FileCache

API reference › yii › caching › FileCache

class	yii\caching\FileCache
Extends	Cache » yii\base\Component » yii\base\BaseObject
Implements	CacheInterface, yii\base\Configurable
Since	2.0
Source	framework/caching/FileCache.php

FileCache implements a cache component using files.

For each data value being cached, FileCache will store it in a separate file. The cache files are placed under $cachePath. FileCache will perform garbage collection automatically to remove expired cache files.

Please refer to Cache for common cache operations that are supported by FileCache.

For more details and usage information on Cache, see the guide article on caching.

Properties

Property	Type	Description	Defined by
$behaviors read-only	array<yii\base\Behavior<static>>	List of behaviors attached to this component.	yii\base\Component
$cacheFileSuffix	string	Cache file suffix. Default: '.bin'.	FileCache
$cachePath	string	The directory to store cache files. Default: '@runtime/cache'.	FileCache
$defaultDuration	int	Default duration in seconds before a cache entry will expire. Default: 0. Available since 2.0.11.	Cache
$directoryLevel	int	The level of sub-directories to store cache files. Default: 1.	FileCache
$dirMode	int	The permission to be set for newly created directories. Default: 0775.	FileCache
$fileMode	int|null	The permission to be set for newly created cache files. Default: null.	FileCache
$gcProbability	int	The probability (parts per million) that garbage collection (GC) should be performed when storing a piece of data in the cache. Default: 10.	FileCache
$keyPrefix	string	A string prefixed to every cache key. Default: ''.	FileCache
$serializer	array|null|false	The functions used to serialize and unserialize cached data. Default: null.	Cache

Methods

Method	Description	Defined by
__construct()	Constructor.	yii\base\BaseObject
__call()	Calls the named method which is not a class method.	yii\base\Component
__clone()	This method is called after the object is created by cloning an existing one.	yii\base\Component
__get()	Returns the value of a component property.	yii\base\Component
__isset()	Checks if a property is set, i.e. defined and not null.	yii\base\Component
__set()	Sets the value of a component property.	yii\base\Component
__unset()	Sets a component property to be null.	yii\base\Component
add()	Stores a value identified by a key into cache if the cache does not contain this key.	Cache
attachBehavior()	Attaches a behavior to this component.	yii\base\Component
attachBehaviors()	Attaches a list of behaviors to the component.	yii\base\Component
behaviors()	Returns a list of behaviors that this component should behave as.	yii\base\Component
buildKey()	Builds a normalized cache key from a given key.	Cache
canGetProperty()	Returns a value indicating whether a property can be read.	yii\base\Component
canSetProperty()	Returns a value indicating whether a property can be set.	yii\base\Component
className() static	Returns the fully qualified name of this class.	yii\base\BaseObject
delete()	Deletes a value with the specified key from cache.	Cache
detachBehavior()	Detaches a behavior from the component.	yii\base\Component
detachBehaviors()	Detaches all behaviors from the component.	yii\base\Component
ensureBehaviors()	Makes sure that the behaviors declared in behaviors() are attached to this component.	yii\base\Component
exists()	Checks whether a specified key exists in the cache.	FileCache
flush()	Deletes all values from cache.	Cache
gc()	Removes expired cache files.	FileCache
get()	Retrieves a value from cache with a specified key.	Cache
getBehavior()	Returns the named behavior object.	yii\base\Component
getBehaviors()	Returns all behaviors attached to this component.	yii\base\Component
getOrSet()	Method combines both set() and get() methods to retrieve value identified by a $key, or to store the result of $callable execution if there is no cache available for the $key.	Cache
hasEventHandlers()	Returns a value indicating whether there is any handler attached to the named event.	yii\base\Component
hasMethod()	Returns a value indicating whether a method is defined.	yii\base\Component
hasProperty()	Returns a value indicating whether a property is defined for this component.	yii\base\Component
init()	Initializes this component by ensuring the existence of the cache path.	FileCache
multiAdd()	Stores multiple items in cache. Each item contains a value identified by a key.	Cache
multiGet()	Retrieves multiple values from cache with the specified keys.	Cache
multiSet()	Stores multiple items in cache. Each item contains a value identified by a key.	Cache
off()	Detaches an existing event handler from this component.	yii\base\Component
offsetExists()	Returns whether there is a cache entry with a specified key.	Cache
offsetGet()	Retrieves the value from cache with a specified key.	Cache
offsetSet()	Stores the value identified by a key into cache.	Cache
offsetUnset()	Deletes the value with the specified key from cache This method is required by the interface ArrayAccess.	Cache
on()	Attaches an event handler to an event.	yii\base\Component
set()	Stores a value identified by a key into cache.	Cache
trigger()	Triggers an event.	yii\base\Component
addValue() protected	Stores a value identified by a key into cache if the cache does not contain this key.	FileCache
addValues() protected	Adds multiple key-value pairs to cache.	Cache
deleteValue() protected	Deletes a value with the specified key from cache This is the implementation of the method declared in the parent class.	FileCache
flushValues() protected	Deletes all values from cache.	FileCache
gcRecursive() protected	Recursively removing expired cache files under a directory.	FileCache
getCacheFile() protected	Returns the cache file path given the normalized cache key.	FileCache
getValue() protected	Retrieves a value from cache with a specified key.	FileCache
getValues() protected	Retrieves multiple values from cache with the specified keys.	Cache
setValue() protected	Stores a value identified by a key in cache.	FileCache
setValues() protected	Stores multiple key-value pairs in cache.	Cache

Property details

$cacheFileSuffix

public string $cacheFileSuffix = '.bin'

Cache file suffix.

