Millau -> Rialto headers relay (#398)

* working-millau-to-rialto-relay

* fix Millau state root

* properly fix synced+incomplete headers for sub2sub

* removed wrong TODO

* fmt + clippy

* Update relays/headers-relay/src/headers.rs

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

* moved SubstrateTransactionMaker definition

* removed M from phantomdata

* removed prune_synced_children

* methods names as consts

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

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

@@ -62,6 +62,7 @@ pub use frame_support::{
 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_substrate_bridge::Call as BridgeMillauCall;
 pub use pallet_timestamp::Call as TimestampCall;
 
 #[cfg(any(feature = "std", test))]

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

@@ -36,7 +36,7 @@ pub fn initial_header() -> Header {
 	Header {
 		parent_hash: Default::default(),
 		number: Default::default(),
-		state_root: hex!("bb65e8ba99408ebfefea9d28f74403d41da6858fa075c51fcc71dc383455c530").into(),
+		state_root: hex!("e901070e3bb061a6ae9ea8e4ba5417bf4c4642f9e75af9d372861c170ba7a9a3").into(),
 		extrinsics_root: hex!("03170a2e7597b7b7e3d84c05391d139a62b157e78786d8c082f29dcf4c111314").into(),
 		digest: Default::default(),
 	}

bridges/primitives/millau/src/lib.rs

@@ -49,6 +49,13 @@ impl Chain for Millau {
 	type Header = Header;
 }
 
+/// Name of the `MillauHeaderApi::best_block` runtime method.
+pub const BEST_MILLAU_BLOCK_METHOD: &str = "MillauHeaderApi_best_block";
+/// Name of the `MillauHeaderApi::is_known_block` runtime method.
+pub const IS_KNOWN_MILLAU_BLOCK_METHOD: &str = "MillauHeaderApi_is_known_block";
+/// Name of the `MillauHeaderApi::incomplete_headers` runtime method.
+pub const INCOMPLETE_MILLAU_HEADERS_METHOD: &str = "MillauHeaderApi_incomplete_headers";
+
 sp_api::decl_runtime_apis! {
 	/// API for querying information about Millau headers from the Bridge Pallet instance.
 	///

bridges/relays/headers-relay/src/headers.rs

@@ -32,6 +32,8 @@ use std::{
 
 type HeadersQueue<P> =
 	BTreeMap<<P as HeadersSyncPipeline>::Number, HashMap<<P as HeadersSyncPipeline>::Hash, QueuedHeader<P>>>;
+type SyncedChildren<P> =
+	BTreeMap<<P as HeadersSyncPipeline>::Number, HashMap<<P as HeadersSyncPipeline>::Hash, HashSet<HeaderIdOf<P>>>>;
 type KnownHeaders<P> =
 	BTreeMap<<P as HeadersSyncPipeline>::Number, HashMap<<P as HeadersSyncPipeline>::Hash, HeaderStatus>>;
 
@@ -63,6 +65,9 @@ pub struct QueuedHeaders<P: HeadersSyncPipeline> {
 	/// Headers that are (we believe) currently submitted to target node by our,
 	/// not-yet mined transactions.
 	submitted: HeadersQueue<P>,
+	/// Synced headers childrens. We need it to support case when header is synced, but some of
+	/// its parents are incomplete.
+	synced_children: SyncedChildren<P>,
 	/// Pointers to all headers that we ever seen and we believe we can touch in the future.
 	known_headers: KnownHeaders<P>,
 	/// Headers that are waiting for completion data from source node. Mapped (and auto-sorted
@@ -96,6 +101,7 @@ impl<P: HeadersSyncPipeline> Default for QueuedHeaders<P> {
 			ready: HeadersQueue::new(),
 			incomplete: HeadersQueue::new(),
 			submitted: HeadersQueue::new(),
+			synced_children: SyncedChildren::<P>::new(),
 			known_headers: KnownHeaders::<P>::new(),
 			incomplete_headers: LinkedHashMap::new(),
 			completion_data: LinkedHashMap::new(),
@@ -419,13 +425,17 @@ impl<P: HeadersSyncPipeline> QueuedHeaders<P> {
 				self.header_synced(&new_incomplete_header);
 			}
 
