MWMemcached Class Reference

This is the PHP client for memcached - a distributed memory cache daemon. More...

Inheritance diagram for MWMemcached:

Collaboration diagram for MWMemcached:

List of all members.

Public Member Functions
	__construct ($args)
	Memcache initializer.
	_close_sock ($sock)
	Close the specified socket.
	_connect_sock (&$sock, $host)
	Connects $sock to $host, timing out after $timeout.
	_dead_host ($host)
	_dead_sock ($sock)
	Marks a host as dead until 30-40 seconds in the future.
	_debugprint ($text)
	_error_log ($text)
	_fgets ($sock)
	Read a line from a stream.
	_flush_read_buffer ($f)
	Flush the read buffer of a stream.
	_fread ($sock, $len)
	Read the specified number of bytes from a stream.
	_fwrite ($sock, $buf)
	Write to a stream.
	_handle_error ($sock, $msg)
	Handle an I/O error.
	_hashfunc ($key)
	Creates a hash integer based on the $key.
	_incrdecr ($cmd, $key, $amt=1)
	Perform increment/decriment on $key.
	_load_items ($sock, &$ret, &$casToken=null)
	Load items into $ret from $sock.
	_set ($cmd, $key, $val, $exp, $casToken=null)
	Performs the requested storage operation to the memcache server.
	add ($key, $val, $exp=0)
	Adds a key/value to the memcache server if one isn't already set with that key.
	cas ($casToken, $key, $value, $exp=0)
	Sets a key to a given value in the memcache if the current value still corresponds to a known, given value.
	decr ($key, $amt=1)
	Decrease a value stored on the memcache server.
	delete ($key, $time=0)
	Deletes a key from the server, optionally after $time.
	disconnect_all ()
	Disconnects all connected sockets.
	enable_compress ($enable)
	Enable / Disable compression.
	forget_dead_hosts ()
	Forget about all of the dead hosts.
	get ($key, &$casToken=null)
	Retrieves the value associated with the key from the memcache server.
	get_multi ($keys)
	Get multiple keys from the server(s)
	get_sock ($key)
	get_sock
	incr ($key, $amt=1)
	Increments $key (optionally) by $amt.
	lock ($key, $timeout=0)
	replace ($key, $value, $exp=0)
	Overwrites an existing value for key; only works if key is already set.
	run_command ($sock, $cmd)
	Passes through $cmd to the memcache server connected by $sock; returns output as an array (null array if no output)
	set ($key, $value, $exp=0)
	Unconditionally sets a key to a given value in the memcache.
	set_compress_threshold ($thresh)
	Sets the compression threshold.
	set_debug ($dbg)
	Sets the debug flag.
	set_servers ($list)
	Sets the server list to distribute key gets and puts between.
	set_timeout ($seconds, $microseconds)
	Sets the timeout for new connections.
	sock_to_host ($host)
	Returns the socket for the host.
	unlock ($key)
Public Attributes
integer	$_active
	# of total servers we have
integer	$_bucketcount
	Total # of bit buckets we have.
array	$_buckets
	Our bit buckets.
array	$_cache_sock
	Cached Sockets that are connected.
boolean	$_compress_enable
	Do we want to use compression?
integer	$_compress_threshold
	At how many bytes should we compress?
	$_connect_attempts
	Number of connection attempts for each server.
	$_connect_timeout
	Connect timeout in seconds.
boolean	$_debug
	Current debug status; 0 - none to 9 - profiling.
boolean	$_have_zlib
	Is compression available?
array	$_host_dead
	Dead hosts, assoc array, 'host'=>'unixtime when ok to check again'.
boolean	$_persistent
	Are we using persistent links?
array	$_servers
	Array containing ip:port or array(ip:port, weight)
string	$_single_sock
	If only using one server; contains ip:port to connect to.
integer	$_timeout_microseconds
	Stream timeout in microseconds.
integer	$_timeout_seconds
	Stream timeout in seconds.
array	$stats
	Command statistics.
const	COMPRESSED = 2
	Flag: indicates data is compressed.
const	COMPRESSION_SAVINGS = 0.20
	Minimum savings to store data compressed.
const	SERIALIZED = 1
	Flag: indicates data is serialized.

---

Detailed Description

This is the PHP client for memcached - a distributed memory cache daemon.

More information is available at http://www.danga.com/memcached/

Usage example:

require_once 'memcached.php';

$mc = new MWMemcached(array( 'servers' => array('127.0.0.1:10000', array('192.0.0.1:10010', 2), '127.0.0.1:10020'), 'debug' => false, 'compress_threshold' => 10240, 'persistent' => true));

$mc->add( 'key', array( 'some', 'array' ) ); $mc->replace( 'key', 'some random string' ); $val = $mc->get( 'key' );

Author:

Ryan T. Dean <[email protected]>

Version:

0.1.2 memcached client class implemented using (p)fsockopen()

Author:

Ryan T. Dean <[email protected]>

Definition at line 76 of file MemcachedClient.php.