Defaults to ‘.bin’.

$cachePath

public string $cachePath = '@runtime/cache'

The directory to store cache files.

You may use path alias here. If not set, it will use the “cache” subdirectory under the application runtime path.

$directoryLevel

public int $directoryLevel = 1

The level of sub-directories to store cache files.

Defaults to 1. If the system has huge number of cache files (e.g. one million), you may use a bigger value (usually no bigger than 3). Using sub-directories is mainly to ensure the file system is not over burdened with a single directory having too many files.

$dirMode

public int $dirMode = 0775

The permission to be set for newly created directories.

This value will be used by PHP chmod() function. No umask will be applied. Defaults to 0775, meaning the directory is read-writable by owner and group, but read-only for other users.

$fileMode

public int|null $fileMode = null

The permission to be set for newly created cache files.

This value will be used by PHP chmod() function. No umask will be applied. If not set, the permission will be determined by the current environment.

$gcProbability

public int $gcProbability = 10

The probability (parts per million) that garbage collection (GC) should be performed when storing a piece of data in the cache.

Defaults to 10, meaning 0.001% chance. This number should be between 0 and 1000000. A value 0 means no GC will be performed at all.

$keyPrefix

public string $keyPrefix = ''

A string prefixed to every cache key.

This is needed when you store cache data under the same $cachePath for different applications to avoid conflict.

To ensure interoperability, only alphanumeric characters should be used.

Method details

exists()

public function exists(mixed $key): bool

Checks whether a specified key exists in the cache.

This can be faster than getting the value from the cache if the data is big. Note that this method does not check whether the dependency associated with the cached data, if there is any, has changed. So a call to get() may return false while exists returns true.

Parameters

Parameter	Type	Description
$key	mixed	A key identifying the cached value. This can be a simple string or a complex data structure consisting of factors representing the key.

Returns

bool: True if a value exists in cache, false if the value is not in the cache or expired.

gc()

public function gc(bool $force = false, bool $expiredOnly = true): mixed

Removes expired cache files.

Parameters

Parameter	Type	Description
$force	bool	Whether to enforce the garbage collection regardless of $gcProbability. Defaults to false, meaning the actual deletion happens with the probability as specified by $gcProbability.
$expiredOnly	bool	Whether to removed expired cache files only. If false, all cache files under $cachePath will be removed.

Returns

mixed

init()

public function init(): mixed

Initializes this component by ensuring the existence of the cache path.

Returns

mixed

addValue()

protected function addValue(string $key, string $value, int $duration): bool

Stores a value identified by a key into cache if the cache does not contain this key.

This is the implementation of the method declared in the parent class.

Parameters

Parameter	Type	Description
$key	string	The key identifying the value to be cached
$value	string	The value to be cached. Other types (if you have disabled $serializer) unable to get is correct in getValue().
$duration	int	The number of seconds in which the cached value will expire. 0 means never expire.

Returns

bool: True if the value is successfully stored into cache, false otherwise

deleteValue()

protected function deleteValue(string $key): bool

Deletes a value with the specified key from cache This is the implementation of the method declared in the parent class.

Parameters

Parameter	Type	Description
$key	string	The key of the value to be deleted

Returns

bool: If no error happens during deletion

flushValues()

protected function flushValues(): bool

Deletes all values from cache.

This is the implementation of the method declared in the parent class.

Returns

bool: Whether the flush operation was successful.

gcRecursive()

protected function gcRecursive(string $path, bool $expiredOnly): mixed

Recursively removing expired cache files under a directory.

This method is mainly used by gc().

Parameters

Parameter	Type	Description
$path	string	The directory under which expired cache files are removed.
$expiredOnly	bool	Whether to only remove expired cache files. If false, all files under $path will be removed.

Returns

mixed

getCacheFile()

protected function getCacheFile(string $normalizedKey): string

Returns the cache file path given the normalized cache key.

Parameters

Parameter	Type	Description
$normalizedKey	string	Normalized cache key by buildKey() method

Returns

string: The cache file path

getValue()

protected function getValue(string $key): string|false

Retrieves a value from cache with a specified key.

This is the implementation of the method declared in the parent class.

Parameters

Parameter	Type	Description
$key	string	A unique key identifying the cached value

Returns

string|false: The value stored in cache, false if the value is not in the cache or expired.

setValue()

protected function setValue(string $key, string $value, int $duration): bool

Stores a value identified by a key in cache.

This is the implementation of the method declared in the parent class.

Parameters

Parameter	Type	Description
$key	string	The key identifying the value to be cached
$value	string	The value to be cached. Other types (If you have disabled $serializer) unable to get is correct in getValue().
$duration	int	The number of seconds in which the cached value will expire. Fewer than or equal to 0 means 1 year expiration time.

Returns

bool: True if the value is successfully stored into cache, false otherwise