Class MemcachedEngine

Memcached storage engine for cache. Memcached has some limitations in the amount of control you have over expire times far in the future. See MemcachedEngine::write() for more information.

Memcached engine supports binary protocol and igbinary serialization (if memcached extension is compiled with --enable-igbinary). Compressed keys can also be incremented/decremented.

Namespace: Cake\Cache\Engine

Property Summary

$_Memcached protected

Memcached

memcached wrapper.
$_compiledGroupNames protected

string[]
$_config protected

array

Runtime config
$_configInitialized protected

bool

Whether the config property has already been configured with defaults
$_defaultConfig protected

array

The default config used unless overridden by runtime configuration
$_groupPrefix protected

string

Contains the compiled string with all groups prefixes to be prepended to every key in this cache engine
$_serializers protected

array

List of available serializer engines

Method Summary

_configDelete() protected

Deletes a single config key.
_configRead() protected

Reads a config key.
_configWrite() protected

Writes a config key.
_key() protected

Generates a safe key, taking account of the configured key prefix
_parseServerString() protected deprecated

Backwards compatible alias of parseServerString
_setOptions() protected

Settings the memcached instance
add() public

Add a key to the cache if it does not already exist.
clear() public

Delete all keys from the cache
clearGroup() public

Increments the group value to simulate deletion of all keys under a group old values will remain in storage until they expire.
config() public deprecated

Gets/Sets the config.
configShallow() public

Merge provided config with existing config. Unlike config() which does a recursive merge for nested keys, this method does a simple merge.
decrement() public

Decrements the value of an integer cached key
delete() public

Delete a key from the cache
deleteMany() public

Delete many keys from the cache at once
gc() public

Garbage collection
getConfig() public

Returns the config.
getConfigOrFail() public

Returns the config for this specific key.
getOption() public

Read an option value from the memcached connection.
groups() public

Returns the group value for each of the configured groups If the group initial value was not found, then it initializes the group accordingly.
increment() public

Increments the value of an integer cached key
init() public

Initialize the Cache Engine
key() public

Generates a safe key for use with cache engine storage engines.
parseServerString() public

Parses the server address into the host/port. Handles both IPv6 and IPv4 addresses and Unix sockets
read() public

Read a key from the cache
readMany() public

Read many keys from the cache at once
setConfig() public

Sets the config.
warning() protected

Cache Engines may trigger warnings if they encounter failures during operation, if option warnOnWriteFailures is set to true.
write() public

Write data for key into cache. When using memcached as your cache engine remember that the Memcached pecl extension does not support cache expiry times greater than 30 days in the future. Any duration greater than 30 days will be treated as real Unix time value rather than an offset from current time.
writeMany() public

Write many cache entries to the cache at once

Method Detail

_configDelete() ¶ protected

_configDelete(string $key): void

Deletes a single config key.

Parameters

string $key: Key to delete.

Returns

void

Throws

Cake\Core\Exception\Exception
if attempting to clobber existing config

_configRead() ¶ protected

_configRead(string|null $key): mixed

Reads a config key.

Parameters

string|null $key: Key to read.

Returns

mixed

_configWrite() ¶ protected

_configWrite(string|array $key, mixed $value, bool|string $merge = false): void

Writes a config key.

Parameters

string|array $key: Key to write to.
mixed $value: Value to write.
bool|string $merge optional: True to merge recursively, 'shallow' for simple merge, false to overwrite, defaults to false.

Returns

void

Throws

Cake\Core\Exception\Exception
if attempting to clobber existing config

_key() ¶ protected

_key(string $key): string

Generates a safe key, taking account of the configured key prefix

Parameters

string $key: the key passed over

Returns

string

Throws

InvalidArgumentException
If key's value is empty

_parseServerString() ¶ protected

_parseServerString(string $server): array

Backwards compatible alias of parseServerString

Parameters

string $server: The server address string.

Returns

array

_setOptions() ¶ protected

_setOptions(): void

Settings the memcached instance

Returns

void

Throws

InvalidArgumentException
When the Memcached extension is not built with the desired serializer engine.

add() ¶ public

add(string $key, mixed $value): bool

Add a key to the cache if it does not already exist.

Defaults to a non-atomic implementation. Subclasses should prefer atomic implementations.

Parameters

string $key: Identifier for the data.
mixed $value: Data to be cached.

Returns

bool

clear() ¶ public

clear(bool $check): bool

Delete all keys from the cache

Parameters

bool $check: If true will check expiration, otherwise delete all.