---

Constructor & Destructor Documentation

MWMemcached::__construct

(

$

args

)

Memcache initializer.

Parameters:

array

$args

Associative array of settings

Returns:

mixed

Definition at line 233 of file MemcachedClient.php.

References array(), and set_servers().

---

Member Function Documentation

MWMemcached::_close_sock

(

$

sock

)

Close the specified socket.

Parameters:

string

$sock

socket to close

Access:

private

Definition at line 698 of file MemcachedClient.php.

MWMemcached::_connect_sock	(	&$	sock,
		$	host
	)

Connects $sock to $host, timing out after $timeout.

Parameters:

	$sock	Integer: socket to connect
string	$host	Host:IP to connect to

Returns:

boolean

Access:

private

Definition at line 716 of file MemcachedClient.php.

MWMemcached::_dead_host

(

$

host

)

Parameters:

$host

Definition at line 765 of file MemcachedClient.php.

MWMemcached::_dead_sock

(

$

sock

)

Marks a host as dead until 30-40 seconds in the future.

Parameters:

string

$sock

socket to mark as dead

Access:

private

Definition at line 757 of file MemcachedClient.php.

MWMemcached::_debugprint

(

$

text

)

Parameters:

$text

string

Definition at line 1090 of file MemcachedClient.php.

MWMemcached::_error_log

(

$

text

)

Parameters:

$text

string

Definition at line 1097 of file MemcachedClient.php.

MWMemcached::_fgets

(

$

sock

)

Read a line from a stream.

If there is an error, mark the socket dead. The
line ending is stripped from the response.

Parameters:

$sock

The socket

Returns:

The string on success, false on failure

Definition at line 1184 of file MemcachedClient.php.

MWMemcached::_flush_read_buffer

(

$

f

)

Flush the read buffer of a stream.

Parameters:

$f

Resource

Definition at line 1213 of file MemcachedClient.php.

References $result.

MWMemcached::_fread	(	$	sock,
		$	len
	)

Read the specified number of bytes from a stream.

If there is an error, mark the socket dead.

Parameters:

$sock	The socket
$len	The number of bytes to read

Returns:

The string on success, false on failure.

Definition at line 1153 of file MemcachedClient.php.

MWMemcached::_fwrite	(	$	sock,
		$	buf
	)

Write to a stream.

If there is an error, mark the socket dead.

Parameters:

$sock	The socket
$buf	The string to write

Returns:

bool True on success, false on failure

Definition at line 1108 of file MemcachedClient.php.

References wfDebugLog().

MWMemcached::_handle_error	(	$	sock,
		$	msg
	)

Handle an I/O error.

Mark the socket dead and log an error.

Definition at line 1132 of file MemcachedClient.php.

MWMemcached::_hashfunc

(

$

key

)

Creates a hash integer based on the $key.

Parameters:

string

$key

key to hash

Returns:

Integer: hash value

Access:

private

Definition at line 833 of file MemcachedClient.php.

MWMemcached::_incrdecr	(	$	cmd,
		$	key,
		$	amt = 1
	)

Perform increment/decriment on $key.

Parameters:

string	$cmd	command to perform
string | array	$key	key to perform it on
	$amt	Integer amount to adjust

Returns:

Integer: new value of $key

Access:

private

Definition at line 853 of file MemcachedClient.php.

Referenced by delete().

MWMemcached::_load_items	(	$	sock,
		&$	ret,
		&$	casToken = null
	)

Load items into $ret from $sock.

Parameters:

	$sock	Resource: socket to read from
array	$ret	returned values
	$casToken[optional]	Float

Returns:

boolean True for success, false for failure

Access:

private

Definition at line 894 of file MemcachedClient.php.

MWMemcached::_set	(	$	cmd,
		$	key,
		$	val,
		$	exp,
		$	casToken = null
	)

Performs the requested storage operation to the memcache server.

Parameters:

string	$cmd	command to perform
string	$key	key to act on
	$val	Mixed: what we need to store
	$exp	Integer: (optional) Expiration time. This can be a number of seconds to cache for (up to 30 days inclusive). Any timespans of 30 days + 1 second or longer must be the timestamp of the time at which the mapping should expire. It is safe to use timestamps in all cases, regardless of exipration eg: strtotime("+3 hour")
	$casToken[optional]	Float

Returns:

Boolean

Access:

private

Definition at line 986 of file MemcachedClient.php.

Referenced by decr(), and set().

MWMemcached::add	(	$	key,
		$	val,
		$	exp = 0
	)

Adds a key/value to the memcache server if one isn't already set with that key.

