How to set content length by send_file

问题

I don't know how to set content-length by send_file.

I checked the api, there's no content-length param.

回答1:

You can set headers for response like:

def download
  @file = Attachment.find params[:id]

  response.headers['Content-Length'] = @file.size.to_s
  send_file @file.path, :x_sendfile => true
end

More info about response object you can find on official docs.

P.S: The Header needs to be a string to work properly with some webservers.

来源：https://stackoverflow.com/questions/29485042/how-to-set-content-length-by-send-file