Random File Name

[Florian]

Hi!

First of all i would like to thank everybody involved for this
wonderful plugin!

In order to prevent users or bots to iterate over the uploaded images,
i would
like to name each image after a random key. e.g.
"jfrh8f3hr8f34fr939e929ke329rj49r.jpg"
I know that i can configure paperclip to rename images automatically
after upload,
but the renaming scheme seems to be static. Does anyone have an idea
how i could
assign a different random key for each uploaded image?

Thanks a lot!

Florian

[Jonathan Yurek]

Hi,

If you're generating and saving the random name of the file in the
database you can add your own interpolation which can be used in urls
and paths.

Paperclip::Attachment.interpolations[:random_key] = lambda do |
attachment, style|
attachment.instance.random_key
end

:path => ":attachment/:style/:random_key.:extension"

... for example.

Hope that helps.

--
Jonathan Yurek, Founder and CTO
thoughtbot, inc.
organic brains. digital solutions.

617.482.1300 x114
http://www.thoughtbot.com/

[Florian]

Hi Jonathan!

works like a charm. That was exactly the hint i needed!
Keep up the good work!

Florian

[Trevor Turk]

On Dec 18 2008, 5:15 pm, Jonathan Yurek <jyu...@thoughtbot.com> wrote:
> If you're generating and saving therandomname of the file in the  

> database you can add your own interpolation which can be used in urls  
> and paths.

I'd been doing this with a before_create callback instead:

class Photo < ActiveRecord::Base
has_attached_file :image # ...

before_create :randomize_file_name

def randomize_file_name
extension = self.image_file_name.scan(/\.\w+$/).to_s.downcase
self.image_file_name = "#{CGI::Session.generate_unique_id}#
{extension}"
end
end

Not sure if this is better than the interpolation method, but it seems
to work well enough. Let me know if this stands out as a bad
technique, though!

- Trevor