fix: call make_idle if the adapter is idle initially (#2278)

Before #2178, make_idle was called at
server startup if there have been no relevant transactions.

After #2178, make_idle is not called
anymore, meaning that the blockchain_manager and the connection_manager
will stay in a "non idle" state forever for subnets that don't run the
bitcoin adapter.

Author: mihailjianu1

rs/bitcoin/adapter/src/lib.rs

@@ -208,6 +208,15 @@ impl AdapterState {
             })
             .await;
     }
+
+    /// Returns whether the adapter is idle.
+    pub fn is_idle(&self) -> bool {
+        match *self.last_received_rx.borrow() {
+            Some(last) => last.elapsed().as_secs() >= self.idle_seconds,
+            // Nothing received yet still in idle from startup.
+            None => true,
+        }
+    }
 }
 
 /// Starts the gRPC server and the router for handling incoming requests.

rs/bitcoin/adapter/src/router.rs

@@ -49,8 +49,13 @@ pub fn start_main_event_loop(
 
     tokio::task::spawn(async move {
         let mut tick_interval = interval(Duration::from_millis(100));
+
         loop {
-            adapter_state.active().await;
+            if adapter_state.is_idle() {
+                connection_manager.make_idle();
+                blockchain_manager.make_idle();
+                adapter_state.active().await;
+            }
 
             // We do a select over tokio::sync::mpsc::Receiver::recv, tokio::sync::mpsc::UnboundedReceiver::recv,
             // tokio::time::Interval::tick which are all cancellation safe.
@@ -109,8 +114,6 @@ pub fn start_main_event_loop(
                     }
                 };
             }
-            connection_manager.make_idle();
-            blockchain_manager.make_idle();
         }
     });
 }