Implementing Redis cache engine

lib/Cake/Cache/Engine/RedisEngine.php

@@ -0,0 +1,216 @@
+<?php
+/**
+ * Redis storage engine for cache
+ *
+ *
+ * PHP 5
+ *
+ * CakePHP(tm) : Rapid Development Framework (http://cakephp.org)
+ * Copyright 2005-2012, Cake Software Foundation, Inc. (http://cakefoundation.org)
+ *
+ * Licensed under The MIT License
+ * Redistributions of files must retain the above copyright notice.
+ *
+ * @copyright     Copyright 2005-2012, Cake Software Foundation, Inc. (http://cakefoundation.org)
+ * @link          http://cakephp.org CakePHP(tm) Project
+ * @package       Cake.Cache.Engine
+ * @since         CakePHP(tm) v 2.2
+ * @license       MIT License (http://www.opensource.org/licenses/mit-license.php)
+ */
+
+/**
+ * Redis storage engine for cache.
+ *
+ * @package       Cake.Cache.Engine
+ */
+class RedisEngine extends CacheEngine {
+
+/**
+ * Redis wrapper.
+ *
+ * @var Redis
+ */
+	protected $_Redis = null;
+
+/**
+ * Settings
+ *
+ *  - server = string url or ip to the Redis server host
+ *
+ * @var array
+ */
+	public $settings = array();
+
+/**
+ * Initialize the Cache Engine
+ *
+ * Called automatically by the cache frontend
+ * To reinitialize the settings call Cache::engine('EngineName', [optional] settings = array());
+ *
+ * @param array $settings array of setting for the engine
+ * @return boolean True if the engine has been successfully initialized, false if not
+ */
+	public function init($settings = array()) {
+		if (!class_exists('Redis')) {
+			return false;
+		}
+		parent::init(array_merge(array(
+			'engine' => 'Redis',
+			'prefix' => null,
+			'server' => '127.0.0.1',
+			'port' => null,
+			'persistent' => true,
+			'serialize' => true
+			), $settings)
+		);
+
+		return $this->_connect();
+	}
+
+/**
+ * Connects to a Redis server
+ *
+ * @return boolean True if Redis server was connected
+ */
+	protected function _connect() {
+		$return = false;
+		try {
+			$this->_Redis = new Redis();
+			if (empty($this->settings['persistent'])) {
+				$return  = $this->_Redis->connect($this->settings['server']);
+			} else {
+				$return  = $this->_Redis->pconnect($this->settings['server']);
+			}
+		} catch (RedisException $e) {
+			return false;
+		}
+		return $return;
+	}
+
+/**
+ * Write data for key into cache.
+ *
+ * @param string $key Identifier for the data
+ * @param mixed $value Data to be cached
+ * @param integer $duration How long to cache the data, in seconds
+ * @return boolean True if the data was successfully cached, false on failure
+ */
+	public function write($key, $value, $duration) {
+		if (!is_int($value)) {
+			$value = serialize($value);
+		}
+		if ($duration === 0) {
+			return $this->_Redis->set($key, $value);
+		}
+
+		return $this->_Redis->setex($key, $duration, $value);
+	}
+
+/**
+ * Read a key from the cache
+ *
+ * @param string $key Identifier for the data
+ * @return mixed The cached data, or false if the data doesn't exist, has expired, or if there was an error fetching it
+ */
+	public function read($key) {
+		$value = $this->_Redis->get($key);
+		if (is_numeric($value)) {
+			$value = (int) $value;
+		}
+		if ($value !== false && is_string($value)) {
+			$value = unserialize($value);
+		}
+		return $value;
+	}
+
+/**
+ * Increments the value of an integer cached key
+ *
+ * @param string $key Identifier for the data
+ * @param integer $offset How much to increment
+ * @return New incremented value, false otherwise
+ * @throws CacheException when you try to increment with compress = true
+ */
+	public function increment($key, $offset = 1) {
+		return (int) $this->_Redis->incrBy($key, $offset);
+	}
+
+/**
+ * Decrements the value of an integer cached key
+ *
+ * @param string $key Identifier for the data
+ * @param integer $offset How much to subtract
+ * @return New decremented value, false otherwise
+ * @throws CacheException when you try to decrement with compress = true
+ */
+	public function decrement($key, $offset = 1) {
+		return (int) $this->_Redis->decrBy($key, $offset);
+	}
+
+/**
+ * Delete a key from the cache
+ *
+ * @param string $key Identifier for the data
+ * @return boolean True if the value was successfully deleted, false if it didn't exist or couldn't be removed
+ */
+	public function delete($key) {
+		return $this->_Redis->delete($key) > 0;
+	}
+
+/**
+ * Delete all keys from the cache
+ *
+ * @param boolean $check
+ * @return boolean True if the cache was successfully cleared, false otherwise
+ */
+	public function clear($check) {
+		if ($check) {
+			return true;
+		}
+		$keys = $this->_Redis->getKeys($this->settings['prefix'] . '*');
+		$this->_Redis->del($keys);
+
+		return true;
+	}
+
+/**
+ * Returns the `group value` for each of the configured groups
+ * If the group initial value was not found, then it initializes
+ * the group accordingly.
