fatxpool: ChainApi is now async (#8875)

[`ChainApi`](https://github.com/paritytech/polkadot-sdk/blob/488072d245763fb059743bf32eea2f48d84054b3/substrate/client/transaction-pool/src/graph/pool.rs#L65-L66)
is now `async_trait`,
[`validate_transaction`](https://github.com/paritytech/polkadot-sdk/blob/488072d245763fb059743bf32eea2f48d84054b3/substrate/client/transaction-pool/src/graph/pool.rs#L78)
and
[`block_body`](https://github.com/paritytech/polkadot-sdk/blob/488072d245763fb059743bf32eea2f48d84054b3/substrate/client/transaction-pool/src/graph/pool.rs#L112)
are now `async` methods. This is just cleanup - migrating from returning
`Future` to `async` method

---------

Co-authored-by: cmd[bot] <41898282+github-actions[bot]@users.noreply.github.com>

Author: 2 people

Cargo.lock

@@ -0,0 +1,7 @@
+title: '`fatxpool`: `ChainApi` is now async'
+doc:
+- audience: Node Dev
+  description: Internal `ChainApi` is now `async_trait`, `validate_transaction` and `block_body` are now `async` methods. This is just cleanup - migrating from returning `Future` to `async` method'.
+crates:
+- name: sc-transaction-pool
+  bump: major

prdoc/pr_8875.prdoc

@@ -16,13 +16,10 @@
 // You should have received a copy of the GNU General Public License
 // along with this program. If not, see <https://www.gnu.org/licenses/>.
 
-use criterion::{criterion_group, criterion_main, Criterion};
-
+use async_trait::async_trait;
 use codec::Encode;
-use futures::{
-	executor::block_on,
-	future::{ready, Ready},
-};
+use criterion::{criterion_group, criterion_main, Criterion};
+use futures::executor::block_on;
 use sc_transaction_pool::*;
 use sp_blockchain::HashAndNumber;
 use sp_crypto_hashing::blake2_256;
@@ -55,31 +52,30 @@ fn to_tag(nonce: u64, from: AccountId) -> Tag {
 	data.to_vec()
 }
 
+#[async_trait]
 impl ChainApi for TestApi {
 	type Block = Block;
 	type Error = sc_transaction_pool_api::error::Error;
-	type ValidationFuture = Ready<sc_transaction_pool_api::error::Result<TransactionValidity>>;
-	type BodyFuture = Ready<sc_transaction_pool_api::error::Result<Option<Vec<Extrinsic>>>>;
 
-	fn validate_transaction(
+	async fn validate_transaction(
 		&self,
 		at: <Self::Block as BlockT>::Hash,
 		_: TransactionSource,
 		uxt: Arc<<Self::Block as BlockT>::Extrinsic>,
 		_: ValidateTransactionPriority,
-	) -> Self::ValidationFuture {
+	) -> Result<TransactionValidity, Self::Error> {
 		let uxt = (*uxt).clone();
 		let transfer = TransferData::try_from(&uxt)
 			.expect("uxt is expected to be bench_call (carrying TransferData)");
 		let nonce = transfer.nonce;
 		let from = transfer.from;
 
 		match self.block_id_to_number(&BlockId::Hash(at)) {
-			Ok(Some(num)) if num > 5 => return ready(Ok(Err(InvalidTransaction::Stale.into()))),
+			Ok(Some(num)) if num > 5 => return Ok(Err(InvalidTransaction::Stale.into())),
 			_ => {},
 		}
 
-		ready(Ok(Ok(ValidTransaction {
+		Ok(Ok(ValidTransaction {
 			priority: 4,
 			requires: if nonce > 1 && self.nonce_dependant {
 				vec![to_tag(nonce - 1, from)]
@@ -89,15 +85,15 @@ impl ChainApi for TestApi {
 			provides: vec![to_tag(nonce, from)],
 			longevity: 10,
 			propagate: true,
-		})))
+		}))
 	}
 
 	fn validate_transaction_blocking(
 		&self,
 		_at: <Self::Block as BlockT>::Hash,
 		_source: TransactionSource,
 		_uxt: Arc<<Self::Block as BlockT>::Extrinsic>,
-	) -> sc_transaction_pool_api::error::Result<TransactionValidity> {
+	) -> Result<TransactionValidity, Self::Error> {
 		unimplemented!();
 	}
 
@@ -128,8 +124,11 @@ impl ChainApi for TestApi {
 		(blake2_256(&encoded).into(), encoded.len())
 	}
 
-	fn block_body(&self, _id: <Self::Block as BlockT>::Hash) -> Self::BodyFuture {
-		ready(Ok(None))
+	async fn block_body(
+		&self,
+		_id: <Self::Block as BlockT>::Hash,
+	) -> Result<Option<Vec<<Self::Block as BlockT>::Extrinsic>>, Self::Error> {
+		Ok(None)
 	}
 
 	fn block_header(

substrate/client/transaction-pool/benches/basics.rs

@@ -23,8 +23,9 @@ use crate::{
 	graph::ValidateTransactionPriority,
 	insert_and_log_throttled, LOG_TARGET, LOG_TARGET_STAT,
 };
+use async_trait::async_trait;
 use codec::Encode;
-use futures::future::{ready, Future, FutureExt, Ready};
+use futures::future::{Future, FutureExt};
 use prometheus_endpoint::Registry as PrometheusRegistry;
 use sc_client_api::{blockchain::HeaderBackend, BlockBackend};
 use sp_api::{ApiExt, ProvideRuntimeApi};
@@ -181,6 +182,7 @@ impl<Client, Block> FullChainApi<Client, Block> {
 	}
 }
 