-			move_header_descendants::<P>(
+			let move_origins = select_synced_children::<P>(&self.synced_children, &new_incomplete_header);
-				&mut [&mut self.ready, &mut self.submitted],
+			let move_origins = move_origins.into_iter().chain(std::iter::once(new_incomplete_header));
-				&mut self.incomplete,
+			for move_origin in move_origins {
-				&mut self.known_headers,
+				move_header_descendants::<P>(
-				HeaderStatus::Incomplete,
+					&mut [&mut self.ready, &mut self.submitted],
-				&new_incomplete_header,
+					&mut self.incomplete,
-			);
+					&mut self.known_headers,
+					HeaderStatus::Incomplete,
+					&move_origin,
+				);
+			}
 
 			if make_header_incomplete {
 				log::debug!(
@@ -460,13 +470,20 @@ impl<P: HeadersSyncPipeline> QueuedHeaders<P> {
 			.cloned()
 			.collect::<Vec<_>>();
 		for just_completed_header in just_completed_headers {
-			move_header_descendants::<P>(
+			// sub2eth rejects H if H.Parent is incomplete
-				&mut [&mut self.incomplete],
+			// sub2sub allows 'syncing' headers like that
-				&mut self.ready,
+			// => let's check if there are some synced children of just completed header
-				&mut self.known_headers,
+			let move_origins = select_synced_children::<P>(&self.synced_children, &just_completed_header);
-				HeaderStatus::Ready,
+			let move_origins = move_origins.into_iter().chain(std::iter::once(just_completed_header));
-				&just_completed_header,
+			for move_origin in move_origins {
-			);
+				move_header_descendants::<P>(
+					&mut [&mut self.incomplete],
+					&mut self.ready,
+					&mut self.known_headers,
+					HeaderStatus::Ready,
+					&move_origin,
+				);
+			}
 
 			log::debug!(
 				target: "bridge",
@@ -514,6 +531,7 @@ impl<P: HeadersSyncPipeline> QueuedHeaders<P> {
 		prune_queue(&mut self.ready, prune_border);
 		prune_queue(&mut self.submitted, prune_border);
 		prune_queue(&mut self.incomplete, prune_border);
+		self.synced_children = self.synced_children.split_off(&prune_border);
 		prune_known_headers::<P>(&mut self.known_headers, prune_border);
 		self.prune_border = prune_border;
 	}
@@ -527,6 +545,7 @@ impl<P: HeadersSyncPipeline> QueuedHeaders<P> {
 		self.ready.clear();
 		self.incomplete.clear();
 		self.submitted.clear();
+		self.synced_children.clear();
 		self.known_headers.clear();
 		self.best_synced_number = Zero::zero();
 		self.prune_border = Zero::zero();
@@ -568,6 +587,7 @@ impl<P: HeadersSyncPipeline> QueuedHeaders<P> {
 		// queues
 		let mut current = *id;
 		let mut id_processed = false;
+		let mut previous_current = None;
 		loop {
 			let header = match self.status(&current) {
 				HeaderStatus::Unknown => break,
@@ -582,8 +602,42 @@ impl<P: HeadersSyncPipeline> QueuedHeaders<P> {
 			}
 			.expect("header has a given status; given queue has the header; qed");
 
+			// remember ids of all the children of the current header
+			let synced_children_entry = self
+				.synced_children
+				.entry(current.0)
+				.or_default()
+				.entry(current.1)
+				.or_default();
+			let all_queues = [
+				&self.maybe_orphan,
+				&self.orphan,
+				&self.maybe_extra,
+				&self.extra,
+				&self.ready,
+				&self.incomplete,
+				&self.submitted,
+			];
+			for queue in &all_queues {
+				let children_from_queue = queue
+					.get(&(current.0 + One::one()))
+					.map(|potential_children| {
+						potential_children
+							.values()
+							.filter(|potential_child| potential_child.header().parent_id() == current)
+							.map(|child| child.id())
+							.collect::<Vec<_>>()
+					})
+					.unwrap_or_default();
+				synced_children_entry.extend(children_from_queue);
+			}
+			if let Some(previous_current) = previous_current {
+				synced_children_entry.insert(previous_current);
+			}
+
 			set_header_status::<P>(&mut self.known_headers, &current, HeaderStatus::Synced);
 
