responds to mp3

To allow a client to download an MP3 file from Rails:

First, download the mime-types gem:

gem install mime-types

Then, register mp3 as a Mime type in environment.rb:

Mime::Type.register 'audio/mpeg', :mp3

Then in your "respond_to" block, add a handler for mp3 files. Redirect the user to the location of the file you want to download.

  def show_recording_audio_file
    @recording = Recording.find(params[:id])
    @audio_file = @recording.audio_file
    respond_to do |format|
      format.html # index.html.erb
      format.mp3 {
          redirect_to @audio_file.public_filename
      }
      format.xml  { render :xml => @audio_file }
    end
  end

You could also send the file directly:

send_file RAILS_ROOT + "/public" @audio_file.public_filename + ".mp3"