From 70ed8c2c08c61044aea1b37d047ac5064c942d5a Mon Sep 17 00:00:00 2001
From: ShahakShama <70578257+ShahakShama@users.noreply.github.com>
Date: Mon, 30 Dec 2024 15:56:58 +0200
Subject: [PATCH] feat(papyrus_p2p_sync): p2p sync client and server return
 Never on ok (#2984)

---
 crates/papyrus_node/src/run.rs               |  2 +-
 crates/papyrus_p2p_sync/src/client/mod.rs    |  3 ++-
 crates/papyrus_p2p_sync/src/server/mod.rs    | 11 ++++++-----
 crates/starknet_state_sync/src/runner/mod.rs | 15 +++++++++------
 4 files changed, 18 insertions(+), 13 deletions(-)

diff --git a/crates/papyrus_node/src/run.rs b/crates/papyrus_node/src/run.rs
index ed9d81c948..d78b1e3ad2 100644
--- a/crates/papyrus_node/src/run.rs
+++ b/crates/papyrus_node/src/run.rs
@@ -306,7 +306,7 @@ async fn spawn_sync_client(
                 p2p_sync_client_channels,
                 futures::stream::pending().boxed(),
             );
-            tokio::spawn(async move { Ok(p2p_sync.run().await?) })
+            tokio::spawn(async move { Ok(p2p_sync.run().await.map(|_never| ())?) })
         }
     }
 }
diff --git a/crates/papyrus_p2p_sync/src/client/mod.rs b/crates/papyrus_p2p_sync/src/client/mod.rs
index 8a1a4e3d80..53646f748d 100644
--- a/crates/papyrus_p2p_sync/src/client/mod.rs
+++ b/crates/papyrus_p2p_sync/src/client/mod.rs
@@ -19,6 +19,7 @@ use std::time::Duration;
 
 use class::ClassStreamBuilder;
 use futures::channel::mpsc::{Receiver, SendError, Sender};
+use futures::never::Never;
 use futures::stream::BoxStream;
 use futures::{SinkExt as _, Stream};
 use header::HeaderStreamBuilder;
@@ -229,7 +230,7 @@ impl P2PSyncClient {
     }
 
     #[instrument(skip(self), level = "debug", err)]
-    pub async fn run(self) -> Result<(), P2PSyncClientError> {
+    pub async fn run(self) -> Result<Never, P2PSyncClientError> {
         info!("Starting P2P sync client");
 
         let InternalBlocksChannels {
diff --git a/crates/papyrus_p2p_sync/src/server/mod.rs b/crates/papyrus_p2p_sync/src/server/mod.rs
index 205a10239a..a350466a4a 100644
--- a/crates/papyrus_p2p_sync/src/server/mod.rs
+++ b/crates/papyrus_p2p_sync/src/server/mod.rs
@@ -1,5 +1,6 @@
 use std::fmt::Debug;
 
+use futures::never::Never;
 use futures::StreamExt;
 use papyrus_common::pending_classes::ApiContractClass;
 use papyrus_network::network_manager::{ServerQueryManager, SqmrServerReceiver};
@@ -107,7 +108,7 @@ pub struct P2PSyncServer {
 }
 
 impl P2PSyncServer {
-    pub async fn run(self) {
+    pub async fn run(self) -> Never {
         let P2PSyncServerChannels {
             mut header_receiver,
             mut state_diff_receiver,
@@ -135,14 +136,14 @@ impl P2PSyncServer {
                     );
                     register_query(self.storage_reader.clone(), server_query_manager);
                 }
-                mayber_server_query_manager = class_receiver.next() => {
-                    let server_query_manager = mayber_server_query_manager.expect(
+                maybe_server_query_manager = class_receiver.next() => {
+                    let server_query_manager = maybe_server_query_manager.expect(
                         "Class queries sender was unexpectedly dropped."
                     );
                     register_query(self.storage_reader.clone(), server_query_manager);
                 }
-                mayber_server_query_manager = event_receiver.next() => {
-                    let server_query_manager = mayber_server_query_manager.expect(
+                maybe_server_query_manager = event_receiver.next() => {
+                    let server_query_manager = maybe_server_query_manager.expect(
                         "Event queries sender was unexpectedly dropped."
                     );
                     register_query(self.storage_reader.clone(), server_query_manager);
diff --git a/crates/starknet_state_sync/src/runner/mod.rs b/crates/starknet_state_sync/src/runner/mod.rs
index edb6371fa8..ab2b080967 100644
--- a/crates/starknet_state_sync/src/runner/mod.rs
+++ b/crates/starknet_state_sync/src/runner/mod.rs
@@ -4,6 +4,7 @@ mod test;
 use async_trait::async_trait;
 use futures::channel::mpsc::Receiver;
 use futures::future::BoxFuture;
+use futures::never::Never;
 use futures::{FutureExt, StreamExt};
 use papyrus_network::network_manager::{self, NetworkError};
 use papyrus_p2p_sync::client::{P2PSyncClient, P2PSyncClientChannels, P2PSyncClientError};
@@ -21,8 +22,8 @@ use crate::config::StateSyncConfig;
 pub struct StateSyncRunner {
     network_future: BoxFuture<'static, Result<(), NetworkError>>,
     // TODO: change client and server to requester and responder respectively
-    p2p_sync_client_future: BoxFuture<'static, Result<(), P2PSyncClientError>>,
-    p2p_sync_server_future: BoxFuture<'static, ()>,
+    p2p_sync_client_future: BoxFuture<'static, Result<Never, P2PSyncClientError>>,
+    p2p_sync_server_future: BoxFuture<'static, Never>,
 }
 
 #[async_trait]
@@ -30,11 +31,13 @@ impl ComponentStarter for StateSyncRunner {
     async fn start(&mut self) -> Result<(), ComponentError> {
         tokio::select! {
             result = &mut self.network_future => {
-                return result.map_err(|_| ComponentError::InternalComponentError);
+                result.map_err(|_| ComponentError::InternalComponentError)
             }
-            result = &mut self.p2p_sync_client_future => return result.map_err(|_| ComponentError::InternalComponentError),
-            () = &mut self.p2p_sync_server_future => {
-                return Err(ComponentError::InternalComponentError);
+            result = &mut self.p2p_sync_client_future => {
+                result.map_err(|_| ComponentError::InternalComponentError).map(|_never| ())
+            }
+            _never = &mut self.p2p_sync_server_future => {
+                Err(ComponentError::InternalComponentError)
             }
         }
     }