uninitialized constant Paperclip::Cropper

Question

I have a custom processor for my Paperclip styles: cropper.rb. Though it is not called and return NameError (uninitialized constant Paperclip::Cropper) error.

It has been discussed here : Rails3 and Paperclip but a while ago. It was concerning Rails 3 back then.

I am under Rails 5 (update from Rails 4.x)

Profilepic.rb

class Profilepic < ApplicationRecord

  belongs_to :professionnels

  has_attached_file :image, styles: { big: "1200x1200", medium: "400x400", small: "250x250"}
  validates_attachment :image, content_type: { content_type: ["image/jpeg", "image/gif", "image/png"] }, size: {less_than: 10.megabytes}

  has_attached_file :finalimage, styles: { medium: "500x500", small: "200x200"}, whiny: false, use_timestamp: false, processors: [:cropper]

  attr_accessor :crop_x, :crop_y, :crop_w, :crop_h

end

lib/paperclip_processors/cropper.rb

module Paperclip
  class CustomCropper < Thumbnail
    def initialize(file, options = {}, attachment = nil)
      super
      if target.crop_w && target.crop_x
        @current_geometry.width  = target.crop_w
        @current_geometry.height = target.crop_h
      end
    end

    def target
      @attachment.instance
    end

    def transformation_command
      # call crop processing only if user inputs are there
      if target.crop_w && target.crop_x
        crop_command = [
            "-crop",
            "#{target.crop_w}x" \
            "#{target.crop_h}+" \
            "#{target.crop_x}+" \
            "#{target.crop_y}",
            "+repage"
        ]
        crop_command + super
      else
        super
      end
    end

  end
end

Answer 1

OK花了一天时间才意识到正确的lib子文件夹实际上是paperclip而不是paperclip_processors尽管Paperclip Git确实提到了有效和自动加载。