Question

I am having issues with twig escaping output on method calls to an object passed into my twig template. I know I can get around this with the |raw filter, but was hoping there might be a way I could simply specify in my object that certain methods are safe and therefore remove the need for the raw filter.

Answer 1

Method calls of objects itself cannot be made html safe because normal objects/entities are not (and should not be) aware of the template engine.

However, a twig filter or function if aware of the template engine and can be marked html safe in its definition.

So what you need to do is to implement a html safe twig filter to pass the object to and call the method of your object inside the filter function.

I guess your templates looks like this:

<p>{{myObj.getHtmlRepresentation()|raw}}</p>

Now you need to implement a twig filter and change the template to the following:

<p>{{myObj|html_representation}}</p>

And the twig extension should look like this:

class MyTwigExtension {

    public function getFilters(){
       return array(
        // the magic is the is_safe=>html option
        'html_representation' => new \Twig_Filter_Method($this,'htmlRepresentation',array('is_safe'=>array('html'))),
    }

    public function htmlRepresentation($obj){
        return $obj->getHtmlRepresentation();
    }

 }

One design consideration: If your object is an entity of a business object of some kind, it sould not create html but you should move the html creation to a template or the twig filter..