Class NullEngine

Null cache engine, all operations appear to work, but do nothing.

This is used internally for when Cache::disable() has been called.

Namespace: Cake\Cache\Engine

Constants

string

CHECK_KEY ¶
```
'key'
```
string

CHECK_VALUE ¶
```
'value'
```

Property Summary

$_config protected

array<string, mixed>

Runtime config
$_configInitialized protected

bool

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

array<string, mixed>

The default cache configuration is overridden in most cache adapters. These are the keys that are common to all adapters. If overridden, this property is not used.
$_eventClass protected

string

Default class name for new event objects.
$_eventManager protected

Cake\Event\EventManagerInterface

Instance of the Cake\Event\EventManager this object is using to dispatch inner events.
$_groupPrefix protected

string

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

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 key for cache backend usage.
add() public

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

Delete all keys from the cache
clearGroup() public

Clears all values belonging to a group. Is up to the implementing engine to decide whether actually delete the keys or just simulate it to achieve the same result.
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

Decrement a number under the key and return decremented value
delete() public

Delete a key from the cache
deleteConfig() public

Deletes a config key.
deleteMultiple() public

Deletes multiple cache items as a list
dispatchEvent() public

Wrapper for creating and dispatching events.
duration() protected

Convert the various expressions of a TTL value into duration in seconds
ensureValidKey() protected

Ensure the validity of the given cache key.
ensureValidType() protected

Ensure the validity of the argument type and cache keys.
get() public

Fetches the value for a given key from the cache.
getConfig() public

Returns the config.
getConfigOrFail() public

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

Returns the Cake\Event\EventManager manager instance for this object.
getMultiple() public

Obtains multiple cache items by their unique keys.
groups() public

Does whatever initialization for each group is required and returns the group value for each of them, this is the token representing each group in the cache key
has() public

Determines whether an item is present in the cache.
increment() public

Increment a number under the key and return incremented value
init() public

Initialize the cache engine
set() public

Persists data in the cache, uniquely referenced by the given key with an optional expiration TTL time.
setConfig() public

Sets the config.
setEventManager() public

Returns the Cake\Event\EventManagerInterface instance for this object.
setMultiple() public

Persists a set of key => value pairs in the cache, with an optional TTL.
warning() protected

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

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\CakeException
if attempting to clobber existing config

_configRead() ¶ protected

_configRead(string|null $key): $key is null ? array : mixed

Reads a config key.

Parameters

string|null $key: Key to read.

Returns

$key is null ? array : mixed

_configWrite() ¶ protected

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

Writes a config key.

Parameters

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

Returns

void

Throws

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

_key() ¶ protected

_key(string $key): string

Generates a key for cache backend usage.

If the requested key is valid, the group prefix value and engine prefix are applied. Whitespace in keys will be replaced.

Parameters

string $key: the key passed over

Returns

string

Prefixed key with potentially unsafe characters replaced.

Throws

Cake\Cache\Exception\InvalidArgumentException
If key's value is invalid.

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

True if the data was successfully cached, false on failure.

clear() ¶ public

clear(): bool

Delete all keys from the cache

Returns

bool

clearGroup() ¶ public

clearGroup(string $group): bool

Clears all values belonging to a group. Is up to the implementing engine to decide whether actually delete the keys or just simulate it to achieve the same result.

Each implementation needs to decide whether actually delete the keys or just augment a group generation value to achieve the same result.

Parameters

string $group

Returns

bool

configShallow() ¶ public

configShallow(array<string, mixed>|string $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

array<string, mixed>|string $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

Decrement a number under the key and return decremented value

Parameters

string $key
int $offset optional

Returns

int|false

delete() ¶ public

delete(string $key): bool

Delete a key from the cache

Parameters

string $key

Returns

bool

deleteConfig() ¶ public

deleteConfig(string $key): $this

Deletes a config key.

Parameters

string $key: Key to delete. It can be a dot separated string to delete nested keys.

Returns

$this

deleteMultiple() ¶ public

deleteMultiple(iterable<string> $keys): bool

Deletes multiple cache items as a list

This is a best effort attempt. If deleting an item would create an error it will be ignored, and all items will be attempted.

Parameters

iterable<string> $keys

Returns

bool

dispatchEvent() ¶ public

dispatchEvent(string $name, array $data = [], TSubject|null $subject = null): Cake\Event\EventInterface<TSubject>

Wrapper for creating and dispatching events.

Returns a dispatched event.

Parameters

string $name: Name of the event.
array $data optional: Any value you wish to be transported with this event to it can be read by listeners.
TSubject|null $subject optional: The object that this event applies to ($this by default).

Returns

Cake\Event\EventInterface<TSubject>

duration() ¶ protected

duration(DateInterval|int|null $ttl): int

Convert the various expressions of a TTL value into duration in seconds

Parameters

DateInterval|int|null $ttl: The TTL value of this item. If null is sent, the driver's default duration will be used.

Returns

int

ensureValidKey() ¶ protected

ensureValidKey(mixed $key): void

Ensure the validity of the given cache key.

Parameters

mixed $key: Key to check.

Returns

void

Throws

Cake\Cache\Exception\InvalidArgumentException
When the key is not valid.

ensureValidType() ¶ protected

ensureValidType(iterable $iterable, string $check = self::CHECK_VALUE): void

Ensure the validity of the argument type and cache keys.

Parameters

iterable $iterable: The iterable to check.
string $check optional: Whether to check keys or values.

Returns

void

Throws

Cake\Cache\Exception\InvalidArgumentException

get() ¶ public

get(string $key, mixed $default = null): mixed

Fetches the value for a given key from the cache.

