无法加载此类文件 - 运行heroku create --stack cedar时的readline(LoadError)

Question

我正在尝试将我的Rails应用程序部署到Heroku,按照以下说明进行测试:

http://devcenter.heroku.com/articles/rails3#prerequisites

这是我正在尝试运行的命令:

heroku create --stack cedar

我收到此错误消息:

/home/sergio/.rvm/rubies/ruby-1.9.3-p125/lib/ruby/site_ruby/1.9.1/rubygems/custom_require.rb:36:in `require': cannot load such file -- readline (LoadError)
    from /home/sergio/.rvm/rubies/ruby-1.9.3-p125/lib/ruby/site_ruby/1.9.1/rubygems/custom_require.rb:36:in `require'
    from /home/sergio/.rvm/gems/ruby-1.9.3-p125/gems/heroku-2.20.1/lib/heroku/command/run.rb:1:in `<top (required)>'
    from /home/sergio/.rvm/rubies/ruby-1.9.3-p125/lib/ruby/site_ruby/1.9.1/rubygems/custom_require.rb:36:in `require'
    from /home/sergio/.rvm/rubies/ruby-1.9.3-p125/lib/ruby/site_ruby/1.9.1/rubygems/custom_require.rb:36:in `require'
    from /home/sergio/.rvm/gems/ruby-1.9.3-p125/gems/heroku-2.20.1/lib/heroku/command.rb:14:in `block in load'
    from /home/sergio/.rvm/gems/ruby-1.9.3-p125/gems/heroku-2.20.1/lib/heroku/command.rb:13:in `each'
    from /home/sergio/.rvm/gems/ruby-1.9.3-p125/gems/heroku-2.20.1/lib/heroku/command.rb:13:in `load'
    from /home/sergio/.rvm/gems/ruby-1.9.3-p125/gems/heroku-2.20.1/lib/heroku/cli.rb:8:in `start'
    from /home/sergio/.rvm/gems/ruby-1.9.3-p125/gems/heroku-2.20.1/bin/heroku:15:in `<top (required)>'
    from /home/sergio/.rvm/gems/ruby-1.9.3-p125/bin/heroku:19:in `load'
    from /home/sergio/.rvm/gems/ruby-1.9.3-p125/bin/heroku:19:in `<main>'

这是相关文件的内容:

#--
# Copyright 2006 by Chad Fowler, Rich Kilmer, Jim Weirich and others.
# All rights reserved.
# See LICENSE.txt for permissions.
#++

module Kernel

  if defined?(gem_original_require) then
    # Ruby ships with a custom_require, override its require
    remove_method :require
  else
    ##
    # The Kernel#require from before RubyGems was loaded.

    alias gem_original_require require
    private :gem_original_require
  end

  ##
  # When RubyGems is required, Kernel#require is replaced with our own which
  # is capable of loading gems on demand.
  #
  # When you call <tt>require 'x'</tt>, this is what happens:
  # * If the file can be loaded from the existing Ruby loadpath, it
  #   is.
  # * Otherwise, installed gems are searched for a file that matches.
  #   If it's found in gem 'y', that gem is activated (added to the
  #   loadpath).
  #
  # The normal <tt>require</tt> functionality of returning false if
  # that file has already been loaded is preserved.

  def require path
    if Gem.unresolved_deps.empty? then
      gem_original_require path
    else
      spec = Gem::Specification.find { |s|
        s.activated? and s.contains_requirable_file? path
      }

      unless spec then
        found_specs = Gem::Specification.find_in_unresolved path
        unless found_specs.empty? then
          found_specs = [found_specs.last]
        else
          found_specs = Gem::Specification.find_in_unresolved_tree path
        end

        found_specs.each do |found_spec|
          found_spec.activate
        end
      end

      return gem_original_require path
    end
  rescue LoadError => load_error
    if load_error.message.end_with?(path) and Gem.try_activate(path) then
      return gem_original_require(path)
    end

    raise load_error
  end

  private :require

end

我可以在本地运行我的应用程序rails -s,但我似乎无法将其发布到Heroku.

Answer 1

iltempo和buru的回答帮助了我:

sudo apt-get install libreadline-dev

rvm remove 1.9.3

rvm install 1.9.3

Then add to your Gemfile:

gem 'rb-readline'

Answer 2

为我工作:

gem install rb-readline

Answer 3

当您的rvm ruby​​在没有readline扩展的情况下编译时会发生这样的错误(当在ruby编译之前没有安装readline头时会发生这种情况).因此,请尝试以下操作:安装libreadline-dev,然后重新安装ruby:

rvm remove 1.9.3 
rvm install 1.9.3

Answer 4

让它适合我!

gem 'rb-readline', "~> 0.5.0.pre.1", :require => false

Answer 5

此链接是Google搜索中的第一个链接,因此我将清除由最佳答案引起的一些混淆.

最佳答案实际上是两个答案合并为一个.他们两个都会自己解决你的问题,两者都有自己的优点和缺点.

第一个是安装libreadline-dev和重新编译Ruby.这导致Ruby被编译为C readline支持.它可能更快,但为你的Ruby添加了另一个C依赖,并且有它自己的一些缺点(例如,你不能确定你的linux发行版附带了GNU readline,它具有更多功能但是在LGPL许可证上).它也不适用于某些平台(Windows).

第二个是rb-readline通过将其放在Gemfile中或通过全局安装来安装(不建议使用,因为您可能会切换到不同的Ruby版本并再次遇到相同的问题).这对某些人来说更好,因为你现在拥有适用于每个平台的纯Ruby实现,但是需要你在Gemfile中指定它(这应该不是什么大问题)并且可能更慢.说实话,我找不到任何问题了.

最后的选择当然是你的,但是如果你在同一台机器上运行多个项目或多个Ruby版本,我会选择安装libreadline-dev或者你的发行版需要的任何东西,主要是因为你只需要做一次然后所有新编译红宝石将开箱即用.但是,如果你试图只运行这个项目,使用"怪异"平台(Windows),rb-readline可能就要走了.

Answer 6

安装Ruby依赖项的最简单方法是运行：

rvm remove 1.9.3

然后

rvm install 1.9.3

在最后一个命令实际安装ruby之前，它将要求您安装依赖项。就我而言，我得到以下提示：

sudo apt-get install build-essential openssl libreadline6 libreadline6-dev curl git-core zlib1g zlib1g-dev libssl-dev libyaml-dev libsqlite3-dev sqlite3 libxml2-dev libxslt-dev autoconf libc6-dev ncurses-dev automake libtool bison subversion pkg-config

在继续安装之前，应在另一个终端上运行它。

Answer 7

听起来你的应用程序需要 readline gem，但你的 Gemfile 中没有指定。请尝试添加它。