Moodle PHP Documentation 4.4
Moodle 4.4.1 (Build: 20240610) (db07c09afc5)
core_cache\local\administration_display_helper Class Reference

A cache helper for administration tasks. More...

Inheritance diagram for core_cache\local\administration_display_helper:
core_cache\administration_helper cache_helper

Public Member Functions

 __construct ()
 Please do not call constructor directly.
 
 action_addstore ()
 Performs the add store action.
 
 action_deletelock (string $action)
 Performs the delete lock action.
 
 action_deletestore (string $action)
 Performs the deletestore action.
 
 action_editdefinitionmapping ()
 Performs the edit definition mapping action.
 
 action_editdefinitionsharing ()
 Performs the edit definition sharing action.
 
 action_editmodemappings ()
 Performs the edit mode mappings action.
 
 action_editstore ()
 Performs the edit store action.
 
 action_newlockinstance ()
 Performs the new lock instance action.
 
 action_purge ()
 Performs the purge action.
 
 action_purgedefinition ()
 Performs the purge definition action.
 
 action_rescan_definition ()
 Performs the rescan definition action.
 
 generate_admin_page (\core_cache\output\renderer $renderer)
 Outputs the main admin page by generating it through the renderer.
 
 get_add_lock_form (string $plugin, array $lockplugin=null)
 Gets the form to use when adding a lock instance.
 
 get_add_store_form (string $plugin)
 Returns a form that can be used to add a store instance.
 
 get_addable_lock_options ()
 Returns an array of lock plugins for which we can add an instance.
 
 get_definition_actions (\context $context, array $definitionsummary)
 Returns all of the actions that can be performed on a definition.
 
 get_edit_store_form (string $plugin, string $store)
 Returns a form that can be used to edit a store instance.
 
 get_lock_configuration_from_data (string $plugin, stdClass $data)
 Gets configuration data from a new lock instance form.
 
 get_store_configuration_from_data (\stdClass $data)
 Processes the results of the add/edit instance form data for a plugin returning an array of config information suitable to store in configuration.
 
 get_store_instance_actions (string $name, array $storedetails)
 Returns all of the actions that can be performed on a store.
 
 get_store_plugin_actions (string $name, array $plugindetails)
 Returns all of the actions that can be performed on a plugin.
 
 get_usage (int $samplekeys)
 Gets usage information about the whole cache system.
 
 perform_cache_actions (string $action, array $forminfo)
 Handles the page actions, based on the parameter.
 

Static Public Member Functions

static clean_old_session_data ($output=false)
 Cleans old session data from cache stores used for session based definitions.
 
static cron ()
 Runs cron routines for MUC.
 
static early_get_cache_plugins ()
 Returns an array of plugins without using core methods.
 
static get_cache_stores (cache_definition $definition)
 Returns the cache stores to be used with the given definition.
 
static get_cachelock_for_store (cache_store $store)
 Returns a cache_lock instance suitable for use with the store.
 
static get_class_for_mode ($mode)
 Returns the class for use as a cache loader for the given mode.
 
static get_default_mode_stores ()
 Get the default stores for all modes.
 
static get_definition_name ($definition)
 Returns the translated name of the definition.
 
static get_definition_sharing_options (int $sharingoption, bool $isselectedoptions=true)
 Given a sharing option hash this function returns an array of strings that can be used to describe it.
 
static get_definition_store_options (string $component, string $area)
 Get an array of stores that are suitable to be used for a given definition.
 
static get_definition_summaries ()
 Returns an array about the definitions.
 
static get_lock_summaries ()
 Returns an array summarising the locks available in the system.
 
static get_site_identifier ()
 Returns the site identifier.
 
static get_site_version ()
 Returns the site version.
 
static get_stats ()
 Return the stats collected so far.
 
static get_store_instance_summaries ()
 Returns an array containing all of the information about stores a renderer needs.
 
static get_store_plugin_summaries ()
 Returns an array of information about plugins, everything a renderer needs.
 
static get_stores_suitable_for_definition (cache_definition $definition)
 Returns stores suitable for use with a given definition.
 
static get_stores_suitable_for_mode_default ()
 Returns an array of stores that would meet the requirements for every definition.
 
static hash_key ($key, cache_definition $definition)
 Hashes a descriptive key to make it shorter and still unique.
 
static invalidate_by_definition ($component, $area, array $identifiers=array(), $keys=array())
 Invalidates a given set of keys from a given definition.
 
static invalidate_by_event ($event, array $keys)
 Invalidates a given set of keys by means of an event.
 
static is_cluster_available ()
 Checks whether the cluster mode is available in PHP.
 
