Action View Helper

Action.php

<?php
/**
 * IGN Application Module
 *
 * @category   Application
 * @package    Application_View
 * @copyright  Copyright (c) 2006-2011 IGN Entertainment, Inc. (http://corp.ign.com/)
 */

namespace Application\View\Helper;

use Zend\Di\Locator,
    Zend\Http\PhpEnvironment\Request,
    Zend\Mvc\Controller\ActionController,
    Zend\Mvc\MvcEvent,
    Zend\Mvc\Router\Http\RouteMatch,
    Zend\View,
    Zend\View\Exception,
    Zend\View\Helper;

/**
 * Helper for rendering output of a controller action
 * @category   Application
 * @package    Application_View
 * @copyright  Copyright (c) 2006-2011 IGN Entertainment, Inc. (http://corp.ign.com/)
 */
class Action extends Helper\AbstractHelper
{

    /**
     * @var \Zend\Di\Locator
     */
    protected $locator;

    /**
     * Set locator instance
     *
     * @param  Di $locator
     * @return void
     */
    public function setLocator(Locator $locator)
    {
        $this->locator = $locator;
    }

    /**
     * Dispatch a controller action and render using view
     * If the action results in anything besides a View Model, return empty string.
     *
     * In standalone mode, it validates the client supports ESI
     * If so, it returns an ESI include tag
     *
     * @param  string $action
     * @param  string $controller
     * @param  string $module Defaults to default module
     * @param  array $params
     * @throws Zend\View\Exception\RuntimeException
     * @return string
     */
    public function __invoke($action, $controller, array $params = array(), $standaloneRouteName = false)
    {
        if (!$this->locator instanceof Locator) {
            throw new Exception\RuntimeException('No Locator provided');
        }

        // uniqid ensures we don't get a shared instance
        $controllerObject = $this->locator->get($controller, array('uniqid' => uniqid()));
        if (!$controllerObject instanceof ActionController) {
            throw new Exception\RuntimeException('Invalid controller');
        }

        $actionMethod = $controllerObject->getMethodFromAction($action);
        if (!method_exists($controllerObject, $actionMethod)) {
            throw new Exception\RuntimeException('Invalid action');
        }

        $request = new Request();

        if ($standaloneRouteName) {
            $headers = $request->headers();
            if ($headers->has('surrogate-capability') && $headers->get('surrogate-capability')->getFieldValue() == 'ESI/1.0') {
                try {
                    $url = $this->view->url($standaloneRouteName, $params);
                } catch (\Zend\Mvc\Router\Exception\RuntimeException $e) {
                    throw new Exception\RuntimeException('Invalid stand-alone route');
                }
                return '<esi:include src="'
                    . \Zend\Uri\Uri::merge($request->uri(), $url)
                    . '" onerror="continue"/>';
            }
        }

        $routeMatch = new RouteMatch(
            array_merge(
                $params,
                array('controller' => $controller, 'action' => $action)
            )
        );
        $e = new MvcEvent();
        $e->setRouter($this->locator->get('Zend\Mvc\Router\RouteStack'));
        $e->setRouteMatch($routeMatch);
        $controllerObject->setEvent($e);
        $request->query()->fromArray($params);
        $result = $controllerObject->dispatch($request);
        if ($result instanceof \Zend\View\Model) {
            return $this->view->render($result);
        }
        return '';
    }
}