无法使用 sidekiq 为关注点定义多个“包含”块

Question

如果我正在运行 sidekiq，我会遇到以下异常：

可以看出，尽管我在我的应用程序中没有使用 require 或 require_relative，但由于某种奇怪的原因，需要两次 date_at_relative_to_now 类。我完全依赖rails自动加载功能。

感谢任何想法或帮助

→ sidekiq
loading...
loading...
Cannot define multiple 'included' blocks for a Concern
/Users/boti/.rvm/gems/ruby-2.2.0@checker/gems/activesupport-4.2.0/lib/active_support/concern.rb:126:in `included'
/Users/boti/Rails/checker/app/exhibits/concerns/date_at_relative_to_now.rb:6:in `<module:DateAtRelativeToNow>'
/Users/boti/Rails/checker/app/exhibits/concerns/date_at_relative_to_now.rb:3:in `<top (required)>'
/Users/boti/.rvm/gems/ruby-2.2.0@checker/gems/activesupport-4.2.0/lib/active_support/dependencies.rb:457:in `load'
/Users/boti/.rvm/gems/ruby-2.2.0@checker/gems/activesupport-4.2.0/lib/active_support/dependencies.rb:457:in `block in load_file'
/Users/boti/.rvm/gems/ruby-2.2.0@checker/gems/activesupport-4.2.0/lib/active_support/dependencies.rb:647:in `new_constants_in'
/Users/boti/.rvm/gems/ruby-2.2.0@checker/gems/activesupport-4.2.0/lib/active_support/dependencies.rb:456:in `load_file'
/Users/boti/.rvm/gems/ruby-2.2.0@checker/gems/activesupport-4.2.0/lib/active_support/dependencies.rb:354:in `require_or_load'
/Users/boti/.rvm/gems/ruby-2.2.0@checker/gems/activesupport-4.2.0/lib/active_support/dependencies.rb:317:in `depend_on'
/Users/boti/.rvm/gems/ruby-2.2.0@checker/gems/activesupport-4.2.0/lib/active_support/dependencies.rb:233:in `require_dependency'
/Users/boti/.rvm/gems/ruby-2.2.0@checker/gems/railties-4.2.0/lib/rails/engine.rb:472:in `block (2 levels) in eager_load!'
/Users/boti/.rvm/gems/ruby-2.2.0@checker/gems/railties-4.2.0/lib/rails/engine.rb:471:in `each'
/Users/boti/.rvm/gems/ruby-2.2.0@checker/gems/railties-4.2.0/lib/rails/engine.rb:471:in `block in eager_load!'
/Users/boti/.rvm/gems/ruby-2.2.0@checker/gems/railties-4.2.0/lib/rails/engine.rb:469:in `each'
/Users/boti/.rvm/gems/ruby-2.2.0@checker/gems/railties-4.2.0/lib/rails/engine.rb:469:in `eager_load!'
/Users/boti/.rvm/gems/ruby-2.2.0@checker/gems/railties-4.2.0/lib/rails/engine.rb:346:in `eager_load!'
/Users/boti/.rvm/gems/ruby-2.2.0@checker/gems/railties-4.2.0/lib/rails/application/finisher.rb:56:in `each'
/Users/boti/.rvm/gems/ruby-2.2.0@checker/gems/railties-4.2.0/lib/rails/application/finisher.rb:56:in `block in <module:Finisher>'
/Users/boti/.rvm/gems/ruby-2.2.0@checker/gems/railties-4.2.0/lib/rails/initializable.rb:30:in `instance_exec'
/Users/boti/.rvm/gems/ruby-2.2.0@checker/gems/railties-4.2.0/lib/rails/initializable.rb:30:in `run'
/Users/boti/.rvm/gems/ruby-2.2.0@checker/gems/railties-4.2.0/lib/rails/initializable.rb:55:in `block in run_initializers'
/Users/boti/.rvm/rubies/ruby-2.2.0/lib/ruby/2.2.0/tsort.rb:226:in `block in tsort_each'
/Users/boti/.rvm/rubies/ruby-2.2.0/lib/ruby/2.2.0/tsort.rb:348:in `block (2 levels) in each_strongly_connected_component'
/Users/boti/.rvm/rubies/ruby-2.2.0/lib/ruby/2.2.0/tsort.rb:429:in `each_strongly_connected_component_from'