static purge_all ($usewriter=false)
 Purge all of the cache stores of all of their data.
 
static purge_by_definition ($component, $area, array $identifiers=array())
 Purges the cache for a specific definition.
 
static purge_by_event ($event)
 Purges a cache of all information on a given event.
 
static purge_store ($storename, cache_config $config=null)
 Purges a store given its name.
 
static purge_stores_used_by_definition ($component, $area)
 Purges all of the stores used by a definition.
 
static ready_for_early_init ()
 Returns true if the cache API can be initialised before Moodle has finished initialising itself.
 
static record_cache_hit ($store, $definition, int $hits=1, int $readbytes=cache_store::IO_BYTES_NOT_SUPPORTED)
 Record a cache hit in the stats for the given store and definition.
 
static record_cache_miss ($store, $definition, $misses=1)
 Record a cache miss in the stats for the given store and definition.
 
static record_cache_set ($store, $definition, int $sets=1, int $writebytes=cache_store::IO_BYTES_NOT_SUPPORTED)
 Record a cache set in the stats for the given store and definition.
 
static result_found ($value)
 A helper to determine whether a result was found.
 
static update_definitions ($coreonly=false)
 Finds all definitions and updates them within the cache config file.
 
static update_site_identifier ($siteidentifier)
 Update the site identifier stored by the cache API.
 
static warnings (array $stores=null)
 Returns an array of warnings from the cache API.
 

Protected Member Functions

 get_possible_locks_for_stores (string $plugindir, string $plugin)
 Returns an array of suitable lock instances for use with this plugin, or false if the plugin handles locking itself.
 

Static Protected Member Functions

static ensure_ready_for_stats ($store, $storeclass, $definition, $mode=cache_store::MODE_APPLICATION)
 Ensure that the stats array is ready to collect information for the given store and definition.
 
static get_definition_stat_id_and_mode ($definition)
 Returns a string to describe the definition.
 
static initialise_cachestore_instances (array $stores, cache_definition $definition)
 Internal function for initialising an array of stores against a given cache definition.
 
static instance ()
 Returns an instance of the cache_helper.
 

Protected Attributes

array $definitions = array()
 Used as a data store for initialised definitions.
 
array $stores = array()
 Used as a data store for initialised cache stores We use this because we want to avoid establishing multiple instances of a single store.
 

Static Protected Attributes

static cache_helper $instance
 The instance of the cache helper.
 
static string $siteidentifier = null
 The site identifier used by the cache.
 
static array $stats = array()
 Statistics gathered by the cache API during its operation will be used here.
 

Detailed Description

A cache helper for administration tasks.

License
http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later

Constructor & Destructor Documentation

◆ __construct()

core_cache\local\administration_display_helper::__construct ( )

Please do not call constructor directly.

Use cache_factory\get_administration_display_helper() instead.

Reimplemented from cache_helper.

Member Function Documentation

◆ action_addstore()

core_cache\local\administration_display_helper::action_addstore ( )

Performs the add store action.

Return values
arrayan array of the form to display to the user, and the page title.

◆ action_deletelock()

core_cache\local\administration_display_helper::action_deletelock ( string $action)

Performs the delete lock action.

Parameters
string$actionthe action calling this function.

◆ action_deletestore()

core_cache\local\administration_display_helper::action_deletestore ( string $action)

Performs the deletestore action.

Parameters
string$actionthe action calling to this function.

◆ action_editdefinitionmapping()

core_cache\local\administration_display_helper::action_editdefinitionmapping ( )

Performs the edit definition mapping action.

Return values
arrayan array of the form to display, and the page title.
Exceptions
cache_exception

◆ action_editdefinitionsharing()

core_cache\local\administration_display_helper::action_editdefinitionsharing ( )

Performs the edit definition sharing action.

Return values
arrayan array of the edit definition sharing form, and the page title.

◆ action_editmodemappings()

core_cache\local\administration_display_helper::action_editmodemappings ( )

Performs the edit mode mappings action.

Return values
arrayan array of the edit mode mappings form.

◆ action_editstore()

core_cache\local\administration_display_helper::action_editstore ( )

Performs the edit store action.

Return values
arrayan array of the form to display, and the page title.

◆ action_newlockinstance()

core_cache\local\administration_display_helper::action_newlockinstance ( )

Performs the new lock instance action.

Return values
arrayAn array containing the new lock instance form.

◆ action_purge()

core_cache\local\administration_display_helper::action_purge ( )

Performs the purge action.

Return values
void

◆ action_purgedefinition()

core_cache\local\administration_display_helper::action_purgedefinition ( )

Performs the purge definition action.