+#[async_trait]
 impl<Client, Block> graph::ChainApi for FullChainApi<Client, Block>
 where
 	Block: BlockT,
@@ -194,21 +196,21 @@ where
 {
 	type Block = Block;
 	type Error = error::Error;
-	type ValidationFuture =
-		Pin<Box<dyn Future<Output = error::Result<TransactionValidity>> + Send>>;
-	type BodyFuture = Ready<error::Result<Option<Vec<<Self::Block as BlockT>::Extrinsic>>>>;
 
-	fn block_body(&self, hash: Block::Hash) -> Self::BodyFuture {
-		ready(self.client.block_body(hash).map_err(error::Error::from))
+	async fn block_body(
+		&self,
+		hash: Block::Hash,
+	) -> Result<Option<Vec<<Self::Block as BlockT>::Extrinsic>>, Self::Error> {
+		self.client.block_body(hash).map_err(error::Error::from)
 	}
 
-	fn validate_transaction(
+	async fn validate_transaction(
 		&self,
 		at: <Self::Block as BlockT>::Hash,
 		source: TransactionSource,
 		uxt: graph::ExtrinsicFor<Self>,
 		validation_priority: ValidateTransactionPriority,
-	) -> Self::ValidationFuture {
+	) -> Result<TransactionValidity, Self::Error> {
 		let start = Instant::now();
 		let (tx, rx) = oneshot::channel();
 		let client = self.client.clone();
@@ -228,39 +230,36 @@ where
 			};
 		let metrics = self.metrics.clone();
 
-		async move {
-			metrics.report(|m| m.validations_scheduled.inc());
-
-			{
-				validation_pool
-					.send(
-						async move {
-							let res = validate_transaction_blocking(&*client, at, source, uxt);
-							let _ = tx.send(res);
-							metrics.report(|m| m.validations_finished.inc());
-						}
-						.boxed(),
-					)
-					.await
-					.map_err(|e| Error::RuntimeApi(format!("Validation pool down: {:?}", e)))?;
-			}
+		metrics.report(|m| m.validations_scheduled.inc());
 
-			let validity = match rx.await {
-				Ok(r) => r,
-				Err(_) => Err(Error::RuntimeApi("Validation was canceled".into())),
-			};
+		{
+			validation_pool
+				.send(
+					async move {
+						let res = validate_transaction_blocking(&*client, at, source, uxt);
+						let _ = tx.send(res);
+						metrics.report(|m| m.validations_finished.inc());
+					}
+					.boxed(),
+				)
+				.await
+				.map_err(|e| Error::RuntimeApi(format!("Validation pool down: {:?}", e)))?;
+		}
 
-			insert_and_log_throttled!(
-				Level::DEBUG,
-				target:LOG_TARGET_STAT,
-				prefix:prefix,
-				stats,
-				start.elapsed().into()
-			);
+		let validity = match rx.await {
+			Ok(r) => r,
+			Err(_) => Err(Error::RuntimeApi("Validation was canceled".into())),
+		};
+
+		insert_and_log_throttled!(
+			Level::DEBUG,
+			target:LOG_TARGET_STAT,
+			prefix:prefix,
+			stats,
+			start.elapsed().into()
+		);
 
-			validity
-		}
-		.boxed()
+		validity
 	}
 
 	/// Validates a transaction by calling into the runtime.
@@ -271,21 +270,21 @@ where
 		at: Block::Hash,
 		source: TransactionSource,
 		uxt: graph::ExtrinsicFor<Self>,
-	) -> error::Result<TransactionValidity> {
+	) -> Result<TransactionValidity, Self::Error> {
 		validate_transaction_blocking(&*self.client, at, source, uxt)
 	}
 
 	fn block_id_to_number(
 		&self,
 		at: &BlockId<Self::Block>,
-	) -> error::Result<Option<graph::NumberFor<Self>>> {
+	) -> Result<Option<graph::NumberFor<Self>>, Self::Error> {
 		self.client.to_number(at).map_err(|e| Error::BlockIdConversion(e.to_string()))
 	}
 
 	fn block_id_to_hash(
 		&self,
 		at: &BlockId<Self::Block>,
-	) -> error::Result<Option<graph::BlockHash<Self>>> {
+	) -> Result<Option<graph::BlockHash<Self>>, Self::Error> {
 		self.client.to_hash(at).map_err(|e| Error::BlockIdConversion(e.to_string()))
 	}
 

substrate/client/transaction-pool/src/common/api.rs

@@ -22,6 +22,7 @@ use crate::{
 	graph::{BlockHash, ChainApi, ExtrinsicFor, NumberFor, RawExtrinsicFor},
 	ValidateTransactionPriority,
 };
+use async_trait::async_trait;
 use codec::Encode;
 use parking_lot::Mutex;
 use sc_transaction_pool_api::error;
@@ -69,20 +70,19 @@ impl TestApi {
 	}
 }
 