+			previous_current = Some(current);
 			current = header.parent_id();
 			id_processed = true;
 		}
@@ -706,6 +760,35 @@ fn move_header_descendants<P: HeadersSyncPipeline>(
 	}
 }
 
+/// Selects (recursive) all synced children of given header.
+fn select_synced_children<P: HeadersSyncPipeline>(
+	synced_children: &SyncedChildren<P>,
+	id: &HeaderIdOf<P>,
+) -> Vec<HeaderIdOf<P>> {
+	let mut result = Vec::new();
+	let mut current_parents = HashSet::new();
+	current_parents.insert(*id);
+
+	while !current_parents.is_empty() {
+		let mut next_parents = HashSet::new();
+		for current_parent in &current_parents {
+			let current_parent_synced_children = synced_children
+				.get(&current_parent.0)
+				.and_then(|by_number_entry| by_number_entry.get(&current_parent.1));
+			if let Some(current_parent_synced_children) = current_parent_synced_children {
+				for current_parent_synced_child in current_parent_synced_children {
+					result.push(*current_parent_synced_child);
+					next_parents.insert(*current_parent_synced_child);
+				}
+			}
+		}
+
+		let _ = std::mem::replace(&mut current_parents, next_parents);
+	}
+
+	result
+}
+
 /// Return oldest header from the queue.
 fn oldest_header<P: HeadersSyncPipeline>(queue: &HeadersQueue<P>) -> Option<&QueuedHeader<P>> {
 	queue.values().flat_map(|h| h.values()).next()
@@ -1050,6 +1133,37 @@ pub(crate) mod tests {
 			.known_headers
 			.values()
 			.all(|s| s.values().all(|s| *s == HeaderStatus::Synced)));
+
+		// children of synced headers are stored
+		assert_eq!(
+			vec![id(97)],
+			queue.synced_children[&96][&hash(96)]
+				.iter()
+				.cloned()
+				.collect::<Vec<_>>()
+		);
+		assert_eq!(
+			vec![id(98)],
+			queue.synced_children[&97][&hash(97)]
+				.iter()
+				.cloned()
+				.collect::<Vec<_>>()
+		);
+		assert_eq!(
+			vec![id(99)],
+			queue.synced_children[&98][&hash(98)]
+				.iter()
+				.cloned()
+				.collect::<Vec<_>>()
+		);
+		assert_eq!(
+			vec![id(100)],
+			queue.synced_children[&99][&hash(99)]
+				.iter()
+				.cloned()
+				.collect::<Vec<_>>()
+		);
+		assert_eq!(0, queue.synced_children[&100][&hash(100)].len());
 	}
 
 	#[test]
@@ -1463,6 +1577,16 @@ pub(crate) mod tests {
 			.or_default()
 			.insert(hash(100), HeaderStatus::Ready);
 		queue.ready.entry(100).or_default().insert(hash(100), header(100));
+		queue
+			.synced_children
+			.entry(100)
+			.or_default()
+			.insert(hash(100), vec![id(101)].into_iter().collect());
+		queue
+			.synced_children
+			.entry(102)
+			.or_default()
+			.insert(hash(102), vec![id(102)].into_iter().collect());
 
 		queue.prune(102);
 