+ *
+ * @return array
+ **/
+	public function groups() {
+		$result = array();
+		foreach ($this->settings['groups'] as $group) {
+			$value = $this->_Redis->get($this->settings['prefix'] . $group);
+			if (!$value) {
+				$value = 1;
+				$this->_Redis->set($this->settings['prefix'] . $group, $value);
+			}
+			$result[] = $group . $value;
+		}
+		return $result;
+	}
+
+/**
+ * Increments the group value to simulate deletion of all keys under a group
+ * old values will remain in storage until they expire.
+ *
+ * @return boolean success
+ **/
+	public function clearGroup($group) {
+		return (bool) $this->_Redis->incr($this->settings['prefix'] . $group);
+	}
+
+/**
+ * Disconnects from the redis server
+ *
+ * @return voind
+ **/
+	public function __destruct() {
+		if (!$this->settings['persistent']) {
+			$this->_Redis->close();
+		}
+	}
+}

lib/Cake/Test/Case/Cache/Engine/RedisEngineTest.php

@@ -0,0 +1,336 @@
+<?php
+/**
+ * RedisEngineTest file
+ *
+ * PHP 5
+ *
+ * CakePHP(tm) Tests <http://book.cakephp.org/view/1196/Testing>
+ * Copyright 2005-2012, Cake Software Foundation, Inc. (http://cakefoundation.org)
+ *
+ * Licensed under The MIT License
+ * Redistributions of files must retain the above copyright notice
+ *
+ * @copyright     Copyright 2005-2012, Cake Software Foundation, Inc. (http://cakefoundation.org)
+ * @link          http://book.cakephp.org/view/1196/Testing CakePHP(tm) Tests
+ * @package       Cake.Test.Case.Cache.Engine
+ * @since         CakePHP(tm) v 2.2
+ * @license       MIT License (http://www.opensource.org/licenses/mit-license.php)
+ */
+
+App::uses('Cache', 'Cache');
+App::uses('RedisEngine', 'Cache/Engine');
+
+/**
+ * RedisEngineTest class
+ *
+ * @package       Cake.Test.Case.Cache.Engine
+ */
+class RegisEngineTest extends CakeTestCase {
+
+/**
+ * setUp method
+ *
+ * @return void
+ */
+	public function setUp() {
+		$this->skipIf(!class_exists('Redis'), 'Redis is not installed or configured properly.');
+
+		$this->_cacheDisable = Configure::read('Cache.disable');
+		Configure::write('Cache.disable', false);
+		Cache::config('redis', array(
+			'engine' => 'Redis',
+			'prefix' => 'cake_',
+			'duration' => 3600
+		));
+	}
+
+/**
+ * tearDown method
+ *
+ * @return void
+ */
+	public function tearDown() {
+		Configure::write('Cache.disable', $this->_cacheDisable);
+		Cache::drop('');
+		Cache::drop('redis_groups');
+		Cache::drop('redis_helper');
+		Cache::config('default');
+	}
+
+/**
+ * testSettings method
+ *
+ * @return void
+ */
+	public function testSettings() {
+		$settings = Cache::settings('redis');
+		unset($settings['serialize'], $settings['path']);
+		$expecting = array(
+			'port' => null,
+			'prefix' => 'cake_',
+			'duration' => 3600,
+			'probability' => 100,
+			'groups' => array(),
+			'engine' => 'Redis',
+			'server' => '127.0.0.1',
+			'persistent' => true
+		);
+		$this->assertEquals($expecting, $settings);
+	}
+
+/**
+ * testConnect method
+ *
+ * @return void
+ */
+	public function testConnect() {
+		$Redis = new RedisEngine();
+		$this->assertTrue($Redis->init(Cache::settings('redis')));
+	}
+
+/**
+ * testReadAndWriteCache method
+ *
+ * @return void
+ */
+	public function testReadAndWriteCache() {
+		Cache::set(array('duration' => 1), null, 'redis');
+
+		$result = Cache::read('test', 'redis');
+		$expecting = '';