+#[async_trait]
 impl ChainApi for TestApi {
 	type Block = Block;
 	type Error = error::Error;
-	type ValidationFuture = futures::future::Ready<error::Result<TransactionValidity>>;
-	type BodyFuture = futures::future::Ready<error::Result<Option<Vec<Extrinsic>>>>;
 
 	/// Verify extrinsic at given block.
-	fn validate_transaction(
+	async fn validate_transaction(
 		&self,
 		at: <Self::Block as BlockT>::Hash,
 		_source: TransactionSource,
 		uxt: ExtrinsicFor<Self>,
 		_: ValidateTransactionPriority,
-	) -> Self::ValidationFuture {
+	) -> Result<TransactionValidity, Self::Error> {
 		let uxt = (*uxt).clone();
 		self.validation_requests.lock().push(uxt.clone());
 		let hash = self.hash_and_length(&uxt).0;
@@ -159,15 +159,15 @@ impl ChainApi for TestApi {
 			_ => unimplemented!(),
 		};
 
-		futures::future::ready(Ok(res))
+		Ok(res)
 	}
 
 	fn validate_transaction_blocking(
 		&self,
 		_at: <Self::Block as BlockT>::Hash,
 		_source: TransactionSource,
 		_uxt: Arc<<Self::Block as BlockT>::Extrinsic>,
-	) -> error::Result<TransactionValidity> {
+	) -> Result<TransactionValidity, Self::Error> {
 		unimplemented!();
 	}
 
@@ -202,8 +202,11 @@ impl ChainApi for TestApi {
 		(Hashing::hash(&encoded), len)
 	}
 
-	fn block_body(&self, _id: <Self::Block as BlockT>::Hash) -> Self::BodyFuture {
-		futures::future::ready(Ok(None))
+	async fn block_body(
+		&self,
+		_id: <Self::Block as BlockT>::Hash,
+	) -> Result<Option<Vec<<Self::Block as BlockT>::Extrinsic>>, Self::Error> {
+		Ok(None)
 	}
 
 	fn block_header(

substrate/client/transaction-pool/src/common/tests.rs

@@ -17,7 +17,8 @@
 // along with this program. If not, see <https://www.gnu.org/licenses/>.
 
 use crate::{common::tracing_log_xt::log_xt_trace, LOG_TARGET};
-use futures::{channel::mpsc::Receiver, Future};
+use async_trait::async_trait;
+use futures::channel::mpsc::Receiver;
 use indexmap::IndexMap;
 use sc_transaction_pool_api::error;
 use sp_blockchain::{HashAndNumber, TreeRoute};
@@ -74,27 +75,21 @@ pub enum ValidateTransactionPriority {
 }
 
 /// Concrete extrinsic validation and query logic.
+#[async_trait]
 pub trait ChainApi: Send + Sync {
 	/// Block type.
 	type Block: BlockT;
 	/// Error type.
 	type Error: From<error::Error> + error::IntoPoolError;
-	/// Validate transaction future.
-	type ValidationFuture: Future<Output = Result<TransactionValidity, Self::Error>> + Send + Unpin;
-	/// Body future (since block body might be remote)
-	type BodyFuture: Future<Output = Result<Option<Vec<<Self::Block as traits::Block>::Extrinsic>>, Self::Error>>
-		+ Unpin
-		+ Send
-		+ 'static;
 
 	/// Asynchronously verify extrinsic at given block.
-	fn validate_transaction(
+	async fn validate_transaction(
 		&self,
 		at: <Self::Block as BlockT>::Hash,
 		source: TransactionSource,
 		uxt: ExtrinsicFor<Self>,
 		validation_priority: ValidateTransactionPriority,
-	) -> Self::ValidationFuture;
+	) -> Result<TransactionValidity, Self::Error>;
 
 	/// Synchronously verify given extrinsic at given block.
 	///
@@ -123,7 +118,10 @@ pub trait ChainApi: Send + Sync {
 	fn hash_and_length(&self, uxt: &RawExtrinsicFor<Self>) -> (ExtrinsicHash<Self>, usize);
 
 	/// Returns a block body given the block.
-	fn block_body(&self, at: <Self::Block as BlockT>::Hash) -> Self::BodyFuture;
+	async fn block_body(
+		&self,
+		at: <Self::Block as BlockT>::Hash,
+	) -> Result<Option<Vec<<Self::Block as traits::Block>::Extrinsic>>, Self::Error>;
 
 	/// Returns a block header given the block id.
 	fn block_header(

substrate/client/transaction-pool/src/graph/pool.rs

@@ -15,6 +15,7 @@ workspace = true
 targets = ["x86_64-unknown-linux-gnu"]
 
 [dependencies]
+async-trait = { workspace = true }
 codec = { workspace = true, default-features = true }
 futures = { workspace = true }
 log = { workspace = true }