Prevent deleting VSTP services when completing full download.

dbAccess/cif.go

@@ -108,6 +108,19 @@ func DeleteCifEntries(deletions []database.DeleteQuery) error {
 	return nil
 }
 
+// Clears all non-vstp services from the database.  Used when a CIF full download is required.
+func PurgeNonVstp() (int64, error) {
+	coll := MongoClient.Database(DatabaseName).Collection(TimetableCollection)
+	filter := bson.M{"serviceDetail.vstp": false}
+
+	result, err := coll.DeleteMany(context.Background(), filter)
+	if err != nil {
+		return result.DeletedCount, err
+	}
+
+	return result.DeletedCount, nil
+}
+
 // Handles 'Create' tasks for CIF Schedule updates, accepts Service structs and batches their creation.
 func CreateCifEntries(schedules []database.Service) error {
 	// Skip if deletions is empty