In another post, we described how to obtain a file’s public URL using Backendless Console. Even though anyone can obtain a public URL for a file or directory, it is very easy to change the permissions to restrict file download for anonymous (not authenticated) users.
To restrict access:
Security permission changes have an immediate effect. As soon as the permission is denied, loading the file with its public URL will result in the following JSON message sent back to the browser (or the calling client):
{ message: "User has no permissions to specified resource", code: 4000 }