TYPO3 13.4 API: FileBackend

FileBackend extends SimpleFileBackend implements FreezableBackendInterface, TaggableBackendInterface

A caching backend which stores cache entries in files

Interfaces

FreezableBackendInterface: A contract for a cache backend which can be frozen.
TaggableBackendInterface: A contract for a cache backend which supports tagging.

Constants

DATASIZE_DIGITS = 10
DATETIME_EXPIRYTIME_UNLIMITED = '9999-12-31T23:59:59+0000'
EXPIRYTIME_FORMAT = 'YmdHis'
EXPIRYTIME_LENGTH = 14
SEPARATOR = '^'
UNLIMITED_LIFETIME = 0

Properties

$cache : FrontendInterface: Reference to the cache which uses this backend
$cacheDirectory : string: Directory where the files are stored
$cacheEntryFileExtension : string: A file extension to use for each cache entry.
$cacheEntryIdentifiers : array<string|int, mixed>
$cacheIdentifier : string
$context : string: The current application context
$defaultLifetime : int: Default lifetime of a cache entry in seconds
$frozen : bool
$temporaryCacheDirectory : string: Temporary path to cache directory before setCache() was called. It is set by setCacheDirectory() and used in setCache() method which calls the directory creation if needed. The variable is not used afterwards, the final cache directory path is stored in $this->cacheDirectory then.

Methods

__construct() : mixed: Constructs this backend
collectGarbage() : mixed: Does garbage collection
findIdentifiersByTag() : array<string|int, mixed>: Finds and returns all cache entry identifiers which are tagged by the specified tag.
flush() : mixed: Removes all cache entries of this cache and sets the frozen flag to FALSE.
flushByTag() : mixed: Removes all cache entries of this cache which are tagged by the specified tag.
flushByTags() : mixed: Backwards compatibility safeguard since re-introducing flushByTags as API.
freeze() : mixed: Freezes this cache backend.
get() : mixed: Loads data from a cache file.
getCacheDirectory() : string: Returns the directory where the cache files are stored
has() : bool: Checks if a cache entry with the specified identifier exists.
isFrozen() : bool: Tells if this backend is frozen.
remove() : bool: Removes all cache entries matching the specified identifier.
require() : mixed: Loads PHP code from the cache and require it right away.
requireOnce() : mixed: Loads PHP code from the cache and require_onces it right away.
set() : mixed: Saves data in a cache file.
setCache() : mixed: Sets a reference to the cache frontend which uses this backend and initializes the default cache directory.
setCacheDirectory() : mixed: Sets the directory where the cache files are stored. By default it is assumed that the directory is below TYPO3's Project Path. However, an absolute path can be selected, too.
setDefaultLifetime() : mixed: Sets the default lifetime for this cache backend
calculateExpiryTime() : DateTime: Calculates the expiry time by the given lifetime. If no lifetime is specified, the default lifetime is used.
createFinalCacheDirectory() : mixed: Create the final cache directory if it does not exist.
findCacheFilesByIdentifier() : mixed: Tries to find the cache entry for the specified identifier.
isCacheFileExpired() : bool: Checks if the given cache entry files are still valid or if their lifetime has exceeded.

DATASIZE_DIGITS


    public
        mixed
    DATASIZE_DIGITS
    = 10

DATETIME_EXPIRYTIME_UNLIMITED


    public
        mixed
    DATETIME_EXPIRYTIME_UNLIMITED
    = '9999-12-31T23:59:59+0000'

EXPIRYTIME_FORMAT


    public
        mixed
    EXPIRYTIME_FORMAT
    = 'YmdHis'

EXPIRYTIME_LENGTH


    public
        mixed
    EXPIRYTIME_LENGTH
    = 14

SEPARATOR


    public
        mixed
    SEPARATOR
    = '^'

UNLIMITED_LIFETIME


    public
        mixed
    UNLIMITED_LIFETIME
    = 0

$cache

Reference to the cache which uses this backend


        protected
            FrontendInterface
    $cache

$cacheDirectory

Directory where the files are stored


        protected
            string
    $cacheDirectory
     = ''

$cacheEntryFileExtension

A file extension to use for each cache entry.


        protected
            string
    $cacheEntryFileExtension
     = ''

$cacheEntryIdentifiers


        protected
            array<string|int, mixed>
    $cacheEntryIdentifiers
     = []

$cacheIdentifier


        protected
            string
    $cacheIdentifier

$context

The current application context


        protected
            string
    $context

This variable is currently unused and set to "production" always. It is only kept to keep backwards compatibility.

