Creating a block; "the options do not exist" - symfony

Question

Working on a project using Symfony and the CMF bundle. I followed the documentation in creating your own block.
However, when rendering the block, Symfony throws an exception telling me that the specified options do not exist.
An exception has been thrown during the rendering of a template ("The options "title", "url" do not exist. Known options are: "attr", "extra_cache_keys", "template", "ttl", "use_cache"") in FooMainBundle::Page/Standard.html.twig at line 15.
This is my template (Standard.html.twig):
{% extends "FooMainBundle::layout.html.twig" %}
{% block content %}
{{ sonata_block_render({'name': 'rssBlock'}, {
'title': 'Symfony CMF news',
'url': 'http://cmf.symfony.com/news.rss'
}) }}
{% endblock %}
This is my Document:
<?php
namespace Foo\BarContentBundle\Document;
use Doctrine\ODM\PHPCR\Mapping\Annotations as PHPCR;
use Symfony\Cmf\Bundle\BlockBundle\Doctrine\Phpcr\AbstractBlock;
/**
* #PHPCR\Document(referenceable=true)
*/
class RssBlock extends AbstractBlock
{
/**
* #PHPCR\String(nullable=true)
*/
private $feedUrl;
/**
* #PHPCR\String()
*/
private $title;
public function getType()
{
return 'foo_barcontent.block.rss';
}
public function getOptions()
{
$options = array(
'title' => $this->title,
);
if ($this->feedUrl) {
$options['url'] = $this->feedUrl;
}
return $options;
}
public function getTitle() {
return $this->title;
}
public function setTitle($title) {
$this->title = $title;
}
public function getFeedUrl() {
return $this->feedUrl;
}
public function setFeedUrl($feedUrl) {
$this->feedUrl = $feedUrl;
}
}
This is my service:
use Symfony\Component\HttpFoundation\Response;
use Symfony\Component\OptionsResolver\OptionsResolverInterface;
use Sonata\AdminBundle\Form\FormMapper;
use Sonata\AdminBundle\Validator\ErrorElement;
use Sonata\BlockBundle\Model\BlockInterface;
use Sonata\BlockBundle\Block\BlockContextInterface;
use Sonata\BlockBundle\Block\BaseBlockService;
class RssBlockService extends BaseBlockService
{
public function getName()
{
return 'Rss Reader';
}
/**
* Define valid options for a block of this type.
*/
public function setDefaultSettings(OptionsResolverInterface $resolver)
{
$resolver->setDefaults(array(
'url' => false,
'title' => 'Feed items',
'template' => 'FooBarContentBundle:Block:block_rss.html.twig',
));
}
/**
* The block context knows the default settings, but they can be
* overwritten in the call to render the block.
*/
public function execute(BlockContextInterface $blockContext, Response $response = null)
{
$block = $blockContext->getBlock();
if (!$block->getEnabled()) {
return new Response();
}
// merge settings with those of the concrete block being rendered
$settings = $blockContext->getSettings();
$resolver = new OptionsResolver();
$resolver->setDefaults($settings);
$settings = $resolver->resolve($block->getOptions());
$feeds = false;
if ($settings['url']) {
$options = array(
'http' => array(
'user_agent' => 'Sonata/RSS Reader',
'timeout' => 2,
)
);
// retrieve contents with a specific stream context to avoid php errors
$content = #file_get_contents($settings['url'], false, stream_context_create($options));
if ($content) {
// generate a simple xml element
try {
$feeds = new \SimpleXMLElement($content);
$feeds = $feeds->channel->item;
} catch (\Exception $e) {
// silently fail error
}
}
}
return $this->renderResponse($blockContext->getTemplate(), array(
'feeds' => $feeds,
'block' => $blockContext->getBlock(),
'settings' => $settings
), $response);
}
// These methods are required by the sonata block service interface.
// They are not used in the CMF. To edit, create a symfony form or
// a sonata admin.
public function buildEditForm(FormMapper $formMapper, BlockInterface $block)
{
throw new \Exception();
}
public function validateBlock(ErrorElement $errorElement, BlockInterface $block)
{
throw new \Exception();
}
}
And I placed this in my services.xml:
<service id="foo_barcontent.block.rss" class="Foo\BarBundle\Block\RssBlockService">
<tag name="sonata.block" />
<argument>foo_barcontent.block.rss</argument>
<argument type="service" id="templating" />
</service>