrinsic {
 	let function =
-		bridge_node_runtime::Call::BridgeEthPoA(bridge_node_runtime::BridgeEthPoACall::import_unsigned_header(
+		// TODO [#209]: Change so that that it's dynamic
+		bridge_node_runtime::Call::BridgeRialto(bridge_node_runtime::BridgeEthPoACall::import_unsigned_header(
 			into_substrate_ethereum_header(header.header()),
 			into_substrate_ethereum_receipts(header.extra()),
 		));