在Rails 3中使用回形针裁剪照片时出现错误

Question

嗨，我正在尝试使用回形针和imagemagick裁剪照片。我在裁剪照片时遇到了一些错误。以下是错误堆栈：

?[32mCommand?[0m :: convert "C:/Users/Anand/AppData/Local/Temp/120120924-3568-tx
2bxy.jpg[0]" -crop 103x103+0+0 -auto-orient "C:/Users/Anand/AppData/Local/Temp/1
20120924-3568-tx2bxy20120924-3568-16dij9c"
?[32mCommand?[0m :: file -b --mime "C:/Users/Anand/AppData/Local/Temp/120120924-
3568-tx2bxy20120924-3568-16dij9c"
[paperclip] Error while determining content type: Cocaine::CommandNotFoundError
?[32mCommand?[0m :: identify -format %wx%h "C:/Users/Anand/AppData/Local/Temp/12
0120924-3568-tx2bxy.jpg[0]"
  ?[1m?[36m (0.0ms)?[0m  ?[1mrollback transaction?[0m
Completed 500 Internal Server Error in 145552ms

NoMethodError (undefined method `exitstatus' for nil:NilClass):
  app/models/user.rb:14:in `reprocess_photo'
  app/models/user.rb:14:in `reprocess_photo'
  app/models/user.rb:14:in `reprocess_photo'
  app/models/user.rb:14:in `reprocess_photo'
  app/models/user.rb:14:in `reprocess_photo'
  app/models/user.rb:14:in `reprocess_photo'
  app/models/user.rb:14:in `reprocess_photo'
  app/controllers/users_controller.rb:67:in `block in update'
  app/controllers/users_controller.rb:66:in `update'


  Rendered E:/Ruby192/lib/ruby/gems/1.9.1/gems/actionpack-3.2.8/lib/action_dispa
tch/middleware/templates/rescues/_trace.erb (10.0ms)
  Rendered E:/Ruby192/lib/ruby/gems/1.9.1/gems/actionpack-3.2.8/lib/action_dispa
tch/middleware/templates/rescues/_request_and_response.erb (1.0ms)
  Rendered E:/Ruby192/lib/ruby/gems/1.9.1/gems/actionpack-3.2.8/lib/action_dispa
tch/middleware/templates/rescues/diagnostics.erb within rescues/layout (51.0ms)
Exiting

model/user.rb文件：

class User < ActiveRecord::Base
  attr_accessible :name,:photo,:crop_x,:crop_y,:crop_w,:crop_h
  has_attached_file :photo,:styles => {:small=>"100x100#",:large=>"500x500>"},:processors => [:cropper]
  attr_accessor :crop_x,:crop_y,:crop_w,:crop_h
  after_update :reprocess_photo,:if=>:cropping?

  def cropping?
    !crop_x.blank? && !crop_y.blank? && !crop_w.blank? && !crop_h.blank?
  end

  private 

  def reprocess_photo
    photo.reprocess!
  end

end

我的lib/paperclip_processros/cropper.rb

module Paperclip
  class Cropper < Thumbnail
    def transformation_command
      if crop_command   
        #this generates command :
        #this is right #convert "C:/Users/Anand/AppData/Local/Temp/1.jpg[0]" -crop 102x102+0+0 -auto-orient "C:/Users/Anand/AppData/Local/Temp/120120924-2336-qbzroo20120924-2336-1jqbiiv.jpg"
        crop_command + super.first.sub(/ -crop \S+/, '')
      else
        super
      end
    end

    def crop_command
      target = @attachment.instance
      if target.cropping?
        " -crop #{target.crop_w}x#{target.crop_h}+#{target.crop_x}+#{target.crop_y} "
      end
    end
  end
end

我的配置/env./dev.rb

 Paperclip.options[:swallow_stderr] = false
 Paperclip.options[:command_path] = "C:/Program Files/ImageMagick-6.7.9-Q16/"

当我在裁剪之后更新一张照片时，它会循环。解决方案是什么？

Answer 1

我很确定你遇到了我最初遇到的同样的问题，因此重新处理！方法保存ActiveRecord父级，然后触发after_update回调，这会导致reprocess_photo方法再次被调用。最终结果是一个有点递归的循环，直到你的机器耗尽了可分配的内存，它才会停止。

解决这个问题的简单方法是添加一个名为processing的布尔值属性，它允许您确定我们是否已经在重新处理图像。

attr_accessor :processing

然后，如果图像已经在处理中，则更改reprocess_photo以返回。

  def reprocess_photo
    # don't crop if the user isn't updating the photo
    #   ...or if the photo is already being processed
    return unless (cropping? && !processing)
    self.processing = true
    photo.reprocess!
    self.processing = false
  end

Answer 2

试着改变

 Paperclip.options[:command_path] = "C:/Program Files/ImageMagick-6.7.9-Q16/"

至

  Paperclip.options[:command_path] = 'C:/PROGRA~1/IMAGEM~1.0-Q'

似乎没有找到图像-Magick