Westend<>Rococo Headers Relay (#875)

* Add modules for Rococo<>Westend header sync

* Use mock Westend and Rococo finaltiy tx calls

* Add Westend<>Rococo variants to `init_bridge`

* Add Westend<>Rococo variants to `relay_headers`

* Simplify the Rococo and Westend signing params

* Add `submit_finality_proof` mock Call variant

* Add note to more closely match `initialize` Call variant

* Accidentally committed `cargo-expand`ed code 🤦

* Add `initialize` Call variant to Rococo mock

* Fix call enums.

* Add explainatory comment.

* clippy.

* Add issue number.

* De-duplicate metrics customisation.

* Add comments to Rococo/Westend runtimes.

* Add scale-encoding compatibility test.

* Fix tests.

* Clippy.

Co-authored-by: Tomasz Drwięga <tomasz@parity.io>

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

@@ -15,9 +15,9 @@
 // along with Parity Bridges Common.  If not, see <http://www.gnu.org/licenses/>.
 
 use crate::cli::{SourceConnectionParams, TargetConnectionParams, TargetSigningParams};
+use bp_header_chain::InitializationData;
 use bp_runtime::Chain as ChainBase;
 use codec::Encode;
-use pallet_bridge_grandpa::InitializationData;
 use relay_substrate_client::{Chain, TransactionSignScheme};
 use sp_core::{Bytes, Pair};
 use structopt::{clap::arg_enum, StructOpt};
@@ -44,6 +44,8 @@ arg_enum! {
 		MillauToRialto,
 		RialtoToMillau,
 		WestendToMillau,
+		WestendToRococo,
+		RococoToWestend,
 	}
 }
 
@@ -98,6 +100,30 @@ macro_rules! select_bridge {
 					.into()
 				}
 
+				$generic
+			}
+			InitBridgeName::WestendToRococo => {
+				type Source = relay_westend_client::Westend;
+				type Target = relay_rococo_client::Rococo;
+
+				fn encode_init_bridge(
+					init_data: InitializationData<<Source as ChainBase>::Header>,
+				) -> <Target as Chain>::Call {
+					bp_rococo::Call::BridgeGrandpaWestend(bp_rococo::BridgeGrandpaWestendCall::initialize(init_data))
+				}
+
+				$generic
+			}
+			InitBridgeName::RococoToWestend => {
+				type Source = relay_rococo_client::Rococo;
+				type Target = relay_westend_client::Westend;
+
+				fn encode_init_bridge(
+					init_data: InitializationData<<Source as ChainBase>::Header>,
+				) -> <Target as Chain>::Call {
+					bp_westend::Call::BridgeGrandpaRococo(bp_westend::BridgeGrandpaRococoCall::initialize(init_data))
+				}
+
 				$generic
 			}
 		}

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

@@ -373,6 +373,7 @@ macro_rules! declare_chain_options {
 				/// Parse signing params into chain-specific KeyPair.
 				pub fn to_keypair<Chain: CliChain>(&self) -> anyhow::Result<Chain::KeyPair> {
 					use sp_core::crypto::Pair;
+
 					Chain::KeyPair::from_string(
 						&self.[<$chain_prefix _signer>],
 						self.[<$chain_prefix _signer_password>].as_deref()

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

@@ -42,6 +42,8 @@ arg_enum! {
 		MillauToRialto,
 		RialtoToMillau,
 		WestendToMillau,
+		WestendToRococo,
+		RococoToWestend,
 	}
 }
 
@@ -67,6 +69,20 @@ macro_rules! select_bridge {
 				type Target = relay_millau_client::Millau;
 				type Finality = crate::rialto_millau::westend_headers_to_millau::WestendFinalityToMillau;
 
+				$generic
+			}
+			RelayHeadersBridge::WestendToRococo => {
+				type Source = relay_westend_client::Westend;
+				type Target = relay_rococo_client::Rococo;
+				type Finality = crate::rialto_millau::westend_headers_to_rococo::WestendFinalityToRococo;
+
+				$generic
+			}
+			RelayHeadersBridge::RococoToWestend => {
+				type Source = relay_rococo_client::Rococo;
+				type Target = relay_westend_client::Westend;
+				type Finality = crate::rialto_millau::rococo_headers_to_westend::RococoFinalityToWestend;
+
 				$generic
 			}
 		}

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

@@ -21,6 +21,7 @@
 //! and authorities set from source to target chain. The headers sync starts
 //! with this header.
 
