TransactionInvalidationTracker (#1544)

* TransactionInvalidationTracker * TransacitonInvalidationTracker -> TransactionTracker * change sign_transaction method * clippy and spelling * removed comment * more transactiontracker tests * stalls_when_transaction_tracker_returns_error * remove test code * remove "impl TransactionTracker for ()" * enum TrackedTransactionStatus * test TransactionTracker in on_transaction_status * do_wait
2026-05-31 07:31:02 +00:00 · 2022-09-14 17:30:57 +03:00
parent 58fe2749d2
commit 70d6e91f20
8 changed files with 514 additions and 145 deletions
@@ -0,0 +1,322 @@
+// 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/>.
+
+//! Helper for tracking transaction invalidation events.
+
+use crate::{Chain, HashOf, Subscription, TransactionStatusOf};
+
+use async_trait::async_trait;
+use futures::{Stream, StreamExt};
+use relay_utils::TrackedTransactionStatus;
+use std::time::Duration;
+
+/// Substrate transaction tracker implementation.
+///
+/// Substrate node provides RPC API to submit and watch for transaction events. This way
+/// we may know when transaction is included into block, finalized or rejected. There are
+/// some edge cases, when we can't fully trust this mechanism - e.g. transaction may broadcasted
+/// and then dropped out of node transaction pool (some other cases are also possible - node
+/// restarts, connection lost, ...). Then we can't know for sure - what is currently happening
+/// with our transaction. Is the transaction really lost? Is it still alive on the chain network?
+///
+/// We have several options to handle such cases:
+///
+/// 1) hope that the transaction is still alive and wait for its mining until it is spoiled;
+///
+/// 2) assume that the transaction is lost and resubmit another transaction instantly;
+///
+/// 3) wait for some time (if transaction is mortal - then until block where it dies; if it is
+///    immortal - then for some time that we assume is long enough to mine it) and assume that
+///    it is lost.
+///
+/// This struct implements third option as it seems to be the most optimal.
+pub struct TransactionTracker<C: Chain> {
+	transaction_hash: HashOf<C>,
+	stall_timeout: Duration,
+	subscription: Subscription<TransactionStatusOf<C>>,
+}
+
+impl<C: Chain> TransactionTracker<C> {
+	/// Create transaction tracker.
+	pub fn new(
+		stall_timeout: Duration,
+		transaction_hash: HashOf<C>,
+		subscription: Subscription<TransactionStatusOf<C>>,
+	) -> Self {
+		Self { stall_timeout, transaction_hash, subscription }
+	}
+
+	/// Wait for final transaction status and return it along with last known internal invalidation
+	/// status.
+	async fn do_wait(self) -> (TrackedTransactionStatus, InvalidationStatus) {
+		let invalidation_status = watch_transaction_status::<C, _>(
+			self.transaction_hash,
+			self.subscription.into_stream(),
+		)
+		.await;
+		match invalidation_status {
+			InvalidationStatus::Finalized =>
+				(TrackedTransactionStatus::Finalized, invalidation_status),
+			InvalidationStatus::Invalid => (TrackedTransactionStatus::Lost, invalidation_status),
+			InvalidationStatus::Lost => {
+				async_std::task::sleep(self.stall_timeout).await;
+				// if someone is still watching for our transaction, then we're reporting
+				// an error here (which is treated as "transaction lost")
+				log::trace!(
+					target: "bridge",
+					"{} transaction {:?} is considered lost after timeout",
+					C::NAME,
+					self.transaction_hash,
+				);
+
+				(TrackedTransactionStatus::Lost, invalidation_status)
+			},
+		}
+	}
+}
+
+#[async_trait]
+impl<C: Chain> relay_utils::TransactionTracker for TransactionTracker<C> {
+	async fn wait(self) -> TrackedTransactionStatus {
+		self.do_wait().await.0
+	}
+}
+
+/// Transaction invalidation status.
