public function testCreateRelation($restContentVersionHref)
{
$content = <<<XML
<?xml version="1.0" encoding="UTF-8"?>
<RelationCreate>
<Destination href="/api/ezp/v2/content/objects/10"/>
</RelationCreate>
XML;
$request = $this->createHttpRequest('POST', "{$restContentVersionHref}/relations", 'RelationCreate+xml', 'Relation+json');
$request->setContent($content);
$response = $this->sendHttpRequest($request);
self::assertHttpResponseCodeEquals($response, 201);
$response = json_decode($response->getContent(), true);
return $response['Relation']['_href'];
}