1: <?php
  2: /**
  3:  * CakePHP(tm) : Rapid Development Framework (https://cakephp.org)
  4:  * Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
  5:  *
  6:  * Licensed under The MIT License
  7:  * For full copyright and license information, please see the LICENSE.txt
  8:  * Redistributions of files must retain the above copyright notice.
  9:  *
 10:  * @copyright     Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
 11:  * @link          https://cakephp.org CakePHP(tm) Project
 12:  * @since         3.7.0
 13:  * @license       https://opensource.org/licenses/mit-license.php MIT License
 14:  */
 15: namespace Cake\Cache\Engine;
 16: 
 17: use Cake\Cache\CacheEngine;
 18: 
 19: /**
 20:  * Array storage engine for cache.
 21:  *
 22:  * Not actually a persistent cache engine. All data is only
 23:  * stored in memory for the duration of a single process. While not
 24:  * useful in production settings this engine can be useful in tests
 25:  * or console tools where you don't want the overhead of interacting
 26:  * with a cache servers, but want the work saving properties a cache
 27:  * provides.
 28:  */
 29: class ArrayEngine extends CacheEngine
 30: {
 31:     /**
 32:      * Cached data.
 33:      *
 34:      * Structured as [key => [exp => expiration, val => value]]
 35:      *
 36:      * @var array
 37:      */
 38:     protected $data = [];
 39: 
 40:     /**
 41:      * Write data for key into cache
 42:      *
 43:      * @param string $key Identifier for the data
 44:      * @param mixed $value Data to be cached
 45:      * @return bool True if the data was successfully cached, false on failure
 46:      */
 47:     public function write($key, $value)
 48:     {
 49:         $key = $this->_key($key);
 50:         $expires = time() + $this->_config['duration'];
 51:         $this->data[$key] = ['exp' => $expires, 'val' => $value];
 52: 
 53:         return true;
 54:     }
 55: 
 56:     /**
 57:      * Read a key from the cache
 58:      *
 59:      * @param string $key Identifier for the data
 60:      * @return mixed The cached data, or false if the data doesn't exist,
 61:      *   has expired, or if there was an error fetching it
 62:      */
 63:     public function read($key)
 64:     {
 65:         $key = $this->_key($key);
 66:         if (!isset($this->data[$key])) {
 67:             return false;
 68:         }
 69:         $data = $this->data[$key];
 70: 
 71:         // Check expiration
 72:         $now = time();
 73:         if ($data['exp'] <= $now) {
 74:             unset($this->data[$key]);
 75: 
 76:             return false;
 77:         }
 78: 
 79:         return $data['val'];
 80:     }
 81: 
 82:     /**
 83:      * Increments the value of an integer cached key
 84:      *
 85:      * @param string $key Identifier for the data
 86:      * @param int $offset How much to increment
 87:      * @return int|false New incremented value, false otherwise
 88:      */
 89:     public function increment($key, $offset = 1)
 90:     {
 91:         if (!$this->read($key)) {
 92:             $this->write($key, 0);
 93:         }
 94:         $key = $this->_key($key);
 95:         $this->data[$key]['val'] += $offset;
 96: 
 97:         return $this->data[$key]['val'];
 98:     }
 99: 
100:     /**
101:      * Decrements the value of an integer cached key
102:      *
103:      * @param string $key Identifier for the data
104:      * @param int $offset How much to subtract
105:      * @return int|false New decremented value, false otherwise
106:      */
107:     public function decrement($key, $offset = 1)
108:     {
109:         if (!$this->read($key)) {
110:             $this->write($key, 0);
111:         }
112:         $key = $this->_key($key);
113:         $this->data[$key]['val'] -= $offset;
114: 
115:         return $this->data[$key]['val'];
116:     }
117: 
118:     /**
119:      * Delete a key from the cache
120:      *
121:      * @param string $key Identifier for the data
122:      * @return bool True if the value was successfully deleted, false if it didn't exist or couldn't be removed
123:      */
124:     public function delete($key)
125:     {
126:         $key = $this->_key($key);
127:         unset($this->data[$key]);
128: 
129:         return true;
130:     }
131: 
132:     /**
133:      * Delete all keys from the cache. This will clear every cache config using APC.
134:      *
135:      * @param bool $check Unused argument required by interface.
136:      * @return bool True Returns true.
137:      */
138:     public function clear($check)
139:     {
140:         $this->data = [];
141: 
142:         return true;
143:     }
144: 
145:     /**
146:      * Returns the `group value` for each of the configured groups
147:      * If the group initial value was not found, then it initializes
148:      * the group accordingly.
149:      *
150:      * @return array
151:      */
152:     public function groups()
153:     {
154:         $result = [];
155:         foreach ($this->_config['groups'] as $group) {
156:             $key = $this->_config['prefix'] . $group;
157:             if (!isset($this->data[$key])) {
158:                 $this->data[$key] = ['exp' => PHP_INT_MAX, 'val' => 1];
159:             }
160:             $value = $this->data[$key]['val'];
161:             $result[] = $group . $value;
162:         }
163: 
164:         return $result;
165:     }
166: 
167:     /**
168:      * Increments the group value to simulate deletion of all keys under a group
169:      * old values will remain in storage until they expire.
170:      *
171:      * @param string $group The group to clear.
172:      * @return bool success
173:      */
174:     public function clearGroup($group)
175:     {
176:         $key = $this->_config['prefix'] . $group;
177:         if (isset($this->data[$key])) {
178:             $this->data[$key]['val'] += 1;
179:         }
180: 
181:         return true;
182:     }
183: }
184: