OnDispatch event in Service Constructor - php

Question

I have problem with attaching OnDispatch event in Apigility. I want to have value from custom header in constructor of my abstract Service Class. It works when I simply add it to on bootstrap in Module.php
public function onBootstrap(MvcEvent $e)
{
$eventManager = $e->getApplication()->getEventManager();
$moduleRouteListener = new ModuleRouteListener();
$moduleRouteListener->attach($eventManager);
$eventManager->attach(\Zend\Mvc\MvcEvent::EVENT_DISPATCH, array($this, 'onDispatch'));
}
public function onDispatch(\Zend\Mvc\MvcEvent $e){
$e->getRequest()->getHeaders()->get('User-Token')->getFieldValue();
}
But I don't know how to pass this value to ServiceAbstract Constructor.
I also tried with implementing EventManagerAwareInterface and attaching events with attachDefaultListeners() method but that didn't get me any results - attached function was not called. What is the proper approach to attaching to events NOT in controllers? Thanks for any help.

Answer 1

It seems to me that you have two different goals here.
1. Store a header variable from a route event.
2. Get a variable into the constructor function of a class
To answer 1.
You can make a listener class and attach this class to your eventManager. This would look something like this:
<?php
namespace My\Listener;
use Zend\EventManager\ListenerAggregateInterface;
use Zend\EventManager\EventManagerInterface;
use Zend\Mvc\MvcEvent;
use Zend\Http\Headers;
use Zend\Http\Request as HttpRequest;
class MyCustomListener implements ListenerAggregateInterface
{
/**
* #var \Zend\Stdlib\CallbackHandler[]
*/
protected $listeners = array();
/**
* #param EventManagerInterface $eventManager
*/
public function attach(EventManagerInterface $eventManager)
{
// attach on route
$this->listeners[] = $eventManager->attach(MvcEvent::EVENT_DISPATCH, array($this, 'onDispatch'));
}
/**
* #param EventManagerInterface $eventManager
*/
public function detach(EventManagerInterface $eventManager)
{
foreach ($this->listeners as $index => $listener) {
if ($eventManager->detach($listener)) {
unset($this->listeners[$index]);
}
}
}
/**
* Do your thing on dispatch event with your headers
*
* #param MvcEvent $event
*/
public function onDispatch(MvcEvent $event)
{
$request = $event->getRequest();
if(!$request instanceof HttpRequest){
// Nothing to do
return;
}
$headers = $request->getHeaders();
// You could for example get a service here and store your value
}
}
You attach this listener in Module.php like this:
public function onBootstrap(MvcEvent $event)
{
$event->getApplication();
$application->getEventManager();
$eventManager->attach($serviceManager->get('My\Listener\MyCustomListener'));
}
You have to register your listener in your ServiceManager either under invokables or factories with the key My\Listener\MyCustomListener to be able to attach it here like this.
To answer 2:
To get a variable in your constructor you can make a factory for your class and get the variable from the service that holds the variable that you need (could be from the listener from 1 directly).
<?php
namespace My\Factory;
use Zend\ServiceManager\FactoryInterface;
use Zend\ServiceManager\ServiceLocatorInterface;
use My\Folder\MyCustomClass;
class MyClassFactory implements FactoryInterface
{
/**
* #param ServiceLocatorInterface $serviceLocator
* #return Logger
*/
public function createService(ServiceLocatorInterface $serviceLocator)
{
$controllerPluginManager = $serviceLocator;
$service = $serviceManager->get(My\Service\MyStorageService);
$dependency = $service->getDependency();
return new MyCustomClass($dependency);
}
}