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Long Term Support Release
- Bug fixes for general core bugs in 4.1.x will end 13 November 2023 (12 months).
- Bug fixes for security issues in 4.1.x will end 10 November 2025 (36 months).
- PHP version: minimum PHP 7.4.0 Note: minimum PHP version has increased since Moodle 4.0. PHP 8.0.x is supported too.
/cache/classes/ -> helper.php (source)
Differences Between: [Versions 310 and 401] [Versions 311 and 401] [Versions 39 and 401] [Versions 400 and 401] [Versions 401 and 402] [Versions 401 and 403]
Cache helper class This file is part of Moodle's cache API, affectionately called MUC. It contains the components that are requried in order to use caching.
| Copyright: | 2012 Sam Hemelryk |
| License: | http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later |
| File Size: | 875 lines (36 kb) |
| Included or required: | 0 times |
| Referenced: | 0 times |
| Includes or requires: | 0 files |
Defines 1 class
cache_helper:: (33 methods):
ready_for_early_init()
instance()
__construct()
get_class_for_mode()
get_cache_stores()
initialise_cachestore_instances()
get_cachelock_for_store()
early_get_cache_plugins()
invalidate_by_definition()
invalidate_by_event()
purge_by_definition()
purge_by_event()
ensure_ready_for_stats()
get_definition_stat_id_and_mode()
record_cache_hit()
record_cache_miss()
record_cache_set()
get_stats()
purge_all()
purge_store()
purge_stores_used_by_definition()
get_definition_name()
hash_key()
update_definitions()
update_site_identifier()
get_site_identifier()
get_site_version()
cron()
clean_old_session_data()
get_stores_suitable_for_mode_default()
get_stores_suitable_for_definition()
warnings()
result_found()
Class: cache_helper - X-Ref
The cache helper class.The cache helper class provides common functionality to the cache API and is useful to developers within to interact with
the cache API in a general way.
| ready_for_early_init() X-Ref |
| Returns true if the cache API can be initialised before Moodle has finished initialising itself. This check is essential when trying to cache the likes of configuration information. It checks to make sure that the cache configuration file has been created which allows use to set up caching when ever is required. return: bool |
| instance() X-Ref |
| Returns an instance of the cache_helper. This is designed for internal use only and acts as a static store. return: cache_helper |
| __construct() X-Ref |
| Constructs an instance of the cache_helper class. Again for internal use only. |
| get_class_for_mode($mode) X-Ref |
| Returns the class for use as a cache loader for the given mode. param: int $mode One of cache_store::MODE_ return: string |
| get_cache_stores(cache_definition $definition) X-Ref |
| Returns the cache stores to be used with the given definition. param: cache_definition $definition return: array |
| initialise_cachestore_instances(array $stores, cache_definition $definition) X-Ref |
| Internal function for initialising an array of stores against a given cache definition. param: array $stores param: cache_definition $definition return: cache_store[] |
| get_cachelock_for_store(cache_store $store) X-Ref |
| Returns a cache_lock instance suitable for use with the store. param: cache_store $store return: cache_lock_interface |
| early_get_cache_plugins() X-Ref |
| Returns an array of plugins without using core methods. This function explicitly does NOT use core functions as it will in some circumstances be called before Moodle has finished initialising. This happens when loading configuration for instance. return: string |
| invalidate_by_definition($component, $area, array $identifiers = array() X-Ref |
| Invalidates a given set of keys from a given definition. param: string $component param: string $area param: array $identifiers param: array $keys return: boolean |
| invalidate_by_event($event, array $keys) X-Ref |
| Invalidates a given set of keys by means of an event. Events cannot determine what identifiers might need to be cleared. Event based purge and invalidation are only supported on caches without identifiers. param: string $event param: array $keys |
| purge_by_definition($component, $area, array $identifiers = array() X-Ref |
| Purges the cache for a specific definition. param: string $component param: string $area param: array $identifiers return: bool |
| purge_by_event($event) X-Ref |
| Purges a cache of all information on a given event. Events cannot determine what identifiers might need to be cleared. Event based purge and invalidation are only supported on caches without identifiers. param: string $event |
| ensure_ready_for_stats($store, $storeclass, $definition, $mode = cache_store::MODE_APPLICATION) X-Ref |
| Ensure that the stats array is ready to collect information for the given store and definition. param: string $store param: string $storeclass param: string $definition A string that identifies the definition. param: int $mode One of cache_store::MODE_*. Since 2.9. |
| get_definition_stat_id_and_mode($definition) X-Ref |
| Returns a string to describe the definition. This method supports the definition as a string due to legacy requirements. It is backwards compatible when a string is passed but is not accurate. param: cache_definition|string $definition return: string |
| record_cache_hit($store, $definition, int $hits = 1, int $readbytes = cache_store::IO_BYTES_NOT_SUPPORTED) X-Ref |
| Record a cache hit in the stats for the given store and definition. In Moodle 2.9 the $definition argument changed from accepting only a string to accepting a string or a cache_definition instance. It is preferable to pass a cache definition instance. In Moodle 3.9 the first argument changed to also accept a cache_store. param: string|cache_store $store param: cache_definition $definition You used to be able to pass a string here, however that is deprecated please pass the param: int $hits The number of hits to record (by default 1) param: int $readbytes Number of bytes read from the cache or cache_store::IO_BYTES_NOT_SUPPORTED |
| record_cache_miss($store, $definition, $misses = 1) X-Ref |
| Record a cache miss in the stats for the given store and definition. In Moodle 2.9 the $definition argument changed from accepting only a string to accepting a string or a cache_definition instance. It is preferable to pass a cache definition instance. In Moodle 3.9 the first argument changed to also accept a cache_store. param: string|cache_store $store param: cache_definition $definition You used to be able to pass a string here, however that is deprecated please pass the param: int $misses The number of misses to record (by default 1) |
| record_cache_set($store, $definition, int $sets = 1,int $writebytes = cache_store::IO_BYTES_NOT_SUPPORTED) X-Ref |
| Record a cache set in the stats for the given store and definition. In Moodle 2.9 the $definition argument changed from accepting only a string to accepting a string or a cache_definition instance. It is preferable to pass a cache definition instance. In Moodle 3.9 the first argument changed to also accept a cache_store. param: string|cache_store $store param: cache_definition $definition You used to be able to pass a string here, however that is deprecated please pass the param: int $sets The number of sets to record (by default 1) param: int $writebytes Number of bytes written to the cache or cache_store::IO_BYTES_NOT_SUPPORTED |
| get_stats() X-Ref |
| Return the stats collected so far. return: array |
| purge_all($usewriter = false) X-Ref |
| Purge all of the cache stores of all of their data. Think twice before calling this method. It will purge **ALL** caches regardless of whether they have been used recently or anything. This will involve full setup of the cache + the purge operation. On a site using caching heavily this WILL be painful. param: bool $usewriter If set to true the cache_config_writer class is used. This class is special as it avoids |
| purge_store($storename, cache_config $config = null) X-Ref |
| Purges a store given its name. param: string $storename param: cache_config $config return: bool |
| purge_stores_used_by_definition($component, $area) X-Ref |
| Purges all of the stores used by a definition. Unlike cache_helper::purge_by_definition this purges all of the data from the stores not just the data relating to the definition. This function is useful when you must purge a definition that requires setup but you don't want to set it up. param: string $component param: string $area |
| get_definition_name($definition) X-Ref |
| Returns the translated name of the definition. param: cache_definition $definition return: lang_string |
| hash_key($key, cache_definition $definition) X-Ref |
| Hashes a descriptive key to make it shorter and still unique. param: string|int $key param: cache_definition $definition return: string |
| update_definitions($coreonly = false) X-Ref |
| Finds all definitions and updates them within the cache config file. param: bool $coreonly If set to true only core definitions will be updated. |
| update_site_identifier($siteidentifier) X-Ref |
| Update the site identifier stored by the cache API. param: string $siteidentifier return: string The new site identifier. |
| get_site_identifier() X-Ref |
| Returns the site identifier. return: string |
| get_site_version() X-Ref |
| Returns the site version. return: string |
| cron() X-Ref |
| Runs cron routines for MUC. |
| clean_old_session_data($output = false) X-Ref |
| Cleans old session data from cache stores used for session based definitions. param: bool $output If set to true output will be given. |
| get_stores_suitable_for_mode_default() X-Ref |
| Returns an array of stores that would meet the requirements for every definition. These stores would be 100% suitable to map as defaults for cache modes. return: array[] An array of stores, keys are the store names. |
| get_stores_suitable_for_definition(cache_definition $definition) X-Ref |
| Returns stores suitable for use with a given definition. param: cache_definition $definition return: cache_store[] |
| warnings(array $stores = null) X-Ref |
| Returns an array of warnings from the cache API. The warning returned here are for things like conflicting store instance configurations etc. These get shown on the admin notifications page for example. param: array|null $stores An array of stores to get warnings for, or null for all. return: string[] |
| result_found($value) X-Ref |
| A helper to determine whether a result was found. This has been deemed required after people have been confused by the fact that [] == false. param: mixed $value return: bool |
