Setting the mime-type for files stored in the private directory

Question

How do I set the mime-type of files being served from the drupal private directory. I have a webm file in the private directory, and the I've added the <video> tag to the page using a tpl file.

I've tried adding

AddType video/webm .webm

to .htaccess. I've also tried installing the module "File Mime" to try to set the right mime type. I've tried adding

function mymodule_file_download($uri){
    return array('Content-type: '.'video/webm');
}

to my .module file. Nothing seems to work. Any help would be appreciated.

Answer 1

Editing includes/files.mimetypes.inc is a core hack, which you should strive to avoid.

Instead, use hook_file_mimetype_mapping_alter():

function mymodule_file_mimetype_mapping_alter(&$mapping) {
  // Add new MIME type 'video/webm'.
  $mapping['mimetypes']['webm'] = 'video/webm';
  // Add new extension '.webm' and map it to the 'video/webm' MIME type.
  $mapping['extensions']['webm'] = 'webm';
}

Answer 2

Figured this out myself: I had to add the webm mimetype in the appropriate places in the includes/files.mimetypes.inc file to get drupal to serve private files with the correct mimetype.