@@ -1472,6 +1596,7 @@ pub(crate) mod tests {
 		assert_eq!(queue.orphan.len(), 1);
 		assert_eq!(queue.maybe_orphan.len(), 1);
 		assert_eq!(queue.incomplete.len(), 1);
+		assert_eq!(queue.synced_children.len(), 1);
 		assert_eq!(queue.known_headers.len(), 4);
 
 		queue.prune(110);
@@ -1482,6 +1607,7 @@ pub(crate) mod tests {
 		assert_eq!(queue.orphan.len(), 0);
 		assert_eq!(queue.maybe_orphan.len(), 0);
 		assert_eq!(queue.incomplete.len(), 0);
+		assert_eq!(queue.synced_children.len(), 0);
 		assert_eq!(queue.known_headers.len(), 0);
 
 		queue.header_response(header(109).header().clone());
@@ -1537,4 +1663,47 @@ pub(crate) mod tests {
 		assert_eq!(queue.status(&id(103)), HeaderStatus::Incomplete);
 		assert_eq!(queue.status(&id(104)), HeaderStatus::Incomplete);
 	}
+
+	#[test]
+	fn incomplete_headers_response_moves_synced_headers() {
+		let mut queue = QueuedHeaders::<TestHeadersSyncPipeline>::default();
+
+		// we have submitted two headers - 100 and 101. 102 is ready
+		queue.submitted.entry(100).or_default().insert(hash(100), header(100));
+		queue.submitted.entry(101).or_default().insert(hash(101), header(101));
+		queue.ready.entry(102).or_default().insert(hash(102), header(102));
+		queue
+			.known_headers
+			.entry(100)
+			.or_default()
+			.insert(hash(100), HeaderStatus::Submitted);
+		queue
+			.known_headers
+			.entry(101)
+			.or_default()
+			.insert(hash(101), HeaderStatus::Submitted);
+		queue
+			.known_headers
+			.entry(102)
+			.or_default()
+			.insert(hash(102), HeaderStatus::Ready);
+
+		// both headers are accepted
+		queue.target_best_header_response(&id(101));
+
+		// but header 100 is incomplete
+		queue.incomplete_headers_response(vec![id(100)].into_iter().collect());
+		assert_eq!(queue.status(&id(100)), HeaderStatus::Synced);
+		assert_eq!(queue.status(&id(101)), HeaderStatus::Synced);
+		assert_eq!(queue.status(&id(102)), HeaderStatus::Incomplete);
+		assert!(queue.incomplete_headers.contains_key(&id(100)));
+		assert!(queue.incomplete[&102].contains_key(&hash(102)));
+
+		// when header 100 is completed, 101 is synced and 102 is ready
+		queue.incomplete_headers_response(HashSet::new());
+		assert_eq!(queue.status(&id(100)), HeaderStatus::Synced);
+		assert_eq!(queue.status(&id(101)), HeaderStatus::Synced);
+		assert_eq!(queue.status(&id(102)), HeaderStatus::Ready);
+		assert!(queue.ready[&102].contains_key(&hash(102)));
+	}
 }

bridges/relays/headers-relay/src/sync_loop.rs

@@ -277,7 +277,7 @@ pub fn run<P: HeadersSyncPipeline, TC: TargetClient<P>>(
 						},
 						&mut target_go_offline_future,
 						|delay| async_std::task::sleep(delay),
-						|| format!("Error retrieving best known header from {} node", P::TARGET_NAME),
+						|| format!("Error retrieving best known {} header from {} node", P::SOURCE_NAME, P::TARGET_NAME),
 					).is_ok();
 				},
 				incomplete_headers_ids = target_incomplete_headers_future => {

bridges/relays/headers-relay/src/sync_types.rs

@@ -43,7 +43,7 @@ pub enum HeaderStatus {
 }
 
 /// Headers synchronization pipeline.
-pub trait HeadersSyncPipeline: Clone + Copy + Send + Sync {
+pub trait HeadersSyncPipeline: Clone + Send + Sync {
 	/// Name of the headers source.
 	const SOURCE_NAME: &'static str;
 	/// Name of the headers target.

