Use OnceLock to initialize

Author: SozinM

crates/op-rbuilder/src/builders/flashblocks/payload.rs

@@ -45,7 +45,7 @@ use std::{
     ops::{Div, Rem},
     sync::{
         atomic::{AtomicU64, Ordering},
-        Arc, Mutex,
+        Arc, OnceLock,
     },
     time::Instant,
 };
@@ -121,8 +121,8 @@ pub struct OpPayloadBuilder<Pool, Client, BT> {
     #[allow(dead_code)]
     pub builder_tx: BT,
     /// Builder events handle to send BuiltPayload events
-    payload_builder_handle:
-        Arc<Mutex<Option<tokio::sync::broadcast::Sender<Events<OpEngineTypes>>>>>,
+    pub payload_builder_handle:
+        Arc<OnceLock<tokio::sync::broadcast::Sender<Events<OpEngineTypes>>>>,
 }
 
 impl<Pool, Client, BT> OpPayloadBuilder<Pool, Client, BT> {
@@ -134,7 +134,7 @@ impl<Pool, Client, BT> OpPayloadBuilder<Pool, Client, BT> {
         config: BuilderConfig<FlashblocksConfig>,
         builder_tx: BT,
         payload_builder_handle: Arc<
-            Mutex<Option<tokio::sync::broadcast::Sender<Events<OpEngineTypes>>>>,
+            OnceLock<tokio::sync::broadcast::Sender<Events<OpEngineTypes>>>,
         >,
     ) -> eyre::Result<Self> {
         let metrics = Arc::new(OpRBuilderMetrics::default());
@@ -625,8 +625,8 @@ where
     /// Sends built payload via payload builder handle broadcast channel to the engine
     pub fn send_payload_to_engine(&self, payload: OpBuiltPayload) {
         // Send built payload as create one
-        match self.payload_builder_handle.lock().as_deref() {
-            Ok(Some(handle)) => {
+        match self.payload_builder_handle.get() {
+            Some(handle) => {
                 let res = handle.send(Events::BuiltPayload(payload.clone()));
                 if let Err(e) = res {
                     error!(
@@ -635,13 +635,9 @@ where
                     );
                 }
             }
-            Ok(None) => {
+            None => {
                 error!(message = "Payload builder handle is not setup, skipping sending payload")
             }
-            Err(e) => error!(
-                message = "Failed to get access to payload builder handle",
-                error = ?e,
-            ),
         }
     }
 

crates/op-rbuilder/src/builders/flashblocks/service.rs

@@ -13,7 +13,7 @@ use reth_node_builder::{components::PayloadServiceBuilder, BuilderContext};
 use reth_optimism_evm::OpEvmConfig;
 use reth_payload_builder::{PayloadBuilderHandle, PayloadBuilderService};
 use reth_provider::CanonStateSubscriptions;
-use std::sync::{Arc, Mutex};
+use std::sync::Arc;
 
 pub struct FlashblocksServiceBuilder(pub BuilderConfig<FlashblocksConfig>);
 
@@ -29,16 +29,15 @@ impl FlashblocksServiceBuilder {
         Pool: PoolBounds,
         BT: BuilderTx + Unpin + Clone + Send + Sync + 'static,
     {
-        let handle = Arc::new(Mutex::new(None));
-        let payload_builder_handle = handle.clone();
+        let once_lock = Arc::new(std::sync::OnceLock::new());
 
         let payload_builder = OpPayloadBuilder::new(
             OpEvmConfig::optimism(ctx.chain_spec()),
             pool,
             ctx.provider().clone(),
             self.0.clone(),
             builder_tx,
-            handle,
+            once_lock.clone(),
         )?;
 
         let payload_job_config = BasicPayloadJobGeneratorConfig::default();
@@ -55,10 +54,9 @@ impl FlashblocksServiceBuilder {
         let (payload_service, payload_builder) =
             PayloadBuilderService::new(payload_generator, ctx.provider().canonical_state_stream());
 
-        payload_builder_handle
-            .lock()
-            .expect("store payload builder handle in mutex")
-            .replace(payload_service.payload_events_handle());
+        once_lock
+            .set(payload_service.payload_events_handle())
+            .map_err(|_| eyre::eyre!("Cannot initialize payload service handle"))?;
 
         ctx.task_executor()
             .spawn_critical("custom payload builder service", Box::pin(payload_service));

crates/op-rbuilder/src/primitives/reth/engine_api_builder.rs

@@ -23,7 +23,7 @@ use op_alloy_rpc_types_engine::{
     OpPayloadAttributes, ProtocolVersion, SuperchainSignal,
 };
 use reth::builder::NodeTypes;
-use reth_node_api::{EngineTypes, EngineApiValidator};
+use reth_node_api::{EngineApiValidator, EngineTypes};
 use reth_optimism_chainspec::OpChainSpec;
 use reth_optimism_rpc::OpEngineApiServer;
 use reth_rpc_api::IntoEngineApiRpcModule;

crates/op-rbuilder/src/revert_protection.rs

@@ -158,7 +158,9 @@ where
             .await
             .map_err(EthApiError::from)?;
 
-        let result = BundleResult { bundle_hash: outcome.hash };
+        let result = BundleResult {
+            bundle_hash: outcome.hash,
+        };
         Ok(result)
     }
 }