Controller Plugins

When using the AbstractActionController or AbstractRestfulController, or if you implement the setPluginManager method in your custom controllers, you have access to a number of pre-built plugins. Additionally, you can register your own custom plugins with the manager.

The built-in plugins are:

• Zend\Mvc\Controller\Plugin\AcceptableViewModelSelector
• Zend\Mvc\Controller\Plugin\FlashMessenger
• Zend\Mvc\Controller\Plugin\Forward
• Zend\Mvc\Controller\Plugin\Identity
• Zend\Mvc\Controller\Plugin\Layout
• Zend\Mvc\Controller\Plugin\Params
• Zend\Mvc\Controller\Plugin\PostRedirectGet
• Zend\Mvc\Controller\Plugin\Redirect
• Zend\Mvc\Controller\Plugin\Url

If your controller implements the setPluginManager, getPluginManager and plugin methods, you can access these using their shortname via the plugin() method:

$plugin = $this->plugin('url');

For an extra layer of convenience, both AbstractActionController and AbstractRestfulController have __call() implementations that allow you to retrieve plugins via method calls:

$plugin = $this->url();

AcceptableViewModelSelector Plugin

The AcceptableViewModelSelector is a helper that can be used to select an appropriate view model based on user defined criteria will be tested against the Accept header in the request.

As an example:

use Zend\Mvc\Controller\AbstractActionController;
use Zend\View\Model\JsonModel;

class SomeController extends AbstractActionController
{
   protected $acceptCriteria = array(
      'Zend\View\Model\JsonModel' => array(
         'application/json',
      ),
      'Zend\View\Model\FeedModel' => array(
         'application/rss+xml',
      ),
   );

   public function apiAction()
   {
      $viewModel = $this->acceptableViewModelSelector($this->acceptCriteria);

      // Potentially vary execution based on model returned
      if ($viewModel instanceof JsonModel) {
         // ...
      }
   }
}

The above would return a standard Zend\View\Model\ViewModel instance if the criteria is not met, and the specified view model types if the specific criteria is met. Rules are matched in order, with the first match “winning.”

FlashMessenger Plugin

The FlashMessenger is a plugin designed to create and retrieve self-expiring, session-based messages. It exposes a number of methods:

setSessionManager(Zend\Session\ManagerInterface $manager)

Allows you to specify an alternate session manager, if desired.

Return type:Zend\Mvc\Controller\Plugin\FlashMessenger

getSessionManager()

Allows you to retrieve the session manager registered.

Return type:Zend\Session\ManagerInterface

getContainer()

Returns the Zend\Session\Container instance in which the flash messages are stored.

Return type:Zend\Session\Container

setNamespace(string $namespace = 'default')

Allows you to specify a specific namespace in the container in which to store or from which to retrieve flash messages.

Return type:Zend\Mvc\Controller\Plugin\FlashMessenger

• getNamespace() retrieves the name of the flash message namespace.

getNamespace()

Retrieves the name of the flash message namespace.

Return type:string

addMessage(string $message)

Allows you to add a message to the current namespace of the session container.

Return type:Zend\Mvc\Controller\Plugin\FlashMessenger

hasMessages()

Lets you determine if there are any flash messages from the current namespace in the session container.

Return type:boolean

getMessages()

Retrieves the flash messages from the current namespace of the session container

Return type:array

clearMessages()

Clears all flash messages in current namespace of the session container. Returns true if messages were cleared, false if none existed.

Return type:boolean

hasCurrentMessages()

Indicates whether any messages were added during the current request.

Return type:boolean

getCurrentMessages()

Retrieves any messages added during the current request.

Return type:array

clearCurrentMessages()

Removes any messages added during the current request. Returns true if current messages were cleared, false if none existed.

Return type:boolean

Additionally, the FlashMessenger implements both IteratorAggregate and Countable, allowing you to iterate over and count the flash messages in the current namespace within the session container.

Examples

public function processAction()
{
    // ... do some work ...
    $this->flashMessenger()->addMessage('You are now logged in.');
    return $this->redirect()->toRoute('user-success');
}

public function successAction()
{
    $return = array('success' => true);
    $flashMessenger = $this->flashMessenger();
    if ($flashMessenger->hasMessages()) {
        $return['messages'] = $flashMessenger->getMessages();
    }
    return $return;
}

Forward Plugin

Occasionally, you may want to dispatch additional controllers from within the matched controller – for instance, you might use this approach to build up “widgetized” content. The Forward plugin helps enable this.

