带有水印处理器的多个回形针附件

时间:2010-09-28 17:52:46

标签: ruby-on-rails ruby image-processing paperclip nested-attributes

使用回形针上传多个附件并使用水印处理它们时遇到了很多麻烦。

我有2个模特,广告和照片。 广告has_many:照片和照片belongs_to:ad。

更确切地说,在/models/ad.rb中我有:

class Ad < ActiveRecord::Base

  has_many :photos, :dependent => :destroy
  accepts_nested_attributes_for :photos, :allow_destroy => true  
end

我的photo.rb文件如下所示:

class Photo < ActiveRecord::Base

belongs_to :ad

has_attached_file :data,
:styles => {
  :thumb => "100x100#",
  :first => {
    :processors => [:watermark],
    :geometry => '300x250#',
    :watermark_path => ':rails_root/public/images/watermark.png',
    :position => 'SouthEast' },
  :large => {
    :processors => [:watermark],
    :geometry => '640x480#',
    :watermark_path => ':rails_root/public/images/watermark.png',
    :position => 'SouthEast' }
}
end

在我看来,我用它来添加文件字段

<% f.fields_for :photos do |p| %>

  <%= p.label :data, 'Poza:' %> <%= p.file_field :data %>

<% end %>

在我的控制器中,在编辑操作中,我使用4.times {@ad.photos.build}生成文件字段。

如果我不使用水印处理器,如果我使用普通的has_attached_file声明,这一切都可以正常工作,如下所示:

has_attached_file :data,
:styles => {
  :thumb => "100x100#",
  :first => '300x250#',
  :large => '640x480#'
}

但是当我使用水印处理器时,我总是会收到这个错误:

 NoMethodError in PublicController#update_ad

 You have a nil object when you didn't expect it!
 You might have expected an instance of ActiveRecord::Base.
 The error occurred while evaluating nil.[]
  ..............................
 /usr/lib/ruby/gems/1.8/gems/activerecord-2.3.5/lib/active_record/nested_attributes.rb:350:in `assign_nested_attributes_for_collection_association'
 /usr/lib/ruby/gems/1.8/gems/activerecord-2.3.5/lib/active_record/nested_attributes.rb:345:in `each'
 /usr/lib/ruby/gems/1.8/gems/activerecord-2.3.5/lib/active_record/nested_attributes.rb:345:in `assign_nested_attributes_for_collection_association'
 /usr/lib/ruby/gems/1.8/gems/activerecord-2.3.5/lib/active_record/nested_attributes.rb:243:in `photos_attributes='
 /usr/lib/ruby/gems/1.8/gems/activerecord-2.3.5/lib/active_record/base.rb:2746:in `send'
 /usr/lib/ruby/gems/1.8/gems/activerecord-2.3.5/lib/active_record/base.rb:2746:in `attributes='
 /usr/lib/ruby/gems/1.8/gems/activerecord-2.3.5/lib/active_record/base.rb:2742:in `each'
 /usr/lib/ruby/gems/1.8/gems/activerecord-2.3.5/lib/active_record/base.rb:2742:in `attributes='
 /usr/lib/ruby/gems/1.8/gems/activerecord-2.3.5/lib/active_record/base.rb:2628:in `update_attributes'
 /home/alexg/Sites/vandmasina/app/controllers/public_controller.rb:217
 /home/alexg/Sites/vandmasina/app/controllers/public_controller.rb:216:in `update_ad'

据我所知,参数还可以

 Parameters:

 {"commit"=>"Salveaza modificarile",
  "ad"=>{"price"=>"6000",
  "oras"=>"9",
  "photos_attributes"=>{"0"=>{"data"=>#<File:/tmp/RackMultipart20100928-5130-b42noe-0>},
  "1"=>{"data"=>#<File:/tmp/RackMultipart20100928-5130-r0ukcr-0>},
  "2"=>{"data"=>#<File:/tmp/RackMultipart20100928-5130-mb23ei-0>},
  "3"=>{"data"=>#<File:/tmp/RackMultipart20100928-5130-1bpkm3b-0>}},

