confirms/app/Config/Session.php

<?php

namespace Config;

use CodeIgniter\Config\BaseConfig;
use CodeIgniter\Session\Handlers\BaseHandler;
use CodeIgniter\Session\Handlers\DatabaseHandler;
use CodeIgniter\Session\Handlers\RedisHandler;

class Session extends BaseConfig
{
    /**
     * --------------------------------------------------------------------------
     * Session Driver
     * --------------------------------------------------------------------------
     *
     * The session storage driver to use:
     * - `CodeIgniter\Session\Handlers\DatabaseHandler`
     * - `CodeIgniter\Session\Handlers\RedisHandler`
     *
     * @var class-string<BaseHandler>
     */
    public string $driver = RedisHandler::class;

    /**
     * --------------------------------------------------------------------------
     * Session Cookie Name
     * --------------------------------------------------------------------------
     *
     * The session cookie name, must contain only [0-9a-z_-] characters
     */
    public string $cookieName = 'ci_session';

    /**
     * --------------------------------------------------------------------------
     * Session Expiration
     * --------------------------------------------------------------------------
     *
     * The number of SECONDS you want the session to last.
     * Setting to 0 (zero) means expire when the browser is closed.
     */
    public int $expiration = 7200;

    /**
     * --------------------------------------------------------------------------
     * Session Save Path
     * --------------------------------------------------------------------------
     *
     * The location to save sessions to and is driver dependent.
     *
     * For the 'database' driver, it's a table name.
     * For Redis: tcp://host:port?database=n&password=xxx
     *
     * IMPORTANT: You are REQUIRED to set a valid save path!
     */
    public string $savePath;

    public function __construct()
    {
        parent::__construct();

        // 환경변수로 강제로 Database 모드 설정 가능 (Redis 장애 시 수동 전환)
        $forceDatabase = env('SESSION_FORCE_DATABASE', false);

        // Redis 설정: Redis 연결 실패 시 Database로 폴백
        if ($this->driver === RedisHandler::class && !$forceDatabase) {
            helper('redis');
            
            try {
                // Redis 연결 테스트
                $testRedis = get_redis_connection('session');
                
                if (!$testRedis) {
                    throw new \Exception('Redis connection failed');
                }
                
                // Redis 정상 - Redis 설정 사용
                $config = get_redis_config('session');
                
                $this->savePath = sprintf(
                    'tcp://%s:%s?database=%s',
                    $config['host'],
                    $config['port'],
                    $config['database']
                );

                if (!empty($config['password'])) {
                    $this->savePath .= '&password=' . $config['password'];
                }
                
            } catch (\Exception $e) {
                // Redis 실패 - DatabaseHandler로 폴백
                log_message('warning', 'Session: Redis unavailable (' . $e->getMessage() . '), falling back to DatabaseHandler');
                $this->driver = DatabaseHandler::class;
                $this->savePath = 'ci_sessions';  // 테이블 이름
            }
        } else {
            // Database 강제 모드 또는 기본 Database 설정
            if ($forceDatabase && $this->driver === RedisHandler::class) {
                log_message('info', 'Session: Forced to use DatabaseHandler (SESSION_FORCE_DATABASE=true)');
                $this->driver = DatabaseHandler::class;
            }
            $this->savePath = 'ci_sessions';
        }
    }

    /**
     * --------------------------------------------------------------------------
     * Session Match IP
     * --------------------------------------------------------------------------
     *
     * Whether to match the user's IP address when reading the session data.
     *
     * WARNING: If you're using the database driver, don't forget to update
     *          your session table's PRIMARY KEY when changing this setting.
     */
    public bool $matchIP = false;

    /**
     * --------------------------------------------------------------------------
     * Session Time to Update
     * --------------------------------------------------------------------------
     *
     * How many seconds between CI regenerating the session ID.
     */
    public int $timeToUpdate = 300;

    /**
     * --------------------------------------------------------------------------
     * Session Regenerate Destroy
     * --------------------------------------------------------------------------
     *
     * Whether to destroy session data associated with the old session ID
     * when auto-regenerating the session ID. When set to FALSE, the data
     * will be later deleted by the garbage collector.
     */
    public bool $regenerateDestroy = false;

    /**
     * --------------------------------------------------------------------------
     * Session Database Group
     * --------------------------------------------------------------------------
     *
     * DB Group for the database session.
     */
    public ?string $DBGroup = null;

    /**
     * --------------------------------------------------------------------------
     * Lock Retry Interval (microseconds)
     * --------------------------------------------------------------------------
     *
     * This is used for RedisHandler.
     *
     * Time (microseconds) to wait if lock cannot be acquired.
     * The default is 100,000 microseconds (= 0.1 seconds).
     */
    public int $lockRetryInterval = 100_000;

    /**
     * --------------------------------------------------------------------------
     * Lock Max Retries
     * --------------------------------------------------------------------------
     *
     * This is used for RedisHandler.
     *
     * Maximum number of lock acquisition attempts.
     * The default is 300 times. That is lock timeout is about 30 (0.1 * 300)
     * seconds.
     */
    public int $lockMaxRetries = 300;
}