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

@@ -60,12 +60,18 @@ impl From<millau_runtime::Header> for SyncHeader {
 	}
 }
 
+impl From<SyncHeader> for millau_runtime::Header {
+	fn from(header: SyncHeader) -> Self {
+		header.0
+	}
+}
+
 impl SourceHeader<millau_runtime::Hash, millau_runtime::BlockNumber> for SyncHeader {
 	fn id(&self) -> HeaderId {
 		relay_utils::HeaderId(*self.number(), self.hash())
 	}
 
 	fn parent_id(&self) -> HeaderId {
-		relay_utils::HeaderId(*self.number(), *self.parent_hash())
+		relay_utils::HeaderId(*self.number() - 1, *self.parent_hash())
 	}
 }

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

@@ -25,6 +25,8 @@ use sp_runtime::{
 	traits::{Header as HeaderT, IdentifyAccount},
 };
 
+pub use rialto_runtime::BridgeMillauCall;
+
 /// Rialto header id.
 pub type HeaderId = relay_utils::HeaderId<rialto_runtime::Hash, rialto_runtime::BlockNumber>;
 

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

@@ -33,6 +33,9 @@ const SUB_API_GRANDPA_AUTHORITIES: &str = "GrandpaApi_grandpa_authorities";
 pub type OpaqueGrandpaAuthoritiesSet = Vec<u8>;
 
 /// Substrate client type.
+///
+/// Cloning Client is a cheap operation.
+#[derive(Clone)]
 pub struct Client<C: Chain> {
 	/// Substrate RPC client.
 	client: RpcClient,

bridges/relays/substrate/Cargo.toml

@@ -16,6 +16,7 @@ structopt = "0.3"
 
 # Bridge dependencies
 
+bp-millau = { path = "../../primitives/millau" }
 bp-rialto = { path = "../../primitives/rialto" }
 headers-relay = { path = "../headers-relay" }
 messages-relay = { path = "../messages-relay" }
@@ -24,6 +25,7 @@ relay-rialto-client = { path = "../rialto-client" }
 relay-substrate-client = { path = "../substrate-client" }
 relay-utils = { path = "../utils" }
 
-# Substrate dependencies
+# Substrate Dependencies
 
+sp-core = "2.0"
 sp-runtime = "2.0"

