Attachment_fu, Watermarks and after_save

Rails
1

Hi,
I’m having an issue with trying to watermark an uploaded image using
attachment_fu and Rails 2.0.2.

The model looks like…

class Picture < ActiveRecord::Base
belongs_to :gallery
after_save :watermark_image

has_attachment :content_type => :image,
:storage => :file_system,
:max_size => 2.megabytes,
:resize_to => ‘500x500’,
:processor => “Rmagick”,
:thumbnails => {
:large => ‘128x128>’,
:small => ‘64x64>’
}
validates_as_attachment

def watermark_image
dst = Magick::Image.read("#{RAILS_ROOT}/
public#{self.public_filename}").first
src = Magick::Image.read("#{RAILS_ROOT}/config/Logo.png").first
result = dst.composite(src, Magick::SouthEastGravity,
Magick::OverCompositeOp)
result.write("#{RAILS_ROOT}/public#{self.public_filename}")
end
end

The code fails with a ‘Cannot read image’ on the ‘dst = …’ line of
the watermark_image method.

Looks like the file does not actually exist in the file system until
after ‘after_save’?

removing the ‘after_save’ and all works, except of course no
watermark…

Anyone have an ideas on how to achieve this?

thanks in advance…

2

kevin evans wrote:

Hi,

Anyone have an ideas on how to achieve this?

thanks in advance…

Besides public_filename there are other methods within the
Attachment_fu’ modified model that you can get at… I don’t remember off
the top of my head what it’s name is but you can do the following to
find out

script/console

Picture.instance_methods.grep /path/

One of those methods should get you an absolute path in which your
after_save filter should work…

I haven’t done this myself (other than using the alternate path methods)
and it’s only the path I would take myself…

hth

ilan

3

I have the exact same code as you do, and it works pefectly.

Actually, I also have ‘unless self.thumbnail?’ at the beginning of
that code block because I was getting my fullsize logo on top of my
thumbnails as well, but that’s a different story.

I would check your paths to make sure that things are where you expect
them. ‘after save’ is, well, after the record/file is saved, so I
would look elsewhere for your problem. When you’re looking at the
error page, are you 1000% sure that the path shown for the error page
exists and is valid?