/Users/boti/.rvm/rubies/ruby-2.2.0/lib/ruby/2.2.0/tsort.rb:347:in `block in each_strongly_connected_component'
/Users/boti/.rvm/rubies/ruby-2.2.0/lib/ruby/2.2.0/tsort.rb:345:in `each'
/Users/boti/.rvm/rubies/ruby-2.2.0/lib/ruby/2.2.0/tsort.rb:345:in `call'
/Users/boti/.rvm/rubies/ruby-2.2.0/lib/ruby/2.2.0/tsort.rb:345:in `each_strongly_connected_component'
/Users/boti/.rvm/rubies/ruby-2.2.0/lib/ruby/2.2.0/tsort.rb:224:in `tsort_each'
/Users/boti/.rvm/rubies/ruby-2.2.0/lib/ruby/2.2.0/tsort.rb:203:in `tsort_each'
/Users/boti/.rvm/gems/ruby-2.2.0@checker/gems/railties-4.2.0/lib/rails/initializable.rb:54:in `run_initializers'
/Users/boti/.rvm/gems/ruby-2.2.0@checker/gems/railties-4.2.0/lib/rails/application.rb:352:in `initialize!'
/Users/boti/Rails/checker/config/environment.rb:5:in `<top (required)>'
/Users/boti/.rvm/gems/ruby-2.2.0@checker/gems/activesupport-4.2.0/lib/active_support/dependencies.rb:274:in `require'
/Users/boti/.rvm/gems/ruby-2.2.0@checker/gems/activesupport-4.2.0/lib/active_support/dependencies.rb:274:in `block in require'
/Users/boti/.rvm/gems/ruby-2.2.0@checker/gems/activesupport-4.2.0/lib/active_support/dependencies.rb:240:in `load_dependency'
/Users/boti/.rvm/gems/ruby-2.2.0@checker/gems/activesupport-4.2.0/lib/active_support/dependencies.rb:274:in `require'
/Users/boti/.rvm/gems/ruby-2.2.0@checker/gems/sidekiq-3.3.4/lib/sidekiq/cli.rb:241:in `boot_system'
/Users/boti/.rvm/gems/ruby-2.2.0@checker/gems/sidekiq-3.3.4/lib/sidekiq/cli.rb:50:in `run'
/Users/boti/.rvm/gems/ruby-2.2.0@checker/gems/sidekiq-3.3.4/bin/sidekiq:8:in `<top (required)>'
/Users/boti/.rvm/gems/ruby-2.2.0@checker/bin/sidekiq:23:in `load'
/Users/boti/.rvm/gems/ruby-2.2.0@checker/bin/sidekiq:23:in `<main>'
/Users/boti/.rvm/gems/ruby-2.2.0@checker/bin/ruby_executable_hooks:15:in `eval'
/Users/boti/.rvm/gems/ruby-2.2.0@checker/bin/ruby_executable_hooks:15:in `<main>'
ruby-2.2.0@checker:boti:~/Rails/checker git:active_job_exercise 
→ 

date_at_relative_to_now.rb 的代码：

module DateAtRelativeToNow
  puts 'loading...'
  extend ActiveSupport::Concern

  included do
    include ActionView::Helpers::DateHelper
  end

  module ClassMethods
    attr_reader :field

    def applicable_to?(object, _context)
      field = self.field
      object.respond_to? field
    end

    def applicable_to(field)
      @field = field

      define_method field do
        date = __getobj__.send self.__class__.field
        if date.present?
          "#{distance_of_time_in_words_to_now date} ago"
        else
          'Never'
        end
      end
    end
  end
end

Answer 1

activesupport 不支持包含在“包含”块中的问题。

从 DateAtRelativeToNow 中删除 include ActionView::Helpers::DateHelper 行，并将其包含在您需要的模块或类中。

Answer 2

activesupport 'included' 功能的实现：

        def included(base = nil, &block)
          if base.nil?
            raise MultipleIncludedBlocks if instance_variable_defined?(:@_included_block)

            @_included_block = block
          else
            super
          end
        end