src/Core/Cache/RedisCacheDriver.php

   1 <?php
   2
   3 namespace Friendica\Core\Cache;
   4
   5 use Friendica\Core\Cache;
   6
   7 /**
   8  * Redis Cache Driver. This driver is based on Memcache driver
   9  *
  10  * @author Hypolite Petovan <mrpetovan@gmail.com>
  11  * @author Roland Haeder <roland@mxchange.org>
  12  */
  13 class RedisCacheDriver extends AbstractCacheDriver implements IMemoryCacheDriver
  14 {
  15         /**
  16          * @var \Redis
  17          */
  18         private $redis;
  19
  20         public function __construct($redis_host, $redis_port)
  21         {
  22                 if (!class_exists('Redis', false)) {
  23                         throw new \Exception('Redis class isn\'t available');
  24                 }
  25
  26                 $this->redis = new \Redis();
  27
  28                 if (!$this->redis->connect($redis_host, $redis_port)) {
  29                         throw new \Exception('Expected Redis server at ' . $redis_host . ':' . $redis_port . ' isn\'t available');
  30                 }
  31         }
  32
  33         public function get($key)
  34         {
  35                 $return = null;
  36                 $cachekey = $this->getCacheKey($key);
  37
  38                 $cached = $this->redis->get($cachekey);
  39                 if ($cached === false && !$this->redis->exists($cachekey)) {
  40                         return null;
  41                 }
  42
  43                 $value = json_decode($cached);
  44
  45                 // Only return a value if the serialized value is valid.
  46                 // We also check if the db entry is a serialized
  47                 // boolean 'false' value (which we want to return).
  48                 if ($cached === serialize(false) || $value !== false) {
  49                         $return = $value;
  50                 }
  51
  52                 return $return;
  53         }
  54
  55         public function set($key, $value, $ttl = Cache::FIVE_MINUTES)
  56         {
  57                 $cachekey = $this->getCacheKey($key);
  58
  59                 $cached = json_encode($value);
  60
  61                 if ($ttl > 0) {
  62                         return $this->redis->setex(
  63                                 $cachekey,
  64                                 time() + $ttl,
  65                                 $cached
  66                         );
  67                 } else {
  68                         return $this->redis->set(
  69                                 $cachekey,
  70                                 $cached
  71                         );
  72                 }
  73         }
  74
  75         public function delete($key)
  76         {
  77                 return $this->redis->delete($key);
  78         }
  79
  80         public function clear()
  81         {
  82                 return $this->redis->flushAll();
  83         }
  84
  85
  86         /**
  87          * (@inheritdoc)
  88          */
  89         public function add($key, $value, $ttl = Cache::FIVE_MINUTES)
  90         {
  91                 $cachekey = $this->getCacheKey($key);
  92                 $cached = json_encode($value);
  93
  94                 return $this->redis->setnx($cachekey, $value);
  95         }
  96
  97         /**
  98          * (@inheritdoc)
  99          */
 100         public function compareSet($key, $oldValue, $newValue, $ttl = Cache::FIVE_MINUTES)
 101         {
 102                 $cachekey = $this->getCacheKey($key);
 103
 104                 $newCached = json_encode($newValue);
 105
 106                 $this->redis->watch($cachekey);
 107                 // If the old value isn't what we expected, somebody else changed the key meanwhile
 108                 if ($this->get($key) === $oldValue) {
 109                         if ($ttl > 0) {
 110                                 $result = $this->redis->multi()
 111                                         ->setex($cachekey, $ttl, $newCached)
 112                                         ->exec();
 113                         } else {
 114                                 $result = $this->redis->multi()
 115                                         ->set($cachekey, $newValue)
 116                                         ->exec();
 117                         }
 118                         return $result !== false;
 119                 }
 120                 $this->redis->unwatch();
 121                 return false;
 122         }
 123         /**
 124          * (@inheritdoc)
 125          */
 126         public function compareDelete($key, $value)
 127         {
 128                 $cachekey = $this->getCacheKey($key);
 129
 130                 $this->redis->watch($cachekey);
 131                 // If the old value isn't what we expected, somebody else changed the key meanwhile
 132                 if ($this->get($key) === $value) {
 133                         $result = $this->redis->multi()
 134                                 ->del($cachekey)
 135                                 ->exec();
 136                         return $result !== false;
 137                 }
 138                 $this->redis->unwatch();
 139                 return false;
 140         }
 141 }