How to link to captured audio file?

Hi I’m just getting into Rails and have come across a problem I can’t
find
a solution for.

Basically, answers is a sub resource of questions and you can record an
answer using HTML5’s getUserMedia.

The recording is posting fine in the create action, but how can I get it
again for the show action?

The answer controller includes:

def save_file
audio = params[:audio]
save_path = Rails.root.join(“public/#{audio.original_filename}”)
audio.rewind
File.open(save_path, ‘wb’) do |f|
f.write audio.read
end
end

The show view includes:

Play answer

type="audio/wav">

Could anyone please hint at what I need to insert into ???