Watermark处理器/lib/paperclip_processors/watermark.rb看起来像这样:

  module Paperclip
class Watermark < Processor

class InstanceNotGiven < ArgumentError; 
end

def initialize(file, options = {},attachment = nil)
  super
  @file = file
  @current_format = File.extname(@file.path)
  @basename = File.basename(@file.path, @current_format)
  @watermark = ':rails_root/public/images/watermark.png'
  @current_geometry = Geometry.from_file file # This is pretty slow
  @watermark_geometry = watermark_dimensions
end

def watermark_dimensions
  return @watermark_dimensions if @watermark_dimensions
  @watermark_dimensions = Geometry.from_file @watermark
end

def make
  dst = Tempfile.new([@basename, @format].compact.join("."))
  watermark = " \\( #{@watermark} -extract #{@current_geometry.width.to_i}x#{@current_geometry.height.to_i}+#{@watermark_geometry.height.to_i /
                2}+#{@watermark_geometry.width.to_i / 2} \\) "
  command = "-gravity center " + watermark + File.expand_path(@file.path) + " " +File.expand_path(dst.path)

  begin
    success = Paperclip.run("composite", command.gsub(/\s+/, " "))
  rescue PaperclipCommandLineError
    raise PaperclipError, "There was an error processing the watermark for #{@basename}" if @whiny_thumbnails
  end
  dst
end

end
end

我在普通应用程序中尝试过处理器,没有多个附件,而且工作完美。据我所知,它不适用于nested_attributes。

应用程序是rails 2.3.5 with ruby​​ 1.8.7和paperclip 2.3.11

如果你可以提供任何帮助,我会非常感激,因为我一直试图解决这个问题2天:)

3 个答案:

答案 0 :(得分:1)

如果您使用rails 3和paperclip&gt; 2.3.3,试试https://gist.github.com/843418来源。

答案 1 :(得分:0)

从快速浏览一下,看起来watermark_path应该是“#{Rails.root} / ...”,虽然看起来你有很多事情要做。

另外,我没有在form_for中看到您的表单。确保你有{:multipart =&gt;真}

答案 2 :(得分:0)

哦,伙计,那是一个艰难的人!

您的代码中的错误很少,并且没有任何与嵌套模型相关的错误。我的解释是针对Rails 3&amp; Paperclip 2.3.3

a):rails_root的东西不起作用。此插值仅用于url / path而不用于自定义选项。所以你应该用Rails.root.join(“public / images ...”)

替换它

b)您只需忽略:watermark_path选项,并且仅使用硬编码路径(在初始化方法中)。所以你的风格和风格一样无关紧要...... / images / watermark.png。 :rails_root还有东西,所以它无法工作。

c)当你将参数传递给Paperclip.run(“复合”,“foo bar there”)时,它实际上执行了这个命令:

composite 'foo bar there'
你能看到单引号吗?因此,复合命令将您的参数视为一个巨大的参数,并且根本不理解它。如果将它作为数组传递,则每个项都包含在引号中,而不是整个数组。

所以这里是水印处理器的改进版本:

module Paperclip
  class Watermark < Processor

  class InstanceNotGiven < ArgumentError;
  end

  def initialize(file, options = {},attachment = nil)
    super
    @file = file
    @current_format = File.extname(@file.path)
    @basename = File.basename(@file.path, @current_format)
    # PAWIEN: use default value only if option is not specified
    @watermark = options[:watermark_path] || Rails.root.join('public/images/watermark.png')
    @current_geometry = Geometry.from_file file # This is pretty slow
    @watermark_geometry = watermark_dimensions
  end

  def watermark_dimensions
    return @watermark_dimensions if @watermark_dimensions
    @watermark_dimensions = Geometry.from_file @watermark
  end

  def make
    dst = Tempfile.new([@basename, @format].compact.join("."))
    dst.binmode

    begin
      # PAWIEN: change original "stringy" approach to arrayish approach
      # inspired by the thumbnail processor
      options = [
        "-gravity",
        "center",
        "#{@watermark}",
        "-extract",
        "#{@current_geometry.width.to_i}x#{@current_geometry.height.to_i}+#{@watermark_geometry.height.to_i / 2}+#{@watermark_geometry.width.to_i / 2}",
        File.expand_path(@file.path),
        File.expand_path(dst.path)
      ].flatten.compact.join(" ").strip.squeeze(" ")

      success = Paperclip.run("composite", options)
    rescue PaperclipCommandLineError
      raise PaperclipError, "There was an error processing the watermark for #{@basename}" if @whiny_thumbnails
    end
    dst
  end

  end
end

希望能帮到你!

更新:您需要使用github上的最新paperclip gem

gem 'paperclip', '>= 2.3.3', :git => "http://github.com/thoughtbot/paperclip.git"

在这个版本中,#run的格式再次被更改,所以我更新了代码。它真的应该工作,因为我已经创建了测试应用程序,它正在做所谓的。

更新2 :使用工作示例回复:

git://repo.or.cz/paperclip-mass-example.git