get_drones_for_pool() should return all drones + add index on drone(l…

…ast_heartbeat) (#781)

plane/schema/derived_schema.sql

@@ -952,6 +952,13 @@ CREATE INDEX idx_backend_static_token ON public.backend USING btree (static_toke
 CREATE UNIQUE INDEX idx_cluster_name ON public.node USING btree (cluster, name);
 
 
+--
+-- Name: idx_drone_last_heartbeat; Type: INDEX; Schema: public; Owner: postgres
+--
+
+CREATE INDEX idx_drone_last_heartbeat ON public.drone USING btree (last_heartbeat);
+
+
 --
 -- Name: idx_event_created_at; Type: INDEX; Schema: public; Owner: postgres
 --

plane/schema/migrations/20240709213841_add-index-on-drone-heartbeat.sql

@@ -0,0 +1 @@
+create index idx_drone_last_heartbeat on drone(last_heartbeat);

plane/src/database/drone.rs

@@ -95,14 +95,23 @@ impl<'a> DroneDatabase<'a> {
         Ok(result.pool.into())
     }
 
-    /// Returns a list of drones that are ready and have been seen in the last `seen_in_last` duration.
+    /// Returns a list of drones that have been seen in the last `seen_in_last` duration.
     /// Limits the result to the most recent 100 drones.
     pub async fn get_drones_for_pool(
         &self,
         cluster: &ClusterName,
         pool: &DronePoolName,
         seen_in_last: Duration,
     ) -> sqlx::Result<Vec<DroneWithMetadata>> {
+        // Converting to a PgInterval fails if the duration has nanosecond granularity.
+        // So let's round up to the nearest microsecond.
+        let seen_in_last = if seen_in_last.subsec_nanos() % 1000 == 0 {
+            seen_in_last
+        } else {
+            let nanos = (seen_in_last.subsec_micros() + 1) * 1000;
+            Duration::new(seen_in_last.as_secs(), nanos)
+        };
+
         let Ok(seen_in_last) = PgInterval::try_from(seen_in_last) else {
             return Err(sqlx::Error::Protocol("invalid interval".to_string()));
         };
@@ -124,8 +133,7 @@ impl<'a> DroneDatabase<'a> {
             from node
             left join drone on node.id = drone.id
             where
-                drone.ready = true
-                and controller is not null
+                controller is not null
                 and cluster = $1
                 and now() - drone.last_heartbeat < $2
                 and pool = $3