Return values
void

◆ action_rescan_definition()

core_cache\local\administration_display_helper::action_rescan_definition ( )

Performs the rescan definition action.

Return values
void

◆ clean_old_session_data()

static cache_helper::clean_old_session_data ( $output = false)
staticinherited

Cleans old session data from cache stores used for session based definitions.

Parameters
bool$outputIf set to true output will be given.

◆ early_get_cache_plugins()

static cache_helper::early_get_cache_plugins ( )
staticinherited

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 values
array

◆ ensure_ready_for_stats()

static cache_helper::ensure_ready_for_stats ( $store,
$storeclass,
$definition,
$mode = cache_store::MODE_APPLICATION )
staticprotectedinherited

Ensure that the stats array is ready to collect information for the given store and definition.

Parameters
string$store
string$storeclass
string$definitionA string that identifies the definition.
int$modeOne of cache_store\MODE_*. Since 2.9.

◆ generate_admin_page()

core_cache\local\administration_display_helper::generate_admin_page ( \core_cache\output\renderer $renderer)

Outputs the main admin page by generating it through the renderer.

Parameters
core_cache\output\renderer$rendererthe renderer to use to generate the page.
Return values
stringthe HTML for the admin page.

Reimplemented from core_cache\administration_helper.

◆ get_add_lock_form()

core_cache\local\administration_display_helper::get_add_lock_form ( string $plugin,
array $lockplugin = null )

Gets the form to use when adding a lock instance.

Parameters
string$plugin
array$lockplugin
Return values
cache_lock_form
Exceptions
coding_exception

◆ get_add_store_form()

core_cache\local\administration_display_helper::get_add_store_form ( string $plugin)

Returns a form that can be used to add a store instance.

Parameters
string$pluginThe plugin to add an instance of
Return values
cachestore_addinstance_form
Exceptions
coding_exception

◆ get_addable_lock_options()

core_cache\local\administration_display_helper::get_addable_lock_options ( )

Returns an array of lock plugins for which we can add an instance.

Suitable for use within an mform select element.

Return values
array

Reimplemented from core_cache\administration_helper.

◆ get_cache_stores()

static cache_helper::get_cache_stores ( cache_definition $definition)
staticinherited

Returns the cache stores to be used with the given definition.

Parameters
cache_definition$definition
Return values
array

◆ get_cachelock_for_store()

static cache_helper::get_cachelock_for_store ( cache_store $store)
staticinherited

Returns a cache_lock instance suitable for use with the store.

Parameters
cache_store$store
Return values
cache_lock_interface

◆ get_class_for_mode()

static cache_helper::get_class_for_mode ( $mode)
staticinherited

Returns the class for use as a cache loader for the given mode.

Parameters
int$modeOne of cache_store\MODE_
Return values
string
Exceptions
coding_exception

◆ get_default_mode_stores()

static core_cache\administration_helper::get_default_mode_stores ( )
staticinherited

Get the default stores for all modes.

Return values
arrayAn array containing sub-arrays, one for each mode.

◆ get_definition_actions()

core_cache\local\administration_display_helper::get_definition_actions ( \context $context,
array $definitionsummary )

Returns all of the actions that can be performed on a definition.

Parameters
context$contextthe system context.
array$definitionsummaryinformation about this cache, from the array returned by core_cache\administration_helper\get_definition_summaries(). Currently only 'sharingoptions' element is used.
Return values
arrayof actions. Each action is an action_url.

Reimplemented from core_cache\administration_helper.

◆ get_definition_name()

static cache_helper::get_definition_name ( $definition)
staticinherited

Returns the translated name of the definition.

Parameters
cache_definition$definition
Return values
lang_string

◆ get_definition_sharing_options()

static core_cache\administration_helper::get_definition_sharing_options ( int $sharingoption,
bool $isselectedoptions = true )
staticinherited

Given a sharing option hash this function returns an array of strings that can be used to describe it.

Parameters
int$sharingoptionThe sharing option hash to get strings for.
bool$isselectedoptionsSet to true if the strings will be used to view the selected options.
Return values
arrayAn array of lang_string's.

◆ get_definition_stat_id_and_mode()

static cache_helper::get_definition_stat_id_and_mode ( $definition)
staticprotectedinherited

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.

Since
2.9
Parameters
cache_definition | string$definition
Return values
string

◆ get_definition_store_options()

static core_cache\administration_helper::get_definition_store_options ( string $component,
string $area )
staticinherited

Get an array of stores that are suitable to be used for a given definition.

Parameters
string$component
string$area
Return values
arrayArray containing 3 elements
  1. An array of currently used stores
  2. An array of suitable stores
  3. An array of default stores

◆ get_definition_summaries()

static core_cache\administration_helper::get_definition_summaries ( )
staticinherited

Returns an array about the definitions.

