paperclip upload from url

有时候我们的程序中需要远程获取并保存图片， 根据url去保存也很简单：

has_attached_file :asset, :styles=> {:thumb => "100x100>"} def asset_from_url(url)   extname =File.extname(url)   basename =File.basename(url, extname)   file = Tempfile.new([basename, extname])   file.binmode   open(URI.parse(url))do |data|     file.write data.read   end   file.rewind   self.asset = file end

使用：

image = Image.new
image.asset_from_url(url)
image.save

其他详情 : http://trevorturk.wordpress.com/2008/12/11/easy-upload-via-url-with-paperclip/