bridges/relays/substrate/src/headers_target.rs

@@ -0,0 +1,168 @@
+// Copyright 2019-2020 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/>.
+
+//! Substrate client as Substrate headers target. The chain we connect to should have
+//! runtime that implements `<BridgedChainName>HeaderApi` to allow bridging with
+//! <BridgedName> chain.
+
+use async_trait::async_trait;
+use codec::{Decode, Encode};
+use futures::TryFutureExt;
+use headers_relay::{
+	sync_loop::TargetClient,
+	sync_types::{HeaderIdOf, HeadersSyncPipeline, QueuedHeader, SubmittedHeaders},
+};
+use relay_substrate_client::{Chain, Client, Error as SubstrateError};
+use relay_utils::HeaderId;
+use sp_core::Bytes;
+use sp_runtime::{DeserializeOwned, Justification};
+use std::collections::HashSet;
+
+/// Headers sync pipeline for Substrate <-> Substrate relays.
+#[async_trait]
+pub trait SubstrateHeadersSyncPipeline: HeadersSyncPipeline {
+	/// Name of the `best_block` runtime method.
+	const BEST_BLOCK_METHOD: &'static str;
+	/// Name of the `is_known_block` runtime method.
+	const IS_KNOWN_BLOCK_METHOD: &'static str;
+	/// Name of the `incomplete_headers` runtime method.
+	const INCOMPLETE_HEADERS_METHOD: &'static str;
+
+	/// Signed transaction type.
+	type SignedTransaction: Send + Sync + Encode;
+
+	/// Make submit header transaction.
+	async fn make_submit_header_transaction(
+		&self,
+		header: QueuedHeader<Self>,
+	) -> Result<Self::SignedTransaction, SubstrateError>;
+
+	/// Make completion transaction for the header.
+	async fn make_complete_header_transaction(
+		&self,
+		id: HeaderIdOf<Self>,
+		completion: Justification,
+	) -> Result<Self::SignedTransaction, SubstrateError>;
+}
+
+/// Substrate client as Substrate headers target.
+pub struct SubstrateHeadersTarget<C: Chain, P> {
+	client: Client<C>,
+	pipeline: P,
+}
+
+impl<C: Chain, P> SubstrateHeadersTarget<C, P> {
+	/// Create new Substrate headers target.
+	pub fn new(client: Client<C>, pipeline: P) -> Self {
+		SubstrateHeadersTarget { client, pipeline }
+	}
+}
+
+#[async_trait]
+impl<C, P> TargetClient<P> for SubstrateHeadersTarget<C, P>
+where
+	C: Chain,
+	C::Header: DeserializeOwned,
+	C::Index: DeserializeOwned,
+	P::Number: Decode,
+	P::Hash: Decode + Encode,
+	P: SubstrateHeadersSyncPipeline<Completion = Justification, Extra = ()>,
+{
+	type Error = SubstrateError;
+
+	async fn best_header_id(&self) -> Result<HeaderIdOf<P>, Self::Error> {
+		let call = P::BEST_BLOCK_METHOD.into();
+		let data = Bytes(Vec::new());
+
+		let encoded_response = self.client.state_call(call, data, None).await?;
+		let decoded_response: (P::Number, P::Hash) =
+			Decode::decode(&mut &encoded_response.0[..]).map_err(SubstrateError::ResponseParseFailed)?;
+
+		let best_header_id = HeaderId(decoded_response.0, decoded_response.1);
+		Ok(best_header_id)
+	}
+
+	async fn is_known_header(&self, id: HeaderIdOf<P>) -> Result<(HeaderIdOf<P>, bool), Self::Error> {
+		let call = P::IS_KNOWN_BLOCK_METHOD.into();
+		let data = Bytes(id.1.encode());
+
+		let encoded_response = self.client.state_call(call, data, None).await?;
+		let is_known_block: bool =
+			Decode::decode(&mut &encoded_response.0[..]).map_err(SubstrateError::ResponseParseFailed)?;
+
+		Ok((id, is_known_block))
+	}
+
+	async fn submit_headers(&self, mut headers: Vec<QueuedHeader<P>>) -> SubmittedHeaders<HeaderIdOf<P>, Self::Error> {
+		debug_assert_eq!(
+			headers.len(),
+			1,
+			"Substrate pallet only supports single header / transaction"
+		);
+
+		let header = headers.remove(0);
+		let id = header.id();
+		let submit_transaction_result = self
+			.pipeline
+			.make_submit_header_transaction(header)
+			.and_then(|tx| self.client.submit_extrinsic(Bytes(tx.encode())))
+			.await;
+
+		match submit_transaction_result {
+			Ok(_) => SubmittedHeaders {
+				submitted: vec![id],
+				incomplete: Vec::new(),
+				rejected: Vec::new(),
+				fatal_error: None,
+			},
+			Err(error) => SubmittedHeaders {
+				submitted: Vec::new(),
+				incomplete: Vec::new(),
+				rejected: vec![id],
+				fatal_error: Some(error),
+			},
+		}
+	}
+
+	async fn incomplete_headers_ids(&self) -> Result<HashSet<HeaderIdOf<P>>, Self::Error> {
+		let call = P::INCOMPLETE_HEADERS_METHOD.into();
+		let data = Bytes(Vec::new());
+
+		let encoded_response = self.client.state_call(call, data, None).await?;
+		let decoded_response: Vec<(P::Number, P::Hash)> =
+			Decode::decode(&mut &encoded_response.0[..]).map_err(SubstrateError::ResponseParseFailed)?;
+
+		let incomplete_headers = decoded_response
+			.into_iter()
+			.map(|(number, hash)| HeaderId(number, hash))
+			.collect();
+		Ok(incomplete_headers)
+	}
+
+	async fn complete_header(
+		&self,
+		id: HeaderIdOf<P>,
+		completion: Justification,
+	) -> Result<HeaderIdOf<P>, Self::Error> {
+		let tx = self.pipeline.make_complete_header_transaction(id, completion).await?;
+		self.client.submit_extrinsic(Bytes(tx.encode())).await?;
+		Ok(id)
+	}
+
+	async fn requires_extra(&self, header: QueuedHeader<P>) -> Result<(HeaderIdOf<P>, bool), Self::Error> {
+		Ok((header.id(), false))
+	}
+}