+///
+/// Note that in places where the `TransactionTracker` is used, the finalization event will be
+/// ignored - relay loops are detecting the mining/finalization using their own
+/// techniques. That's why we're using `InvalidationStatus` here.
+#[derive(Debug, PartialEq)]
+enum InvalidationStatus {
+	/// Transaction has been included into block and finalized.
+	Finalized,
+	/// Transaction has been invalidated.
+	Invalid,
+	/// We have lost track of transaction status.
+	Lost,
+}
+
+/// Watch for transaction status until transaction is finalized or we lose track of its status.
+async fn watch_transaction_status<C: Chain, S: Stream<Item = TransactionStatusOf<C>>>(
+	transaction_hash: HashOf<C>,
+	subscription: S,
+) -> InvalidationStatus {
+	futures::pin_mut!(subscription);
+
+	loop {
+		match subscription.next().await {
+			Some(TransactionStatusOf::<C>::Finalized(block_hash)) => {
+				// the only "successful" outcome of this method is when the block with transaction
+				// has been finalized
+				log::trace!(
+					target: "bridge",
+					"{} transaction {:?} has been finalized at block: {:?}",
+					C::NAME,
+					transaction_hash,
+					block_hash,
+				);
+				return InvalidationStatus::Finalized
+			},
+			Some(TransactionStatusOf::<C>::Invalid) => {
+				// if node says that the transaction is invalid, there are still chances that
+				// it is not actually invalid - e.g. if the block where transaction has been
+				// revalidated is retracted and transaction (at some other node pool) becomes
+				// valid again on other fork. But let's assume that the chances of this event
+				// are almost zero - there's a lot of things that must happen for this to be the
+				// case.
+				log::trace!(
+					target: "bridge",
+					"{} transaction {:?} has been invalidated",
+					C::NAME,
+					transaction_hash,
+				);
+				return InvalidationStatus::Invalid
+			},
+			Some(TransactionStatusOf::<C>::Future) |
+			Some(TransactionStatusOf::<C>::Ready) |
+			Some(TransactionStatusOf::<C>::Broadcast(_)) => {
+				// nothing important (for us) has happened
+			},
+			Some(TransactionStatusOf::<C>::InBlock(block_hash)) => {
+				// TODO: read matching system event (ExtrinsicSuccess or ExtrinsicFailed), log it
+				// here and use it later (on finality) for reporting invalid transaction
+				// https://github.com/paritytech/parity-bridges-common/issues/1464
+				log::trace!(
+					target: "bridge",
+					"{} transaction {:?} has been included in block: {:?}",
+					C::NAME,
+					transaction_hash,
+					block_hash,
+				);
+			},
+			Some(TransactionStatusOf::<C>::Retracted(block_hash)) => {
+				log::trace!(
+					target: "bridge",
+					"{} transaction {:?} at block {:?} has been retracted",
+					C::NAME,
+					transaction_hash,
+					block_hash,
+				);
+			},
+			Some(TransactionStatusOf::<C>::FinalityTimeout(block_hash)) => {
+				// finality is lagging? let's wait a bit more and report a stall
+				log::trace!(
+					target: "bridge",
+					"{} transaction {:?} block {:?} has not been finalized for too long",
+					C::NAME,
+					transaction_hash,
+					block_hash,
+				);
+				return InvalidationStatus::Lost
+			},
+			Some(TransactionStatusOf::<C>::Usurped(new_transaction_hash)) => {
+				// this may be result of our transaction resubmitter work or some manual
+				// intervention. In both cases - let's start stall timeout, because the meaning
+				// of transaction may have changed
+				log::trace!(
+					target: "bridge",
+					"{} transaction {:?} has been usurped by new transaction: {:?}",
+					C::NAME,
+					transaction_hash,
+					new_transaction_hash,
+				);
+				return InvalidationStatus::Lost
+			},
+			Some(TransactionStatusOf::<C>::Dropped) => {
+				// the transaction has been removed from the pool because of its limits. Let's wait
+				// a bit and report a stall
+				log::trace!(
+					target: "bridge",
+					"{} transaction {:?} has been dropped from the pool",
+					C::NAME,
+					transaction_hash,
+				);
+				return InvalidationStatus::Lost
+			},
+			None => {
+				// the status of transaction is unknown to us (the subscription has been closed?).
