judge: add warning for no host configured

packages/hydrojudge/src/daemon.ts

@@ -14,7 +14,7 @@
 import './utils';
 
 import PQueue from 'p-queue';
-import { fs } from '@hydrooj/utils';
+import { fs, Time } from '@hydrooj/utils';
 import { getConfig } from './config';
 import HydroHost from './hosts/hydro';
 import Vj4Host from './hosts/vj4';
@@ -53,6 +53,10 @@ async function daemon() {
     const queue = new PQueue({ concurrency: Infinity });
     await fs.ensureDir(getConfig('tmp_dir'));
     queue.on('error', (e) => log.error(e));
+    if (!Object.keys(_hosts).length) {
+        log.warn('No host configured');
+        setInterval(() => log.warn('No host configured'), Time.hour);
+    }
     for (const i in _hosts) {
         _hosts[i].host ||= i;
         hosts[i] = _hosts[i].type === 'vj4' ? new Vj4Host(_hosts[i]) : new HydroHost(_hosts[i]);