+		$this->assertEquals($expecting, $result);
+
+		$data = 'this is a test of the emergency broadcasting system';
+		$result = Cache::write('test', $data, 'redis');
+		$this->assertTrue($result);
+
+		$result = Cache::read('test', 'redis');
+		$expecting = $data;
+		$this->assertEquals($expecting, $result);
+
+		$data = array(1, 2, 3);
+		$this->assertTrue(Cache::write('array_data', $data, 'redis'));
+		$this->assertEquals($data, Cache::read('array_data', 'redis'));
+
+		Cache::delete('test', 'redis');
+	}
+
+/**
+ * testExpiry method
+ *
+ * @return void
+ */
+	public function testExpiry() {
+		Cache::set(array('duration' => 1), 'redis');
+
+		$result = Cache::read('test', 'redis');
+		$this->assertFalse($result);
+
+		$data = 'this is a test of the emergency broadcasting system';
+		$result = Cache::write('other_test', $data, 'redis');
+		$this->assertTrue($result);
+
+		sleep(2);
+		$result = Cache::read('other_test', 'redis');
+		$this->assertFalse($result);
+
+		Cache::set(array('duration' => "+1 second"), 'redis');
+
+		$data = 'this is a test of the emergency broadcasting system';
+		$result = Cache::write('other_test', $data, 'redis');
+		$this->assertTrue($result);
+
+		sleep(2);
+		$result = Cache::read('other_test', 'redis');
+		$this->assertFalse($result);
+
+		Cache::config('redis', array('duration' => '+1 second'));
+		sleep(2);
+
+		$result = Cache::read('other_test', 'redis');
+		$this->assertFalse($result);
+
+		Cache::config('redis', array('duration' => '+29 days'));
+		$data = 'this is a test of the emergency broadcasting system';
+		$result = Cache::write('long_expiry_test', $data, 'redis');
+		$this->assertTrue($result);
+
+		sleep(2);
+		$result = Cache::read('long_expiry_test', 'redis');
+		$expecting = $data;
+		$this->assertEquals($expecting, $result);
+
+		Cache::config('redis', array('duration' => 3600));
+	}
+
+/**
+ * testDeleteCache method
+ *
+ * @return void
+ */
+	public function testDeleteCache() {
+		$data = 'this is a test of the emergency broadcasting system';
+		$result = Cache::write('delete_test', $data, 'redis');
+		$this->assertTrue($result);
+
+		$result = Cache::delete('delete_test', 'redis');
+		$this->assertTrue($result);
+	}
+
+/**
+ * testDecrement method
+ *
+ * @return void
+ */
+	public function testDecrement() {
+		Cache::delete('test_decrement', 'redis');
+		$result = Cache::write('test_decrement', 5, 'redis');
+		$this->assertTrue($result);
+
+		$result = Cache::decrement('test_decrement', 1, 'redis');
+		$this->assertEquals(4, $result);
+
+		$result = Cache::read('test_decrement', 'redis');
+		$this->assertEquals(4, $result);
+
+		$result = Cache::decrement('test_decrement', 2, 'redis');
+		$this->assertEquals(2, $result);
+
+		$result = Cache::read('test_decrement', 'redis');
+		$this->assertEquals(2, $result);
+	}
+
+/**
+ * testIncrement method
+ *
+ * @return void
+ */
+	public function testIncrement() {
+		Cache::delete('test_increment', 'redis');
+		$result = Cache::increment('test_increment', 1, 'redis');
+		$this->assertEquals(1, $result);
+
+		$result = Cache::read('test_increment', 'redis');
+		$this->assertEquals(1, $result);
+
+		$result = Cache::increment('test_increment', 2, 'redis');
+		$this->assertEquals(3, $result);
+
+		$result = Cache::read('test_increment', 'redis');
+		$this->assertEquals(3, $result);
+	}
+
+
+/**
+ * test clearing redis.