Parameters

string $key
mixed $default optional

Returns

mixed

getConfig() ¶ public

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

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 $default optional: The return value when the key does not exist.

Returns

$key is null ? array : mixed

Configuration data at the named key or null if the key does not exist.

getConfigOrFail() ¶ public

getConfigOrFail(string $key): mixed

Returns the config for this specific key.

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

Parameters

string $key: The key to get.

Returns

mixed

Configuration data at the named key

Throws

InvalidArgumentException

getEventManager() ¶ public

getEventManager(): Cake\Event\EventManagerInterface

Returns the Cake\Event\EventManager manager instance for this object.

You can use this instance to register any new listeners or callbacks to the object events, or create your own events and trigger them at will.

Returns

Cake\Event\EventManagerInterface

getMultiple() ¶ public

getMultiple(iterable<string> $keys, mixed $default = null): iterable<string, mixed>

Obtains multiple cache items by their unique keys.

Parameters

iterable<string> $keys
mixed $default optional

Returns

iterable<string, mixed>

groups() ¶ public

groups(): array<string>

Does whatever initialization for each group is required and returns the group value for each of them, this is the token representing each group in the cache key

Returns

array<string>

has() ¶ public

has(string $key): bool

Determines whether an item is present in the cache.

NOTE: It is recommended that has() is only to be used for cache warming type purposes and not to be used within your live applications operations for get/set, as this method is subject to a race condition where your has() will return true and immediately after, another script can remove it making the state of your app out of date.

Parameters

string $key: The cache item key.

Returns

bool

Throws

Cake\Cache\Exception\InvalidArgumentException
If the $key string is not a legal value.

increment() ¶ public

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

Increment a number under the key and return incremented value

Parameters

string $key
int $offset optional

Returns

int|false

init() ¶ public

init(array<string, mixed> $config = []): bool

Initialize the cache engine

Called automatically by the cache frontend. Merge the runtime config with the defaults before use.

Parameters

array<string, mixed> $config optional

Returns

bool

set() ¶ public

set(string $key, mixed $value, DateInterval|int|null $ttl = null): bool

Persists data in the cache, uniquely referenced by the given key with an optional expiration TTL time.

Parameters

string $key
mixed $value
DateInterval|int|null $ttl optional

Returns

bool

setConfig() ¶ public

setConfig(array<string, mixed>|string $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

array<string, mixed>|string $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\CakeException
When trying to set a key that is invalid.

setEventManager() ¶ public

setEventManager(Cake\Event\EventManagerInterface $eventManager): $this

Returns the Cake\Event\EventManagerInterface instance for this object.

You can use this instance to register any new listeners or callbacks to the object events, or create your own events and trigger them at will.

Parameters

Cake\Event\EventManagerInterface $eventManager: the eventManager to set

Returns

$this

setMultiple() ¶ public

setMultiple(iterable $values, DateInterval|int|null $ttl = null): bool

Persists a set of key => value pairs in the cache, with an optional TTL.

Parameters

iterable $values
DateInterval|int|null $ttl optional

Returns

bool

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

Property Detail

`$_config` ¶ protected

Runtime config

Type

array<string, mixed>

`$_configInitialized` ¶ protected

Whether the config property has already been configured with defaults

Type

bool

`$_defaultConfig` ¶ protected

The default cache configuration is overridden in most cache adapters. These are the keys that are common to all adapters. If overridden, this property is not used.

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.
prefix Prefix appended to all entries. Good for when you need to share a keyspace with either another cache config or another application.
warnOnWriteFailures Some engines, such as ApcuEngine, may raise warnings on write failures.

Type

array<string, mixed>

`$_eventClass` ¶ protected

Default class name for new event objects.

Type

string

`$_eventManager` ¶ protected

Instance of the Cake\Event\EventManager this object is using to dispatch inner events.

Type

Cake\Event\EventManagerInterface

`$_groupPrefix` ¶ protected

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

Type

string

Namespaces

Class NullEngine

Constants

Property Summary

Method Summary

_configDelete() protected

_configRead() protected

_configWrite() protected

_key() protected

add() public

clear() public

clearGroup() public

configShallow() public

decrement() public

delete() public

deleteConfig() public

deleteMultiple() public

dispatchEvent() public

duration() protected

ensureValidKey() protected

ensureValidType() protected

get() public

getConfig() public

getConfigOrFail() public

getEventManager() public

getMultiple() public

groups() public

has() public

increment() public

init() public

set() public

setConfig() public

setEventManager() public

setMultiple() public

warning() protected

Method Detail

_configDelete() ¶ protected

Parameters

Returns

Throws

_configRead() ¶ protected

Parameters

Returns

_configWrite() ¶ protected

Parameters

Returns

Throws

_key() ¶ protected

Parameters

Returns

Throws

add() ¶ public

Parameters

Returns

clear() ¶ public

Returns

clearGroup() ¶ public

Parameters

Returns

configShallow() ¶ public

Parameters

Returns

decrement() ¶ public

Parameters

Returns

delete() ¶ public

Parameters

Returns

deleteConfig() ¶ public

Parameters

Returns

deleteMultiple() ¶ public

Parameters

Returns

dispatchEvent() ¶ public

Parameters

Returns

duration() ¶ protected

Parameters

Returns

`$_config` ¶ protected

`$_configInitialized` ¶ protected

`$_defaultConfig` ¶ protected

`$_eventClass` ¶ protected

`$_eventManager` ¶ protected

`$_groupPrefix` ¶ protected