$defaultLifetime

Default lifetime of a cache entry in seconds


        protected
            int
    $defaultLifetime
     = 3600

$frozen


        protected
            bool
    $frozen
     = false

$temporaryCacheDirectory

Temporary path to cache directory before setCache() was called. It is set by setCacheDirectory() and used in setCache() method which calls the directory creation if needed. The variable is not used afterwards, the final cache directory path is stored in $this->cacheDirectory then.


        protected
            string
    $temporaryCacheDirectory
     = ''

Temporary path to cache directory

__construct()

Constructs this backend


    public
                    __construct(string $context[, array<string|int, mixed> $options = [] ]) : mixed

Parameters

$context : string: Unused, for backward compatibility only
$options : array<string|int, mixed> = []: Configuration options - depends on the actual backend

collectGarbage()

Does garbage collection


    public
                    collectGarbage() : mixed

findIdentifiersByTag()

Finds and returns all cache entry identifiers which are tagged by the specified tag.


    public
                    findIdentifiersByTag(string $searchedTag) : array<string|int, mixed>

Parameters

$searchedTag : string: The tag to search for

Return values

array<string|int, mixed> —

An array with identifiers of all matching entries. An empty array if no entries matched

flush()

Removes all cache entries of this cache and sets the frozen flag to FALSE.


    public
                    flush() : mixed

flushByTag()

Removes all cache entries of this cache which are tagged by the specified tag.


    public
                    flushByTag(string $tag) : mixed

Parameters

$tag : string: The tag the entries must have

flushByTags()

Backwards compatibility safeguard since re-introducing flushByTags as API.


    public
                    flushByTags(array<string|int, string> $tags) : mixed

See https://review.typo3.org/#/c/50537/ comments for patch set 14.

The method is here even though it is only required for TaggableBackendInterface. We add it here to ensure third party cache backends do not fail but instead delegate to a less efficient linear flushing behavior.

Parameters

$tags : array<string|int, string>

freeze()

Freezes this cache backend.


    public
                    freeze() : mixed

All data in a frozen backend remains unchanged and methods which try to add or modify data result in an exception thrown. Possible expiry times of individual cache entries are ignored.

On the positive side, a frozen cache backend is much faster on read access. A frozen backend can only be thawed by calling the flush() method.

get()

Loads data from a cache file.


    public
                    get(string $entryIdentifier) : mixed

Parameters

$entryIdentifier : string: An identifier which describes the cache entry to load

Return values

mixed —

The cache entry's content as a string or FALSE if the cache entry could not be loaded

getCacheDirectory()

Returns the directory where the cache files are stored


    public
                    getCacheDirectory() : string

Return values

string —

Full path of the cache directory

has()

Checks if a cache entry with the specified identifier exists.


    public
                    has(string $entryIdentifier) : bool

Parameters

$entryIdentifier : string

Return values

bool —

TRUE if such an entry exists, FALSE if not

isFrozen()

Tells if this backend is frozen.


    public
                    isFrozen() : bool

Return values

bool

remove()

Removes all cache entries matching the specified identifier.


    public
                    remove(string $entryIdentifier) : bool

Usually this only affects one entry.

Parameters

$entryIdentifier : string: Specifies the cache entry to remove

Return values

bool —

TRUE if (at least) an entry could be removed or FALSE if no entry was found

require()

Loads PHP code from the cache and require it right away.


    public
                    require(string $entryIdentifier) : mixed

Parameters

$entryIdentifier : string: An identifier which describes the cache entry to load

Return values

mixed —

Potential return value from the include operation

requireOnce()

Loads PHP code from the cache and require_onces it right away.


    public
                    requireOnce(string $entryIdentifier) : mixed

Parameters

$entryIdentifier : string: An identifier which describes the cache entry to load

Return values

mixed —

Potential return value from the include operation

set()

