src/Core/Cache/Type/DatabaseCache.php

   1 <?php
   2 /**
   3  * @copyright Copyright (C) 2010-2022, 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         /**
  36          * @var Database
  37          */
  38         private $dba;
  39
  40         public function __construct(string $hostname, Database $dba)
  41         {
  42                 parent::__construct($hostname);
  43
  44                 $this->dba = $dba;
  45         }
  46
  47         /**
  48          * (@inheritdoc)
  49          *
  50          * @throws CachePersistenceException
  51          */
  52         public function getAllKeys(?string $prefix = null): array
  53         {
  54                 try {
  55                         if (empty($prefix)) {
  56                                 $where = ['`expires` >= ?', DateTimeFormat::utcNow()];
  57                         } else {
  58                                 $where = ['`expires` >= ? AND `k` LIKE CONCAT(?, \'%\')', DateTimeFormat::utcNow(), $prefix];
  59                         }
  60
  61                         $stmt = $this->dba->select('cache', ['k'], $where);
  62
  63                         $keys = [];
  64                         while ($key = $this->dba->fetch($stmt)) {
  65                                 array_push($keys, $key['k']);
  66                         }
  67                 } catch (\Exception $exception) {
  68                         throw new CachePersistenceException(sprintf('Cannot fetch all keys with prefix %s', $prefix), $exception);
  69                 } finally {
  70                         $this->dba->close($stmt);
  71                 }
  72
  73                 return $keys;
  74         }
  75
  76         /**
  77          * (@inheritdoc)
  78          */
  79         public function get(string $key)
  80         {
  81                 try {
  82                         $cache = $this->dba->selectFirst('cache', ['v'], [
  83                                 '`k` = ? AND (`expires` >= ? OR `expires` = -1)', $key, DateTimeFormat::utcNow()
  84                         ]);
  85
  86                         if ($this->dba->isResult($cache)) {
  87                                 $cached = $cache['v'];
  88                                 $value  = @unserialize($cached);
  89
  90                                 // Only return a value if the serialized value is valid.
  91                                 // We also check if the db entry is a serialized
  92                                 // boolean 'false' value (which we want to return).
  93                                 if ($cached === serialize(false) || $value !== false) {
  94                                         return $value;
  95                                 }
  96                         }
  97                 } catch (\Exception $exception) {
  98                         throw new CachePersistenceException(sprintf('Cannot get cache entry with key %s', $key), $exception);
  99                 }
 100
 101                 return null;
 102         }
 103
 104         /**
 105          * (@inheritdoc)
 106          */
 107         public function set(string $key, $value, int $ttl = Enum\Duration::FIVE_MINUTES): bool
 108         {
 109                 try {
 110                         if ($ttl > 0) {
 111                                 $fields = [
 112                                         'v'       => serialize($value),
 113                                         'expires' => DateTimeFormat::utc('now + ' . $ttl . 'seconds'),
 114                                         'updated' => DateTimeFormat::utcNow()
 115                                 ];
 116                         } else {
 117                                 $fields = [
 118                                         'v'       => serialize($value),
 119                                         'expires' => -1,
 120                                         'updated' => DateTimeFormat::utcNow()
 121                                 ];
 122                         }
 123
 124                         return $this->dba->update('cache', $fields, ['k' => $key], true);
 125                 } catch (\Exception $exception) {
 126                         throw new CachePersistenceException(sprintf('Cannot set cache entry with key %s', $key), $exception);
 127                 }
 128         }
 129
 130         /**
 131          * (@inheritdoc)
 132          */
 133         public function delete(string $key): bool
 134         {
 135                 try {
 136                         return $this->dba->delete('cache', ['k' => $key]);
 137                 } catch (\Exception $exception) {
 138                         throw new CachePersistenceException(sprintf('Cannot delete cache entry with key %s', $key), $exception);
 139                 }
 140         }
 141
 142         /**
 143          * (@inheritdoc)
 144          */
 145         public function clear(bool $outdated = true): bool
 146         {
 147                 try {
 148                         if ($outdated) {
 149                                 return $this->dba->delete('cache', ['`expires` < ?', DateTimeFormat::utcNow()]);
 150                         } else {
 151                                 return $this->dba->delete('cache', ['`k` IS NOT NULL ']);
 152                         }
 153                 } catch (\Exception $exception) {
 154                         throw new CachePersistenceException('Cannot clear cache', $exception);
 155                 }
 156         }
 157
 158         /**
 159          * {@inheritDoc}
 160          */
 161         public function getName(): string
 162         {
 163                 return Enum\Type::DATABASE;
 164         }
 165 }