bridges/relays/substrate/src/main.rs

@@ -28,6 +28,7 @@ pub type MillauClient = relay_substrate_client::Client<relay_millau_client::Mill
 pub type RialtoClient = relay_substrate_client::Client<relay_rialto_client::Rialto>;
 
 mod cli;
+mod headers_target;
 mod millau_headers_to_rialto;
 
 fn main() {

bridges/relays/substrate/src/millau_headers_to_rialto.rs

@@ -16,24 +16,33 @@
 
 //! Millau-to-Rialto headers sync entrypoint.
 
-use crate::{MillauClient, RialtoClient};
+use crate::{
+	headers_target::{SubstrateHeadersSyncPipeline, SubstrateHeadersTarget},
+	MillauClient, RialtoClient,
+};
 
 use async_trait::async_trait;
+use bp_millau::{BEST_MILLAU_BLOCK_METHOD, INCOMPLETE_MILLAU_HEADERS_METHOD, IS_KNOWN_MILLAU_BLOCK_METHOD};
 use codec::Encode;
 use headers_relay::{
 	sync::{HeadersSyncParams, TargetTransactionMode},
-	sync_loop::TargetClient,
+	sync_types::{HeadersSyncPipeline, QueuedHeader},
-	sync_types::{HeadersSyncPipeline, QueuedHeader, SubmittedHeaders},
 };
 use relay_millau_client::{HeaderId as MillauHeaderId, Millau, SyncHeader as MillauSyncHeader};
-use relay_rialto_client::SigningParams as RialtoSigningParams;
+use relay_rialto_client::{BridgeMillauCall, Rialto, SigningParams as RialtoSigningParams};
-use relay_substrate_client::{headers_source::HeadersSource, BlockNumberOf, Error as SubstrateError, HashOf};
+use relay_substrate_client::{
+	headers_source::HeadersSource, BlockNumberOf, Error as SubstrateError, HashOf, TransactionSignScheme,
+};
+use sp_core::Pair;
 use sp_runtime::Justification;
-use std::{collections::HashSet, time::Duration};
+use std::time::Duration;
 
 /// Millau-to-Rialto headers pipeline.
-#[derive(Debug, Clone, Copy)]
+#[derive(Debug, Clone)]
-struct MillauHeadersToRialto;
+struct MillauHeadersToRialto {
+	client: RialtoClient,
+	sign: RialtoSigningParams,
+}
 
 impl HeadersSyncPipeline for MillauHeadersToRialto {
 	const SOURCE_NAME: &'static str = "Millau";
@@ -50,6 +59,38 @@ impl HeadersSyncPipeline for MillauHeadersToRialto {
 	}
 }
 
+#[async_trait]
+impl SubstrateHeadersSyncPipeline for MillauHeadersToRialto {
+	const BEST_BLOCK_METHOD: &'static str = BEST_MILLAU_BLOCK_METHOD;
+	const IS_KNOWN_BLOCK_METHOD: &'static str = IS_KNOWN_MILLAU_BLOCK_METHOD;
+	const INCOMPLETE_HEADERS_METHOD: &'static str = INCOMPLETE_MILLAU_HEADERS_METHOD;
+
+	type SignedTransaction = <Rialto as TransactionSignScheme>::SignedTransaction;
+
+	async fn make_submit_header_transaction(
+		&self,
+		header: QueuedMillauHeader,
+	) -> Result<Self::SignedTransaction, SubstrateError> {
+		let account_id = self.sign.signer.public().as_array_ref().clone().into();
+		let nonce = self.client.next_account_index(account_id).await?;
+		let call = BridgeMillauCall::import_signed_header(header.header().clone().into()).into();
+		let transaction = Rialto::sign_transaction(&self.client, &self.sign.signer, nonce, call);
+		Ok(transaction)
+	}
+
+	async fn make_complete_header_transaction(
+		&self,
+		id: MillauHeaderId,
+		completion: Justification,
+	) -> Result<Self::SignedTransaction, SubstrateError> {
+		let account_id = self.sign.signer.public().as_array_ref().clone().into();
+		let nonce = self.client.next_account_index(account_id).await?;
+		let call = BridgeMillauCall::finalize_header(id.1, completion).into();
+		let transaction = Rialto::sign_transaction(&self.client, &self.sign.signer, nonce, call);
+		Ok(transaction)
+	}
+}
+
 /// Millau header in-the-queue.
 type QueuedMillauHeader = QueuedHeader<MillauHeadersToRialto>;
 