For the Forward plugin to work, the controller calling it must be ServiceLocatorAware; otherwise, the plugin will be unable to retrieve a configured and injected instance of the requested controller.

The plugin exposes a single method, dispatch(), which takes two arguments:

• $name, the name of the controller to invoke. This may be either the fully qualified class name, or an alias defined and recognized by the ServiceManager instance attached to the invoking controller.
• $params is an optional array of parameters with which to see a RouteMatch object for purposes of this specific request. Meaning the parameters will be matched by their key to the routing identifiers in the config (otherwise non-matching keys are ignored)

Forward returns the results of dispatching the requested controller; it is up to the developer to determine what, if anything, to do with those results. One recommendation is to aggregate them in any return value from the invoking controller.

As an example:

$foo = $this->forward()->dispatch('foo', array('action' => 'process'));
return array(
    'somekey' => $somevalue,
    'foo'     => $foo,
);

Identity Plugin

The Identity plugin allows for getting the identity from the AuthenticationService.

For the Identity plugin to work, a Zend\Authentication\AuthenticationService name or alias must be defined and recognized by the ServiceManager.

Identity returns the identity in the AuthenticationService or null if no identity is available.

As an example:

public function testAction()
{
    if ($user = $this->identity()) {
         // someone is logged !
    } else {
         // not logged in
    }
}

When invoked, the Identity plugin will look for a service by the name or alias Zend\Authentication\AuthenticationService in the ServiceManager. You can provide this service to the ServiceManager in a configuration file:

// In a configuration file...
return array(
    'service_manager' => array(
        'aliases' => array(
            'Zend\Authentication\AuthenticationService' => 'my_auth_service',
        ),
        'invokables' => array(
            'my_auth_service' => 'Zend\Authentication\AuthenticationService',
        ),
    ),
);

The Identity plugin exposes two methods:

setAuthenticationService(Zend\Authentication\AuthenticationService $authenticationService)

Sets the authentication service instance to be used by the plugin.

Return type:void

getAuthenticationService()

Retrieves the current authentication service instance if any is attached.

Return type:Zend\Authentication\AuthenticationService

Layout Plugin

The Layout plugin allows for changing layout templates from within controller actions.

It exposes a single method, setTemplate(), which takes one argument:

• $template, the name of the template to set.

As an example:

$this->layout()->setTemplate('layout/newlayout');

It also implements the __invoke magic method, which allows for even easier setting of the template:

$this->layout('layout/newlayout');

Params Plugin

The Params plugin allows for accessing parameters in actions from different sources.

It exposes several methods, one for each parameter source:

fromFiles(string $name = null, mixed $default = null)

For retrieving all or one single file. If $name is null, all files will be returned.

Return type:array|ArrayAccess|null

fromHeader(string $header = null, mixed $default = null)

For retrieving all or one single header parameter. If $header is null, all header parameters will be returned.

Return type:null|Zend\Http\Header\HeaderInterface

fromPost(string $param = null, mixed $default = null)

For retrieving all or one single post parameter. If $param is null, all post parameters will be returned.

Return type:mixed

fromQuery(string $param = null, mixed $default = null)

For retrieving all or one single query parameter. If $param is null, all query parameters will be returned.

Return type:mixed

fromRoute(string $param = null, mixed $default = null)

For retrieving all or one single route parameter. If $param is null, all route parameters will be returned.

Return type:mixed

It also implements the __invoke magic method, which allows for short circuiting to the fromRoute method:

$this->params()->fromRoute('param', $default);
// or
$this->params('param', $default);

Post/Redirect/Get Plugin

When a user sends a POST request (e.g. after submitting a form), their browser will try to protect them from sending the POST again, breaking the back button, causing browser warnings and pop-ups, and sometimes reposting the form. Instead, when receiving a POST, we should store the data in a session container and redirect the user to a GET request.

This plugin can be invoked with two arguments:

• $redirect, a string containing the redirect location which can either be a named route or a URL, based on the contents of the second parameter.
• $redirectToUrl, a boolean that when set to TRUE, causes the first parameter to be treated as a URL instead of a route name (this is required when redirecting to a URL instead of a route). This argument defaults to false.

When no arguments are provided, the current matched route is used.

