Rails4: CKEditor gsub error - ruby-on-rails

Question

I have a project in rails 4 that uses ckeditor with cloudinary. The uplaod to Cloudinary works fine, but after the upload, when the editor should lad the image, I get the error:
NoMethodError - undefined method `gsub' for nil:NilClass:
My CKEditor Picture Uploader is:
# encoding: utf-8
class CkeditorPictureUploader < CarrierWave::Uploader::Base
include Ckeditor::Backend::CarrierWave
include Cloudinary::CarrierWave
include CarrierWave::MiniMagick
[:extract_content_type, :set_size, :read_dimensions].each do |method|
define_method :"#{method}_with_cloudinary" do
send(:"#{method}_without_cloudinary") if self.file.is_a?(CarrierWave::SanitizedFile)
{}
end
alias_method_chain method, :cloudinary
end
process :read_dimensions
# Create different versions of your uploaded files:
version :thumb do
process :resize_to_fill => [118, 100]
end
version :content do
process :resize_to_limit => [800, 800]
end
# Add a white list of extensions which are allowed to be uploaded.
# For images you might use something like this:
def extension_white_list
Ckeditor.image_file_types
end
end
When I go to upload and click on "find image on server" the image is there and I can load the image on editor, but not when I upload image to server
Someone got this problem before?
Thanks!

Answer 1

This error occurs because gsub could not find url for Uploaded image in ckeditor. You have to create ckeditor asset_response.rb file in your lib/ckeditor folder of your App and put this line of code
def asset_url(relative_url_root)
#ckeditor_assets = Ckeditor::Picture.last.url_content
puts #ckeditor_assets.inspect
#return nil if asset.url_content.nil?
url = #ckeditor_assets #Ckeditor::Utils.escape_single_quotes(asset.url_content)
if URI(url).relative?
"#{relative_url_root}#{url}"
else
url
end
end
put the whole code and replace asset_url method with this.
This is just a hack to include Ckeditor::Picture model.
Put this code for cloudinary in CkeditorPictureUploader file
include Ckeditor::Backend::CarrierWave
include Cloudinary::CarrierWave
process :tags => ["photo_album_sample"]
process :convert => "jpg"
version :thumbnail do
eager
resize_to_fit(200, 200)
cloudinary_transformation :quality => 80
end

Answer 2

From #t-s 's answer, I found that in Ckeditor::AssetResponse#asset_url
method, the asset object is not reloaded, so asset.content_url will always be nil thus caused the error. I fixed it like this:
class Ckeditor::Picture < Ckeditor::Asset
...
def url_content
url(:content) || begin
if persisted?
reload
url(:content)
end
end
end
end
And similarly for Ckeditor::AttachmentFile class if you have it.