@@ -57,44 +98,7 @@ type QueuedMillauHeader = QueuedHeader<MillauHeadersToRialto>;
 type MillauSourceClient = HeadersSource<Millau, MillauHeadersToRialto>;
 
 /// Rialto node as headers target.
-struct RialtoTargetClient {
+type RialtoTargetClient = SubstrateHeadersTarget<Rialto, MillauHeadersToRialto>;
-	_client: RialtoClient,
-	_sign: RialtoSigningParams,
-}
-
-#[async_trait]
-impl TargetClient<MillauHeadersToRialto> for RialtoTargetClient {
-	type Error = SubstrateError;
-
-	async fn best_header_id(&self) -> Result<MillauHeaderId, Self::Error> {
-		unimplemented!("https://github.com/paritytech/parity-bridges-common/issues/209")
-	}
-
-	async fn is_known_header(&self, _id: MillauHeaderId) -> Result<(MillauHeaderId, bool), Self::Error> {
-		unimplemented!("https://github.com/paritytech/parity-bridges-common/issues/209")
-	}
-
-	async fn submit_headers(&self, _headers: Vec<QueuedMillauHeader>) -> SubmittedHeaders<MillauHeaderId, Self::Error> {
-		unimplemented!("https://github.com/paritytech/parity-bridges-common/issues/209")
-	}
-
-	async fn incomplete_headers_ids(&self) -> Result<HashSet<MillauHeaderId>, Self::Error> {
-		unimplemented!("https://github.com/paritytech/parity-bridges-common/issues/209")
-	}
-
-	#[allow(clippy::unit_arg)]
-	async fn complete_header(
-		&self,
-		_id: MillauHeaderId,
-		_completion: Justification,
-	) -> Result<MillauHeaderId, Self::Error> {
-		unimplemented!("https://github.com/paritytech/parity-bridges-common/issues/209")
-	}
-
-	async fn requires_extra(&self, _header: QueuedMillauHeader) -> Result<(MillauHeaderId, bool), Self::Error> {
-		unimplemented!("https://github.com/paritytech/parity-bridges-common/issues/209")
-	}
-}
 
 /// Run Millau-to-Rialto headers sync.
 pub fn run(
@@ -107,8 +111,8 @@ pub fn run(
 	let rialto_tick = Duration::from_secs(5);
 	let sync_params = HeadersSyncParams {
 		max_future_headers_to_download: 32,
-		max_headers_in_submitted_status: 1024,
+		max_headers_in_submitted_status: 8,
-		max_headers_in_single_submit: 8,
+		max_headers_in_single_submit: 1,
 		max_headers_size_in_single_submit: 1024 * 1024,
 		prune_depth: 256,
 		target_tx_mode: TargetTransactionMode::Signed,
@@ -117,10 +121,13 @@ pub fn run(
 	headers_relay::sync_loop::run(
 		MillauSourceClient::new(millau_client),
 		millau_tick,
-		RialtoTargetClient {
+		RialtoTargetClient::new(
-			_client: rialto_client,
+			rialto_client.clone(),
-			_sign: rialto_sign,
+			MillauHeadersToRialto {
-		},
+				client: rialto_client,
+				sign: rialto_sign,
+			},
+		),
 		rialto_tick,
 		sync_params,
 		metrics_params,