Returns

bool

clearGroup() ¶ public

clearGroup(string $group): bool

Increments the group value to simulate deletion of all keys under a group old values will remain in storage until they expire.

Parameters

string $group: name of the group to be cleared

Returns

bool

config() ¶ public

config(string|array|null $key = null, mixed|null $value = null, bool $merge = true): mixed

Gets/Sets the config.

Usage

Reading the whole config:

$this->config();

Reading a specific value:

$this->config('key');

Reading a nested value:

$this->config('some.nested.key');

Setting a specific value:

$this->config('key', $value);

Setting a nested value:

$this->config('some.nested.key', $value);

Updating multiple config settings at the same time:

$this->config(['one' => 'value', 'another' => 'value']);

Parameters

string|array|null $key optional: The key to get/set, or a complete array of configs.
mixed|null $value optional: The value to set.
bool $merge optional: Whether to recursively merge or overwrite existing config, defaults to true.

Returns

mixed

Throws

Cake\Core\Exception\Exception
When trying to set a key that is invalid.

configShallow() ¶ public

configShallow(string|array $key, mixed|null $value = null): $this

Merge provided config with existing config. Unlike config() which does a recursive merge for nested keys, this method does a simple merge.

Setting a specific value:

$this->configShallow('key', $value);

Setting a nested value:

$this->configShallow('some.nested.key', $value);

Updating multiple config settings at the same time:

$this->configShallow(['one' => 'value', 'another' => 'value']);

Parameters

string|array $key: The key to set, or a complete array of configs.
mixed|null $value optional: The value to set.

Returns

$this

decrement() ¶ public

decrement(string $key, int $offset = 1): int|false

Decrements the value of an integer cached key

Parameters

string $key: Identifier for the data
int $offset optional: How much to subtract

Returns

int|false

delete() ¶ public

delete(string $key): bool

Delete a key from the cache

Parameters

string $key: Identifier for the data

Returns

bool

deleteMany() ¶ public

deleteMany(array $keys): array

Delete many keys from the cache at once

Parameters

array $keys: An array of identifiers for the data

Returns

array

gc() ¶ public

gc(int|null $expires = null): void

Garbage collection

Permanently remove all expired and deleted data

Parameters

int|null $expires optional: [optional] An expires timestamp, invalidating all data before.

Returns

void

getConfig() ¶ public

getConfig(string|null $key = null, mixed|null $default = null): mixed|null

Returns the config.

Usage

Reading the whole config:

$this->getConfig();

Reading a specific value:

$this->getConfig('key');

Reading a nested value:

$this->getConfig('some.nested.key');

Reading with default value:

$this->getConfig('some-key', 'default-value');

Parameters

string|null $key optional: The key to get or null for the whole config.
mixed|null $default optional: The return value when the key does not exist.

Returns

mixed|null

getConfigOrFail() ¶ public

getConfigOrFail(string|null $key): mixed

Returns the config for this specific key.

The config value for this key must exist, it can never be null.

Parameters

string|null $key: The key to get.

Returns

mixed

Throws

InvalidArgumentException

getOption() ¶ public

getOption(string $name): string|int|bool|null

Read an option value from the memcached connection.

Parameters

string $name: The option name to read.

Returns

string|int|bool|null

groups() ¶ public

groups(): string[]

Returns the group value for each of the configured groups If the group initial value was not found, then it initializes the group accordingly.

Returns

string[]

increment() ¶ public

increment(string $key, int $offset = 1): int|false

Increments the value of an integer cached key

Parameters

string $key: Identifier for the data
int $offset optional: How much to increment

Returns

int|false

init() ¶ public

init(array $config = []): bool

Initialize the Cache Engine

Called automatically by the cache frontend

Parameters

array $config optional: array of setting for the engine

Returns

bool

Throws

InvalidArgumentException
When you try use authentication without Memcached compiled with SASL support

key() ¶ public

key(string $key): string|false

Generates a safe key for use with cache engine storage engines.

Parameters

string $key: the key passed over

Returns

string|false

parseServerString() ¶ public

parseServerString(string $server): array

Parses the server address into the host/port. Handles both IPv6 and IPv4 addresses and Unix sockets

Parameters

string $server: The server address string.

Returns

array

read() ¶ public

read(string $key): mixed

Read a key from the cache

Parameters

string $key: Identifier for the data

Returns

mixed

readMany() ¶ public

readMany(array $keys): array

Read many keys from the cache at once

Parameters

array $keys: An array of identifiers for the data

Returns

array

setConfig() ¶ public

setConfig(string|array $key, mixed|null $value = null, bool $merge = true): $this

Sets the config.