Example Usage

// Pass in the route/url you want to redirect to after the POST
$prg = $this->prg('/user/register', true);

if ($prg instanceof \Zend\Http\PhpEnvironment\Response) {
    // returned a response to redirect us
    return $prg;
} elseif ($prg === false) {
    // this wasn't a POST request, but there were no params in the flash messenger
    // probably this is the first time the form was loaded
    return array('form' => $myForm);
}

// $prg is an array containing the POST params from the previous request
$form->setData($prg);

// ... your form processing code here

File Post/Redirect/Get Plugin

While similar to the standard Post/Redirect/Get Plugin, the File PRG Plugin will work for forms with file inputs. The difference is in the behavior: The File PRG Plugin will interact directly with your form instance and the file inputs, rather than only returning the POST params from the previous request.

By interacting directly with the form, the File PRG Plugin will turn off any file inputs’ required flags for already uploaded files (for a partially valid form state), as well as run the file input filters to move the uploaded files into a new location (configured by the user).

Warning

You must attach a Filter for moving the uploaded files to a new location, such as the RenameUpload Filter, or else your files will be removed upon the redirect.

This plugin can be invoked with three arguments:

• $form: the form instance.
• $redirect: (Optional) a string containing the redirect location which can either be a named route or a URL, based on the contents of the third parameter. If this argument is not provided, it will default to the current matched route.
• $redirectToUrl: (Optional) a boolean that when set to TRUE, causes the second parameter to be treated as a URL instead of a route name (this is required when redirecting to a URL instead of a route). This argument defaults to false.

Example Usage

$myForm = new Zend\Form\Form('my-form');
$myForm->add(array(
    'type' => 'Zend\Form\Element\File',
    'name' => 'file',
));
// NOTE: Without a filter to move the file,
//       our files will disappear between the requests
$myForm->getInputFilter()->getFilterChain()->attach(
    new Zend\Filter\File\RenameUpload(array(
        'target'    => './data/tmpuploads/file',
        'randomize' => true,
    ))
);

// Pass in the route/url you want to redirect to after the POST
$prg = $this->prg($myForm, '/user/profile-pic', true);

if ($prg instanceof \Zend\Http\PhpEnvironment\Response) {
    // Returned a response to redirect us
    return $prg;
} elseif ($prg === false) {
    // First time the form was loaded
    return array('form' => $myForm);
}

// Form was submitted.
// $prg is now an array containing the POST params from the previous request,
// but we don't have to apply it to the form since that has already been done.

// Process the form
if ($form->isValid()) {
    // ...Save the form...
    return $this->redirect()->toRoute('/user/profile-pic/success');
} else {
    // Form not valid, but file uploads might be valid and uploaded
    $fileErrors = $form->get('file')->getMessages();
    if (empty($fileErrors)) {
        $tempFile = $form->get('file')->getValue();
    }
}

Redirect Plugin

Redirections are quite common operations within applications. If done manually, you will need to do the following steps:

• Assemble a url using the router
• Create and inject a “Location” header into the Response object, pointing to the assembled URL
• Set the status code of the Response object to one of the 3xx HTTP statuses.

The Redirect plugin does this work for you. It offers three methods:

toRoute(string $route = null, array $params = array(), array $options = array(), boolean $reuseMatchedParams = false)

Redirects to a named route, using the provided $params and $options to assembled the URL.

Return type:Zend\Http\Response

toUrl(string $url)

Simply redirects to the given URL.

Return type:Zend\Http\Response

refresh()

Refresh to current route

Return type:Zend\Http\Response

In each case, the Response object is returned. If you return this immediately, you can effectively short-circuit execution of the request.

Note

This plugin requires that the controller invoking it implements InjectApplicationEventInterface, and thus has an MvcEvent composed, as it retrieves the router from the event object.

As an example:

return $this->redirect()->toRoute('login-success');

Url Plugin

Often you may want to generate URLs from route definitions within your controllers – in order to seed the view, generate headers, etc. While the MvcEvent object composes the router, doing so manually would require this workflow:

$router = $this->getEvent()->getRouter();
$url    = $router->assemble($params, array('name' => 'route-name'));

The Url helper makes this slightly more convenient:

$url = $this->url()->fromRoute('route-name', $params);

The fromRoute() method is the only public method defined, and has the following signature:

public function fromRoute($route, array $params = array(), array $options = array())

Note

This plugin requires that the controller invoking it implements InjectApplicationEventInterface, and thus has an MvcEvent composed, as it retrieves the router from the event object.