/cache/stores/redis/lib.php
PHP | 494 lines | 190 code | 44 blank | 260 comment | 20 complexity | db9e6117aa211a599a9f6842d9047875 MD5 | raw file
- <?php
- // This file is part of Moodle - http://moodle.org/
- //
- // Moodle is free software: you can redistribute it and/or modify
- // it under the terms of the GNU General Public License as published by
- // the Free Software Foundation, either version 3 of the License, or
- // (at your option) any later version.
- //
- // Moodle is distributed in the hope that it will be useful,
- // but WITHOUT ANY WARRANTY; without even the implied warranty of
- // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- // GNU General Public License for more details.
- //
- // You should have received a copy of the GNU General Public License
- // along with Moodle. If not, see <http://www.gnu.org/licenses/>.
- /**
- * Redis Cache Store - Main library
- *
- * @package cachestore_redis
- * @copyright 2013 Adam Durana
- * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
- */
- defined('MOODLE_INTERNAL') || die();
- /**
- * Redis Cache Store
- *
- * To allow separation of definitions in Moodle and faster purging, each cache
- * is implemented as a Redis hash. That is a trade-off between having functionality of TTL
- * and being able to manage many caches in a single redis instance. Given the recommendation
- * not to use TTL if at all possible and the benefits of having many stores in Redis using the
- * hash configuration, the hash implementation has been used.
- *
- * @copyright 2013 Adam Durana
- * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
- */
- class cachestore_redis extends cache_store implements cache_is_key_aware, cache_is_lockable,
- cache_is_configurable, cache_is_searchable {
- /**
- * Name of this store.
- *
- * @var string
- */
- protected $name;
- /**
- * The definition hash, used for hash key
- *
- * @var string
- */
- protected $hash;
- /**
- * Flag for readiness!
- *
- * @var boolean
- */
- protected $isready = false;
- /**
- * Cache definition for this store.
- *
- * @var cache_definition
- */
- protected $definition = null;
- /**
- * Connection to Redis for this store.
- *
- * @var Redis
- */
- protected $redis;
- /**
- * Determines if the requirements for this type of store are met.
- *
- * @return bool
- */
- public static function are_requirements_met() {
- return class_exists('Redis');
- }
- /**
- * Determines if this type of store supports a given mode.
- *
- * @param int $mode
- * @return bool
- */
- public static function is_supported_mode($mode) {
- return ($mode === self::MODE_APPLICATION || $mode === self::MODE_SESSION);
- }
- /**
- * Get the features of this type of cache store.
- *
- * @param array $configuration
- * @return int
- */
- public static function get_supported_features(array $configuration = array()) {
- return self::SUPPORTS_DATA_GUARANTEE + self::DEREFERENCES_OBJECTS + self::IS_SEARCHABLE;
- }
- /**
- * Get the supported modes of this type of cache store.
- *
- * @param array $configuration
- * @return int
- */
- public static function get_supported_modes(array $configuration = array()) {
- return self::MODE_APPLICATION + self::MODE_SESSION;
- }
- /**
- * Constructs an instance of this type of store.
- *
- * @param string $name
- * @param array $configuration
- */
- public function __construct($name, array $configuration = array()) {
- $this->name = $name;
- if (!array_key_exists('server', $configuration) || empty($configuration['server'])) {
- return;
- }
- $prefix = !empty($configuration['prefix']) ? $configuration['prefix'] : '';
- $this->redis = $this->new_redis($configuration['server'], $prefix);
- }
- /**
- * Create a new Redis instance and
- * connect to the server.
- *
- * @param string $server The server connection string
- * @param string $prefix The key prefix
- * @return Redis
- */
- protected function new_redis($server, $prefix = '') {
- $redis = new Redis();
- $port = null;
- if (strpos($server, ':')) {
- $serverconf = explode(':', $server);
- $server = $serverconf[0];
- $port = $serverconf[1];
- }
- if ($redis->connect($server, $port)) {
- $redis->setOption(Redis::OPT_SERIALIZER, Redis::SERIALIZER_PHP);
- if (!empty($prefix)) {
- $redis->setOption(Redis::OPT_PREFIX, $prefix);
- }
- // Database setting option...
- $this->isready = $this->ping($redis);
- } else {
- $this->isready = false;
- }
- return $redis;
- }
- /**
- * See if we can ping Redis server
- *
- * @param Redis $redis
- * @return bool
- */
- protected function ping(Redis $redis) {
- try {
- if ($redis->ping() === false) {
- return false;
- }
- } catch (Exception $e) {
- return false;
- }
- return true;
- }
- /**
- * Get the name of the store.
- *
- * @return string
- */
- public function my_name() {
- return $this->name;
- }
- /**
- * Initialize the store.
- *
- * @param cache_definition $definition
- * @return bool
- */
- public function initialise(cache_definition $definition) {
- $this->definition = $definition;
- $this->hash = $definition->generate_definition_hash();
- return true;
- }
- /**
- * Determine if the store is initialized.
- *
- * @return bool
- */
- public function is_initialised() {
- return ($this->definition !== null);
- }
- /**
- * Determine if the store is ready for use.
- *
- * @return bool
- */
- public function is_ready() {
- return $this->isready;
- }
- /**
- * Get the value associated with a given key.
- *
- * @param string $key The key to get the value of.
- * @return mixed The value of the key, or false if there is no value associated with the key.
- */
- public function get($key) {
- return $this->redis->hGet($this->hash, $key);
- }
- /**
- * Get the values associated with a list of keys.
- *
- * @param array $keys The keys to get the values of.
- * @return array An array of the values of the given keys.
- */
- public function get_many($keys) {
- return $this->redis->hMGet($this->hash, $keys);
- }
- /**
- * Set the value of a key.
- *
- * @param string $key The key to set the value of.
- * @param mixed $value The value.
- * @return bool True if the operation succeeded, false otherwise.
- */
- public function set($key, $value) {
- return ($this->redis->hSet($this->hash, $key, $value) !== false);
- }
- /**
- * Set the values of many keys.
- *
- * @param array $keyvaluearray An array of key/value pairs. Each item in the array is an associative array
- * with two keys, 'key' and 'value'.
- * @return int The number of key/value pairs successfuly set.
- */
- public function set_many(array $keyvaluearray) {
- $pairs = [];
- foreach ($keyvaluearray as $pair) {
- $pairs[$pair['key']] = $pair['value'];
- }
- if ($this->redis->hMSet($this->hash, $pairs)) {
- return count($pairs);
- }
- return 0;
- }
- /**
- * Delete the given key.
- *
- * @param string $key The key to delete.
- * @return bool True if the delete operation succeeds, false otherwise.
- */
- public function delete($key) {
- return ($this->redis->hDel($this->hash, $key) > 0);
- }
- /**
- * Delete many keys.
- *
- * @param array $keys The keys to delete.
- * @return int The number of keys successfully deleted.
- */
- public function delete_many(array $keys) {
- // Redis needs the hash as the first argument, so we have to put it at the start of the array.
- array_unshift($keys, $this->hash);
- return call_user_func_array(array($this->redis, 'hDel'), $keys);
- }
- /**
- * Purges all keys from the store.
- *
- * @return bool
- */
- public function purge() {
- return ($this->redis->del($this->hash) !== false);
- }
- /**
- * Cleans up after an instance of the store.
- */
- public function instance_deleted() {
- $this->purge();
- $this->redis->close();
- unset($this->redis);
- }
- /**
- * Determines if the store has a given key.
- *
- * @see cache_is_key_aware
- * @param string $key The key to check for.
- * @return bool True if the key exists, false if it does not.
- */
- public function has($key) {
- return $this->redis->hExists($this->hash, $key);
- }
- /**
- * Determines if the store has any of the keys in a list.
- *
- * @see cache_is_key_aware
- * @param array $keys The keys to check for.
- * @return bool True if any of the keys are found, false none of the keys are found.
- */
- public function has_any(array $keys) {
- foreach ($keys as $key) {
- if ($this->has($key)) {
- return true;
- }
- }
- return false;
- }
- /**
- * Determines if the store has all of the keys in a list.
- *
- * @see cache_is_key_aware
- * @param array $keys The keys to check for.
- * @return bool True if all of the keys are found, false otherwise.
- */
- public function has_all(array $keys) {
- foreach ($keys as $key) {
- if (!$this->has($key)) {
- return false;
- }
- }
- return true;
- }
- /**
- * Tries to acquire a lock with a given name.
- *
- * @see cache_is_lockable
- * @param string $key Name of the lock to acquire.
- * @param string $ownerid Information to identify owner of lock if acquired.
- * @return bool True if the lock was acquired, false if it was not.
- */
- public function acquire_lock($key, $ownerid) {
- return $this->redis->setnx($key, $ownerid);
- }
- /**
- * Checks a lock with a given name and owner information.
- *
- * @see cache_is_lockable
- * @param string $key Name of the lock to check.
- * @param string $ownerid Owner information to check existing lock against.
- * @return mixed True if the lock exists and the owner information matches, null if the lock does not
- * exist, and false otherwise.
- */
- public function check_lock_state($key, $ownerid) {
- $result = $this->redis->get($key);
- if ($result === $ownerid) {
- return true;
- }
- if ($result === false) {
- return null;
- }
- return false;
- }
- /**
- * Finds all of the keys being used by this cache store instance.
- *
- * @return array of all keys in the hash as a numbered array.
- */
- public function find_all() {
- return $this->redis->hKeys($this->hash);
- }
- /**
- * Finds all of the keys whose keys start with the given prefix.
- *
- * @param string $prefix
- *
- * @return array List of keys that match this prefix.
- */
- public function find_by_prefix($prefix) {
- $return = [];
- foreach ($this->find_all() as $key) {
- if (strpos($key, $prefix) === 0) {
- $return[] = $key;
- }
- }
- return $return;
- }
- /**
- * Releases a given lock if the owner information matches.
- *
- * @see cache_is_lockable
- * @param string $key Name of the lock to release.
- * @param string $ownerid Owner information to use.
- * @return bool True if the lock is released, false if it is not.
- */
- public function release_lock($key, $ownerid) {
- if ($this->check_lock_state($key, $ownerid)) {
- return ($this->redis->del($key) !== false);
- }
- return false;
- }
- /**
- * Creates a configuration array from given 'add instance' form data.
- *
- * @see cache_is_configurable
- * @param stdClass $data
- * @return array
- */
- public static function config_get_configuration_array($data) {
- return array('server' => $data->server, 'prefix' => $data->prefix);
- }
- /**
- * Sets form data from a configuration array.
- *
- * @see cache_is_configurable
- * @param moodleform $editform
- * @param array $config
- */
- public static function config_set_edit_form_data(moodleform $editform, array $config) {
- $data = array();
- $data['server'] = $config['server'];
- $data['prefix'] = !empty($config['prefix']) ? $config['prefix'] : '';
- $editform->set_data($data);
- }
- /**
- * Creates an instance of the store for testing.
- *
- * @param cache_definition $definition
- * @return mixed An instance of the store, or false if an instance cannot be created.
- */
- public static function initialise_test_instance(cache_definition $definition) {
- if (!self::are_requirements_met()) {
- return false;
- }
- $config = get_config('cachestore_redis');
- if (empty($config->test_server)) {
- return false;
- }
- $cache = new cachestore_redis('Redis test', ['server' => $config->test_server]);
- $cache->initialise($definition);
- return $cache;
- }
- /**
- * Return configuration to use when unit testing.
- *
- * @return array
- */
- public static function unit_test_configuration() {
- global $DB;
- if (!self::are_requirements_met() || !self::ready_to_be_used_for_testing()) {
- throw new moodle_exception('TEST_CACHESTORE_REDIS_TESTSERVERS not configured, unable to create test configuration');
- }
- return ['server' => TEST_CACHESTORE_REDIS_TESTSERVERS,
- 'prefix' => $DB->get_prefix(),
- ];
- }
- /**
- * Returns true if this cache store instance is both suitable for testing, and ready for testing.
- *
- * When TEST_CACHESTORE_REDIS_TESTSERVERS is set, then we are ready to be use d for testing.
- *
- * @return bool
- */
- public static function ready_to_be_used_for_testing() {
- return defined('TEST_CACHESTORE_REDIS_TESTSERVERS');
- }
- }