'datetime', 'finished_at' => 'datetime', ]; protected static function booted() { MaintenanceHistory::observe(MaintenanceHistoryObserver::class); } public function maintenance() { return $this->BelongsTo(Maintenance::class); } public function historyHosts() { return $this->hasMany(MaintenanceHostHistory::class); } public function guestor() { return $this->BelongsTo(User::class, 'guestor_id'); } }