fix: bug

app/core/redis.php

@@ -1,14 +1,31 @@
 <?php
 
-function redisClient(): Redis
+function redisClient(): ?Redis
 {
     static $redis = null;
+    static $initialized = false;
+
+    if ($initialized) {
+        return $redis;
+    }
+
+    $initialized = true;
+
+    if (!class_exists('Redis')) {
+        return null;
+    }
+
     if ($redis === null) {
         $config = require __DIR__ . '/../config/config.php';
         $redis  = new Redis();
-        if (!@$redis->connect($config['redis']['host'], $config['redis']['port'])) {
-            throw new RuntimeException('Redis connection failed.');
+        try {
+            if (!@$redis->connect($config['redis']['host'], $config['redis']['port'])) {
+                $redis = null;
+            }
+        } catch (Throwable $e) {
+            $redis = null;
         }
     }
+
     return $redis;
 }