All the information a renderer needs.

Return values
arrayfor each store, an array containing various information about each store. See the code below for details

◆ get_edit_store_form()

core_cache\local\administration_display_helper::get_edit_store_form ( string $plugin,
string $store )

Returns a form that can be used to edit a store instance.

Parameters
string$plugin
string$store
Return values
cachestore_addinstance_form
Exceptions
coding_exception

◆ get_lock_configuration_from_data()

core_cache\local\administration_display_helper::get_lock_configuration_from_data ( string $plugin,
stdClass $data )

Gets configuration data from a new lock instance form.

Parameters
string$plugin
stdClass$data
Return values
array
Exceptions
coding_exception

◆ get_lock_summaries()

static core_cache\administration_helper::get_lock_summaries ( )
staticinherited

Returns an array summarising the locks available in the system.

Return values
arrayarray of lock summaries.

◆ get_possible_locks_for_stores()

core_cache\local\administration_display_helper::get_possible_locks_for_stores ( string $plugindir,
string $plugin )
protected

Returns an array of suitable lock instances for use with this plugin, or false if the plugin handles locking itself.

Parameters
string$plugindir
string$plugin
Return values
array|false

◆ get_site_identifier()

static cache_helper::get_site_identifier ( )
staticinherited

Returns the site identifier.

Return values
string

◆ get_site_version()

static cache_helper::get_site_version ( )
staticinherited

Returns the site version.

Return values
string

◆ get_stats()

static cache_helper::get_stats ( )
staticinherited

Return the stats collected so far.

Return values
array

◆ get_store_configuration_from_data()

core_cache\local\administration_display_helper::get_store_configuration_from_data ( \stdClass $data)

Processes the results of the add/edit instance form data for a plugin returning an array of config information suitable to store in configuration.

Parameters
stdClass$dataThe mform data.
Return values
array
Exceptions
coding_exception

◆ get_store_instance_actions()

core_cache\local\administration_display_helper::get_store_instance_actions ( string $name,
array $storedetails )

Returns all of the actions that can be performed on a store.

Parameters
string$nameThe name of the store
array$storedetailsinformation about this store, from the array returned by core_cache\administration_helper\get_store_instance_summaries().
Return values
arrayof actions. Each action is an action_url.

Reimplemented from core_cache\administration_helper.

◆ get_store_instance_summaries()

static core_cache\administration_helper::get_store_instance_summaries ( )
staticinherited

Returns an array containing all of the information about stores a renderer needs.

Return values
array

◆ get_store_plugin_actions()

core_cache\local\administration_display_helper::get_store_plugin_actions ( string $name,
array $plugindetails )

Returns all of the actions that can be performed on a plugin.

Parameters
string$nameThe name of the plugin
array$plugindetailsinformation about this store, from the array returned by core_cache\administration_helper\get_store_plugin_summaries().
Return values
arrayof actions. Each action is an action_url.

Reimplemented from core_cache\administration_helper.

◆ get_store_plugin_summaries()

static core_cache\administration_helper::get_store_plugin_summaries ( )
staticinherited

Returns an array of information about plugins, everything a renderer needs.

Return values
arrayfor each store, an array containing various information about each store. See the code below for details

◆ get_stores_suitable_for_definition()

static cache_helper::get_stores_suitable_for_definition ( cache_definition $definition)
staticinherited

Returns stores suitable for use with a given definition.

Parameters
cache_definition$definition
Return values
cache_store[]

◆ get_stores_suitable_for_mode_default()

static cache_helper::get_stores_suitable_for_mode_default ( )
staticinherited

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 values
array[]An array of stores, keys are the store names.

◆ get_usage()

core_cache\local\administration_display_helper::get_usage ( int $samplekeys)

Gets usage information about the whole cache system.

This is a slow function and should only be used on an admin information page.

The returned array lists all cache definitions with fields 'cacheid' and 'stores'. For each store, the following fields are available:

  • name (store name)
  • class (e.g. cachestore_redis)
  • supported (true if we have any information)
  • items (number of items stored)
  • mean (mean size of item)
  • sd (standard deviation for item sizes)
  • margin (margin of error for mean at 95% confidence)
  • storetotal (total usage for store if known, otherwise null)

The storetotal field will be the same for every cache that uses the same store.

Parameters
int$samplekeysNumber of keys to sample when checking size of large caches
Return values
arrayDetails of cache usage

Reimplemented from core_cache\administration_helper.

