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  • Bug fixes for general core bugs in 4.0.x will end 8 May 2023 (12 months).
  • Bug fixes for security issues in 4.0.x will end 13 November 2023 (18 months).
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The library file for the session cache store. This file is part of the session cache store, it contains the API for interacting with an instance of the store. This is used as a default cache store within the Cache API. It should never be deleted.

Copyright: 2012 Sam Hemelryk
License: http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
File Size: 595 lines (18 kb)
Included or required:0 times
Referenced: 1 time
Includes or requires: 0 files

Defines 2 classes

session_data_store:: (3 methods):
  register_store_id()
  flush_store_by_id()
  flush_store()

cachestore_session:: (28 methods):
  __construct()
  get_supported_features()
  supports_multiple_identifiers()
  get_supported_modes()
  are_requirements_met()
  is_supported_mode()
  initialise()
  is_initialised()
  get()
  get_many()
  set()
  set_many()
  has()
  has_all()
  has_any()
  delete()
  delete_many()
  purge()
  reduce_for_maxsize()
  can_add_instance()
  instance_deleted()
  initialise_test_instance()
  unit_test_configuration()
  my_name()
  check_ttl()
  find_all()
  find_by_prefix()
  store_supports_native_ttl()


Class: session_data_store  - X-Ref

The session data store class.

register_store_id($id)   X-Ref
Returns a static store by reference... REFERENCE SUPER IMPORTANT.

return: array
param: string $id

flush_store_by_id($id)   X-Ref
Flushes the data belong to the given store id.

param: string $id

flush_store()   X-Ref
Flushes the store of all data.


Class: cachestore_session  - X-Ref

The Session store class.

__construct($name, array $configuration = array()   X-Ref
Constructs the store instance.

Noting that this function is not an initialisation. It is used to prepare the store for use.
The store will be initialised when required and will be provided with a cache_definition at that time.

param: string $name
param: array $configuration

get_supported_features(array $configuration = array()   X-Ref
Returns the supported features as a combined int.

return: int
param: array $configuration

supports_multiple_identifiers()   X-Ref
Returns false as this store does not support multiple identifiers.
(This optional function is a performance optimisation; it must be
consistent with the value from get_supported_features.)

return: bool False

get_supported_modes(array $configuration = array()   X-Ref
Returns the supported modes as a combined int.

return: int
param: array $configuration

are_requirements_met()   X-Ref
Returns true if the store requirements are met.

return: bool

is_supported_mode($mode)   X-Ref
Returns true if the given mode is supported by this store.

return: bool
param: int $mode One of cache_store::MODE_*

initialise(cache_definition $definition)   X-Ref
Initialises the cache.

Once this has been done the cache is all set to be used.

param: cache_definition $definition

is_initialised()   X-Ref
Returns true once this instance has been initialised.

return: bool

get($key)   X-Ref
Retrieves an item from the cache store given its key.

return: mixed The data that was associated with the key, or false if the key did not exist.
param: string $key The key to retrieve

get_many($keys)   X-Ref
Retrieves several items from the cache store in a single transaction.

If not all of the items are available in the cache then the data value for those that are missing will be set to false.

return: array An array of items from the cache. There will be an item for each key, those that were not in the store will
param: array $keys The array of keys to retrieve

set($key, $data, $testmaxsize = true)   X-Ref
Sets an item in the cache given its key and data value.

return: bool True if the operation was a success false otherwise.
param: string $key The key to use.
param: mixed $data The data to set.
param: bool $testmaxsize If set to true then we test the maxsize arg and reduce if required. If this is set to false you will

set_many(array $keyvaluearray)   X-Ref
Sets many items in the cache in a single transaction.

return: int The number of items successfully set. It is up to the developer to check this matches the number of items
param: array $keyvaluearray An array of key value pairs. Each item in the array will be an associative array with two

has($key)   X-Ref
Checks if the store has a record for the given key and returns true if so.

return: bool
param: string $key

has_all(array $keys)   X-Ref
Returns true if the store contains records for all of the given keys.

return: bool
param: array $keys

has_any(array $keys)   X-Ref
Returns true if the store contains records for any of the given keys.

return: bool
param: array $keys

delete($key)   X-Ref
Deletes an item from the cache store.

return: bool Returns true if the operation was a success, false otherwise.
param: string $key The key to delete.

delete_many(array $keys)   X-Ref
Deletes several keys from the cache in a single action.

return: int The number of items successfully deleted.
param: array $keys The keys to delete

purge()   X-Ref
Purges the cache deleting all items within it.

return: boolean True on success. False otherwise.

reduce_for_maxsize()   X-Ref
Reduces the size of the array if maxsize has been hit.

This function reduces the size of the store reducing it by 10% of its maxsize.
It removes the oldest items in the store when doing this.
The reason it does this an doesn't use a least recently used system is purely the overhead such a system
requires. The current approach is focused on speed, MUC already adds enough overhead to static/session caches
and avoiding more is of benefit.

return: int

can_add_instance()   X-Ref
Returns true if the user can add an instance of the store plugin.

return: bool

instance_deleted()   X-Ref
Performs any necessary clean up when the store instance is being deleted.


initialise_test_instance(cache_definition $definition)   X-Ref
Generates an instance of the cache store that can be used for testing.

return: cachestore_session
param: cache_definition $definition

unit_test_configuration()   X-Ref
Generates the appropriate configuration required for unit testing.

return: array Array of unit test configuration data to be used by initialise().

my_name()   X-Ref
Returns the name of this instance.

return: string

check_ttl()   X-Ref
Removes expired elements.

return: int number of removed elements

find_all()   X-Ref
Finds all of the keys being stored in the cache store instance.

return: array

find_by_prefix($prefix)   X-Ref
Finds all of the keys whose keys start with the given prefix.

return: array An array of keys.
param: string $prefix

store_supports_native_ttl()   X-Ref
This store supports native TTL handling.

return: bool