+ /**
+ * @brief Put data in the cache according to the key
+ *
+ * The input $value can have multiple formats.
+ *
+ * @param string $key The key to the cached data
+ * @param mixed $valie The value that is about to be stored
+ * @param integer $duration The cache lifespan
+ */
+ public static function set($key, $value, $duration = CACHE_MONTH) {
+
+ // Do we have an installed memcache? Use it instead.
+ $memcache = self::memcache();
+ if (is_object($memcache)) {
+ // We store with the hostname as key to avoid problems with other applications
+ $memcache->set(get_app()->get_hostname().":".$key, serialize($value), MEMCACHE_COMPRESSED, self::duration($duration));
+ return;
+ }
+
+ /// @todo store the cache data in the same way like the config data
+ q("REPLACE INTO `cache` (`k`,`v`,`expire_mode`,`updated`) VALUES ('%s','%s',%d,'%s')",
+ dbesc($key),
+ dbesc(serialize($value)),
+ intval($duration),
+ dbesc(datetime_convert()));
+ }
+
+ /**
+ * @brief Remove outdated data from the cache
+ *
+ * @param integer $maxlevel The maximum cache level that is to be cleared
+ */
+ public static function clear($max_level = CACHE_MONTH) {
+
+ // Clear long lasting cache entries only once a day
+ if (get_config("system", "cache_cleared_day") < time() - self::duration(CACHE_DAY)) {
+ if ($max_level == CACHE_MONTH) {
+ q("DELETE FROM `cache` WHERE `updated` < '%s' AND `expire_mode` = %d",
+ dbesc(datetime_convert('UTC','UTC',"now - 30 days")), intval(CACHE_MONTH));
+ }
+
+ if ($max_level <= CACHE_WEEK) {
+ q("DELETE FROM `cache` WHERE `updated` < '%s' AND `expire_mode` = %d",
+ dbesc(datetime_convert('UTC','UTC',"now - 7 days")), intval(CACHE_WEEK));
+ }
+
+ if ($max_level <= CACHE_DAY) {
+ q("DELETE FROM `cache` WHERE `updated` < '%s' AND `expire_mode` = %d",
+ dbesc(datetime_convert('UTC','UTC',"now - 1 days")), intval(CACHE_DAY));
+ }
+ set_config("system", "cache_cleared_day", time());
+ }
+
+ if (($max_level <= CACHE_HOUR) AND (get_config("system", "cache_cleared_hour")) < time() - self::duration(CACHE_HOUR)) {
+ q("DELETE FROM `cache` WHERE `updated` < '%s' AND `expire_mode` = %d",
+ dbesc(datetime_convert('UTC','UTC',"now - 1 hours")), intval(CACHE_HOUR));
+
+ set_config("system", "cache_cleared_hour", time());
+ }
+
+ if (($max_level <= CACHE_HALF_HOUR) AND (get_config("system", "cache_cleared_half_hour")) < time() - self::duration(CACHE_HALF_HOUR)) {
+ q("DELETE FROM `cache` WHERE `updated` < '%s' AND `expire_mode` = %d",
+ dbesc(datetime_convert('UTC','UTC',"now - 30 minutes")), intval(CACHE_HALF_HOUR));
+
+ set_config("system", "cache_cleared_half_hour", time());
+ }
+
+ if (($max_level <= CACHE_QUARTER_HOUR) AND (get_config("system", "cache_cleared_hour")) < time() - self::duration(CACHE_QUARTER_HOUR)) {
+ q("DELETE FROM `cache` WHERE `updated` < '%s' AND `expire_mode` = %d",
+ dbesc(datetime_convert('UTC','UTC',"now - 15 minutes")), intval(CACHE_QUARTER_HOUR));
+
+ set_config("system", "cache_cleared_quarter_hour", time());
+ }
+
+ if (($max_level <= CACHE_FIVE_MINUTES) AND (get_config("system", "cache_cleared_five_minute")) < time() - self::duration(CACHE_FIVE_MINUTES)) {
+ q("DELETE FROM `cache` WHERE `updated` < '%s' AND `expire_mode` = %d",
+ dbesc(datetime_convert('UTC','UTC',"now - 5 minutes")), intval(CACHE_FIVE_MINUTES));
+
+ set_config("system", "cache_cleared_five_minute", time());
+ }
+
+ if (($max_level <= CACHE_MINUTE) AND (get_config("system", "cache_cleared_minute")) < time() - self::duration(CACHE_MINUTE)) {
+ q("DELETE FROM `cache` WHERE `updated` < '%s' AND `expire_mode` = %d",
+ dbesc(datetime_convert('UTC','UTC',"now - 1 minutes")), intval(CACHE_MINUTE));