core\session\redis Class Reference

Redis based session handler. More...

Inheritance diagram for core\session\redis:

Public Member Functions
	__construct ()
	Create new instance of handler.
	abort ()
	Release lock on the session without writing it.
	handler_close ()
	Close the session completely.
	handler_destroy ($id)
	Handle destroying a session.
	handler_gc ($maxlifetime)
	Garbage collect sessions.
	handler_open ($savepath, $sessionname)
	Update our session search path to include session name when opened.
	handler_read ($id)
	Read the session data from storage.
	handler_write ($id, $data)
	Write the serialized session data to our session store.
	init ()
	Init session handler.
	kill_all_sessions ()
	Kill all active sessions, the core sessions table is purged afterwards.
	kill_session ($sid)
	Kill one session, the session record is removed afterwards.
	requires_write_lock ()
	Has this session been opened with a writelock? Your handler should call this during start() if you support read-only sessions.
	session_exists ($sid)
	Check the backend contains data for this session id.
	set_requires_write_lock ($requireswritelock)
	This is called after init() and before start() to indicate whether the session opened should be writable or not.
	start ()
	Start the session.
	write_close ()
	Write the session and release lock.

Public Attributes
const	COMPRESSION_GZIP = 'gzip'
	Compressor: PHP GZip.
const	COMPRESSION_NONE = 'none'
	Compressor: none.
const	COMPRESSION_ZSTD = 'zstd'
	Compressor: PHP Zstandard.

Protected Member Functions
	lock_session ($id)
	Obtain a session lock so we are the only one using it at the moment.
	time ()
	Return the current time.
	unlock_session ($id)
	Unlock a session.

Protected Attributes
int	$acquiretimeout = 120
	$acquiretimeout how long to wait for session lock in seconds
int	$acquirewarn = null
	$acquirewarn how long before warning when waiting for a lock in seconds
string	$auth = ''
	$auth redis password
int	$compressor = self::COMPRESSION_NONE
	$compressor The compressor to use
Redis	$connection = null
	Connection.
int	$database = 0
	$database the Redis database to store sesions in
string	$host = ''
	$host save_path string
string	$lasthash = null
	$lasthash hash of the session data content
int	$lockexpire
	$lockexpire how long to wait in seconds before expiring the lock automatically so that other requests may continue execution, ignored if PECL redis is below version 2.2.0.
int	$lockretry = 100
	$lockretry how long to wait between session lock attempts in ms
array	$locks = array()
	$locks List of currently held locks by this page.
int	$port = 6379
	$port The port to connect to
array	$prefix = ''
	$servers list of servers parsed from save_path
boolean	$requireswritelock = false
	$requireswritelock does the session need and/or have a lock?
int	$serializer = Redis::SERIALIZER_PHP
	$serializer The serializer to use
array	$sslopts = []
	$sslopts SSL options, if applicable
int	$timeout
	$timeout How long sessions live before expiring.

Detailed Description

Redis based session handler.

The default Redis session handler does not handle locking in 2.2.7, so we have written a php session handler that uses locking. The places where locking is used was modeled from the memcached code that is used in Moodle https://github.com/php-memcached-dev/php-memcached/blob/master/php_memcached_session.c

Copyright

2016 Russell Smith

License

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

Member Function Documentation

abort()

core\session\handler::abort ( )

inherited

Release lock on the session without writing it.

May not be possible in older versions of PHP. If so, session may be written anyway so that any locks are released.

handler_close()

core\session\redis::handler_close

(

)

Close the session completely.

We also remove all locks we may have obtained that aren't expired.

Return values

bool	true on success. false on unable to unlock sessions.

handler_destroy()

core\session\redis::handler_destroy

(

$id

)

Handle destroying a session.

Parameters

string

$id

the session id to destroy.

Return values

bool	true if the session was deleted, false otherwise.

handler_gc()

core\session\redis::handler_gc

(

$maxlifetime

)

Garbage collect sessions.

We don't we any as Redis does it for us.

Parameters

integer

$maxlifetime

All sessions older than this should be removed.

Return values

bool	true, as Redis handles expiry for us.

handler_open()

core\session\redis::handler_open	(		$savepath,
			$sessionname )

Update our session search path to include session name when opened.

Parameters

string	$savepath	unused session save path. (ignored)
string	$sessionname	Session name for this session. (ignored)

Return values

bool	true always as we will succeed.

handler_read()

core\session\redis::handler_read

(

$id

)

Read the session data from storage.

Parameters

string

$id

The session id to read from storage.

Return values

string

The session data for PHP to process.

Exceptions

RedisException

when we are unable to talk to the Redis server.

handler_write()

core\session\redis::handler_write	(		$id,
			$data )

Write the serialized session data to our session store.

Parameters

string	$id	session id to write.
string	$data	session data

Return values

bool	true on write success, false on failure

init()

core\session\redis::init

(

)

Init session handler.

Reimplemented from core\session\handler.

kill_all_sessions()

core\session\redis::kill_all_sessions

(

)

Kill all active sessions, the core sessions table is purged afterwards.

Reimplemented from core\session\handler.

kill_session()

core\session\redis::kill_session

(

$sid

)

Kill one session, the session record is removed afterwards.

Parameters

string

$sid

Reimplemented from core\session\handler.

lock_session()

core\session\redis::lock_session ( $id )

protected

Obtain a session lock so we are the only one using it at the moment.

Parameters

string

$id

The session id to lock.

Return values

bool	true when session was locked, exception otherwise.

Exceptions

exception

When we are unable to obtain a session lock.

requires_write_lock()

core\session\handler::requires_write_lock ( )

inherited

Has this session been opened with a writelock? Your handler should call this during start() if you support read-only sessions.

Return values

bool	true if session is intended to have a write lock.

session_exists()

core\session\redis::session_exists

(

$sid

)

Check the backend contains data for this session id.

Note: this is intended to be called from manager\session_exists() only.

Parameters

string

$sid

Return values

bool	true if session found.

Reimplemented from core\session\handler.

set_requires_write_lock()

core\session\handler::set_requires_write_lock ( $requireswritelock )

inherited

This is called after init() and before start() to indicate whether the session opened should be writable or not.

This is intentionally captured even if your handler doesn't support non-locking sessions, so that behavior (upon session close) matches closely between handlers.

Parameters

bool

$requireswritelock

true if needs to be open for writing

start()

core\session\redis::start

(

)

Start the session.

Return values

bool

success

Reimplemented from core\session\handler.

time()

core\session\redis::time ( )

protected

Return the current time.

Return values

int	the current time as a unixtimestamp.

unlock_session()

core\session\redis::unlock_session ( $id )

protected

Unlock a session.

Parameters

string

$id

Session id to be unlocked.

write_close()

core\session\handler::write_close ( )

inherited

Write the session and release lock.

If the session was not intentionally opened with a write lock, then we will abort the session instead if able.

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

• lib/classes/session/redis.php