X-Git-Url: https://git.mxchange.org/?a=blobdiff_plain;f=include%2Fcache.php;h=d3b24c19e771e8085ec19e80cf19399fae769a48;hb=0cd9db9cb7f4c96f597e37590a536eaae123238d;hp=d0b0dfafda9c4fc011102bf6a2fa0cd3cbc00d1b;hpb=4b6afbf6814acde5151edc74f0b6cf1fd7685432;p=friendica.git

diff --git a/include/cache.php b/include/cache.php
index d0b0dfafda..d3b24c19e7 100644
--- a/include/cache.php
+++ b/include/cache.php
@@ -1,72 +1,210 @@
 <?php
+/**
+ * @file include/cache.php
+ *
+ * @brief Class for storing data for a short time
+ */
+
+use Friendica\Core\Config;
+use Friendica\Core\PConfig;
+
+class Cache {
+	/**
+	 * @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;
+	}
+
 	/**
-	 *  cache api
+	 * @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;
+	}
 
-	class Cache {
-		public static function get($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) {
 
-			$r = q("SELECT `v` FROM `cache` WHERE `k`='%s' limit 1",
-				dbesc($key)
-			);
+		$memcache = self::memcache();
+		if (is_object($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);
 
-			if (count($r))
-				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, $duration = CACHE_MONTH) {
+		// Frequently clear cache
+		self::clear($duration);
+
+		$r = q("SELECT `v` FROM `cache` WHERE `k`='%s' LIMIT 1",
+			dbesc($key)
+		);
 
-			q("REPLACE INTO `cache` (`k`,`v`,`expire_mode`,`updated`) VALUES ('%s','%s',%d,'%s')",
-					dbesc($key),
-					dbesc($value),
-					intval($duration),
-					dbesc(datetime_convert()));
+		if (dbm::is_result($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) {
+
+		// 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;
+		}
 
-/*
- *			$r = q("SELECT * FROM `cache` WHERE `k`='%s' limit 1",
- *				dbesc($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($value),
- *					dbesc(datetime_convert()));
- *			}
- *		}
- */
+		/// @todo store the cache data in the same way like the config data
+		q("REPLACE INTO `cache` (`k`,`v`,`expire_mode`,`updated`) VALUES ('%s','%s',%d,'%s')",
+				dbesc($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());
+		}
 
-		public static function clear(){
+		if (($max_level <= CACHE_HOUR) && (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 - 30 days")), intval(CACHE_MONTH));
+				dbesc(datetime_convert('UTC','UTC',"now - 1 hours")), intval(CACHE_HOUR));
+
+			set_config("system", "cache_cleared_hour", time());
+		}
 
+		if (($max_level <= CACHE_HALF_HOUR) && (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 - 7 days")), intval(CACHE_WEEK));
+				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) && (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 - 1 days")), intval(CACHE_DAY));
+				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) && (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 - 1 hours")), intval(CACHE_HOUR));
+				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) && (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());
+		}
+	}
+}