CacheEngine
in package
implements
CacheInterface, CacheEngineInterface
uses
InstanceConfigTrait
Storage engine for CakePHP caching
Table of Contents
Interfaces
- CacheInterface
- CacheEngineInterface
- Interface for cache engines that defines methods outside of the PSR16 interface that are used by `Cache`.
Constants
- CHECK_KEY = 'key'
- CHECK_VALUE = 'value'
Properties
- $_config : array<string, mixed>
- Runtime config
- $_configInitialized : bool
- Whether the config property has already been configured with defaults
- $_defaultConfig : 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.
- $_groupPrefix : string
- Contains the compiled string with all group prefixes to be prepended to every key in this cache engine
Methods
- add() : bool
- Add a key to the cache if it does not already exist.
- clear() : bool
- Delete all keys from the cache
- clearGroup() : bool
- 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.
- configShallow() : $this
- Merge provided config with existing config. Unlike `config()` which does a recursive merge for nested keys, this method does a simple merge.
- decrement() : int|false
- Decrement a number under the key and return decremented value
- delete() : bool
- Delete a key from the cache
- deleteMultiple() : bool
- Deletes multiple cache items as a list
- get() : mixed
- Fetches the value for a given key from the cache.
- getConfig() : mixed
- Returns the config.
- getConfigOrFail() : mixed
- Returns the config for this specific key.
- getMultiple() : iterable<string|int, mixed>
- Obtains multiple cache items by their unique keys.
- groups() : array<string|int, 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
- has() : bool
- Determines whether an item is present in the cache.
- increment() : int|false
- Increment a number under the key and return incremented value
- init() : bool
- Initialize the cache engine
- set() : bool
- Persists data in the cache, uniquely referenced by the given key with an optional expiration TTL time.
- setConfig() : $this
- Sets the config.
- setMultiple() : bool
- Persists a set of key => value pairs in the cache, with an optional TTL.
- _configDelete() : void
- Deletes a single config key.
- _configRead() : mixed
- Reads a config key.
- _configWrite() : void
- Writes a config key.
- _key() : string
- Generates a key for cache backend usage.
- duration() : int
- Convert the various expressions of a TTL value into duration in seconds
- ensureValidKey() : void
- Ensure the validity of the given cache key.
- ensureValidType() : void
- Ensure the validity of the argument type and cache keys.
- warning() : void
- Cache Engines may trigger warnings if they encounter failures during operation, if option warnOnWriteFailures is set to true.
Constants
CHECK_KEY
protected
string
CHECK_KEY
= 'key'
CHECK_VALUE
protected
string
CHECK_VALUE
= 'value'
Properties
$_config
Runtime config
protected
array<string, mixed>
$_config
= []
$_configInitialized
Whether the config property has already been configured with defaults
protected
bool
$_configInitialized
= false
$_defaultConfig
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.
protected
array<string, mixed>
$_defaultConfig
= ['duration' => 3600, 'groups' => [], 'prefix' => 'cake_', 'warnOnWriteFailures' => true]
-
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. -
warnOnWriteFailures
Some engines, such as ApcuEngine, may raise warnings on write failures.
$_groupPrefix
Contains the compiled string with all group prefixes to be prepended to every key in this cache engine
protected
string
$_groupPrefix
= ''
Methods
add()
Add a key to the cache if it does not already exist.
public
add(string $key, mixed $value) : bool
Defaults to a non-atomic implementation. Subclasses should prefer atomic implementations.
Parameters
- $key : string
-
Identifier for the data.
- $value : mixed
-
Data to be cached.
Return values
bool —True if the data was successfully cached, false on failure.
clear()
Delete all keys from the cache
public
abstract clear() : bool
Return values
bool —True if the cache was successfully cleared, false otherwise
clearGroup()
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.
public
abstract clearGroup(string $group) : bool
Parameters
- $group : string
-
name of the group to be cleared
Return values
boolconfigShallow()
Merge provided config with existing config. Unlike `config()` which does a recursive merge for nested keys, this method does a simple merge.
public
configShallow(array<string, mixed>|string $key[, mixed|null $value = null ]) : $this
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
- $key : array<string, mixed>|string
-
The key to set, or a complete array of configs.
- $value : mixed|null = null
-
The value to set.
Return values
$thisdecrement()
Decrement a number under the key and return decremented value
public
abstract decrement(string $key[, int $offset = 1 ]) : int|false
Parameters
- $key : string
-
Identifier for the data
- $offset : int = 1
-
How much to subtract
Return values
int|false —New incremented value, false otherwise
delete()
Delete a key from the cache
public
abstract delete(string $key) : bool
Parameters
- $key : string
-
Identifier for the data
Return values
bool —True if the value was successfully deleted, false if it didn't exist or couldn't be removed
deleteMultiple()
Deletes multiple cache items as a list
public
deleteMultiple(iterable<string|int, mixed> $keys) : bool
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
- $keys : iterable<string|int, mixed>
-
A list of string-based keys to be deleted.
Tags
Return values
bool —True if the items were successfully removed. False if there was an error.
get()
Fetches the value for a given key from the cache.
public
abstract get(string $key[, mixed $default = null ]) : mixed
Parameters
- $key : string
-
The unique key of this item in the cache.
