Attachment_fu questions

Rails
1

I am having a hard time saving the uploaded files to the directory of
my choice.

There is the method full_filename() that is said to be the one to
override to specify a custom path, but when I do so the file is not
saved

#Here is the original method in the file_system_backend.rb file

# Overwrite this method in your model to customize the filename.
        # The optional thumbnail argument will output the thumbnail's
filename.
        def full_filename(thumbnail = nil)
          file_system_path = (thumbnail ? thumbnail_class :
self).attachment_options[:path_prefix].to_s
          File.join(RAILS_ROOT, file_system_path,
*partitioned_path(thumbnail_name_for(thumbnail)))
        end

I created a custom full_filename method in my Picture class, which was
called on to generate the file name for the uploaded file, but when
this method was used the file was not saved in the directory that I
specified.

Here is the updated method within the Picture class

def full_filename(thumbnail = nil)
    file_system_path = (thumbnail ? thumbnail_class :
self).attachment_options[:path_prefix].to_s
    File.join(RAILS_ROOT, "pictures", thumbnail_name_for(thumbnail))
  end

I admit I am a little confused on how this method overrides the the
one in the file_system_backend.rb file (I will have to read up on
this), but for starters I just want to figure out why the files are
not saving.

There is also an issue in the thumbnails not being created. Sometimes
they are created as they should be, then after testing things at a
later time, they are no longer saved.

The last thing that I am wondering about, is what is the common way to
relate the images/files. I would think just to create an additional
foreign key column in the table relating back to the parent table, but
if that is the case I would have to create a couple of methods in the
parent class, in this case Member, to retrieve a list of the
thumbnails. That just seems like to much extra code for ruby, so I am
thinking that there may already be something that is provided that
will do this.

Thanks for the help.

2

On 8/24/07, chris [email protected] wrote:

I am having a hard time saving the uploaded files to the directory of
my choice.

attachment_fu has a :path_prefix => “/path/to/attachments/directory”
option which allows you to set the directory of the uploaded files. I
can’t remember off hand if it allows you to store them in a directory
anywhere on the file system, it may require the directory to be under
/public…

There is also an issue in the thumbnails not being created. Sometimes
they are created as they should be, then after testing things at a
later time, they are no longer saved.

I’ve never had inconsistencies in saving thumbnails… For me they
either save or they don’t…

The last thing that I am wondering about, is what is the common way to
relate the images/files. I would think just to create an additional
foreign key column in the table relating back to the parent table, but
if that is the case I would have to create a couple of methods in the
parent class, in this case Member, to retrieve a list of the
thumbnails. That just seems like to much extra code for ruby, so I am
thinking that there may already be something that is provided that
will do this.

I use single table inheritance with a different class for each image
type, which specifies varying dimensions for each image. A better way
of doing it is to use the polymorphic associations, although the
restriction of doing it this way is that you must specify all the
different image dimensions in one file, so you may get some
superfluous image resizes that you don’t necessarily need (ie if you
need an image size of 64x64 pixels for a Product and an image of
128x128 for an Article, you’ll get both sizes for each object, rather
than a single image for a product and a single one for an Article).

If you’re interested in the polymorphic way, you should definitely
check out this sample application:

http://blog.caboo.se/articles/2007/4/11/sample-rails-application

Adam