◆ hash_key()

static cache_helper::hash_key ( $key,
cache_definition $definition )
staticinherited

Hashes a descriptive key to make it shorter and still unique.

Parameters
string | int$key
cache_definition$definition
Return values
string

◆ initialise_cachestore_instances()

static cache_helper::initialise_cachestore_instances ( array $stores,
cache_definition $definition )
staticprotectedinherited

Internal function for initialising an array of stores against a given cache definition.

Parameters
array$stores
cache_definition$definition
Return values
cache_store[]

◆ instance()

static cache_helper::instance ( )
staticprotectedinherited

Returns an instance of the cache_helper.

This is designed for internal use only and acts as a static store. @staticvar null $instance

Return values
cache_helper

◆ invalidate_by_definition()

static cache_helper::invalidate_by_definition ( $component,
$area,
array $identifiers = array(),
$keys = array() )
staticinherited

Invalidates a given set of keys from a given definition.

Todo
Invalidating by definition should also add to the event cache so that sessions can be invalidated (when required).
Parameters
string$component
string$area
array$identifiers
array | string | int$keys
Return values
boolean
Exceptions
coding_exception

◆ invalidate_by_event()

static cache_helper::invalidate_by_event ( $event,
array $keys )
staticinherited

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.

Parameters
string$event
array$keys

◆ is_cluster_available()

static cache_helper::is_cluster_available ( )
staticinherited

Checks whether the cluster mode is available in PHP.

Return values
boolReturn true if the PHP supports redis cluster, otherwise false.

◆ perform_cache_actions()

core_cache\local\administration_display_helper::perform_cache_actions ( string $action,
array $forminfo )

Handles the page actions, based on the parameter.

Parameters
string$actionthe action to handle.
array$forminfoan empty array to be overridden and set.
Return values
arraythe empty or overridden forminfo array.

Reimplemented from core_cache\administration_helper.

◆ purge_all()

static cache_helper::purge_all ( $usewriter = false)
staticinherited

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.

Parameters
bool$usewriterIf set to true the cache_config_writer class is used. This class is special as it avoids it is still usable when caches have been disabled. Please use this option only if you really must. It's purpose is to allow the cache to be purged when it would be otherwise impossible.

◆ purge_by_definition()

static cache_helper::purge_by_definition ( $component,
$area,
array $identifiers = array() )
staticinherited

Purges the cache for a specific definition.

Parameters
string$component
string$area
array$identifiers
Return values
bool

◆ purge_by_event()

static cache_helper::purge_by_event ( $event)
staticinherited

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.

Parameters
string$event

◆ purge_store()

static cache_helper::purge_store ( $storename,
cache_config $config = null )
staticinherited

Purges a store given its name.

Parameters
string$storename
cache_config$config
Return values
bool

◆ purge_stores_used_by_definition()

static cache_helper::purge_stores_used_by_definition ( $component,
$area )
staticinherited

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.

Parameters
string$component
string$area

◆ ready_for_early_init()

static cache_helper::ready_for_early_init ( )
staticinherited

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 values
bool

◆ record_cache_hit()

static cache_helper::record_cache_hit ( $store,
$definition,
int $hits = 1,
int $readbytes = cache_store::IO_BYTES_NOT_SUPPORTED )
staticinherited

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.

◆ record_cache_miss()

static cache_helper::record_cache_miss ( $store,
$definition,
$misses = 1 )
staticinherited

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.

◆ record_cache_set()

static cache_helper::record_cache_set ( $store,
$definition,
int $sets = 1,
int $writebytes = cache_store::IO_BYTES_NOT_SUPPORTED )
staticinherited

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.

◆ result_found()

static cache_helper::result_found ( $value)
staticinherited

A helper to determine whether a result was found.

This has been deemed required after people have been confused by the fact that [] == false.

Parameters
mixed$value
Return values
bool

◆ update_definitions()

static cache_helper::update_definitions ( $coreonly = false)
staticinherited

Finds all definitions and updates them within the cache config file.

Parameters
bool$coreonlyIf set to true only core definitions will be updated.

◆ update_site_identifier()

static cache_helper::update_site_identifier ( $siteidentifier)
staticinherited

Update the site identifier stored by the cache API.

Parameters
string$siteidentifier
Return values
stringThe new site identifier.

◆ warnings()

static cache_helper::warnings ( array $stores = null)
staticinherited

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.

Parameters
array | null$storesAn array of stores to get warnings for, or null for all.
Return values
string[]

Member Data Documentation

◆ $siteidentifier

string cache_helper::$siteidentifier = null
staticprotectedinherited

The site identifier used by the cache.

Set the first time get_site_identifier is called.


The documentation for this class was generated from the following file: