<?php
+/**
+ * @file include/cache.php
+ *
+ * @brief Class for storing data for a short time
+ */
+
+use Friendica\Core\Config;
+use Friendica\Core\PConfig;
+
+class Cache {
/**
- * cache api
+ * @brief Check for memcache and open a connection if configured
+ *
+ * @return object|boolean The memcache object - or "false" if not successful
*/
+ public static function memcache() {
+ if (!function_exists('memcache_connect')) {
+ return false;
+ }
+
+ if (!Config::get('system', 'memcache')) {
+ return false;
+ }
+
+ $memcache_host = Config::get('system', 'memcache_host', '127.0.0.1');
+ $memcache_port = Config::get('system', 'memcache_port', 11211);
+
+ $memcache = new Memcache;
+
+ if (!$memcache->connect($memcache_host, $memcache_port)) {
+ return false;
+ }
+
+ return $memcache;
+ }
- class Cache {
- public static function get($key) {
- /*if (function_exists("apc_fetch") AND function_exists("apc_exists"))
- if (apc_exists($key))
- return(apc_fetch($key));*/
+ /**
+ * @brief Return the duration for a given cache level
+ *
+ * @param integer $level Cache level
+ *
+ * @return integer The cache duration in seconds
+ */
+ private function duration($level) {
+ switch($level) {
+ case CACHE_MONTH;
+ $seconds = 2592000;
+ break;
+ case CACHE_WEEK;
+ $seconds = 604800;
+ break;
+ case CACHE_DAY;
+ $seconds = 86400;
+ break;
+ case CACHE_HOUR;
+ $seconds = 3600;
+ break;
+ case CACHE_HALF_HOUR;
+ $seconds = 1800;
+ break;
+ case CACHE_QUARTER_HOUR;
+ $seconds = 900;
+ break;
+ case CACHE_FIVE_MINUTES;
+ $seconds = 300;
+ break;
+ case CACHE_MINUTE;
+ $seconds = 60;
+ break;
+ }
+ return $seconds;
+ }
- $r = q("SELECT `v` FROM `cache` WHERE `k`='%s' limit 1",
- dbesc($key)
- );
+ /**
+ * @brief Fetch cached data according to the key
+ *
+ * @param string $key The key to the cached data
+ *
+ * @return mixed Cached $value or "null" if not found
+ */
+ public static function get($key) {
- if (count($r)) {
- /*if (function_exists("apc_store"))
- apc_store($key, $r[0]['v'], 600);*/
+ $memcache = self::memcache();
+ if (is_object($memcache)) {
+ // We fetch with the hostname as key to avoid problems with other applications
+ $cached = $memcache->get(get_app()->get_hostname().":".$key);
+ $value = @unserialize($cached);
- return $r[0]['v'];
+ // Only return a value if the serialized value is valid.
+ // We also check if the db entry is a serialized
+ // boolean 'false' value (which we want to return).
+ if ($cached === serialize(false) || $value !== false) {
+ return $value;
}
+
return null;
}
- public static function set($key,$value) {
+ // Frequently clear cache
+ self::clear($duration);
- q("REPLACE INTO `cache` (`k`,`v`,`updated`) VALUES ('%s','%s','%s')",
- dbesc($key),
- dbesc($value),
- dbesc(datetime_convert()));
+ $r = q("SELECT `v` FROM `cache` WHERE `k`='%s' LIMIT 1",
+ dbesc($key)
+ );
- /*if (function_exists("apc_store"))
- apc_store($key, $value, 600);*/
+ if (dbm::is_result($r)) {
+ $cached = $r[0]['v'];
+ $value = @unserialize($cached);
+ // Only return a value if the serialized value is valid.
+ // We also check if the db entry is a serialized
+ // boolean 'false' value (which we want to return).
+ if ($cached === serialize(false) || $value !== false) {
+ return $value;
+ }
}
+ return null;
+ }
-/*
- *
- * Leaving this legacy code temporaily to see how REPLACE fares
- * as opposed to non-atomic checks when faced with fast moving key duplication.
- * As a MySQL extension it isn't portable, but we're not yet very portable.
- */
+ /**
+ * @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) {
-/*
- * $r = q("SELECT * FROM `cache` WHERE `k`='%s' limit 1",
- * dbesc($key)
- * );
- * if(count($r)) {
- * q("UPDATE `cache` SET `v` = '%s', `updated = '%s' WHERE `k` = '%s'",
- * dbesc($value),
- * dbesc(datetime_convert()),
- * dbesc($key));
- * }
- * else {
- * q("INSERT INTO `cache` (`k`,`v`,`updated`) VALUES ('%s','%s','%s')",
- * dbesc($key),
- * dbesc($value),
- * dbesc(datetime_convert()));
- * }
- * }
- */
+ // 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()));
+ }
- public static function clear(){
- q("DELETE FROM `cache` WHERE `updated` < '%s'",
- dbesc(datetime_convert('UTC','UTC',"now - 30 days")));
+ /**
+ * @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_quarter_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));
+
+ set_config("system", "cache_cleared_minute", time());
+ }
+ }
+}
projects / friendica.git / blobdiff