title: How to add custom metadata to the 404 response from a Google Cloud Storage bucket?
body: <p>Google Cloud Storage provides an option to configure a 404 HTML page to serve when a request is made for a non-existent object.</p>
  
  <p>Relevant Google docs - <a href="https://cloud.google.com/storage/docs/gsutil/commands/web" rel="nofollow noreferrer">https://cloud.google.com/storage/docs/gsutil/commands/web</a></p>
  
  <p>Is there any way I can attach custom response headers on this plain 404 response?</p>
  
  <p>My intent is to figure out what URL/object key resulted in the 404 response.</p>