+				// Let's wait a bit and report a stall
+				return InvalidationStatus::Lost
+			},
+		}
+	}
+}
+
+#[cfg(test)]
+mod tests {
+	use super::*;
+	use crate::test_chain::TestChain;
+	use futures::{FutureExt, SinkExt};
+	use sc_transaction_pool_api::TransactionStatus;
+
+	async fn on_transaction_status(
+		status: TransactionStatus<HashOf<TestChain>, HashOf<TestChain>>,
+	) -> Option<(TrackedTransactionStatus, InvalidationStatus)> {
+		let (mut sender, receiver) = futures::channel::mpsc::channel(1);
+		let tx_tracker = TransactionTracker::<TestChain>::new(
+			Duration::from_secs(0),
+			Default::default(),
+			Subscription(async_std::sync::Mutex::new(receiver)),
+		);
+
+		sender.send(Some(status)).await.unwrap();
+		tx_tracker.do_wait().now_or_never()
+	}
+
+	#[async_std::test]
+	async fn returns_finalized_on_finalized() {
+		assert_eq!(
+			on_transaction_status(TransactionStatus::Finalized(Default::default())).await,
+			Some((TrackedTransactionStatus::Finalized, InvalidationStatus::Finalized)),
+		);
+	}
+
+	#[async_std::test]
+	async fn returns_invalid_on_invalid() {
+		assert_eq!(
+			on_transaction_status(TransactionStatus::Invalid).await,
+			Some((TrackedTransactionStatus::Lost, InvalidationStatus::Invalid)),
+		);
+	}
+
+	#[async_std::test]
+	async fn waits_on_future() {
+		assert_eq!(on_transaction_status(TransactionStatus::Future).await, None,);
+	}
+
+	#[async_std::test]
+	async fn waits_on_ready() {
+		assert_eq!(on_transaction_status(TransactionStatus::Ready).await, None,);
+	}
+
+	#[async_std::test]
+	async fn waits_on_broadcast() {
+		assert_eq!(
+			on_transaction_status(TransactionStatus::Broadcast(Default::default())).await,
+			None,
+		);
+	}
+
+	#[async_std::test]
+	async fn waits_on_in_block() {
+		assert_eq!(
+			on_transaction_status(TransactionStatus::InBlock(Default::default())).await,
+			None,
+		);
+	}
+
+	#[async_std::test]
+	async fn waits_on_retracted() {
+		assert_eq!(
+			on_transaction_status(TransactionStatus::Retracted(Default::default())).await,
+			None,
+		);
+	}
+
+	#[async_std::test]
+	async fn lost_on_finality_timeout() {
+		assert_eq!(
+			on_transaction_status(TransactionStatus::FinalityTimeout(Default::default())).await,
+			Some((TrackedTransactionStatus::Lost, InvalidationStatus::Lost)),
+		);
+	}
+
+	#[async_std::test]
+	async fn lost_on_usurped() {
+		assert_eq!(
+			on_transaction_status(TransactionStatus::Usurped(Default::default())).await,
+			Some((TrackedTransactionStatus::Lost, InvalidationStatus::Lost)),
+		);
+	}
+
+	#[async_std::test]
+	async fn lost_on_dropped() {
+		assert_eq!(
+			on_transaction_status(TransactionStatus::Dropped).await,
+			Some((TrackedTransactionStatus::Lost, InvalidationStatus::Lost)),
+		);
+	}
+
+	#[async_std::test]
+	async fn lost_on_subscription_error() {
+		assert_eq!(
+			watch_transaction_status::<TestChain, _>(Default::default(), futures::stream::iter([]))
+				.now_or_never(),
+			Some(InvalidationStatus::Lost),
+		);
+	}
+}