user['id']); $servers = []; $userService = new UserService(); if ($userService->isAvailable($user)) { $serverService = new ServerService(); $servers = $serverService->getAvailableServers($user); } $eTag = sha1(json_encode(array_column($servers, 'updated_at'))); if (strpos($request->header('If-None-Match'), $eTag) !== false ) { abort(304); } return response([ 'data' => $servers ])->header('ETag', "\"{$eTag}\""); } }