+ *
+ * @return void
+ */
+	public function testClear() {
+		Cache::config('redis2', array(
+			'engine' => 'Redis',
+			'prefix' => 'cake2_',
+			'duration' => 3600
+		));
+
+		Cache::write('some_value', 'cache1', 'redis');
+		$result = Cache::clear(true, 'redis');
+		$this->assertTrue($result);
+		$this->assertEquals('cache1', Cache::read('some_value', 'redis'));
+
+		Cache::write('some_value', 'cache2', 'redis2');
+		$result = Cache::clear(false, 'redis');
+		$this->assertTrue($result);
+		$this->assertFalse(Cache::read('some_value', 'redis'));
+		$this->assertEquals('cache2', Cache::read('some_value', 'redis2'));
+
+		Cache::clear(false, 'redis2');
+	}
+
+/**
+ * test that a 0 duration can successfully write.
+ *
+ * @return void
+ */
+	public function testZeroDuration() {
+		Cache::config('redis', array('duration' => 0));
+		$result = Cache::write('test_key', 'written!', 'redis');
+
+		$this->assertTrue($result);
+		$result = Cache::read('test_key', 'redis');
+		$this->assertEquals('written!', $result);
+	}
+
+/**
+ * Tests that configuring groups for stored keys return the correct values when read/written
+ * Shows that altering the group value is equivalent to deleting all keys under the same
+ * group
+ *
+ * @return void
+ */
+	public function testGroupReadWrite() {
+		Cache::config('redis_groups', array(
+			'engine' => 'Redis',
+			'duration' => 3600,
+			'groups' => array('group_a', 'group_b'),
+			'prefix' => 'test_'
+		));
+		Cache::config('redis_helper', array(
+			'engine' => 'Redis',
+			'duration' => 3600,
+			'prefix' => 'test_'
+		));
+		$this->assertTrue(Cache::write('test_groups', 'value', 'redis_groups'));
+		$this->assertEquals('value', Cache::read('test_groups', 'redis_groups'));
+
+		Cache::increment('group_a', 1, 'redis_helper');
+		$this->assertFalse(Cache::read('test_groups', 'redis_groups'));
+		$this->assertTrue(Cache::write('test_groups', 'value2', 'redis_groups'));
+		$this->assertEquals('value2', Cache::read('test_groups', 'redis_groups'));
+
+		Cache::increment('group_b', 1, 'redis_helper');
+		$this->assertFalse(Cache::read('test_groups', 'redis_groups'));
+		$this->assertTrue(Cache::write('test_groups', 'value3', 'redis_groups'));
+		$this->assertEquals('value3', Cache::read('test_groups', 'redis_groups'));
+	}
+
+/**
+ * Tests that deleteing from a groups-enabled config is possible
+ *
+ * @return void
+ */
+	public function testGroupDelete() {
+		Cache::config('redis_groups', array(
+			'engine' => 'Redis',
+			'duration' => 3600,
+			'groups' => array('group_a', 'group_b')
+		));
+		$this->assertTrue(Cache::write('test_groups', 'value', 'redis_groups'));
+		$this->assertEquals('value', Cache::read('test_groups', 'redis_groups'));
+		$this->assertTrue(Cache::delete('test_groups', 'redis_groups'));
+
+		$this->assertFalse(Cache::read('test_groups', 'redis_groups'));
+	}
+
+/**
+ * Test clearing a cache group
+ *
+ * @return void
+ **/
+	public function testGroupClear() {
+		Cache::config('redis_groups', array(
+			'engine' => 'Redis',
+			'duration' => 3600,
+			'groups' => array('group_a', 'group_b')
+		));
+
+		$this->assertTrue(Cache::write('test_groups', 'value', 'redis_groups'));
+		$this->assertTrue(Cache::clearGroup('group_a', 'redis_groups'));
+		$this->assertFalse(Cache::read('test_groups', 'redis_groups'));
+
+		$this->assertTrue(Cache::write('test_groups', 'value2', 'redis_groups'));
+		$this->assertTrue(Cache::clearGroup('group_b', 'redis_groups'));
+		$this->assertFalse(Cache::read('test_groups', 'redis_groups'));
+	}
+
+}