RequestContext.php

<?php

namespace Drupal\Core\Routing;

use Symfony\Component\HttpFoundation\Request;
use Symfony\Component\HttpFoundation\RequestStack;
use Symfony\Component\Routing\RequestContext as SymfonyRequestContext;

/**
 * Holds information about the current request.
 */
class RequestContext extends SymfonyRequestContext {
    
    /**
     * The scheme, host and base path, for example "http://example.com/d8".
     *
     * @var string
     */
    protected $completeBaseUrl;
    
    /**
     * Populates the context from the current request from the request stack.
     *
     * @param \Symfony\Component\HttpFoundation\RequestStack $request_stack
     *   The current request stack.
     */
    public function fromRequestStack(RequestStack $request_stack) {
        $this->fromRequest($request_stack->getCurrentRequest());
    }
    
    /**
     * {@inheritdoc}
     */
    public function fromRequest(Request $request) : static {
        // @todo Extract the code in DrupalKernel::initializeRequestGlobals.
        //   See https://www.drupal.org/node/2404601
        if (isset($GLOBALS['base_url'])) {
            $this->setCompleteBaseUrl($GLOBALS['base_url']);
        }
        return parent::fromRequest($request);
    }
    
    /**
     * Gets the scheme, host and base path.
     *
     * For example, in an installation in a subdirectory "d8", it should be
     * "https://example.com/d8".
     */
    public function getCompleteBaseUrl() {
        return $this->completeBaseUrl;
    }
    
    /**
     * Sets the complete base URL for the Request context.
     *
     * @param string $complete_base_url
     *   The complete base URL.
     */
    public function setCompleteBaseUrl($complete_base_url) {
        $this->completeBaseUrl = $complete_base_url;
    }

}