From 6aea07105a2617ebb7e2bbf03bd6b2d6f974af25 Mon Sep 17 00:00:00 2001
From: Miguel <migueloliveiradev@gmail.com>
Date: Thu, 25 Jul 2024 10:49:17 -0300
Subject: [PATCH] FatalError in EngineHandlerEvent  (#9800)

Co-authored-by: Matthias Seitz <matthias.seitz@outlook.de>
---
 crates/engine/tree/src/chain.rs  | 7 +++++++
 crates/engine/tree/src/engine.rs | 6 +++++-
 2 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/crates/engine/tree/src/chain.rs b/crates/engine/tree/src/chain.rs
index 10a19776fd..e77139d3e3 100644
--- a/crates/engine/tree/src/chain.rs
+++ b/crates/engine/tree/src/chain.rs
@@ -5,6 +5,7 @@ use std::{
     pin::Pin,
     task::{Context, Poll},
 };
+use tracing::*;
 
 /// The type that drives the chain forward.
 ///
@@ -121,6 +122,10 @@ where
                             // bubble up the event
                             return Poll::Ready(ChainEvent::Handler(ev));
                         }
+                        HandlerEvent::FatalError => {
+                            error!(target: "engine::tree", "Fatal error");
+                            return Poll::Ready(ChainEvent::FatalError)
+                        }
                     }
                 }
                 Poll::Pending => {
@@ -190,6 +195,8 @@ pub enum HandlerEvent<T> {
     BackfillAction(BackfillAction),
     /// Other event emitted by the handler
     Event(T),
+    // Fatal error
+    FatalError,
 }
 
 /// Internal events issued by the [`ChainOrchestrator`].
diff --git a/crates/engine/tree/src/engine.rs b/crates/engine/tree/src/engine.rs
index eeac5e5d75..bd4c220565 100644
--- a/crates/engine/tree/src/engine.rs
+++ b/crates/engine/tree/src/engine.rs
@@ -84,6 +84,7 @@ where
                                 // bubble up the event
                                 Poll::Ready(HandlerEvent::Event(ev))
                             }
+                            HandlerEvent::FatalError => Poll::Ready(HandlerEvent::FatalError),
                         }
                     }
                     RequestHandlerEvent::Download(req) => {
@@ -186,7 +187,10 @@ where
     }
 
     fn poll(&mut self, cx: &mut Context<'_>) -> Poll<RequestHandlerEvent<Self::Event>> {
-        let Some(ev) = ready!(self.from_tree.poll_recv(cx)) else { return Poll::Pending };
+        let Some(ev) = ready!(self.from_tree.poll_recv(cx)) else {
+            return Poll::Ready(RequestHandlerEvent::HandlerEvent(HandlerEvent::FatalError))
+        };
+
         let ev = match ev {
             EngineApiEvent::BeaconConsensus(ev) => {
                 RequestHandlerEvent::HandlerEvent(HandlerEvent::Event(ev))