Usage

Setting a specific value:

$this->setConfig('key', $value);

Setting a nested value:

$this->setConfig('some.nested.key', $value);

Updating multiple config settings at the same time:

$this->setConfig(['one' => 'value', 'another' => 'value']);

Parameters

string|array $key: The key to set, or a complete array of configs.
mixed|null $value optional: The value to set.
bool $merge optional: Whether to recursively merge or overwrite existing config, defaults to true.

Returns

$this

Throws

Cake\Core\Exception\Exception
When trying to set a key that is invalid.

warning() ¶ protected

warning(string $message): void

Cache Engines may trigger warnings if they encounter failures during operation, if option warnOnWriteFailures is set to true.

Parameters

string $message: The warning message.

Returns

void

write() ¶ public

write(string $key, mixed $value): bool

Write data for key into cache. When using memcached as your cache engine remember that the Memcached pecl extension does not support cache expiry times greater than 30 days in the future. Any duration greater than 30 days will be treated as real Unix time value rather than an offset from current time.

Parameters

string $key: Identifier for the data
mixed $value: Data to be cached

Returns

bool

writeMany() ¶ public

writeMany(array $data): array

Write many cache entries to the cache at once

Parameters

array $data: An array of data to be stored in the cache

Returns

array

Property Detail

`$_Memcached` ¶ protected

memcached wrapper.

Type

Memcached

`$_compiledGroupNames` ¶ protected

Type

string[]

`$_config` ¶ protected

Runtime config

Type

array

`$_configInitialized` ¶ protected

Whether the config property has already been configured with defaults

Type

bool

`$_defaultConfig` ¶ protected

The default config used unless overridden by runtime configuration

compress Whether to compress data
duration Specify how long items in this cache configuration last.
groups List of groups or 'tags' associated to every key stored in this config. handy for deleting a complete group from cache.
username Login to access the Memcache server
password Password to access the Memcache server
persistent The name of the persistent connection. All configurations using the same persistent value will share a single underlying connection.
prefix Prepended to all entries. Good for when you need to share a keyspace with either another cache config or another application.
probability Probability of hitting a cache gc cleanup. Setting to 0 will disable cache::gc from ever being called automatically.
serialize The serializer engine used to serialize data. Available engines are php, igbinary and json. Beside php, the memcached extension must be compiled with the appropriate serializer support.
servers String or array of memcached servers. If an array MemcacheEngine will use them as a pool.
options - Additional options for the memcached client. Should be an array of option => value. Use the \Memcached::OPT_* constants as keys.

Type

array

`$_groupPrefix` ¶ protected

Contains the compiled string with all groups prefixes to be prepended to every key in this cache engine

Type

string

`$_serializers` ¶ protected

List of available serializer engines

Memcached must be compiled with json and igbinary support to use these engines

Type

array

Namespaces

Class MemcachedEngine

Property Summary

Method Summary

_configDelete() protected

_configRead() protected

_configWrite() protected

_key() protected

_parseServerString() protected deprecated

_setOptions() protected

add() public

clear() public

clearGroup() public

config() public deprecated

configShallow() public

decrement() public

delete() public

deleteMany() public

gc() public

getConfig() public

getConfigOrFail() public

getOption() public

groups() public

increment() public

init() public

key() public

parseServerString() public

read() public

readMany() public

setConfig() public

warning() protected

write() public

writeMany() public

Method Detail

_configDelete() ¶ protected

Parameters

Returns

Throws

_configRead() ¶ protected

Parameters

Returns

_configWrite() ¶ protected

Parameters

Returns

Throws

_key() ¶ protected

Parameters

Returns

Throws

_parseServerString() ¶ protected

Parameters

Returns

_setOptions() ¶ protected

Returns

Throws

add() ¶ public

Parameters

Returns

clear() ¶ public

Parameters

Returns

clearGroup() ¶ public

Parameters

Returns

config() ¶ public

Usage

Parameters

Returns

Throws

configShallow() ¶ public

Parameters

Returns

decrement() ¶ public

Parameters

Returns

delete() ¶ public

Parameters

Returns

deleteMany() ¶ public

Parameters

`$_Memcached` ¶ protected

`$_compiledGroupNames` ¶ protected

`$_config` ¶ protected

`$_configInitialized` ¶ protected

`$_defaultConfig` ¶ protected

`$_groupPrefix` ¶ protected

`$_serializers` ¶ protected