eZ Publish 5: Is this a viable pattern for handling sub-items of a content object, for example children of a folder?

full.html.twig

{% extends ... %}

{% block content %}
  {# Render the full view of the content object #}
	{% if content.field['title'] is defined %}
		<h1>{{ ez_render_field( content, 'title') }}</h1>
	{% else %}
		<h1>{{ ez_render_field(content, 'name') }}</h1>
	{% endif %}
	{% if content.fields['short_description'] is defined %}
		<div class="attribute-short_description">
			{{ ez_render_field( content, 'short_description') }}
		</div>
	{% endif %}
	{% if content.fields['description'] is defined %}
		<div class="attribute-description">
			{{ ez_render_field( content, 'description') }}
		</div>
	{% endif %}
	
	{# Render sub-items using a sub-request #}
	{{ render( controller( "MyBundle:Default:subItems", {'locationId': location.id }), {'strategy': 'esi'} ) }}
{% endblock %}

line.html.twig

{#
    Render a content object in line view
#}

<div class="class-{{ content.contentInfo.contentTypeId }}">
    <h2><a href="{{ path( 'ez_urlalias', {'locationId': content.contentInfo.mainLocationId} ) }}">{{ ez_render_field( content, 'title') }}</a></h2>

    {% if content.fields['short_description'] is defined %}
        <div class="attribute-short_description">
            {{ ez_render_field( content, 'short_description') }}
        </div>
    {% endif %}
</div>

MyController.php

    /**
     * Renders sub-items of the current location
     * 
     * TODO: add content type filtering, and possibly more
     * TODO: add template to be used for rendering
     *
     * @param int $locationId
     * @return \Symfony\Component\HttpFoundation\Response
     */
    public function subItemsAction( $locationId )
    {
        $response = new Response;
        $response = $this->cacheResponse( $response, $locationId );

        $locationList = $this->fetchLocationListIncludingContentTypes( $locationId, array() );
        $contentList = array();
        foreach ( $locationList as $location )
        {
            $contentList[] = $this->getRepository()->getContentService()->loadContent( $location->contentId );
        }

        return $this->render(
            "WebmanufakturSiteDruckformBundle::sub_items.html.twig",
            array(
                "locationList" => $locationList,
                "contentList" => $contentList
            ),
            $response
        );
    }

    /**
     * Returns list of locations under given parent location, optionally pnly for given content types
     * @param $locationId
     * @param array $includeContentTypes
     * @return array
     */
    private function fetchLocationListIncludingContentTypes( $locationId, array $includeContentTypes = array() )
    {
        $includeCriterion = array();
        if ( !empty( $includeContentTypes ) )
        {
            foreach ( $includeContentTypes as $contentTypeIdentifier )
            {
                $contentType = $this->getRepository()->getContentTypeService()->loadContentTypeByIdentifier( $contentTypeIdentifier );
                $includeCriterion[] = new Criterion\ContentTypeId( $contentType->id);
            }
        }
        $criteria = array(
            new Criterion\ParentLocationId( $locationId ),
            new Criterion\Visibility( Criterion\Visibility::VISIBLE )
        );

        if ( !empty( $includeCriterion ) )
            $criteria[] = new Criterion\LogicalAnd( $includeCriterion );

        $query = new Query(
            array(
                'criterion' => new Criterion\LogicalAnd(
                    $criteria
                ),
                'sortClauses' => array(
                    new SortClause\LocationPriority( Query::SORT_ASC )
                )
            )
        );

        $searchResult = $this->getRepository()->getSearchService()->findContent( $query );

        $locationList = array();
        if ( $searchResult instanceof SearchResult )
        {
            foreach ( $searchResult->searchHits as $searchHit )
            {
                $locationList[] = $this->getRepository()->getLocationService()->loadLocation( $searchHit->valueObject->contentInfo->mainLocationId );
            }
        }
        return $locationList;
    }

sub_items.html.twig

{#
    Process a list of children content objects and render them using line template
    
    TODO: select default line view template based on content class
#}

<div class="content-view-children">
    {% for content in contentList %}
        {% include "WebmanufakturSiteDruckformBundle::line.html.twig" %}
    {% endfor %}
</div>