How to render Twig template from database in symfony2

Question

I\'m working on application written in symfony2 and I want to send email after some action/event... the problem is, that the users can define something like \"email template

Answer 1

I recently had to implement a CMS used by multiple parties where each party could completely customize their templates. To achieve this I implemented a custom Twig Loader.

The most difficult part was coming up with a naming convention for the templates guaranteed not to overlap with any existing templates, for example !AppBundle:template.html.twig. In case the template was not customised, the template AppBundle:template.html.twig would have to be loaded as fallback template.

However, this is not possible with the Chain Loader (AFAIK) because there the template name cannot be modified. Therefore I had to inject the default loader (i.e. the loader chain) into my loader and use it to load the fallback template.

Another solution would be to pass the request stack or the session to the template loader, making it possible to automatically detect the organisation, but this is difficult because the security component depends on the templating subsystem, causing circular dependency issues.