Class FileEngine
File Storage engine for cache. Filestorage is the slowest cache storage to read and write. However, it is good for servers that don't have other storage engine available, or have content which is not performance sensitive.
You can configure a FileEngine cache, using Cache::config()
Property Summary
-
$_File protected
SplFileObject|nullInstance of SplFileObject class
-
$_config protected
array<string, mixed>Runtime config
-
$_configInitialized protected
boolWhether the config property has already been configured with defaults
-
$_defaultConfig protected
array<string, mixed>The default config used unless overridden by runtime configuration
-
$_groupPrefix protected
stringContains the compiled string with all group prefixes to be prepended to every key in this cache engine
-
$_init protected
boolTrue unless FileEngine::__active(); fails
Method Summary
-
_active() protected
Determine if cache directory is writable
-
_clearDirectory() protected
Used to clear a directory of matching files.
-
_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.
-
_setKey() protected
Sets the current cache key this class is managing, and creates a writable SplFileObject for the cache file the key is referring to.
-
add() public
Add a key to the cache if it does not already exist.
-
clear() public
Delete all values from the cache
-
clearGroup() public
Recursively deletes all files under any directory named as $group
-
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
Not implemented
-
delete() public
Delete a key from the cache
-
deleteMultiple() public
Deletes multiple cache items as a list
-
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
Read a key from the cache
-
getConfig() public
Returns the config.
-
getConfigOrFail() public
Returns the config for this specific key.
-
getMultiple() public
Obtains multiple cache items by their unique keys.
-
groups() public
Does whatever initialization for each group is required and returns the
group valuefor 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
Not implemented
-
init() public
Initialize File Cache Engine
-
set() public
Write data for key into cache
-
setConfig() public
Sets the config.
-
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
_clearDirectory() ¶ protected
_clearDirectory(string $path): voidUsed to clear a directory of matching files.
Parameters
-
string$path The path to search.
Returns
void_configDelete() ¶ protected
_configDelete(string $key): voidDeletes a single config key.
Parameters
-
string$key Key to delete.
Returns
voidThrows
Cake\Core\Exception\CakeExceptionif attempting to clobber existing config
_configRead() ¶ protected
_configRead(string|null $key): mixedReads a config key.
Parameters
-
string|null$key Key to read.
Returns
mixed_configWrite() ¶ protected
_configWrite(array<string, mixed>|string $key, mixed $value, string|bool $merge = false): voidWrites a config key.
Parameters
-
array<string, mixed>|string$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
voidThrows
Cake\Core\Exception\CakeExceptionif attempting to clobber existing config
_key() ¶ protected
_key(string $key): stringGenerates a key for cache backend usage.
If the requested key is valid, the group prefix value and engine prefix are applied. Whitespace in keys will be replaced.
Parameters
-
string$key
Returns
string_setKey() ¶ protected
_setKey(string $key, bool $createKey = false): boolSets the current cache key this class is managing, and creates a writable SplFileObject for the cache file the key is referring to.
Parameters
-
string$key The key
-
bool$createKey optional Whether the key should be created if it doesn't exists, or not
Returns
booltrue if the cache key could be set, false otherwise
add() ¶ public
add(string $key, mixed $value): boolAdd a key to the cache if it does not already exist.
Defaults to a non-atomic implementation. Subclasses should prefer atomic implementations.
Parameters
-
string$key Identifier for the data.
-
mixed$value Data to be cached.
Returns
boolTrue if the data was successfully cached, false on failure.
clear() ¶ public
clear(): boolDelete all values from the cache
Returns
boolTrue if the cache was successfully cleared, false otherwise
clearGroup() ¶ public
clearGroup(string $group): boolRecursively deletes all files under any directory named as $group
Each implementation needs to decide whether actually delete the keys or just augment a group generation value to achieve the same result.
Parameters
-
string$group The group to clear.
Returns
boolsuccess
configShallow() ¶ public
configShallow(array<string, mixed>|string $key, mixed|null $value = null): $thisMerge 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
$thisdecrement() ¶ public
decrement(string $key, int $offset = 1): int|falseNot implemented
Parameters
-
string$key The key to decrement
-
int$offset optional The number to offset
Returns
int|falseThrows
LogicExceptiondelete() ¶ public
delete(string $key): boolDelete a key from the cache
Parameters
-
string$key Identifier for the data
Returns
boolTrue if the value was successfully deleted, false if it didn't exist or couldn't be removed
deleteMultiple() ¶ public
deleteMultiple(iterable $keys): boolDeletes multiple cache items as a list
This is a best effort attempt. If deleting an item would create an error it will be ignored, and all items will be attempted.
Parameters
-
iterable$keys A list of string-based keys to be deleted.
Returns
boolTrue if the items were successfully removed. False if there was an error.
Throws
Cake\Cache\Exception\InvalidArgumentExceptionIf $keys is neither an array nor a Traversable, or if any of the $keys are not a legal value.
duration() ¶ protected
duration(DateInterval|int|null $ttl): intConvert the various expressions of a TTL value into duration in seconds
Parameters
-
DateInterval|int|null$ttl The TTL value of this item. If null is sent, the driver's default duration will be used.
