Wordpress 3.5+ upload tool filter

Question

i would like to use the brand new wp's upload tool in a personnal theme options page. I found a lot of tutorials like : wp media uploader in plugins ...and it works very fine. But i'd like to filter the file type the end user can select ( and view ). I found many examples that use this way to filter by 'image' type ( param for wp.media object ) :

library:{ type:'image' }

You can see an example here. It works, when the uploader panel appear you only see pictures BUT :

• How can i filter other file types ( documents, zips, videos... ), i tried to replace 'image' by 'video' or 'document' it doesn't work
• When the end user choose to upload a file he can upload any file type instead of an image

How can i fixed that ? How to set a filter for one or more specific file types ?

Thanks a lot for help.

Answer 1

The library parameter is actually responsible of what you see in the library frame and not what you can upload. It accepts : image,audio,video,file or any other mime type for example to show only pdf's :

library: {
    type: 'application/pdf'
},

Now to actually limit the upload to a file type you need to add a parameter to the uploader and catch that parameter using wp_handle_upload_prefilter filter hook.

To add a parameter use:

file_frame.uploader.uploader.param( 'allowed_Type', 'pdf');

and to filter the file type use

add_filter('wp_handle_upload_prefilter', 'Validate_upload_file_type');
function Validate_upload_file_type($file) {
    if (isset($_POST['allowed_Type']) && !empty($_POST['allowed_Type'])){
        //this allows you to set multiple types seperated by a pipe "|"
        $allowed = explode("|", $_POST['allowed_Type']);

        $ext =  substr(strrchr($file['name'],'.'),1);
        //first check if the user uploaded the right type
        if (!in_array($ext, (array)$allowed)){
            $file['error'] = __("Sorry, you cannot upload this file type for this field.");
            return $file;
        }
        //check if the type is allowed at all by WordPress
        foreach (get_allowed_mime_types() as $key => $value) {
            if (strpos($key, $ext) || $key == $ext)
                return $file;
        }
        $file['error'] = __("Sorry, you cannot upload this file type for this field.");
    }
    return $file;
}

Answer 2

Just a slight modification to Bainternet's answer. I'm using WP 3.7.1 and something must have changed in Media Upload since this line does not seem to work for me:

file_frame.uploader.uploader.param( 'allowed_Type', 'pdf');

The following error is shown in Firebug console when opening the Media Upload:

Uncaught TypeError: Cannot call method 'param' of undefined
(anonymous function)
x.event.dispatch
v.handle

This worked for me instead:

file_frame.uploader.options.uploader['params']['allowed_type'] = 'pdf';