+use bp_header_chain::InitializationData;
 use bp_header_chain::{
 	find_grandpa_authorities_scheduled_change,
 	justification::{verify_justification, GrandpaJustification},
@@ -28,7 +29,6 @@ use bp_header_chain::{
 use codec::Decode;
 use finality_grandpa::voter_set::VoterSet;
 use num_traits::{One, Zero};
-use pallet_bridge_grandpa::InitializationData;
 use relay_substrate_client::{Chain, Client};
 use sp_core::Bytes;
 use sp_finality_grandpa::AuthorityList as GrandpaAuthoritiesSet;

bridges/relays/bin-substrate/src/rialto_millau/mod.rs

@@ -20,7 +20,9 @@ pub mod millau_headers_to_rialto;
 pub mod millau_messages_to_rialto;
 pub mod rialto_headers_to_millau;
 pub mod rialto_messages_to_millau;
+pub mod rococo_headers_to_westend;
 pub mod westend_headers_to_millau;
+pub mod westend_headers_to_rococo;
 
 use crate::cli::{
 	bridge,
@@ -32,9 +34,44 @@ use frame_support::weights::{GetDispatchInfo, Weight};
 use pallet_bridge_dispatch::{CallOrigin, MessagePayload};
 use relay_millau_client::Millau;
 use relay_rialto_client::Rialto;
+use relay_rococo_client::Rococo;
+use relay_utils::metrics::{FloatJsonValueMetric, MetricsParams};
 use relay_westend_client::Westend;
 use sp_version::RuntimeVersion;
 
+pub(crate) fn add_polkadot_kusama_price_metrics<T: finality_relay::FinalitySyncPipeline>(
+	params: MetricsParams,
+) -> anyhow::Result<MetricsParams> {
+	Ok(
+		relay_utils::relay_metrics(Some(finality_relay::metrics_prefix::<T>()), params)
+			// Polkadot/Kusama prices are added as metrics here, because atm we don't have Polkadot <-> Kusama
+			// relays, but we want to test metrics/dashboards in advance
+			.standalone_metric(|registry, prefix| {
+				FloatJsonValueMetric::new(
+					registry,
+					prefix,
+					"https://api.coingecko.com/api/v3/simple/price?ids=Polkadot&vs_currencies=usd".into(),
+					"$.polkadot.usd".into(),
+					"polkadot_price".into(),
+					"Polkadot price in USD".into(),
+				)
+			})
+			.map_err(|e| anyhow::format_err!("{}", e))?
+			.standalone_metric(|registry, prefix| {
+				FloatJsonValueMetric::new(
+					registry,
+					prefix,
+					"https://api.coingecko.com/api/v3/simple/price?ids=Kusama&vs_currencies=usd".into(),
+					"$.kusama.usd".into(),
+					"kusama_price".into(),
+					"Kusama price in USD".into(),
+				)
+			})
+			.map_err(|e| anyhow::format_err!("{}", e))?
+			.into_params(),
+	)
+}
+
 impl CliEncodeCall for Millau {
 	fn max_extrinsic_size() -> u32 {
 		bp_millau::max_extrinsic_size()
@@ -197,6 +234,25 @@ impl CliChain for Westend {
 	}
 }
 
