1: <?php
  2: 
  3: /**
  4:  * This file is part of the Nette Framework (https://nette.org)
  5:  * Copyright (c) 2004 David Grudl (https://davidgrudl.com)
  6:  */
  7: 
  8: namespace Nette\Caching\Storages;
  9: 
 10: use Nette;
 11: use Nette\Caching\Cache;
 12: 
 13: 
 14: /**
 15:  * SQLite based journal.
 16:  */
 17: class SQLiteJournal implements IJournal
 18: {
 19:     use Nette\SmartObject;
 20: 
 21:     /** @string */
 22:     private $path;
 23: 
 24:     /** @var \PDO */
 25:     private $pdo;
 26: 
 27: 
 28:     /**
 29:      * @param  string  $path
 30:      */
 31:     public function __construct($path)
 32:     {
 33:         if (!extension_loaded('pdo_sqlite')) {
 34:             throw new Nette\NotSupportedException('SQLiteJournal requires PHP extension pdo_sqlite which is not loaded.');
 35:         }
 36:         $this->path = $path;
 37:     }
 38: 
 39: 
 40:     private function open()
 41:     {
 42:         if ($this->path !== ':memory:' && !is_file($this->path)) {
 43:             touch($this->path); // ensures ordinary file permissions
 44:         }
 45: 
 46:         $this->pdo = new \PDO('sqlite:' . $this->path);
 47:         $this->pdo->setAttribute(\PDO::ATTR_ERRMODE, \PDO::ERRMODE_EXCEPTION);
 48:         $this->pdo->exec('
 49:             PRAGMA foreign_keys = OFF;
 50:             PRAGMA journal_mode = WAL;
 51:             CREATE TABLE IF NOT EXISTS tags (
 52:                 key BLOB NOT NULL,
 53:                 tag BLOB NOT NULL
 54:             );
 55:             CREATE TABLE IF NOT EXISTS priorities (
 56:                 key BLOB NOT NULL,
 57:                 priority INT NOT NULL
 58:             );
 59:             CREATE INDEX IF NOT EXISTS idx_tags_tag ON tags(tag);
 60:             CREATE UNIQUE INDEX IF NOT EXISTS idx_tags_key_tag ON tags(key, tag);
 61:             CREATE UNIQUE INDEX IF NOT EXISTS idx_priorities_key ON priorities(key);
 62:             CREATE INDEX IF NOT EXISTS idx_priorities_priority ON priorities(priority);
 63:         ');
 64:     }
 65: 
 66: 
 67:     public function write($key, array $dependencies)
 68:     {
 69:         if (!$this->pdo) {
 70:             $this->open();
 71:         }
 72:         $this->pdo->exec('BEGIN');
 73: 
 74:         if (!empty($dependencies[Cache::TAGS])) {
 75:             $this->pdo->prepare('DELETE FROM tags WHERE key = ?')->execute([$key]);
 76: 
 77:             foreach ((array) $dependencies[Cache::TAGS] as $tag) {
 78:                 $arr[] = $key;
 79:                 $arr[] = $tag;
 80:             }
 81:             $this->pdo->prepare('INSERT INTO tags (key, tag) SELECT ?, ?' . str_repeat('UNION SELECT ?, ?', count($arr) / 2 - 1))
 82:                 ->execute($arr);
 83:         }
 84: 
 85:         if (!empty($dependencies[Cache::PRIORITY])) {
 86:             $this->pdo->prepare('REPLACE INTO priorities (key, priority) VALUES (?, ?)')
 87:                 ->execute([$key, (int) $dependencies[Cache::PRIORITY]]);
 88:         }
 89: 
 90:         $this->pdo->exec('COMMIT');
 91:     }
 92: 
 93: 
 94:     public function clean(array $conditions)
 95:     {
 96:         if (!$this->pdo) {
 97:             $this->open();
 98:         }
 99:         if (!empty($conditions[Cache::ALL])) {
100:             $this->pdo->exec('
101:                 BEGIN;
102:                 DELETE FROM tags;
103:                 DELETE FROM priorities;
104:                 COMMIT;
105:             ');
106: 
107:             return null;
108:         }
109: 
110:         $unions = $args = [];
111:         if (!empty($conditions[Cache::TAGS])) {
112:             $tags = (array) $conditions[Cache::TAGS];
113:             $unions[] = 'SELECT DISTINCT key FROM tags WHERE tag IN (?' . str_repeat(', ?', count($tags) - 1) . ')';
114:             $args = $tags;
115:         }
116: 
117:         if (!empty($conditions[Cache::PRIORITY])) {
118:             $unions[] = 'SELECT DISTINCT key FROM priorities WHERE priority <= ?';
119:             $args[] = (int) $conditions[Cache::PRIORITY];
120:         }
121: 
122:         if (empty($unions)) {
123:             return [];
124:         }
125: 
126:         $unionSql = implode(' UNION ', $unions);
127: 
128:         $this->pdo->exec('BEGIN IMMEDIATE');
129: 
130:         $stmt = $this->pdo->prepare($unionSql);
131:         $stmt->execute($args);
132:         $keys = $stmt->fetchAll(\PDO::FETCH_COLUMN, 0);
133: 
134:         if (empty($keys)) {
135:             $this->pdo->exec('COMMIT');
136:             return [];
137:         }
138: 
139:         $this->pdo->prepare("DELETE FROM tags WHERE key IN ($unionSql)")->execute($args);
140:         $this->pdo->prepare("DELETE FROM priorities WHERE key IN ($unionSql)")->execute($args);
141:         $this->pdo->exec('COMMIT');
142: 
143:         return $keys;
144:     }
145: }
146: