- <?php
- * @file
- * Functions and interfaces for cache handling.
- */
-
- * Instantiates and statically caches the correct class for a cache bin.
- *
- * By default, this returns an instance of the BackdropDatabaseCache class.
- * Classes implementing BackdropCacheInterface can register themselves both as a
- * default implementation and for specific bins.
- *
- * @param $bin
- * The cache bin for which the cache object should be returned, defaults to
- * 'cache'.
- *
- * @return BackdropCacheInterface
- * The cache object associated with the specified bin.
- *
- * @see BackdropCacheInterface
- */
- function cache(string $bin = 'cache') {
-
-
- $bin = str_replace('cache_', '', $bin);
-
-
-
- static $cache_objects;
- if (!isset($cache_objects[$bin])) {
- $class = settings_get('cache_class_' . $bin);
- if (!isset($class)) {
- $class = settings_get('cache_default_class', 'BackdropDatabaseCache');
- }
- $cache_objects[$bin] = new $class($bin);
- }
- return $cache_objects[$bin];
- }
-
- * Returns data from the persistent cache.
- *
- * Data may be stored as either plain text or as serialized data. cache_get()
- * will automatically return unserialized objects and arrays.
- *
- * @param string $cid
- * The cache ID of the data to retrieve.
- * @param string $bin
- * The cache bin from which data should be retrieved. Valid core values are
- * "cache", "bootstrap", "field", "filter", "form", "menu", "page", "path",
- * "update", "views", and "views_data". Bin names may include the prefix of
- * "cache_", but it is stripped out before execution.
- *
- * @return
- * The cache or FALSE on failure.
- */
- function cache_get(string $cid, string $bin = 'cache') {
- return cache($bin)->get($cid);
- }
-
- * Returns data from the persistent cache when given an array of cache IDs.
- *
- * @param array $cids
- * An array of cache IDs for the data to retrieve. This is passed by
- * reference, and will have the IDs successfully returned from cache
- * removed.
- * @param string $bin
- * The cache bin from which data should be retrieved. Valid core values are
- * "cache", "bootstrap", "field", "filter", "form", "menu", "page", "path",
- * "update", "views", and "views_data". Bin names may include the prefix of
- * "cache_", but it is stripped out before execution
- *
- * @return
- * An array of the items successfully returned from cache indexed by cid.
- */
- function cache_get_multiple(array &$cids, string $bin = 'cache') {
- return cache($bin)->getMultiple($cids);
- }
-
- * Stores data in the persistent cache.
- *
- * The persistent cache is split up into several cache bins. In the default
- * cache implementation, each cache bin corresponds to a database table by the
- * same name. Other implementations might want to store several bins in data
- * structures that get flushed together. While it is not a problem for most
- * cache bins if the entries in them are flushed before their expire time, some
- * might break functionality or are extremely expensive to recalculate. The
- * other bins are expired automatically by core. Contributed modules can add
- * additional bins and get them expired automatically by implementing
- * hook_flush_caches().
- *
- * The reasons for having several bins are as follows:
- * - Smaller bins mean smaller database tables and allow for faster selects and
- * inserts.
- * - We try to put fast changing cache items and rather static ones into
- * different bins. The effect is that only the fast changing bins will need a
- * lot of writes to disk. The more static bins will also be better cacheable
- * with MySQL's query cache.
- *
- * @param string $cid
- * The cache ID of the data to store.
- * @param mixed $data
- * The data to store in the cache. Complex data types will be automatically
- * serialized before insertion. Strings will be stored as plain text and are
- * not serialized.
- * @param string $bin
- * The cache bin in which data should be stored. Valid core values are
- * "cache", "bootstrap", "field", "filter", "form", "menu", "page", "path",
- * "update", "views", and "views_data". Bin names may include the prefix of
- * "cache_", but it is stripped out before execution
- * @param int $expire
- * (optional) Controls the maximum lifetime of this cache entry. Note that
- * caches might be subject to clearing at any time, so this setting does not
- * guarantee a minimum lifetime. With this in mind, the cache should not be
- * used for data that must be kept during a cache clear, like sessions.
- *
- * Use one of the following values:
- * - CACHE_PERMANENT: Indicates that the item should never be removed unless
- * explicitly told to using cache_clear_all() with a cache ID.
- * - CACHE_TEMPORARY: Indicates that the item should be removed at the next
- * general cache wipe.
- * - A Unix timestamp: Indicates that the item should be kept at least until
- * the given time, after which it behaves like CACHE_TEMPORARY.
- *
- * @see cache_get()
- */
- function cache_set(string $cid, $data, string $bin = 'cache', int $expire = CACHE_PERMANENT) {
- return cache($bin)->set($cid, $data, $expire);
- }
-
- * Flushes all cache items in a bin.
- *
- * @param string $bin
- * The bin whose data should be emptied.
- */
- function cache_flush(string $bin) {
- return cache($bin)->flush();
- }
-
- * Clears data from the cache.
- *
- * If called with the arguments $cid and $bin set to NULL or omitted, then
- * expirable entries will be cleared from the page and layout bins, and the
- * $wildcard argument is ignored.
- *
- * @param string|array|NULL $cid
- * The cache ID or an array of cache IDs. Otherwise, all cache entries that
- * can expire are deleted.
- * @param string|NULL $bin
- * The cache bin whose data should be cleared. Mandatory argument if $cid is
- * set.
- * @param bool $wildcard
- * If TRUE, the $cid argument must contain a string value and cache IDs
- * starting with $cid are deleted in addition to the exact cache ID specified
- * by $cid. If $wildcard is TRUE and $cid is '*', the entire cache is emptied.
- *
- * The wildcard parameter is a legacy argument. If needing to do a full bin
- * flush, use cache_flush() instead. Prefix-based flushes are also
- * discouraged, as not all cache backends natively support wildcard
- * functionality.
- *
- * @see cache_flush()
- */
- function cache_clear_all($cid = NULL, string $bin = NULL, bool $wildcard = FALSE) {
-
- if (!isset($cid) && !isset($bin)) {
- cache('layout_path')->flush();
- cache('page')->flush();
- return;
- }
-
- if (!$wildcard) {
- if (is_null($cid)) {
- cache($bin)->garbageCollection();
- }
- else {
- is_array($cid) ? cache($bin)->deleteMultiple($cid) : cache($bin)->delete($cid);
- }
- }
- else {
- if ($cid === '*') {
- cache($bin)->flush();
- }
- else {
- cache($bin)->deletePrefix($cid);
- }
- }
- }
-
- * Checks if a cache bin is empty.
- *
- * A cache bin is considered empty if it does not contain any valid data for any
- * cache ID.
- *
- * @param string $bin
- * The cache bin to check.
- *
- * @return
- * TRUE if the cache bin specified is empty.
- */
- function cache_is_empty(string $bin) {
- return cache($bin)->isEmpty();
- }
-
- * Defines an interface for cache implementations.
- *
- * All cache implementations have to implement this interface.
- * BackdropDatabaseCache provides the default implementation, which can be
- * consulted as an example.
- *
- * To make Backdrop use your implementation for a certain cache bin, you have to
- * set a value in settings.php with the name of the cache bin as its key and the
- * name of your class as its value. For example, if your implementation of
- * BackdropCacheInterface was called MyCustomCache, the following line in
- * settings.php would make Backdrop use it for the 'cache_page' bin:
- * @code
- * $settings['cache_class_cache_page'] = 'MyCustomCache';
- * @endcode
- *
- * Additionally, you can register your cache implementation to be used by
- * default for all cache bins by setting the $settings['cache_default_class'] to
- * the name of your implementation of the BackdropCacheInterface, e.g.
- * @code
- * $settings['cache_default_class'] = 'MyCustomCache';
- * @endcode
- *
- * To implement a completely custom cache bin, use the same format:
- * @code
- * $settings['cache_class_custom_bin'] = 'MyCustomCache';
- * @endcode
- * To access your custom cache bin, specify the name of the bin when storing
- * or retrieving cached data:
- * @code
- * cache('custom_bin')->set($cid, $data, $expire);
- * cache('custom_bin')->get($cid, 'custom_bin');
- * @endcode
- *
- * @see cache()
- * @see BackdropDatabaseCache
- */
- interface BackdropCacheInterface {
-
-
- * Returns data from the persistent cache.
- *
- * Data may be stored as either plain text or as serialized data.
- * cache()->get() will automatically return unserialized objects and arrays.
- *
- * @param string $cid
- * The cache ID of the data to retrieve.
- *
- * @return
- * The cache or FALSE on failure.
- */
- function get(string $cid);
-
-
- * Returns data from the persistent cache when given an array of cache IDs.
- *
- * @param array $cids
- * An array of cache IDs for the data to retrieve. This is passed by
- * reference, and will have the IDs successfully returned from cache
- * removed.
- *
- * @return
- * An array of the items successfully returned from cache indexed by cid.
- */
- function getMultiple(array &$cids);
-
-
- * Stores data in the persistent cache.
- *
- * @param string $cid
- * The cache ID of the data to store.
- * @param mixed $data
- * The data to store in the cache. Complex data types will be automatically
- * serialized before insertion. Strings will be stored as plain text and not
- * serialized. Some storage engines only allow objects up to a maximum of
- * 1MB in size to be stored by default. When caching large arrays or
- * similar, take care to ensure $data does not exceed this size.
- * @param int $expire
- * (optional) Controls the maximum lifetime of this cache entry. Note that
- * caches might be subject to clearing at any time, so this setting does not
- * guarantee a minimum lifetime. With this in mind, the cache should not be
- * used for data that must be kept during a cache clear, like sessions.
- *
- * Use one of the following values:
- * - CACHE_PERMANENT: Indicates that the item should never be removed unless
- * explicitly told to using cache_clear_all() with a cache ID.
- * - CACHE_TEMPORARY: Indicates that the item should be removed at the next
- * general cache wipe.
- * - A Unix timestamp: Indicates that the item should be kept at least until
- * the given time, after which it behaves like CACHE_TEMPORARY.
- */
- function set(string $cid, $data, int $expire = CACHE_PERMANENT);
-
-
- * Deletes an item from the cache.
- *
- * @param string $cid
- * The cache ID to delete.
- */
- function delete(string $cid);
-
-
- * Deletes multiple items from the cache.
- *
- * @param array $cids
- * An array of $cids to delete.
- */
- function deleteMultiple(array $cids);
-
-
- * Deletes items from the cache using a wildcard prefix.
- *
- * @param string $prefix
- * A wildcard prefix.
- */
- function deletePrefix(string $prefix);
-
-
- * Flushes all cache items in a bin.
- */
- function flush();
-
-
- * Performs garbage collection on a cache bin. Removing expired items.
- */
- function garbageCollection();
-
-
- * Checks if a cache bin is empty.
- *
- * A cache bin is considered empty if it does not contain any valid data for
- * any cache ID.
- *
- * @return
- * TRUE if the cache bin specified is empty.
- */
- function isEmpty();
- }