Saves data in a cache file.


    public
                    set(string $entryIdentifier, string $data[, array<string|int, mixed> $tags = [] ][, int $lifetime = null ]) : mixed

Parameters

$entryIdentifier : string: An identifier for this specific cache entry
$data : string: The data to be stored
$tags : array<string|int, mixed> = []: Tags to associate with this cache entry
$lifetime : int = null: Lifetime of this cache entry in seconds. If NULL is specified, the default lifetime is used. "0" means unlimited lifetime.

setCache()

Sets a reference to the cache frontend which uses this backend and initializes the default cache directory.


    public
                    setCache(FrontendInterface $cache) : mixed

This method also detects if this backend is frozen and sets the internal flag accordingly.

Parameters

$cache : FrontendInterface: The cache frontend

setCacheDirectory()

Sets the directory where the cache files are stored. By default it is assumed that the directory is below TYPO3's Project Path. However, an absolute path can be selected, too.


    public
                    setCacheDirectory(string $cacheDirectory) : mixed

This method enables to use a cache path outside of TYPO3's Project Path. The final cache path is checked and created in createFinalCacheDirectory(), called by setCache() method, which is done after the cacheDirectory option was handled.

Parameters

$cacheDirectory : string: The cache base directory. If a relative path

setDefaultLifetime()

Sets the default lifetime for this cache backend


    public
                    setDefaultLifetime(int $defaultLifetime) : mixed

Parameters

$defaultLifetime : int: Default lifetime of this cache backend in seconds. If NULL is specified, the default lifetime is used. "0" means unlimited lifetime.

calculateExpiryTime()

Calculates the expiry time by the given lifetime. If no lifetime is specified, the default lifetime is used.


    protected
                    calculateExpiryTime([int $lifetime = null ]) : DateTime

Parameters

$lifetime : int = null: The lifetime in seconds

Return values

DateTime —

The expiry time

createFinalCacheDirectory()

Create the final cache directory if it does not exist.


    protected
                    createFinalCacheDirectory(string $finalCacheDirectory) : mixed

Parameters

$finalCacheDirectory : string: Absolute path to final cache directory

findCacheFilesByIdentifier()

Tries to find the cache entry for the specified identifier.


    protected
                    findCacheFilesByIdentifier(string $entryIdentifier) : mixed

Usually only one cache entry should be found - if more than one exist, this is due to some error or crash.

Parameters

$entryIdentifier : string: The cache entry identifier

Return values

mixed —

The filenames (including path) as an array if one or more entries could be found, otherwise FALSE

isCacheFileExpired()

Checks if the given cache entry files are still valid or if their lifetime has exceeded.


    protected
                    isCacheFileExpired(string $cacheEntryPathAndFilename) : bool

Parameters

$cacheEntryPathAndFilename : string

Return values

bool

FileBackend extends SimpleFileBackend implements FreezableBackendInterface, TaggableBackendInterface

Table of Contents

Interfaces

Constants

Properties

Methods

Constants

DATASIZE_DIGITS

DATETIME_EXPIRYTIME_UNLIMITED

EXPIRYTIME_FORMAT

EXPIRYTIME_LENGTH

SEPARATOR

UNLIMITED_LIFETIME

Properties

$cache

$cacheDirectory

$cacheEntryFileExtension

$cacheEntryIdentifiers

$cacheIdentifier

$context

$defaultLifetime

$frozen

$temporaryCacheDirectory

Methods

__construct()

Parameters

Tags

collectGarbage()

findIdentifiersByTag()

Parameters

Return values

flush()

flushByTag()

Parameters

flushByTags()

Parameters

freeze()

Tags

get()

Parameters

Tags

Return values

getCacheDirectory()

Return values

has()

Parameters

Tags

Return values

isFrozen()

Return values

remove()

Parameters

Tags

Return values

require()

Parameters

Tags

Return values

requireOnce()

Parameters

Tags

Return values

set()

Parameters

Tags

setCache()

Parameters

setCacheDirectory()

Parameters

Tags

setDefaultLifetime()

Parameters

Tags

calculateExpiryTime()

Parameters

Return values

createFinalCacheDirectory()

Parameters

Tags

findCacheFilesByIdentifier()