Parameters:

string	$key	key to set with data
	$val	Mixed: value to store
	$exp	Integer: (optional) Expiration time. This can be a number of seconds to cache for (up to 30 days inclusive). Any timespans of 30 days + 1 second or longer must be the timestamp of the time at which the mapping should expire. It is safe to use timestamps in all cases, regardless of expiration eg: strtotime("+3 hour")

Returns:

Boolean

Definition at line 269 of file MemcachedClient.php.

MWMemcached::cas	(	$	casToken,
		$	key,
		$	value,
		$	exp = 0
	)

Sets a key to a given value in the memcache if the current value still corresponds to a known, given value.

Returns true if set successfully.

Parameters:

	$casToken	Float: current known value
string	$key	key to set value as
	$value	Mixed: value to set
	$exp	Integer: (optional) Expiration time. This can be a number of seconds to cache for (up to 30 days inclusive). Any timespans of 30 days + 1 second or longer must be the timestamp of the time at which the mapping should expire. It is safe to use timestamps in all cases, regardless of exipration eg: strtotime("+3 hour")

Returns:

Boolean: TRUE on success

Definition at line 623 of file MemcachedClient.php.

MWMemcached::decr	(	$	key,
		$	amt = 1
	)

Decrease a value stored on the memcache server.

Parameters:

string	$key	key to decrease
	$amt	Integer: (optional) amount to decrease

Returns:

Mixed: FALSE on failure, value on success

Definition at line 284 of file MemcachedClient.php.

References $key, and _set().

MWMemcached::delete	(	$	key,
		$	time = 0
	)

Deletes a key from the server, optionally after $time.

Parameters:

string	$key	key to delete
	$time	Integer: (optional) how long to wait before deleting

Returns:

Boolean: TRUE on success, FALSE on failure

Definition at line 299 of file MemcachedClient.php.

References $key, and _incrdecr().

MWMemcached::disconnect_all

(

)

Disconnects all connected sockets.

Definition at line 358 of file MemcachedClient.php.

MWMemcached::enable_compress

(

$

enable

)

Enable / Disable compression.

Parameters:

$enable

Boolean: TRUE to enable, FALSE to disable

Definition at line 374 of file MemcachedClient.php.

MWMemcached::forget_dead_hosts

(

)

Forget about all of the dead hosts.

Definition at line 384 of file MemcachedClient.php.

MWMemcached::get	(	$	key,
		&$	casToken = null
	)

Retrieves the value associated with the key from the memcache server.

Parameters:

array | string	$key	key to retrieve
	$casToken[optional]	Float

Returns:

Mixed

Definition at line 399 of file MemcachedClient.php.

References array().

MWMemcached::get_multi

(

$

keys

)

Get multiple keys from the server(s)

Parameters:

array

$keys

keys to retrieve

Returns:

Array

Definition at line 458 of file MemcachedClient.php.

MWMemcached::get_sock

(

$

key

)

get_sock

Parameters:

string

$key

key to retrieve value for;

Returns:

Mixed: resource on success, false on failure

Access:

private

Definition at line 784 of file MemcachedClient.php.

MWMemcached::incr	(	$	key,
		$	amt = 1
	)

Increments $key (optionally) by $amt.

Parameters:

string	$key	key to increment
	$amt	Integer: (optional) amount to increment

Returns:

Integer: null if the key does not exist yet (this does NOT create new mappings if the key does not exist). If the key does exist, this returns the new value for that key.

Definition at line 525 of file MemcachedClient.php.

MWMemcached::lock	(	$	key,
		$	timeout = 0
	)

Parameters:

$key
$timeout	int

Returns:

bool

Definition at line 338 of file MemcachedClient.php.

MWMemcached::replace	(	$	key,
		$	value,
		$	exp = 0
	)

Overwrites an existing value for key; only works if key is already set.

Parameters:

string	$key	key to set value as
	$value	Mixed: value to store
	$exp	Integer: (optional) Expiration time. This can be a number of seconds to cache for (up to 30 days inclusive). Any timespans of 30 days + 1 second or longer must be the timestamp of the time at which the mapping should expire. It is safe to use timestamps in all cases, regardless of exipration eg: strtotime("+3 hour")

Returns:

Boolean

Definition at line 545 of file MemcachedClient.php.

MWMemcached::run_command	(	$	sock,
		$	cmd
	)

Passes through $cmd to the memcache server connected by $sock; returns output as an array (null array if no output)

Parameters:

	$sock	Resource: socket to send command on
string	$cmd	command to run

Returns:

Array: output array

Definition at line 561 of file MemcachedClient.php.

MWMemcached::set	(	$	key,
		$	value,
		$	exp = 0
	)

Unconditionally sets a key to a given value in the memcache.

Returns true if set successfully.