Returns
intensureValidKey() ¶ protected
ensureValidKey(string $key): voidEnsure the validity of the given cache key.
Parameters
-
string$key Key to check.
Returns
voidThrows
Cake\Cache\Exception\InvalidArgumentExceptionWhen the key is not valid.
ensureValidType() ¶ protected
ensureValidType(iterable $iterable, string $check = self::CHECK_VALUE): voidEnsure the validity of the argument type and cache keys.
Parameters
-
iterable$iterable The iterable to check.
-
string$check optional Whether to check keys or values.
Returns
voidThrows
Cake\Cache\Exception\InvalidArgumentExceptionget() ¶ public
get(string $key, mixed $default = null): mixedRead a key from the cache
Parameters
-
string$key Identifier for the data
-
mixed$default optional Default value to return if the key does not exist.
Returns
mixedThe cached data, or default value if the data doesn't exist, has expired, or if there was an error fetching it
getConfig() ¶ public
getConfig(string|null $key = null, mixed $default = null): mixedReturns 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
mixedConfiguration data at the named key or null if the key does not exist.
getConfigOrFail() ¶ public
getConfigOrFail(string $key): mixedReturns the config for this specific key.
The config value for this key must exist, it can never be null.
Parameters
-
string$key The key to get.
Returns
mixedConfiguration data at the named key
Throws
InvalidArgumentExceptiongetMultiple() ¶ public
getMultiple(iterable $keys, mixed $default = null): iterableObtains multiple cache items by their unique keys.
Parameters
-
iterable$keys A list of keys that can obtained in a single operation.
-
mixed$default optional Default value to return for keys that do not exist.
Returns
iterableA list of key value pairs. Cache keys that do not exist or are stale will have $default as value.
Throws
Cake\Cache\Exception\InvalidArgumentExceptionIf $keys is neither an array nor a Traversable, or if any of the $keys are not a legal value.
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 $key): boolDetermines whether an item is present in the cache.
NOTE: It is recommended that has() is only to be used for cache warming type purposes and not to be used within your live applications operations for get/set, as this method is subject to a race condition where your has() will return true and immediately after, another script can remove it making the state of your app out of date.
Parameters
-
string$key The cache item key.
Returns
boolThrows
Cake\Cache\Exception\InvalidArgumentExceptionIf the $key string is not a legal value.
increment() ¶ public
increment(string $key, int $offset = 1): int|falseNot implemented
Parameters
-
string$key The key to increment
-
int$offset optional The number to offset
Returns
int|falseThrows
LogicExceptioninit() ¶ public
init(array<string, mixed> $config = []): boolInitialize File Cache Engine
Called automatically by the cache frontend.
Parameters
-
array<string, mixed>$config optional array of setting for the engine
Returns
boolTrue if the engine has been successfully initialized, false if not
set() ¶ public
set(string $key, mixed $value, DateInterval|int|null $ttl = null): boolWrite data for key into cache
Parameters
-
string$key Identifier for the data
-
mixed$value Data to be cached
-
DateInterval|int|null$ttl optional Optional. The TTL value of this item. If no value is sent and the driver supports TTL then the library may set a default value for it or let the driver take care of that.
Returns
boolTrue on success and false on failure.
setConfig() ¶ public
setConfig(array<string, mixed>|string $key, mixed|null $value = null, bool $merge = true): $thisSets 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
$thisThrows
Cake\Core\Exception\CakeExceptionWhen trying to set a key that is invalid.
setMultiple() ¶ public
setMultiple(iterable $values, DateInterval|int|null $ttl = null): boolPersists a set of key => value pairs in the cache, with an optional TTL.
Parameters
-
iterable$values A list of key => value pairs for a multiple-set operation.
-
DateInterval|int|null$ttl optional Optional. The TTL value of this item. If no value is sent and the driver supports TTL then the library may set a default value for it or let the driver take care of that.
Returns
boolTrue on success and false on failure.
Throws
Cake\Cache\Exception\InvalidArgumentExceptionIf $values is neither an array nor a Traversable, or if any of the $values are not a legal value.
warning() ¶ protected
warning(string $message): voidCache Engines may trigger warnings if they encounter failures during operation, if option warnOnWriteFailures is set to true.
Parameters
-
string$message The warning message.
Returns
voidProperty Detail
$_configInitialized ¶ protected
Whether the config property has already been configured with defaults
Type
bool$_defaultConfig ¶ protected
The default config used unless overridden by runtime configuration
durationSpecify how long items in this cache configuration last.groupsList of groups or 'tags' associated to every key stored in this config. handy for deleting a complete group from cache.lockUsed by FileCache. Should files be locked before writing to them?maskThe mask used for created filesdirMaskThe mask used for created folderspathPath to where cachefiles should be saved. Defaults to system's temp dir.prefixPrepended to all entries. Good for when you need to share a keyspace with either another cache config or another application. cache::gc from ever being called automatically.serializeShould cache objects be serialized first.
Type
array<string, mixed>$_groupPrefix ¶ protected
Contains the compiled string with all group prefixes to be prepended to every key in this cache engine
Type
string