ActionController::DataStreaming#send_file and ActionController::DataStreaming#send_data should not require the :disposition => option.
The reason is that the Content-Disposition HTTP response header is optional. There are many cases where we might want to deliver bytes in the response using the convenience of #send_file or #send_data, but where the Content-Disposition header is not useful. One example would be HTML pages that are pre-generated and stored in a database or distributed filesystem, and where we would like to send them down to the browser from the database (with #send_data) or from the filesystem (with #send_file)
I also thinks that it should be optional.
@josevalim What do you think?
Given it's considered optional, seems to make sense to not require it by default.
@yfeldblum perhaps you could work on a patch for this? That'd be great :)
allow send_file/send_data to skip disposition header, closes #2973