first commit

backend/includes/Redis.php

@@ -0,0 +1,55 @@
+<?php
+/**
+ * Redis Singleton — phpredis Extension
+ */
+
+require_once __DIR__ . '/../config.php';
+
+class RedisClient
+{
+    private static ?\Redis $instance = null;
+
+    private function __construct()
+    {
+        try {
+            self::$instance = new \Redis();
+            self::$instance->connect(REDIS_HOST, REDIS_PORT, 2.0);
+
+            if (REDIS_PASSWORD !== null) {
+                self::$instance->auth(REDIS_PASSWORD);
+            }
+
+            if (REDIS_DB > 0) {
+                self::$instance->select(REDIS_DB);
+            }
+
+            self::$instance->setOption(\Redis::OPT_SERIALIZER, \Redis::SERIALIZER_JSON);
+        } catch (\RedisException $e) {
+            $errorMsg = $e->getMessage();
+            error_log('Redis connection failed: ' . $errorMsg);
+            http_response_code(500);
+            echo json_encode(['success' => false, 'message' => 'cache_error', 'error' => $errorMsg]);
+            exit;
+        } catch (\Exception $e) {
+            $errorMsg = $e->getMessage();
+            error_log('Unexpected error in Redis: ' . $errorMsg);
+            http_response_code(500);
+            echo json_encode(['success' => false, 'message' => 'cache_error', 'error' => $errorMsg]);
+            exit;
+        }
+    }
+
+    public static function getInstance(): \Redis
+    {
+        if (self::$instance === null) {
+            new self();
+        }
+        return self::$instance;
+    }
+
+    private function __clone() {}
+    public function __wakeup()
+    {
+        throw new \Exception("Cannot unserialize singleton");
+    }
+}