Class NullEngine

Null cache engine, all operations return false.

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

Cake\Cache\CacheEngine uses Cake\Core\InstanceConfigTrait
Extended by Cake\Cache\Engine\NullEngine

Method Detail

clearsource public

clear( boolean $check )

Delete all keys from the cache

Parameters

boolean $check
if true will check expiration, otherwise delete all

Returns

boolean
True if the cache was successfully cleared, false otherwise

clearGroupsource public

clearGroup( string $group )

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.

Parameters

string $group
name of the group to be cleared

Returns

boolean
bool

Overrides

Cake\Cache\CacheEngine::clearGroup()

decrementsource public

decrement( string $key , integer $offset 1 )

Decrement a number under the key and return decremented value

Parameters

string $key
Identifier for the data
integer $offset optional 1
How much to subtract

Returns

boolean|integer
New incremented value, false otherwise

deletesource public

delete( string $key )

Delete a key from the cache

Parameters

string $key
Identifier for the data

Returns

boolean
True if the value was successfully deleted, false if it didn't exist or couldn't be removed

deleteManysource public

deleteMany( array $keys )

Deletes keys from the cache

Parameters

array $keys
An array of identifiers for the data

Returns

array
For each provided cache key (given back as the array key) true if the value was successfully deleted, false if it didn't exist or couldn't be removed

Overrides

Cake\Cache\CacheEngine::deleteMany()

gcsource public

gc( integer|null $expires null )

Garbage collection

Parameters

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

Overrides

Cake\Cache\CacheEngine::gc()

incrementsource public

increment( string $key , integer $offset 1 )

Increment a number under the key and return incremented value

Parameters

string $key
Identifier for the data
integer $offset optional 1
How much to add

Returns

boolean|integer
New incremented value, false otherwise

initsource public

init( array $config [] )

Initialize the cache engine

Parameters

array $config optional []
Associative array of parameters for the engine

Returns

boolean
True if the engine has been successfully initialized, false if not

Overrides

Cake\Cache\CacheEngine::init()

readsource public

read( string $key )

Read a key from the cache

Parameters

string $key
Identifier for the data

Returns

mixed
The cached data, or false if the data doesn't exist, has expired, or if there was an error fetching it

readManysource public

readMany( array $keys )

Read multiple keys from the cache

Parameters

array $keys
An array of identifiers for the data

Returns

array
For each cache key (given as the array key) the cache data associated or false if the data doesn't exist, has expired, or if there was an error fetching it

Overrides

Cake\Cache\CacheEngine::readMany()

writesource public

write( string $key , mixed $value )

Write value for a key into cache

Parameters

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

Returns

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

writeManysource public

writeMany( array $data )

Write data for many keys into cache

Parameters

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

Returns

array
of bools for each key provided, true if the data was successfully cached, false on failure

Overrides

Cake\Cache\CacheEngine::writeMany()

Methods inherited from Cake\Cache\CacheEngine

_keysource protected

_key( string $key )

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

Parameters

string $key
the key passed over

Returns

mixed
string $key or false

Throws

InvalidArgumentException
If key's value is empty

addsource public

add( string $key , mixed $value )

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

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

groupssource public

groups( )

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
array

keysource public

key( string $key )

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

Parameters

string $key
the key passed over

Returns

boolean|string
string key or false

Methods used from Cake\Core\InstanceConfigTrait

_configDeletesource protected

_configDelete( string $key )

Delete a single config key

Parameters

string $key
Key to delete.

Throws

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

_configReadsource protected

_configRead( string|null $key )

Read a config variable

Parameters

string|null $key
Key to read.

Returns

mixed
mixed

_configWritesource protected

_configWrite( string|array $key , mixed $value , boolean|string $merge false )

Write a config variable

Parameters

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

Throws

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

configsource public

config( string|array|null $key null , mixed|null $value null , boolean $merge true )

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

Returns

mixed
Config value being read, or the object itself on write operations.

Throws

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

configShallowsource public

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

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

Returns

mixed
$this The object itself.

Properties inherited from Cake\Cache\CacheEngine

$_defaultConfigsource

protected array

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.
  • probability Probability of hitting a cache gc cleanup. Setting to 0 will disable cache::gc from ever being called automatically.
[
    'duration' => 3600,
    'groups' => [],
    'prefix' => 'cake_',
    'probability' => 100
]

$_groupPrefixsource

protected string

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

null

Properties used from Cake\Core\InstanceConfigTrait

$_configsource

protected array

Runtime config

[]

$_configInitializedsource

protected boolean

Whether the config property has already been configured with defaults

false

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http://api.cakephp.org/3.1/class-Cake.Cache.Engine.NullEngine.html