Parameters:

string	$key	key to set value as
	$value	Mixed: value to set
	$exp	Integer: (optional) Expiration time. This can be a number of seconds to cache for (up to 30 days inclusive). Any timespans of 30 days + 1 second or longer must be the timestamp of the time at which the mapping should expire. It is safe to use timestamps in all cases, regardless of exipration eg: strtotime("+3 hour")

Returns:

Boolean: TRUE on success

Definition at line 601 of file MemcachedClient.php.

References $value, and _set().

MWMemcached::set_compress_threshold

(

$

thresh

)

Sets the compression threshold.

Parameters:

$thresh

Integer: threshold to compress if larger than

Definition at line 635 of file MemcachedClient.php.

MWMemcached::set_debug

(

$

dbg

)

Sets the debug flag.

Parameters:

$dbg	Boolean: TRUE for debugging, FALSE otherwise

See also:

MWMemcached::__construct

Definition at line 649 of file MemcachedClient.php.

MWMemcached::set_servers

(

$

list

)

Sets the server list to distribute key gets and puts between.

Parameters:

array

$list

of servers to connect to

See also:

MWMemcached::__construct()

Definition at line 663 of file MemcachedClient.php.

Referenced by __construct().

MWMemcached::set_timeout	(	$	seconds,
		$	microseconds
	)

Sets the timeout for new connections.

Parameters:

$seconds	Integer: number of seconds
$microseconds	Integer: number of microseconds

Definition at line 681 of file MemcachedClient.php.

MWMemcached::sock_to_host

(

$

host

)

Returns the socket for the host.

Parameters:

string

$host

Host:IP to get socket for

Returns:

Mixed: IO Stream or false

Access:

private

Definition at line 1061 of file MemcachedClient.php.

MWMemcached::unlock

(

$

key

)

Parameters:

$key

Returns:

bool

Definition at line 347 of file MemcachedClient.php.

---

Member Data Documentation

integer MWMemcached::$_active

# of total servers we have

Access:

private

Definition at line 194 of file MemcachedClient.php.

integer MWMemcached::$_bucketcount

Total # of bit buckets we have.

Access:

private

Definition at line 187 of file MemcachedClient.php.

array MWMemcached::$_buckets

Our bit buckets.

Access:

private

Definition at line 180 of file MemcachedClient.php.

array MWMemcached::$_cache_sock

Cached Sockets that are connected.

Access:

private

Definition at line 117 of file MemcachedClient.php.

boolean MWMemcached::$_compress_enable

Do we want to use compression?

Access:

private

Definition at line 145 of file MemcachedClient.php.

integer MWMemcached::$_compress_threshold

At how many bytes should we compress?

Access:

private

Definition at line 152 of file MemcachedClient.php.

MWMemcached::$_connect_attempts

Number of connection attempts for each server.

Definition at line 218 of file MemcachedClient.php.

MWMemcached::$_connect_timeout

Connect timeout in seconds.

Definition at line 213 of file MemcachedClient.php.

boolean MWMemcached::$_debug

Current debug status; 0 - none to 9 - profiling.

Access:

private

Definition at line 124 of file MemcachedClient.php.

boolean MWMemcached::$_have_zlib

Is compression available?

Access:

private

Definition at line 138 of file MemcachedClient.php.

array MWMemcached::$_host_dead

Dead hosts, assoc array, 'host'=>'unixtime when ok to check again'.

Access:

private

Definition at line 131 of file MemcachedClient.php.

boolean MWMemcached::$_persistent

Are we using persistent links?

Access:

private

Definition at line 159 of file MemcachedClient.php.

array MWMemcached::$_servers

Array containing ip:port or array(ip:port, weight)

Access:

private

Definition at line 173 of file MemcachedClient.php.

string MWMemcached::$_single_sock

If only using one server; contains ip:port to connect to.

Access:

private

Definition at line 166 of file MemcachedClient.php.

integer MWMemcached::$_timeout_microseconds

Stream timeout in microseconds.

Access:

private

Definition at line 208 of file MemcachedClient.php.

integer MWMemcached::$_timeout_seconds

Stream timeout in seconds.

Applies for example to fread()

Access:

private

Definition at line 201 of file MemcachedClient.php.

array MWMemcached::$stats

Command statistics.

Access:

public

Definition at line 107 of file MemcachedClient.php.

const MWMemcached::COMPRESSED = 2

Flag: indicates data is compressed.

Definition at line 91 of file MemcachedClient.php.

const MWMemcached::COMPRESSION_SAVINGS = 0.20

Minimum savings to store data compressed.

Definition at line 98 of file MemcachedClient.php.

const MWMemcached::SERIALIZED = 1

Flag: indicates data is serialized.

Definition at line 86 of file MemcachedClient.php.

---

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

• includes/objectcache/MemcachedClient.php