Delete old pings also on startup

lib/database.js

@@ -267,12 +267,18 @@ class Database {
     statement.finalize()
   }
 
-  initOldPingsDeleter () {
-    // Delete old records every hour
-    setInterval(() => this.deleteOldPingRecords(), 3600000)
+  initOldPingsDelete (callback) {
+    // Delete old ping records on startup
+    logger.info('Deleting old ping records..')
+    this.deleteOldPingRecords(() => {
+      // Delete old ping records every hour
+      setInterval(() => this.deleteOldPingRecords(), 3600000)
+
+      callback()
+    })
   }
 
-  deleteOldPingRecords () {
+  deleteOldPingRecords (callback) {
     // The oldest timestamp that will be kept
     const oldestTimestamp = TimeTracker.getEpochMillis() - config.graphDuration
 
@@ -285,6 +291,10 @@ class Database {
       } else {
         const deleteTook = TimeTracker.getEpochMillis() - deleteStart
         logger.info(`Old ping records deleted in ${deleteTook}ms`)
+
+        if (callback !== undefined) {
+          callback()
+        }
       }
     })
     statement.finalize()