Demo Mode (#117)

* Adding Demo Mode to Fredy

lib/services/demoCleanup.js

@@ -0,0 +1,29 @@
+import { setInterval } from 'node:timers';
+import {removeJobsByUserName} from './storage/jobStorage.js';
+import {config} from '../utils.js';
+
+/**
+ * if we are running in demo environment, we have to cleanup the db files (specifically the jobs table)
+ */
+export function cleanupDemoAtMidnight() {
+    const now = new Date();
+    const millisUntilMidnightUTC = (24 - now.getUTCHours()) * 60 * 60 * 1000
+        - now.getUTCMinutes() * 60 * 1000
+        - now.getUTCSeconds() * 1000
+        - now.getUTCMilliseconds();
+
+    setTimeout(() => {
+        cleanup();
+
+        setInterval(() => {
+            cleanup();
+        }, 24 * 60 * 60 * 1000);
+
+    }, millisUntilMidnightUTC);
+}
+
+function cleanup(){
+    if(config.demoMode){
+        removeJobsByUserName('demo');
+    }
+}