Hi,

When I attempt to add a new file with an unknown/new extension (say *.xyz) upon completing the upload in the CMS, I get a "Forbidden" error in UploadField. (I've already allowed this extension in UploadField - $myUploadField->getValidator()->setAllowedExtensions(array('xyz'));

Interestingly, the file is uploaded despite the error and when I try to attach the file to my DataaObject (via "From Files", as it is already now in the Assets folder) I can successfully attach the file.

After a bit of digging around, I can see that I have to add the new file extension via

File::$allowed_extensions[] = 'xyz'; 

However, this array is private and so I get a Fatal error: Cannot access private property File::$allowed_extensions.

So how would I be able add a new file type without hacking the core?

I don't want the file to be served so I won't add it in assets/.htaccess - just want to be able to upload it and use it within the web app.

Thanks,
VWD

You need to use the config API to add it. Something like this in config.yml will do it:

File:
   allowed_extensions:
    - xyz