Class DispatcherFilter
This abstract class represents a filter to be applied to a dispatcher cycle. It acts as an event listener with the ability to alter the request or response as needed before it is handled by a controller or after the response body has already been built.
Subclasses of this class use a class naming convention having a Filter suffix.
Limiting filters to specific paths
By using the for option you can limit with request paths a filter is applied to.
Both the before and after event will have the same conditions applied to them. For
example, if you only wanted a filter applied to blog requests you could do:
$filter = new BlogFilter(['for' => '/blog']);When the above filter is connected to a dispatcher it will only fire
its beforeDispatch and afterDispatch methods on requests that start with /blog.
The for condition can also be a regular expression by using the preg: prefix:
$filter = new BlogFilter(['for' => 'preg:#^/blog/\d+$#']);Limiting filters based on conditions
In addition to simple path based matching you can use a closure to match on arbitrary request or response conditions. For example:
$cookieMonster = new CookieFilter([
'when' => function ($req, $res) {
// Custom code goes here.
}
]);If your when condition returns true the before/after methods will be called.
When using the for or when matchers, conditions will be re-checked on the before and after
callback as the conditions could change during the dispatch cycle.
Property Summary
-
$_config protected
arrayRuntime config
-
$_configInitialized protected
boolWhether the config property has already been configured with defaults
-
$_defaultConfig protected
arrayDefault config
-
$_priority protected
intDefault priority for all methods in this filter
Method Summary
-
__construct() public
Constructor.
-
_configDelete() protected
Delete a single config key
-
_configRead() protected
Read a config variable
-
_configWrite() protected
Write a config variable
-
afterDispatch() public
Method called after the controller served a request and generated a response. It is possible to alter the response object at this point as it is not sent to the client yet.
-
beforeDispatch() public
Method called before the controller is instantiated and called to serve a request. If used with default priority, it will be called after the Router has parsed the URL and set the routing params into the request object.
-
config() public
Usage
-
configShallow() public
Merge provided config with existing config. Unlike
config()which does a recursive merge for nested keys, this method does a simple merge. -
handle() public
Handler method that applies conditions and resolves the correct method to call.
-
implementedEvents() public
Returns the list of events this filter listens to. Dispatcher notifies 2 different events
Dispatcher.beforeandDispatcher.after. By default this class will attachpreDispatchandpostDispatchmethod respectively. -
matches() public
Check to see if the incoming request matches this filter's criteria.
Method Detail
__construct() ¶ public
__construct(array $config = [])Constructor.
Parameters
-
array$config optional Settings for the filter.
Throws
InvalidArgumentExceptionWhen 'when' conditions are not callable.
_configDelete() ¶ protected
_configDelete(string $key): voidDelete a single config key
Parameters
-
string$key Key to delete.
Returns
voidThrows
Cake\Core\Exception\Exceptionif attempting to clobber existing config
_configRead() ¶ protected
_configRead(string|null $key): mixedRead a config variable
Parameters
-
string|null$key Key to read.
Returns
mixed_configWrite() ¶ protected
_configWrite(string|array $key, mixed $value, bool|string $merge = false): voidWrite a config variable
Parameters
-
string|array$key Key to write to.
-
mixed$value Value to write.
-
bool|string$merge optional True to merge recursively, 'shallow' for simple merge, false to overwrite, defaults to false.
Returns
voidThrows
Cake\Core\Exception\Exceptionif attempting to clobber existing config
afterDispatch() ¶ public
afterDispatch(Cake\Event\Event $event): voidMethod called after the controller served a request and generated a response. It is possible to alter the response object at this point as it is not sent to the client yet.
If false is returned, the event will be stopped and no more listeners will be notified.
Alternatively you can call $event->stopPropagation() to achieve the same result.
Parameters
-
Cake\Event\Event$event container object having the
requestandresponsekeys in the data property.
Returns
voidbeforeDispatch() ¶ public
beforeDispatch(Cake\Event\Event $event): voidMethod called before the controller is instantiated and called to serve a request. If used with default priority, it will be called after the Router has parsed the URL and set the routing params into the request object.
If a Cake\Network\Response object instance is returned, it will be served at the end of the event cycle, not calling any controller as a result. This will also have the effect of not calling the after event in the dispatcher.
If false is returned, the event will be stopped and no more listeners will be notified.
Alternatively you can call $event->stopPropagation() to achieve the same result.
Parameters
-
Cake\Event\Event$event container object having the
request,responseandadditionalParamskeys in the data property.
Returns
voidconfig() ¶ public
config(string|array|null $key = null, mixed|null $value = null, bool $merge = true): mixedUsage
Reading the whole config:
$this->config();Reading a specific value:
$this->config('key');Reading a nested value:
$this->config('some.nested.key');Setting a specific value:
$this->config('key', $value);Setting a nested value:
$this->config('some.nested.key', $value);Updating multiple config settings at the same time:
$this->config(['one' => 'value', 'another' => 'value']);Parameters
-
string|array|null$key optional The key to get/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
mixedThrows
Cake\Core\Exception\ExceptionWhen trying to set a key that is invalid.
configShallow() ¶ public
configShallow(string|array $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->config('key', $value);Setting a nested value:
$this->config('some.nested.key', $value);Updating multiple config settings at the same time:
$this->config(['one' => 'value', 'another' => 'value']);Parameters
-
string|array$key The key to set, or a complete array of configs.
-
mixed|null$value optional The value to set.
Returns
$thishandle() ¶ public
handle(Cake\Event\Event $event): mixedHandler method that applies conditions and resolves the correct method to call.
Parameters
-
Cake\Event\Event$event The event instance.
Returns
mixedimplementedEvents() ¶ public
implementedEvents(): arrayReturns the list of events this filter listens to.
Dispatcher notifies 2 different events Dispatcher.before and Dispatcher.after.
By default this class will attach preDispatch and postDispatch method respectively.
Override this method at will to only listen to the events you are interested in.
Returns
arraymatches() ¶ public
matches(Cake\Event\Event $event): boolCheck to see if the incoming request matches this filter's criteria.
Parameters
-
Cake\Event\Event$event The event to match.
Returns
boolProperty Detail
$_configInitialized ¶ protected
Whether the config property has already been configured with defaults
Type
bool$_defaultConfig ¶ protected
Default config
These are merged with user-provided config when the class is used. The when and for options allow you to define conditions that are checked before your filter is called.
Type
array