Finality loop refactoring (#2357)

bridges/relays/finality/src/mock.rs

@@ -0,0 +1,209 @@
+// 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/>.
+
+//! Tests for finality synchronization loop.
+
+#![cfg(test)]
+
+use crate::{
+	base::SourceClientBase,
+	finality_loop::{SourceClient, TargetClient},
+	FinalityPipeline, FinalitySyncPipeline, SourceHeader,
+};
+
+use async_trait::async_trait;
+use bp_header_chain::{FinalityProof, GrandpaConsensusLogReader};
+use futures::{Stream, StreamExt};
+use parking_lot::Mutex;
+use relay_utils::{
+	relay_loop::Client as RelayClient, HeaderId, MaybeConnectionError, TrackedTransactionStatus,
+	TransactionTracker,
+};
+use std::{collections::HashMap, pin::Pin, sync::Arc};
+
+type IsMandatory = bool;
+pub type TestNumber = u64;
+type TestHash = u64;
+
+#[derive(Clone, Debug)]
+pub struct TestTransactionTracker(pub TrackedTransactionStatus<HeaderId<TestHash, TestNumber>>);
+
+impl Default for TestTransactionTracker {
+	fn default() -> TestTransactionTracker {
+		TestTransactionTracker(TrackedTransactionStatus::Finalized(Default::default()))
+	}
+}
+
+#[async_trait]
+impl TransactionTracker for TestTransactionTracker {
+	type HeaderId = HeaderId<TestHash, TestNumber>;
+
+	async fn wait(self) -> TrackedTransactionStatus<HeaderId<TestHash, TestNumber>> {
+		self.0
+	}
+}
+
+#[derive(Debug, Clone)]
+pub enum TestError {
+	NonConnection,
+}
+
+impl MaybeConnectionError for TestError {
+	fn is_connection_error(&self) -> bool {
+		false
+	}
+}
+
+#[derive(Debug, Clone, PartialEq)]
+pub struct TestFinalitySyncPipeline;
+
+impl FinalityPipeline for TestFinalitySyncPipeline {
+	const SOURCE_NAME: &'static str = "TestSource";
+	const TARGET_NAME: &'static str = "TestTarget";
+
+	type Hash = TestHash;
+	type Number = TestNumber;
+	type FinalityProof = TestFinalityProof;
+}
+
+impl FinalitySyncPipeline for TestFinalitySyncPipeline {
+	type ConsensusLogReader = GrandpaConsensusLogReader<TestNumber>;
+	type Header = TestSourceHeader;
+}
+
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub struct TestSourceHeader(pub IsMandatory, pub TestNumber, pub TestHash);
+
+impl SourceHeader<TestHash, TestNumber, GrandpaConsensusLogReader<TestNumber>>
+	for TestSourceHeader
+{
+	fn hash(&self) -> TestHash {
+		self.2
+	}
+
+	fn number(&self) -> TestNumber {
+		self.1
+	}
+
+	fn is_mandatory(&self) -> bool {
+		self.0
+	}
+}
+
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub struct TestFinalityProof(pub TestNumber);
+
+impl FinalityProof<TestNumber> for TestFinalityProof {
+	fn target_header_number(&self) -> TestNumber {
+		self.0
+	}
+}
+
+#[derive(Debug, Clone, Default)]
+pub struct ClientsData {
+	pub source_best_block_number: TestNumber,
+	pub source_headers: HashMap<TestNumber, (TestSourceHeader, Option<TestFinalityProof>)>,
+	pub source_proofs: Vec<TestFinalityProof>,
+
+	pub target_best_block_id: HeaderId<TestHash, TestNumber>,
+	pub target_headers: Vec<(TestSourceHeader, TestFinalityProof)>,
+	pub target_transaction_tracker: TestTransactionTracker,
+}
+
+#[derive(Clone)]
+pub struct TestSourceClient {
+	pub on_method_call: Arc<dyn Fn(&mut ClientsData) + Send + Sync>,
+	pub data: Arc<Mutex<ClientsData>>,
+}
+
+#[async_trait]
+impl RelayClient for TestSourceClient {
+	type Error = TestError;
+
+	async fn reconnect(&mut self) -> Result<(), TestError> {
+		unreachable!()
+	}
+}
+
+#[async_trait]
+impl SourceClientBase<TestFinalitySyncPipeline> for TestSourceClient {
+	type FinalityProofsStream = Pin<Box<dyn Stream<Item = TestFinalityProof> + 'static + Send>>;
+
+	async fn finality_proofs(&self) -> Result<Self::FinalityProofsStream, TestError> {
+		let mut data = self.data.lock();
+		(self.on_method_call)(&mut data);
+		Ok(futures::stream::iter(data.source_proofs.clone()).boxed())
+	}
+}
+
+#[async_trait]
+impl SourceClient<TestFinalitySyncPipeline> for TestSourceClient {
+	async fn best_finalized_block_number(&self) -> Result<TestNumber, TestError> {
+		let mut data = self.data.lock();
+		(self.on_method_call)(&mut data);
+		Ok(data.source_best_block_number)
+	}
+
+	async fn header_and_finality_proof(
+		&self,
+		number: TestNumber,
+	) -> Result<(TestSourceHeader, Option<TestFinalityProof>), TestError> {
+		let mut data = self.data.lock();
+		(self.on_method_call)(&mut data);
+		data.source_headers.get(&number).cloned().ok_or(TestError::NonConnection)
+	}
+}
+
+#[derive(Clone)]
+pub struct TestTargetClient {
+	pub on_method_call: Arc<dyn Fn(&mut ClientsData) + Send + Sync>,
+	pub data: Arc<Mutex<ClientsData>>,
+}
+
+#[async_trait]
+impl RelayClient for TestTargetClient {
+	type Error = TestError;
+
+	async fn reconnect(&mut self) -> Result<(), TestError> {
+		unreachable!()
+	}
+}
+
+#[async_trait]
+impl TargetClient<TestFinalitySyncPipeline> for TestTargetClient {
+	type TransactionTracker = TestTransactionTracker;
+
+	async fn best_finalized_source_block_id(
+		&self,
+	) -> Result<HeaderId<TestHash, TestNumber>, TestError> {
+		let mut data = self.data.lock();
+		(self.on_method_call)(&mut data);
+		Ok(data.target_best_block_id)
+	}
+
+	async fn submit_finality_proof(
+		&self,
+		header: TestSourceHeader,
+		proof: TestFinalityProof,
+	) -> Result<TestTransactionTracker, TestError> {
+		let mut data = self.data.lock();
+		(self.on_method_call)(&mut data);
+		data.target_best_block_id = HeaderId(header.number(), header.hash());
+		data.target_headers.push((header, proof));
+		(self.on_method_call)(&mut data);
+		Ok(data.target_transaction_tracker.clone())
+	}
+}