Refactor message relay helpers (#1234)

* refactor message relay helpers

* single standalone_metrics function

* fixed tests

* clippy + fmt

* removed commented code

* add calls tracing

* fix spelling

* cargo fmt

* -commented code

* fix build again

* post-merge build fix

* clippy + fmt

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

@@ -14,9 +14,10 @@
 // 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 bp_messages::MessageNonce;
 use bp_runtime::{Chain as ChainBase, HashOf, TransactionEraOf};
 use codec::{Codec, Encode};
-use frame_support::weights::WeightToFeePolynomial;
+use frame_support::weights::{Weight, WeightToFeePolynomial};
 use jsonrpsee_ws_client::types::{DeserializeOwned, Serialize};
 use num_traits::Zero;
 use sc_transaction_pool_api::TransactionStatus;
@@ -32,6 +33,11 @@ use std::{fmt::Debug, time::Duration};
 pub trait Chain: ChainBase + Clone {
 	/// Chain name.
 	const NAME: &'static str;
+	/// Identifier of the basic token of the chain (if applicable).
+	///
+	/// This identifier is used to fetch token price. In case of testnets, you may either
+	/// set it to `None`, or associate testnet with one of the existing tokens.
+	const TOKEN_ID: Option<&'static str>;
 	/// Name of the runtime API method that is returning best known finalized header number
 	/// and hash (as tuple).
 	///
@@ -52,12 +58,56 @@ pub trait Chain: ChainBase + Clone {
 	/// Block type.
 	type SignedBlock: Member + Serialize + DeserializeOwned + BlockWithJustification<Self::Header>;
 	/// The aggregated `Call` type.
-	type Call: Clone + Dispatchable + Debug + Send;
+	type Call: Clone + Codec + Dispatchable + Debug + Send;
 
 	/// Type that is used by the chain, to convert from weight to fee.
 	type WeightToFee: WeightToFeePolynomial<Balance = Self::Balance>;
 }
 
+/// Substrate-based chain with messaging support from minimal relay-client point of view.
+pub trait ChainWithMessages: Chain {
+	/// Name of the bridge messages pallet (used in `construct_runtime` macro call) that is deployed
+	/// at some other chain to bridge with this `ChainWithMessages`.
+	///
+	/// We assume that all chains that are bridging with this `ChainWithMessages` are using
+	/// the same name.
+	const WITH_CHAIN_MESSAGES_PALLET_NAME: &'static str;
+
+	/// Name of the `To<ChainWithMessages>OutboundLaneApi::message_details` runtime API method.
+	/// The method is provided by the runtime that is bridged with this `ChainWithMessages`.
+	const TO_CHAIN_MESSAGE_DETAILS_METHOD: &'static str;
+	/// Name of the `To<ChainWithMessages>OutboundLaneApi::latest_generated_nonce` runtime API
+	/// method. The method is provided by the runtime that is bridged with this `ChainWithMessages`.
+	const TO_CHAIN_LATEST_GENERATED_NONCE_METHOD: &'static str;
+	/// Name of the `To<ChainWithMessages>OutboundLaneApi::latest_received_nonce` runtime API
+	/// method. The method is provided by the runtime that is bridged with this `ChainWithMessages`.
+	const TO_CHAIN_LATEST_RECEIVED_NONCE_METHOD: &'static str;
+
+	/// Name of the `From<ChainWithMessages>InboundLaneApi::latest_received_nonce` runtime method.
+	/// The method is provided by the runtime that is bridged with this `ChainWithMessages`.
+	const FROM_CHAIN_LATEST_RECEIVED_NONCE_METHOD: &'static str;
+	/// Name of the `From<ChainWithMessages>InboundLaneApi::latest_confirmed_nonce` runtime method.
+	/// The method is provided by the runtime that is bridged with this `ChainWithMessages`.
+	const FROM_CHAIN_LATEST_CONFIRMED_NONCE_METHOD: &'static str;
+	/// Name of the `From<ChainWithMessages>InboundLaneApi::unrewarded_relayers_state` runtime
+	/// method. The method is provided by the runtime that is bridged with this `ChainWithMessages`.
+	const FROM_CHAIN_UNREWARDED_RELAYERS_STATE: &'static str;
+
+	/// Additional weight of the dispatch fee payment if dispatch is paid at the target chain
+	/// and this `ChainWithMessages` is the target chain.
+	const PAY_INBOUND_DISPATCH_FEE_WEIGHT_AT_CHAIN: Weight;
+
+	/// Maximal number of unrewarded relayers in a single confirmation transaction at this
+	/// `ChainWithMessages`.
+	const MAX_UNREWARDED_RELAYERS_IN_CONFIRMATION_TX: MessageNonce;
+	/// Maximal number of unconfirmed messages in a single confirmation transaction at this
+	/// `ChainWithMessages`.
+	const MAX_UNCONFIRMED_MESSAGES_IN_CONFIRMATION_TX: MessageNonce;
+
+	/// Weights of message pallet calls.
+	type WeightInfo: pallet_bridge_messages::WeightInfoExt;
+}
+
 /// Call type used by the chain.
 pub type CallOf<C> = <C as Chain>::Call;
 /// Weight-to-Fee type used by the chain.

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

@@ -181,7 +181,7 @@ impl<C: ChainWithBalances> Environment<C> for Client<C> {
 #[cfg(test)]
 mod tests {
 	use super::*;
-	use frame_support::weights::IdentityFee;
+	use frame_support::weights::{IdentityFee, Weight};
 	use futures::{
 		channel::mpsc::{unbounded, UnboundedReceiver, UnboundedSender},
 		future::FutureExt,
@@ -202,10 +202,18 @@ mod tests {
 		type Balance = u32;
 		type Index = u32;
 		type Signature = sp_runtime::testing::TestSignature;
+
+		fn max_extrinsic_size() -> u32 {
+			unreachable!()
+		}
+		fn max_extrinsic_weight() -> Weight {
+			unreachable!()
+		}
 	}
 
 	impl Chain for TestChain {
 		const NAME: &'static str = "Test";
+		const TOKEN_ID: Option<&'static str> = None;
 		const BEST_FINALIZED_HEADER_ID_METHOD: &'static str = "BestTestHeader";
 		const AVERAGE_BLOCK_INTERVAL: Duration = Duration::from_millis(1);
 		const STORAGE_PROOF_OVERHEAD: u32 = 0;

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

@@ -32,7 +32,8 @@ use std::time::Duration;
 pub use crate::{
 	chain::{
 		AccountKeyPairOf, BlockWithJustification, CallOf, Chain, ChainWithBalances,
-		TransactionSignScheme, TransactionStatusOf, UnsignedTransaction, WeightToFeeOf,
+		ChainWithMessages, TransactionSignScheme, TransactionStatusOf, UnsignedTransaction,
+		WeightToFeeOf,
 	},
 	client::{Client, OpaqueGrandpaAuthoritiesSet, Subscription},
 	error::{Error, Result},