Transactions resubmitter (#1083)

* resubmit transactions: start

* resubmit transactions: continue

* enable resubmitter in deployments

* clippy

* spellcheck

* Update relays/client-substrate/src/chain.rs

Co-authored-by: Tomasz Drwięga <tomusdrw@users.noreply.github.com>

* fix compilation

* fix compilation

Co-authored-by: Tomasz Drwięga <tomusdrw@users.noreply.github.com>

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

@@ -21,7 +21,8 @@ use crate::rpc::Substrate;
 use crate::{ConnectionParams, Error, HeaderIdOf, Result};
 
 use async_std::sync::{Arc, Mutex};
-use codec::Decode;
+use async_trait::async_trait;
+use codec::{Decode, Encode};
 use frame_system::AccountInfo;
 use futures::{SinkExt, StreamExt};
 use jsonrpsee_ws_client::{traits::SubscriptionClient, v2::params::JsonRpcParams, DeserializeOwned};
@@ -31,12 +32,16 @@ use pallet_balances::AccountData;
 use pallet_transaction_payment::InclusionFee;
 use relay_utils::{relay_loop::RECONNECT_DELAY, HeaderId};
 use sp_core::{storage::StorageKey, Bytes};
-use sp_runtime::traits::Header as HeaderT;
+use sp_runtime::{
+	traits::Header as HeaderT,
+	transaction_validity::{TransactionSource, TransactionValidity},
+};
 use sp_trie::StorageProof;
 use sp_version::RuntimeVersion;
 use std::{convert::TryFrom, future::Future};
 
 const SUB_API_GRANDPA_AUTHORITIES: &str = "GrandpaApi_grandpa_authorities";
+const SUB_API_TXPOOL_VALIDATE_TRANSACTION: &str = "TaggedTransactionQueue_validate_transaction";
 const MAX_SUBSCRIPTION_CAPACITY: usize = 4096;
 
 /// Opaque justifications subscription type.
@@ -63,6 +68,18 @@ pub struct Client<C: Chain> {
 	submit_signed_extrinsic_lock: Arc<Mutex<()>>,
 }
 
+#[async_trait]
+impl<C: Chain> relay_utils::relay_loop::Client for Client<C> {
+	type Error = Error;
+
+	async fn reconnect(&mut self) -> Result<()> {
+		let (tokio, client) = Self::build_client(self.params.clone()).await?;
+		self.tokio = tokio;
+		self.client = client;
+		Ok(())
+	}
+}
+
 impl<C: Chain> Clone for Client<C> {
 	fn clone(&self) -> Self {
 		Client {
@@ -125,14 +142,6 @@ impl<C: Chain> Client<C> {
 		})
 	}
 
-	/// Reopen client connection.
-	pub async fn reconnect(&mut self) -> Result<()> {
-		let (tokio, client) = Self::build_client(self.params.clone()).await?;
-		self.tokio = tokio;
-		self.client = client;
-		Ok(())
-	}
-
 	/// Build client to use in connection.
 	async fn build_client(params: ConnectionParams) -> Result<(Arc<tokio::runtime::Runtime>, Arc<RpcClient>)> {
 		let tokio = tokio::runtime::Runtime::new()?;
@@ -309,6 +318,33 @@ impl<C: Chain> Client<C> {
 		.await
 	}
 
+	/// Returns pending extrinsics from transaction pool.
+	pub async fn pending_extrinsics(&self) -> Result<Vec<Bytes>> {
+		self.jsonrpsee_execute(
+			move |client| async move { Ok(Substrate::<C>::author_pending_extrinsics(&*client).await?) },
+		)
+		.await
+	}
+
+	/// Validate transaction at given block state.
+	pub async fn validate_transaction<SignedTransaction: Encode + Send + 'static>(
+		&self,
+		at_block: C::Hash,
+		transaction: SignedTransaction,
+	) -> Result<TransactionValidity> {
+		self.jsonrpsee_execute(move |client| async move {
+			let call = SUB_API_TXPOOL_VALIDATE_TRANSACTION.to_string();
+			let data = Bytes((TransactionSource::External, transaction, at_block).encode());
+
+			let encoded_response = Substrate::<C>::state_call(&*client, call, data, Some(at_block)).await?;
+			let validity =
+				TransactionValidity::decode(&mut &encoded_response.0[..]).map_err(Error::ResponseParseFailed)?;
+
+			Ok(validity)
+		})
+		.await
+	}
+
 	/// Estimate fee that will be spent on given extrinsic.
 	pub async fn estimate_extrinsic_fee(&self, transaction: Bytes) -> Result<InclusionFee<C::Balance>> {
 		self.jsonrpsee_execute(move |client| async move {