Revert "move rpc_server to drop() semantics instead of having its own thread"

This reverts commit 40aa0654fa.

src/fullnode.rs

@@ -24,7 +24,6 @@ use window;
 pub struct Fullnode {
     exit: Arc<AtomicBool>,
     thread_hdls: Vec<JoinHandle<()>>,
-    _rpc_service: JsonRpcService,
 }
 
 #[derive(Serialize, Deserialize, Clone, Debug, PartialEq)]
@@ -191,8 +190,14 @@ impl Fullnode {
         let mut drone_addr = node.info.contact_info.tpu;
         drone_addr.set_port(DRONE_PORT);
         let rpc_addr = SocketAddr::new(IpAddr::V4(Ipv4Addr::from(0)), RPC_PORT);
-        let _rpc_service =
-            JsonRpcService::new(&bank, node.info.contact_info.tpu, drone_addr, rpc_addr);
+        let rpc_service = JsonRpcService::new(
+            &bank,
+            node.info.contact_info.tpu,
+            drone_addr,
+            rpc_addr,
+            exit.clone(),
+        );
+        thread_hdls.extend(rpc_service.thread_hdls());
 
         let blob_recycler = BlobRecycler::default();
         let window =
@@ -261,11 +266,7 @@ impl Fullnode {
             }
         }
 
-        Fullnode {
-            exit,
-            thread_hdls,
-            _rpc_service,
-        }
+        Fullnode { exit, thread_hdls }
     }
 
     //used for notifying many nodes in parallel to exit