細錯誤消息

Question

當我運行ruby filename.rb ，瘦網絡服務器啟動，但是當我嘗試在localhost：4567上查看（Sinatra）應用程序時，出現此錯誤消息。 谷歌搜索沒有發現任何東西。 有誰知道我會怎么做才能克服這個問題？

gems/eventmachine-0.12.10/lib/em/connection.rb:39:in `block in new': undefined method `associate_callback_target' for #<Thin::Connection:0x00000100fc7500> (NoMethodError)
    from /Users/michaeljohnmitchell/.rvm/gems/ruby-1.9.2-p290@rails3tutorial/gems/eventmachine-0.12.10/lib/em/connection.rb:36:in `instance_eval'
    from /Users/michaeljohnmitchell/.rvm/gems/ruby-1.9.2-p290@rails3tutorial/gems/eventmachine-0.12.10/lib/em/connection.rb:36:in `new'
    from /Users/michaeljohnmitchell/.rvm/gems/ruby-1.9.2-p290@rails3tutorial/gems/eventmachine-0.12.10/lib/eventmachine.rb:1430:in `event_callback'
    from /Users/michaeljohnmitchell/.rvm/gems/ruby-1.9.2-p290@rails3tutorial/gems/eventmachine-0.12.10/lib/pr_eventmachine.rb:815:in `block in eventable_read'
    from /Users/michaeljohnmitchell/.rvm/gems/ruby-1.9.2-p290@rails3tutorial/gems/eventmachine-0.12.10/lib/pr_eventmachine.rb:812:in `times'
    from /Users/michaeljohnmitchell/.rvm/gems/ruby-1.9.2-p290@rails3tutorial/gems/eventmachine-0.12.10/lib/pr_eventmachine.rb:812:in `eventable_read'
    from /Users/michaeljohnmitchell/.rvm/gems/ruby-1.9.2-p290@rails3tutorial/gems/eventmachine-0.12.10/lib/pr_eventmachine.rb:369:in `block in crank_selectables'
    from /Users/michaeljohnmitchell/.rvm/gems/ruby-1.9.2-p290@rails3tutorial/gems/eventmachine-0.12.10/lib/pr_eventmachine.rb:369:in `each'
    from /Users/michaeljohnmitchell/.rvm/gems/ruby-1.9.2-p290@rails3tutorial/gems/eventmachine-0.12.10/lib/pr_eventmachine.rb:369:in `crank_selectables'
    from /Users/michaeljohnmitchell/.rvm/gems/ruby-1.9.2-p290@rails3tutorial/gems/eventmachine-0.12.10/lib/pr_eventmachine.rb:324:in `block in run'
    from /Users/michaeljohnmitchell/.rvm/gems/ruby-1.9.2-p290@rails3tutorial/gems/eventmachine-0.12.10/lib/pr_eventmachine.rb:318:in `loop'
    from /Users/michaeljohnmitchell/.rvm/gems/ruby-1.9.2-p290@rails3tutorial/gems/eventmachine-0.12.10/lib/pr_eventmachine.rb:318:in `run'
    from /Users/michaeljohnmitchell/.rvm/gems/ruby-1.9.2-p290@rails3tutorial/gems/eventmachine-0.12.10/lib/pr_eventmachine.rb:64:in `run_machine'
    from /Users/michaeljohnmitchell/.rvm/gems/ruby-1.9.2-p290@rails3tutorial/gems/eventmachine-0.12.10/lib/eventmachine.rb:256:in `run'
    from /Users/michaeljohnmitchell/.rvm/gems/ruby-1.9.2-p290@rails3tutorial/gems/thin-1.4.1/lib/thin/backends/base.rb:63:in `start'
    from /Users/michaeljohnmitchell/.rvm/gems/ruby-1.9.2-p290@rails3tutorial/gems/thin-1.4.1/lib/thin/server.rb:159:in `start'
    from /Users/mm/.rvm/gems/ruby-1.9.2-p290@rails3tutorial/gems/rack-1.4.1/lib/rack/handler/thin.rb:13:in `run'
    from /Users/mm/.rvm/gems/ruby-1.9.2-p290@rails3tutorial/gems/sinatra-1.3.3/lib/sinatra/base.rb:1350:in `run!'
    from /Users/mm/.rvm/gems/ruby-1.9.2-p290@rails3tutorial/gems/sinatra-1.3.3/lib/sinatra/main.rb:25:in `block in <module:Sinatra>'

該代碼來自《用Ruby克隆Internet應用程序》一書。 它的每個演示應用程序都在發生...

路線代碼

get '/' do haml :index end

post '/' do
  uri = URI::parse(params[:original])
  custom = params[:custom].empty? ? nil : params[:custom]
  raise "Invalid URL" unless uri.kind_of? URI::HTTP or uri.kind_of? URI::HTTPS
  @link = Link.shorten(params[:original], custom) 
  haml :index
end

['/info/:short_url', '/info/:short_url/:num_of_days', '/info/:short_url/:num_of_days/:map'].each do |path|
  get path do
    @link = Link.first(:identifier => params[:short_url])
    raise 'This link is not defined yet' unless @link
    @num_of_days = (params[:num_of_days] || 15).to_i
    @count_days_bar = Visit.count_days_bar(params[:short_url], @num_of_days)
    chart = Visit.count_country_chart(params[:short_url], params[:map] || 'world')
    @count_country_map = chart[:map]
    @count_country_bar = chart[:bar]
    haml :info
  end
end

get '/:short_url' do 
  link = Link.first(:identifier => params[:short_url])
  link.visits << Visit.create(:ip => get_remote_ip(env))
  link.save
  redirect link.url.original, 301
end

error do haml :index end

def get_remote_ip(env)
  if addr = env['HTTP_X_FORWARDED_FOR']
    addr.split(',').first.strip
  else
    env['REMOTE_ADDR']
  end
end

Answer 1

我是《 用Ruby克隆Internet應用程序》一書的作者。 我嘗試在GitHub存儲庫中運行代碼，並且由於進行了一些更改（由於Sinatra的更改），我可以成功運行它。 也許您可以嘗試Prakash Murthy給出的答案，以升級到EventMachine 1.0.0，但是我正在運行與您相同的版本（0.12.10），這不會給我帶來任何問題。

如果您直接給我發送電子郵件，我們可以解決（並稍后更新Stack Overflow）。

Answer 2

我在使用Ruby 1.9.2時遇到了這個問題。 兩個版本的Eventmachine（0.12.10和1.0.x）都出現了此問題。 遵循鏈接的Github問題中的技巧之后，我切換到Ruby 2.1.1並重新打包。 安裝了Eventmachine 1.0.3，問題消失了。

（這整個過程涉及到我很多ving牛工作，涉及到將Mac更新到Mavericks，吹走許多廢棄的庫以及重新安裝Xcode和Homebrew-希望對其他人來說更簡單。）