How to Work with Different Output Formats in TemplatesΒΆ
Templates are a generic way to render content in any format. While in most cases you'll use templates to render HTML content, a template can just generate JavaScript, CSS, XML or any other format.
For example, the same "resource" is often rendered in several formats. To render an article index page in XML, include the format in the template name:
- XML template name:
article/show.xml.twig
- XML template filename:
show.xml.twig
In reality, this is nothing more than a naming convention and the template isn't actually rendered differently based on its format.
In many cases, you may want to allow a single controller to render multiple different formats based on the "request format". For that reason, a common pattern is to do the following:
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 | // ...
use Symfony\Component\Routing\Annotation\Route;
class ArticleController extends AbstractController
{
/**
* @Route("/{slug}")
*/
public function show(Request $request, $slug)
{
// retrieve the article based on $slug
$article = ...;
$format = $request->getRequestFormat();
return $this->render('article/show.'.$format.'.twig', [
'article' => $article,
]);
}
}
|
The getRequestFormat()
on the Request
object defaults to html
,
but can return any other format based on the format requested by the user.
The request format is most often managed by the routing, where a route can
be configured so that /about-us
sets the request format to html
while
/about-us.xml
sets the format to xml
. This can be achieved by using the
special _format parameter in your route definition:
1 2 3 4 5 6 7 | /**
* @Route("/{slug}.{_format}", defaults={"_format"="html"}, requirements={"_format"="html|xml"}))
*/
public function show(Request $request, $slug)
{
// ...
}
|
Now, include the _format
placeholder when generating a route for another
format:
1 2 3 | <a href="{{ path('article_show', {'slug': 'about-us', '_format': 'xml'}) }}">
View as XML
</a>
|
Tip
When building APIs, using file name extensions often isn't the best solution. The FOSRestBundle provides a request listener that uses content negotiation. For more information, check out the bundle's Request Format Listener documentation.