Class NullEngine
Null cache engine, all operations appear to work, but do nothing.
This is used internally for when Cache::disable() has been called.
Property Summary
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$_config protected
array<string, mixed>Runtime config
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$_configInitialized protected
boolWhether the config property has already been configured with defaults
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$_defaultConfig protected
array<string, mixed>The default cache configuration is overridden in most cache adapters. These are the keys that are common to all adapters. If overridden, this property is not used.
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$_groupPrefix protected
stringContains the compiled string with all group prefixes to be prepended to every key in this cache engine
Method Summary
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_configDelete() protected
Deletes a single config key.
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_configRead() protected
Reads a config key.
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_configWrite() protected
Writes a config key.
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_key() protected
Generates a key for cache backend usage.
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add() public
Add a key to the cache if it does not already exist.
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clear() public
Delete all keys from the cache
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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.
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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
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delete() public
Delete a key from the cache
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deleteMultiple() public
Deletes multiple cache items as a list
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duration() protected
Convert the various expressions of a TTL value into duration in seconds
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ensureValidKey() protected
Ensure the validity of the given cache key.
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ensureValidType() protected
Ensure the validity of the argument type and cache keys.
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get() public
Fetches the value for a given key from the cache.
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getConfig() public
Returns the config.
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getConfigOrFail() public
Returns the config for this specific key.
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getMultiple() public
Obtains multiple cache items by their unique keys.
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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.
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increment() public
Increment a number under the key and return incremented value
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init() public
Initialize the cache engine
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set() public
Persists data in the cache, uniquely referenced by the given key with an optional expiration TTL time.
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setConfig() public
Sets the config.
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setMultiple() public
Persists a set of key => value pairs in the cache, with an optional TTL.
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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 $key): voidDeletes a single config key.
Parameters
-
string$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 $merge = false): voidWrites a config key.
Parameters
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array<string, mixed>|string$key Key to write to.
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mixed$value Value to write.
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string|bool$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 the key passed over
Returns
stringThrows
Cake\Cache\Exception\InvalidArgumentExceptionIf key's value is invalid.
add() ¶ public
add(string $key, mixed $value): boolAdd a key to the cache if it does not already exist.
Defaults to a non-atomic implementation. Subclasses should prefer atomic implementations.
Parameters
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string$key Identifier for the data.
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mixed$value Data to be cached.
Returns
boolclearGroup() ¶ public
clearGroup(string $group): boolClears all values belonging to a group. Is up to the implementing engine to decide whether actually delete the keys or just simulate it to achieve the same result.
Each implementation needs to decide whether actually delete the keys or just augment a group generation value to achieve the same result.
Parameters
-
string$group
Returns
boolconfigShallow() ¶ 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:
$this->configShallow(['one' => 'value', 'another' => 'value']);Parameters
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array<string, mixed>|string$key The key to set, or a complete array of configs.
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mixed|null$value optional The value to set.
Returns
$thisdecrement() ¶ public
decrement(string $key, int $offset = 1): int|falseDecrement a number under the key and return decremented value
Parameters
-
string$key -
int$offset optional
Returns
int|falsedelete() ¶ public
delete(string $key): boolDelete a key from the cache
Parameters
-
string$key
Returns
booldeleteMultiple() ¶ public
deleteMultiple(iterable<string> $keys): boolDeletes multiple cache items as a list
This is a best effort attempt. If deleting an item would create an error it will be ignored, and all items will be attempted.
Parameters
-
iterable<string>$keys
Returns
boolduration() ¶ protected
duration(DateInterval|int|null $ttl): intConvert the various expressions of a TTL value into duration in seconds
Parameters
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DateInterval|int|null$ttl The TTL value of this item. If null is sent, the driver's default duration will be used.
Returns
intensureValidKey() ¶ protected
ensureValidKey(mixed $key): voidEnsure the validity of the given cache key.
Parameters
-
mixed$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.
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string$check optional Whether to check keys or values.
Returns
voidThrows
Cake\Cache\Exception\InvalidArgumentExceptionget() ¶ public
get(string $key, mixed $default = null): mixedFetches the value for a given key from the cache.
Parameters
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string$key -
mixed$default optional
Returns
mixedgetConfig() ¶ 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:
$this->getConfig('some-key', 'default-value');Parameters
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string|null$key optional The key to get or null for the whole config.
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mixed$default optional The return value when the key does not exist.
Returns
mixedgetConfigOrFail() ¶ 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
mixedThrows
InvalidArgumentExceptiongetMultiple() ¶ 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 $key): boolDetermines whether an item is present in the cache.
NOTE: It is recommended that has() is only to be used for cache warming type purposes and not to be used within your live applications operations for get/set, as this method is subject to a race condition where your has() will return true and immediately after, another script can remove it making the state of your app out of date.
Parameters
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string$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 $offset = 1): int|falseIncrement a number under the key and return incremented value
Parameters
-
string$key -
int$offset optional
Returns
int|falseinit() ¶ public
init(array<string, mixed> $config = []): boolInitialize the cache engine
Called automatically by the cache frontend. Merge the runtime config with the defaults before use.
Parameters
-
array<string, mixed>$config optional
Returns
boolset() ¶ public
set(string $key, mixed $value, DateInterval|int|null $ttl = null): boolPersists data in the cache, uniquely referenced by the given key with an optional expiration TTL time.
Parameters
-
string$key -
mixed$value -
DateInterval|int|null$ttl optional
Returns
boolsetConfig() ¶ 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.
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mixed|null$value optional The value to set.
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bool$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 -
DateInterval|int|null$ttl optional
Returns
boolwarning() ¶ 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 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.
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.prefixPrefix appended to all entries. Good for when you need to share a keyspace with either another cache config or another application.warnOnWriteFailuresSome engines, such as ApcuEngine, may raise warnings on write failures.
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