FinalityEngine in substrate relay (#1374)

* introduce FinalityEngine in relay code * add FinalityEngine to relay * spelling * fix test compilation * Update relays/lib-substrate-relay/src/finality/source.rs Co-authored-by: Adrian Catangiu <adrian@parity.io> Co-authored-by: Adrian Catangiu <adrian@parity.io>
2026-05-31 02:51:01 +00:00 · 2022-04-14 12:05:57 +03:00
parent 6a4144e8f2
commit b3c8852bcf
23 changed files with 469 additions and 359 deletions
@@ -0,0 +1,121 @@
+// 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/>.
+
+//! Initialize Substrate -> Substrate finality bridge.
+//!
+//! Initialization is a transaction that calls `initialize()` function of the
+//! finality pallet (GRANDPA/BEEFY/...). This transaction brings initial header
+//! and authorities set from source to target chain. The finality sync starts
+//! with this header.
+
+use crate::{error::Error, finality::engine::Engine};
+
+use relay_substrate_client::{BlockNumberOf, Chain, Client, Error as SubstrateError, HashOf};
+use sp_core::Bytes;
+use sp_runtime::traits::Header as HeaderT;
+
+/// Submit headers-bridge initialization transaction.
+pub async fn initialize<E: Engine<SourceChain>, SourceChain: Chain, TargetChain: Chain, F>(
+	source_client: Client<SourceChain>,
+	target_client: Client<TargetChain>,
+	target_transactions_signer: TargetChain::AccountId,
+	prepare_initialize_transaction: F,
+) where
+	F: FnOnce(TargetChain::Index, E::InitializationData) -> Result<Bytes, SubstrateError>
+		+ Send
+		+ 'static,
+{
+	let result = do_initialize::<E, _, _, _>(
+		source_client,
+		target_client,
+		target_transactions_signer,
+		prepare_initialize_transaction,
+	)
+	.await;
+
+	match result {
+		Ok(Some(tx_hash)) => log::info!(
+			target: "bridge",
+			"Successfully submitted {}-headers bridge initialization transaction to {}: {:?}",
+			SourceChain::NAME,
+			TargetChain::NAME,
+			tx_hash,
+		),
+		Ok(None) => (),
+		Err(err) => log::error!(
+			target: "bridge",
+			"Failed to submit {}-headers bridge initialization transaction to {}: {:?}",
+			SourceChain::NAME,
+			TargetChain::NAME,
+			err,
+		),
+	}
+}
+
+/// Craft and submit initialization transaction, returning any error that may occur.
+async fn do_initialize<E: Engine<SourceChain>, SourceChain: Chain, TargetChain: Chain, F>(
+	source_client: Client<SourceChain>,
+	target_client: Client<TargetChain>,
+	target_transactions_signer: TargetChain::AccountId,
+	prepare_initialize_transaction: F,
+) -> Result<
+	Option<TargetChain::Hash>,
+	Error<SourceChain::Hash, <SourceChain::Header as HeaderT>::Number>,
+>
+where
+	F: FnOnce(TargetChain::Index, E::InitializationData) -> Result<Bytes, SubstrateError>
+		+ Send
+		+ 'static,
+{
+	let is_initialized = is_initialized::<E, SourceChain, TargetChain>(&target_client).await?;
+	if is_initialized {
+		log::info!(
+			target: "bridge",
+			"{}-headers bridge at {} is already initialized. Skipping",
+			SourceChain::NAME,
+			TargetChain::NAME,
+		);
+		return Ok(None)
+	}
+
+	let initialization_data = E::prepare_initialization_data(source_client).await?;
+	log::info!(
+		target: "bridge",
+		"Prepared initialization data for {}-headers bridge at {}: {:?}",
+		SourceChain::NAME,
+		TargetChain::NAME,
+		initialization_data,
+	);
+
+	let initialization_tx_hash = target_client
+		.submit_signed_extrinsic(target_transactions_signer, move |_, transaction_nonce| {
+			prepare_initialize_transaction(transaction_nonce, initialization_data)
+		})
+		.await
+		.map_err(|err| Error::SubmitTransaction(TargetChain::NAME, err))?;
+	Ok(Some(initialization_tx_hash))
+}
+
+/// Returns `Ok(true)` if bridge has already been initialized.
+async fn is_initialized<E: Engine<SourceChain>, SourceChain: Chain, TargetChain: Chain>(
+	target_client: &Client<TargetChain>,
+) -> Result<bool, Error<HashOf<SourceChain>, BlockNumberOf<SourceChain>>> {
+	Ok(target_client
+		.raw_storage_value(E::is_initialized_key(), None)
+		.await
+		.map_err(|err| Error::RetrieveBestFinalizedHeaderHash(SourceChain::NAME, err))?
+		.is_some())
+}