+impl CliChain for Rococo {
+	const RUNTIME_VERSION: RuntimeVersion = bp_rococo::VERSION;
+
+	type KeyPair = sp_core::sr25519::Pair;
+	type MessagePayload = ();
+
+	fn ss58_format() -> u16 {
+		42
+	}
+
+	fn max_extrinsic_weight() -> Weight {
+		0
+	}
+
+	fn encode_message(_message: encode_message::MessagePayload) -> Result<Self::MessagePayload, String> {
+		Err("Sending messages from Rococo is not yet supported.".into())
+	}
+}
+
 #[cfg(test)]
 mod tests {
 	use super::*;
@@ -373,3 +429,89 @@ mod tests {
 		);
 	}
 }
+
+#[cfg(test)]
+mod rococo_tests {
+	use bp_header_chain::justification::GrandpaJustification;
+	use codec::Encode;
+
+	#[test]
+	fn scale_compatibility_of_bridges_call() {
+		// given
+		let header = sp_runtime::generic::Header {
+			parent_hash: Default::default(),
+			number: Default::default(),
+			state_root: Default::default(),
+			extrinsics_root: Default::default(),
+			digest: sp_runtime::generic::Digest { logs: vec![] },
+		};
+		let justification = GrandpaJustification {
+			round: 0,
+			commit: finality_grandpa::Commit {
+				target_hash: Default::default(),
+				target_number: Default::default(),
+				precommits: vec![],
+			},
+			votes_ancestries: vec![],
+		};
+		let actual = bp_rococo::BridgeGrandpaWestendCall::submit_finality_proof(header.clone(), justification.clone());
+		let expected = millau_runtime::BridgeGrandpaRialtoCall::<millau_runtime::Runtime>::submit_finality_proof(
+			header,
+			justification,
+		);
+
+		// when
+		let actual_encoded = actual.encode();
+		let expected_encoded = expected.encode();
+
+		// then
+		assert_eq!(
+			actual_encoded, expected_encoded,
+			"Encoding difference. Raw: {:?} vs {:?}",
+			actual, expected
+		);
+	}
+}
+
+#[cfg(test)]
+mod westend_tests {
+	use bp_header_chain::justification::GrandpaJustification;
+	use codec::Encode;
+
+	#[test]
+	fn scale_compatibility_of_bridges_call() {
+		// given
+		let header = sp_runtime::generic::Header {
+			parent_hash: Default::default(),
+			number: Default::default(),
+			state_root: Default::default(),
+			extrinsics_root: Default::default(),
+			digest: sp_runtime::generic::Digest { logs: vec![] },
+		};
+		let justification = GrandpaJustification {
+			round: 0,
+			commit: finality_grandpa::Commit {
+				target_hash: Default::default(),
+				target_number: Default::default(),
+				precommits: vec![],
+			},
+			votes_ancestries: vec![],
+		};
+		let actual = bp_westend::BridgeGrandpaRococoCall::submit_finality_proof(header.clone(), justification.clone());
+		let expected = millau_runtime::BridgeGrandpaRialtoCall::<millau_runtime::Runtime>::submit_finality_proof(
+			header,
+			justification,
+		);
+
+		// when
+		let actual_encoded = actual.encode();
+		let expected_encoded = expected.encode();
+
+		// then
+		assert_eq!(
+			actual_encoded, expected_encoded,
+			"Encoding difference. Raw: {:?} vs {:?}",
+			actual, expected
+		);
+	}
+}

bridges/relays/bin-substrate/src/rialto_millau/rococo_headers_to_westend.rs

@@ -0,0 +1,60 @@
+// Copyright 2019-2021 Parity Technologies (UK) Ltd.
+// This file is part of Parity Bridges Common.
+
+// Parity Bridges Common is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// Parity Bridges Common is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// 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/>.
+
+//! Rococo-to-Westend headers sync entrypoint.
+
+use crate::finality_pipeline::{SubstrateFinalitySyncPipeline, SubstrateFinalityToSubstrate};
+
+use bp_header_chain::justification::GrandpaJustification;
+use codec::Encode;
+use relay_rococo_client::{Rococo, SyncHeader as RococoSyncHeader};
+use relay_substrate_client::{Chain, TransactionSignScheme};
+use relay_utils::metrics::MetricsParams;
+use relay_westend_client::{SigningParams as WestendSigningParams, Westend};
+use sp_core::{Bytes, Pair};
+
+/// Rococo-to-Westend finality sync pipeline.
+pub(crate) type RococoFinalityToWestend = SubstrateFinalityToSubstrate<Rococo, Westend, WestendSigningParams>;
+
+impl SubstrateFinalitySyncPipeline for RococoFinalityToWestend {
+	const BEST_FINALIZED_SOURCE_HEADER_ID_AT_TARGET: &'static str = bp_rococo::BEST_FINALIZED_ROCOCO_HEADER_METHOD;
+
+	type TargetChain = Westend;
+
+	fn customize_metrics(params: MetricsParams) -> anyhow::Result<MetricsParams> {
+		crate::rialto_millau::add_polkadot_kusama_price_metrics::<Self>(params)
+	}
+
+	fn transactions_author(&self) -> bp_westend::AccountId {
+		(*self.target_sign.public().as_array_ref()).into()
+	}
+
+	fn make_submit_finality_proof_transaction(
+		&self,
+		transaction_nonce: <Westend as Chain>::Index,
+		header: RococoSyncHeader,
+		proof: GrandpaJustification<bp_rococo::Header>,
+	) -> Bytes {
+		let call = bp_westend::Call::BridgeGrandpaRococo(bp_westend::BridgeGrandpaRococoCall::submit_finality_proof(
+			header.into_inner(),
+			proof,
+		));
+		let genesis_hash = *self.target_client.genesis_hash();
+		let transaction = Westend::sign_transaction(genesis_hash, &self.target_sign, transaction_nonce, call);
+
+		Bytes(transaction.encode())
+	}
+}

bridges/relays/bin-substrate/src/rialto_millau/westend_headers_to_millau.rs

@@ -22,7 +22,7 @@ use bp_header_chain::justification::GrandpaJustification;
 use codec::Encode;
 use relay_millau_client::{Millau, SigningParams as MillauSigningParams};
 use relay_substrate_client::{Chain, TransactionSignScheme};
-use relay_utils::metrics::{FloatJsonValueMetric, MetricsParams};
+use relay_utils::metrics::MetricsParams;
 use relay_westend_client::{SyncHeader as WestendSyncHeader, Westend};
 use sp_core::{Bytes, Pair};
 
