Passing a parameter to the uploader / accessing a model's attribute from within the uploader / letting the user pick the thumbnail size

I would like to crop an image to the size the user has selected from a list (e.g. 100x100px, 200x200px,...) How would I pass that attribute to the uploader or get the model's attribute from within the uploader?

Accessing the model's attribute from within the uploader as following does not work:

version :thumb do thumbnail_size = model.thumbnail_size ... ... end

I get following error:

undefined local variable or method `model' for #

Thank you! Florian

-------------Problems Reply------------

In order to be able to access the model's attribute I had to add a manipulation helper.

class MyUploader < CarrierWave::Uploader::Base

version :thumb do
process :custom_thumbnail
process :convert => 'jpg'

def custom_thumbnail
width = model.get_image_width
height = model.get_image_height

manipulate! do |img|
img.convert "#{width}x#{height}"

Category:ruby on rails 3 Views:9 Time:2011-10-10

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