wait_for_all_actors_to_stop

syndicate-server/src/main.rs

@@ -198,5 +198,7 @@ async fn main() -> Result<(), Box<dyn std::error::Error>> {
         Ok(())
     }).await??;
 
+    wait_for_all_actors_to_stop(std::time::Duration::from_secs(2)).await;
+
     Ok(())
 }

syndicate/src/actor.rs

@@ -2005,6 +2005,47 @@ impl<F: Send + FnMut(&mut Activation) -> ActorResult> Entity<Synced> for F {
     }
 }
 
+async fn wait_loop(wait_time: time::Duration) {
+    let deadline = time::Instant::now() + wait_time;
+    while time::Instant::now() < deadline {
+        let remaining_count = ACTORS.read().len();
+        if remaining_count == 0 {
+            break;
+        }
+        tracing::debug!("Waiting for {} remaining actors to stop", remaining_count);
+        tokio::time::sleep(time::Duration::from_millis(100)).await;
+    }
+}
+
+pub async fn wait_for_all_actors_to_stop(wait_time: time::Duration) {
+    wait_loop(wait_time).await;
+    let remaining = ACTORS.read().clone();
+    if remaining.len() > 0 {
+        tracing::warn!("Some actors remain after {:?}:", wait_time);
+        for (name, actor) in remaining.into_values() {
+            let _entry = name.enter();
+            tracing::warn!(?actor, "still running, requesting shutdown");
+            let g = actor.state.lock();
+            if let ActorState::Running(state) = &*g {
+                state.shutdown();
+            }
+        }
+        wait_loop(wait_time).await;
+        let remaining = ACTORS.read().clone();
+        if remaining.len() > 0 {
+            tracing::error!("Some actors failed to stop after being explicitly shut down:");
+            for (name, actor) in remaining.into_values() {
+                let _entry = name.enter();
+                tracing::error!(?actor, "failed to stop");
+            }
+        } else {
+            tracing::debug!("All remaining actors have stopped.");
+        }
+    } else {
+        tracing::debug!("All remaining actors have stopped.");
+    }
+}
+
 /// A convenient Syndicate-enhanced variation on
 /// [`tracing::info_span`].
 ///