@@ -35,34 +35,7 @@ impl SubstrateFinalitySyncPipeline for WestendFinalityToMillau {
 	type TargetChain = Millau;
 
 	fn customize_metrics(params: MetricsParams) -> anyhow::Result<MetricsParams> {
-		Ok(
-			relay_utils::relay_metrics(Some(finality_relay::metrics_prefix::<Self>()), params)
-				// Polkadot/Kusama prices are added as metrics here, because atm we don't have Polkadot <-> Kusama
-				// relays, but we want to test metrics/dashboards in advance
-				.standalone_metric(|registry, prefix| {
-					FloatJsonValueMetric::new(
-						registry,
-						prefix,
-						"https://api.coingecko.com/api/v3/simple/price?ids=Polkadot&vs_currencies=usd".into(),
-						"$.polkadot.usd".into(),
-						"polkadot_price".into(),
-						"Polkadot price in USD".into(),
-					)
-				})
-				.map_err(|e| anyhow::format_err!("{}", e))?
-				.standalone_metric(|registry, prefix| {
-					FloatJsonValueMetric::new(
-						registry,
-						prefix,
-						"https://api.coingecko.com/api/v3/simple/price?ids=Kusama&vs_currencies=usd".into(),
-						"$.kusama.usd".into(),
-						"kusama_price".into(),
-						"Kusama price in USD".into(),
-					)
-				})
-				.map_err(|e| anyhow::format_err!("{}", e))?
-				.into_params(),
-		)
+		crate::rialto_millau::add_polkadot_kusama_price_metrics::<Self>(params)
 	}
 
 	fn transactions_author(&self) -> bp_millau::AccountId {

bridges/relays/bin-substrate/src/rialto_millau/westend_headers_to_rococo.rs

@@ -0,0 +1,60 @@
+// Copyright 2019-2021 Parity Technologies (UK) Ltd.
+// This file is part of Parity Bridges Common.
+
+// Parity Bridges Common is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// Parity Bridges Common is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// 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/>.
+
+//! Westend-to-Rococo headers sync entrypoint.
+
+use crate::finality_pipeline::{SubstrateFinalitySyncPipeline, SubstrateFinalityToSubstrate};
+
+use bp_header_chain::justification::GrandpaJustification;
+use codec::Encode;
+use relay_rococo_client::{Rococo, SigningParams as RococoSigningParams};
+use relay_substrate_client::{Chain, TransactionSignScheme};
+use relay_utils::metrics::MetricsParams;
+use relay_westend_client::{SyncHeader as WestendSyncHeader, Westend};
+use sp_core::{Bytes, Pair};
+
+/// Westend-to-Rococo finality sync pipeline.
+pub(crate) type WestendFinalityToRococo = SubstrateFinalityToSubstrate<Westend, Rococo, RococoSigningParams>;
+
+impl SubstrateFinalitySyncPipeline for WestendFinalityToRococo {
+	const BEST_FINALIZED_SOURCE_HEADER_ID_AT_TARGET: &'static str = bp_westend::BEST_FINALIZED_WESTEND_HEADER_METHOD;
+
+	type TargetChain = Rococo;
+
+	fn customize_metrics(params: MetricsParams) -> anyhow::Result<MetricsParams> {
+		crate::rialto_millau::add_polkadot_kusama_price_metrics::<Self>(params)
+	}
+
+	fn transactions_author(&self) -> bp_rococo::AccountId {
+		(*self.target_sign.public().as_array_ref()).into()
+	}
+
+	fn make_submit_finality_proof_transaction(
+		&self,
+		transaction_nonce: <Rococo as Chain>::Index,
+		header: WestendSyncHeader,
+		proof: GrandpaJustification<bp_westend::Header>,
+	) -> Bytes {
+		let call = bp_rococo::Call::BridgeGrandpaWestend(bp_rococo::BridgeGrandpaWestendCall::submit_finality_proof(
+			header.into_inner(),
+			proof,
+		));
+		let genesis_hash = *self.target_client.genesis_hash();
+		let transaction = Rococo::sign_transaction(genesis_hash, &self.target_sign, transaction_nonce, call);
+
+		Bytes(transaction.encode())
+	}
+}