src/Core/Cache/Type/DatabaseCache.php

   1 <?php
   2 /**
   3  * @copyright Copyright (C) 2010-2023, the Friendica project
   4  *
   5  * @license GNU AGPL version 3 or any later version
   6  *
   7  * This program is free software: you can redistribute it and/or modify
   8  * it under the terms of the GNU Affero General Public License as
   9  * published by the Free Software Foundation, either version 3 of the
  10  * License, or (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU Affero General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Affero General Public License
  18  * along with this program.  If not, see <https://www.gnu.org/licenses/>.
  19  *
  20  */
  21
  22 namespace Friendica\Core\Cache\Type;
  23
  24 use Friendica\Core\Cache\Capability\ICanCache;
  25 use Friendica\Core\Cache\Enum;
  26 use Friendica\Core\Cache\Exception\CachePersistenceException;
  27 use Friendica\Database\Database;
  28 use Friendica\Util\DateTimeFormat;
  29
  30 /**
  31  * Database Cache
  32  */
  33 class DatabaseCache extends AbstractCache implements ICanCache
  34 {
  35         public static $NAME = 'database';
  36
  37         /**
  38          * @var Database
  39          */
  40         private $dba;
  41
  42         public function __construct(string $hostname, Database $dba)
  43         {
  44                 parent::__construct($hostname);
  45
  46                 $this->dba = $dba;
  47         }
  48
  49         /**
  50          * (@inheritdoc)
  51          *
  52          * @throws CachePersistenceException
  53          */
  54         public function getAllKeys(?string $prefix = null): array
  55         {
  56                 try {
  57                         if (empty($prefix)) {
  58                                 $where = ['`expires` >= ?', DateTimeFormat::utcNow()];
  59                         } else {
  60                                 $where = ['`expires` >= ? AND `k` LIKE CONCAT(?, \'%\')', DateTimeFormat::utcNow(), $prefix];
  61                         }
  62
  63                         $stmt = $this->dba->select('cache', ['k'], $where);
  64
  65                         $keys = [];
  66                         while ($key = $this->dba->fetch($stmt)) {
  67                                 array_push($keys, $key['k']);
  68                         }
  69                 } catch (\Exception $exception) {
  70                         throw new CachePersistenceException(sprintf('Cannot fetch all keys with prefix %s', $prefix), $exception);
  71                 } finally {
  72                         $this->dba->close($stmt);
  73                 }
  74
  75                 return $keys;
  76         }
  77
  78         /**
  79          * (@inheritdoc)
  80          */
  81         public function get(string $key)
  82         {
  83                 try {
  84                         $cache = $this->dba->selectFirst('cache', ['v'], [
  85                                 '`k` = ? AND (`expires` >= ? OR `expires` = -1)', $key, DateTimeFormat::utcNow()
  86                         ]);
  87
  88                         if ($this->dba->isResult($cache)) {
  89                                 $cached = $cache['v'];
  90                                 $value  = @unserialize($cached);
  91
  92                                 // Only return a value if the serialized value is valid.
  93                                 // We also check if the db entry is a serialized
  94                                 // boolean 'false' value (which we want to return).
  95                                 if ($cached === serialize(false) || $value !== false) {
  96                                         return $value;
  97                                 }
  98                         }
  99                 } catch (\Exception $exception) {
 100                         throw new CachePersistenceException(sprintf('Cannot get cache entry with key %s', $key), $exception);
 101                 }
 102
 103                 return null;
 104         }
 105
 106         /**
 107          * (@inheritdoc)
 108          */
 109         public function set(string $key, $value, int $ttl = Enum\Duration::FIVE_MINUTES): bool
 110         {
 111                 try {
 112                         if ($ttl > 0) {
 113                                 $fields = [
 114                                         'v'       => serialize($value),
 115                                         'expires' => DateTimeFormat::utc('now + ' . $ttl . 'seconds'),
 116                                         'updated' => DateTimeFormat::utcNow()
 117                                 ];
 118                         } else {
 119                                 $fields = [
 120                                         'v'       => serialize($value),
 121                                         'expires' => -1,
 122                                         'updated' => DateTimeFormat::utcNow()
 123                                 ];
 124                         }
 125
 126                         return $this->dba->update('cache', $fields, ['k' => $key], true);
 127                 } catch (\Exception $exception) {
 128                         throw new CachePersistenceException(sprintf('Cannot set cache entry with key %s', $key), $exception);
 129                 }
 130         }
 131
 132         /**
 133          * (@inheritdoc)
 134          */
 135         public function delete(string $key): bool
 136         {
 137                 try {
 138                         return $this->dba->delete('cache', ['k' => $key]);
 139                 } catch (\Exception $exception) {
 140                         throw new CachePersistenceException(sprintf('Cannot delete cache entry with key %s', $key), $exception);
 141                 }
 142         }
 143
 144         /**
 145          * (@inheritdoc)
 146          */
 147         public function clear(bool $outdated = true): bool
 148         {
 149                 try {
 150                         if ($outdated) {
 151                                 return $this->dba->delete('cache', ['`expires` < ?', DateTimeFormat::utcNow()]);
 152                         } else {
 153                                 return $this->dba->delete('cache', ['`k` IS NOT NULL ']);
 154                         }
 155                 } catch (\Exception $exception) {
 156                         throw new CachePersistenceException('Cannot clear cache', $exception);
 157                 }
 158         }
 159 }