- $default : mixed = null
-
Default value to return if the key does not exist.
Tags
Return values
mixed —The value of the item from the cache, or $default in case of cache miss.
getConfig()
Returns the config.
public
getConfig([string|null $key = null ][, mixed $default = null ]) : mixed
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
- $key : string|null = null
-
The key to get or null for the whole config.
- $default : mixed = null
-
The return value when the key does not exist.
Return values
mixed —Configuration data at the named key or null if the key does not exist.
getConfigOrFail()
Returns the config for this specific key.
public
getConfigOrFail(string $key) : mixed
The config value for this key must exist, it can never be null.
Parameters
- $key : string
-
The key to get.
Tags
Return values
mixed —Configuration data at the named key
getMultiple()
Obtains multiple cache items by their unique keys.
public
getMultiple(iterable<string|int, mixed> $keys[, mixed $default = null ]) : iterable<string|int, mixed>
Parameters
- $keys : iterable<string|int, mixed>
-
A list of keys that can obtained in a single operation.
- $default : mixed = null
-
Default value to return for keys that do not exist.
Tags
Return values
iterable<string|int, mixed> —A list of key value pairs. Cache keys that do not exist or are stale will have $default as value.
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
public
groups() : array<string|int, string>
Return values
array<string|int, string>has()
Determines whether an item is present in the cache.
public
has(string $key) : bool
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
- $key : string
-
The cache item key.
Tags
Return values
boolincrement()
Increment a number under the key and return incremented value
public
abstract increment(string $key[, int $offset = 1 ]) : int|false
Parameters
- $key : string
-
Identifier for the data
- $offset : int = 1
-
How much to add
Return values
int|false —New incremented value, false otherwise
init()
Initialize the cache engine
public
init([array<string, mixed> $config = [] ]) : bool
Called automatically by the cache frontend. Merge the runtime config with the defaults before use.
Parameters
- $config : array<string, mixed> = []
-
Associative array of parameters for the engine
Return values
bool —True if the engine has been successfully initialized, false if not
set()
Persists data in the cache, uniquely referenced by the given key with an optional expiration TTL time.
public
abstract set(string $key, mixed $value[, DateInterval|int|null $ttl = null ]) : bool
Parameters
- $key : string
-
The key of the item to store.
- $value : mixed
-
The value of the item to store, must be serializable.
- $ttl : DateInterval|int|null = null
-
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.
Tags
Return values
bool —True on success and false on failure.
setConfig()
Sets the config.
public
setConfig(array<string, mixed>|string $key[, mixed|null $value = null ][, bool $merge = true ]) : $this
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
- $key : array<string, mixed>|string
-
The key to set, or a complete array of configs.
- $value : mixed|null = null
-
The value to set.
- $merge : bool = true
-
Whether to recursively merge or overwrite existing config, defaults to true.
Tags
Return values
$thissetMultiple()
Persists a set of key => value pairs in the cache, with an optional TTL.
public
setMultiple(iterable<string|int, mixed> $values[, DateInterval|int|null $ttl = null ]) : bool
Parameters
- $values : iterable<string|int, mixed>
-
A list of key => value pairs for a multiple-set operation.
- $ttl : DateInterval|int|null = null
-
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.
Tags
Return values
bool —True on success and false on failure.
_configDelete()
Deletes a single config key.
protected
_configDelete(string $key) : void
Parameters
- $key : string
-
Key to delete.
Tags
_configRead()
Reads a config key.
protected
_configRead(string|null $key) : mixed
Parameters
- $key : string|null
-
Key to read.
_configWrite()
Writes a config key.
protected
_configWrite(array<string, mixed>|string $key, mixed $value[, string|bool $merge = false ]) : void
Parameters
- $key : array<string, mixed>|string
-
Key to write to.
- $value : mixed
-
Value to write.
- $merge : string|bool = false
-
True to merge recursively, 'shallow' for simple merge, false to overwrite, defaults to false.
Tags
_key()
Generates a key for cache backend usage.
protected
_key(string $key) : string
If the requested key is valid, the group prefix value and engine prefix are applied. Whitespace in keys will be replaced.
Parameters
- $key : string
-
the key passed over
Tags
Return values
string —Prefixed key with potentially unsafe characters replaced.
duration()
Convert the various expressions of a TTL value into duration in seconds
protected
duration(DateInterval|int|null $ttl) : int
Parameters
- $ttl : DateInterval|int|null
-
The TTL value of this item. If null is sent, the driver's default duration will be used.
Return values
intensureValidKey()
Ensure the validity of the given cache key.
protected
ensureValidKey(string $key) : void
Parameters
- $key : string
-
Key to check.
Tags
ensureValidType()
Ensure the validity of the argument type and cache keys.
protected
ensureValidType(iterable<string|int, mixed> $iterable[, string $check = self::CHECK_VALUE ]) : void
Parameters
- $iterable : iterable<string|int, mixed>
-
The iterable to check.
- $check : string = self::CHECK_VALUE
-
Whether to check keys or values.
Tags
warning()
Cache Engines may trigger warnings if they encounter failures during operation, if option warnOnWriteFailures is set to true.
protected
warning(string $message) : void
Parameters
- $message : string
-
The warning message.