Ruby 在生产服务器上编译资产时出错

我尝试使用Capistrano部署Rails应用程序，但出现以下错误：

NoMethodError: undefined method `to_h' for nil:NilClass

这是堆栈跟踪，看起来可能是链轮问题，但我不知道为什么：

/var/www/paperless_office/shared/bundle/ruby/1.9.1/gems/sprockets-es6-0.9.0/lib/sprockets/es6.rb:14:in `configuration_hash'
/var/www/paperless_office/shared/bundle/ruby/1.9.1/gems/sprockets-es6-0.9.0/lib/sprockets/es6.rb:40:in `configuration_hash'
/var/www/paperless_office/shared/bundle/ruby/1.9.1/gems/sprockets-es6-0.9.0/lib/sprockets/es6.rb:44:in `initialize'
/var/www/paperless_office/shared/bundle/ruby/1.9.1/gems/sprockets-es6-0.9.0/lib/sprockets/es6.rb:21:in `new'
/var/www/paperless_office/shared/bundle/ruby/1.9.1/gems/sprockets-es6-0.9.0/lib/sprockets/es6.rb:21:in `instance'
/var/www/paperless_office/shared/bundle/ruby/1.9.1/gems/sprockets-es6-0.9.0/lib/sprockets/es6.rb:34:in `call'
/var/www/paperless_office/shared/bundle/ruby/1.9.1/gems/sprockets-3.5.2/lib/sprockets/processor_utils.rb:75:in `call_processor'
/var/www/paperless_office/shared/bundle/ruby/1.9.1/gems/sprockets-3.5.2/lib/sprockets/processor_utils.rb:57:in `block in call_processors'
/var/www/paperless_office/shared/bundle/ruby/1.9.1/gems/sprockets-3.5.2/lib/sprockets/processor_utils.rb:56:in `reverse_each'
/var/www/paperless_office/shared/bundle/ruby/1.9.1/gems/sprockets-3.5.2/lib/sprockets/processor_utils.rb:56:in `call_processors'
/var/www/paperless_office/shared/bundle/ruby/1.9.1/gems/sprockets-3.5.2/lib/sprockets/loader.rb:134:in `load_from_unloaded'
/var/www/paperless_office/shared/bundle/ruby/1.9.1/gems/sprockets-3.5.2/lib/sprockets/loader.rb:60:in `block in load'
/var/www/paperless_office/shared/bundle/ruby/1.9.1/gems/sprockets-3.5.2/lib/sprockets/loader.rb:318:in `fetch_asset_from_dependency_cache'
/var/www/paperless_office/shared/bundle/ruby/1.9.1/gems/sprockets-3.5.2/lib/sprockets/loader.rb:44:in `load'
/var/www/paperless_office/shared/bundle/ruby/1.9.1/gems/sprockets-3.5.2/lib/sprockets/cached_environment.rb:20:in `block in initialize'
/var/www/paperless_office/shared/bundle/ruby/1.9.1/gems/sprockets-3.5.2/lib/sprockets/cached_environment.rb:47:in `yield'
/var/www/paperless_office/shared/bundle/ruby/1.9.1/gems/sprockets-3.5.2/lib/sprockets/cached_environment.rb:47:in `default'
/var/www/paperless_office/shared/bundle/ruby/1.9.1/gems/sprockets-3.5.2/lib/sprockets/cached_environment.rb:47:in `load'
/var/www/paperless_office/shared/bundle/ruby/1.9.1/gems/sprockets-3.5.2/lib/sprockets/bundle.rb:23:in `block in call'
/var/www/paperless_office/shared/bundle/ruby/1.9.1/gems/sprockets-3.5.2/lib/sprockets/utils.rb:183:in `dfs'
/var/www/paperless_office/shared/bundle/ruby/1.9.1/gems/sprockets-3.5.2/lib/sprockets/bundle.rb:24:in `call'
/var/www/paperless_office/shared/bundle/ruby/1.9.1/gems/sprockets-3.5.2/lib/sprockets/processor_utils.rb:75:in `call_processor'
/var/www/paperless_office/shared/bundle/ruby/1.9.1/gems/sprockets-3.5.2/lib/sprockets/processor_utils.rb:57:in `block in call_processors'
/var/www/paperless_office/shared/bundle/ruby/1.9.1/gems/sprockets-3.5.2/lib/sprockets/processor_utils.rb:56:in `reverse_each'
/var/www/paperless_office/shared/bundle/ruby/1.9.1/gems/sprockets-3.5.2/lib/sprockets/processor_utils.rb:56:in `call_processors'
/var/www/paperless_office/shared/bundle/ruby/1.9.1/gems/sprockets-3.5.2/lib/sprockets/loader.rb:134:in `load_from_unloaded'
/var/www/paperless_office/shared/bundle/ruby/1.9.1/gems/sprockets-3.5.2/lib/sprockets/loader.rb:60:in `block in load'
/var/www/paperless_office/shared/bundle/ruby/1.9.1/gems/sprockets-3.5.2/lib/sprockets/loader.rb:318:in `fetch_asset_from_dependency_cache'
/var/www/paperless_office/shared/bundle/ruby/1.9.1/gems/sprockets-3.5.2/lib/sprockets/loader.rb:44:in `load'
/var/www/paperless_office/shared/bundle/ruby/1.9.1/gems/sprockets-3.5.2/lib/sprockets/cached_environment.rb:20:in `block in initialize'
/var/www/paperless_office/shared/bundle/ruby/1.9.1/gems/sprockets-3.5.2/lib/sprockets/cached_environment.rb:47:in `yield'
/var/www/paperless_office/shared/bundle/ruby/1.9.1/gems/sprockets-3.5.2/lib/sprockets/cached_environment.rb:47:in `default'
/var/www/paperless_office/shared/bundle/ruby/1.9.1/gems/sprockets-3.5.2/lib/sprockets/cached_environment.rb:47:in `load'
/var/www/paperless_office/shared/bundle/ruby/1.9.1/gems/sprockets-3.5.2/lib/sprockets/base.rb:66:in `find_asset'
/var/www/paperless_office/shared/bundle/ruby/1.9.1/gems/sprockets-3.5.2/lib/sprockets/base.rb:73:in `find_all_linked_assets'
/var/www/paperless_office/shared/bundle/ruby/1.9.1/gems/sprockets-3.5.2/lib/sprockets/manifest.rb:142:in `block in find'
/var/www/paperless_office/shared/bundle/ruby/1.9.1/gems/sprockets-3.5.2/lib/sprockets/legacy.rb:114:in `block (2 levels) in logical_paths'
/var/www/paperless_office/shared/bundle/ruby/1.9.1/gems/sprockets-3.5.2/lib/sprockets/path_utils.rb:225:in `block in stat_tree'
/var/www/paperless_office/shared/bundle/ruby/1.9.1/gems/sprockets-3.5.2/lib/sprockets/path_utils.rb:209:in `block in stat_directory'
/var/www/paperless_office/shared/bundle/ruby/1.9.1/gems/sprockets-3.5.2/lib/sprockets/path_utils.rb:206:in `each'
/var/www/paperless_office/shared/bundle/ruby/1.9.1/gems/sprockets-3.5.2/lib/sprockets/path_utils.rb:206:in `stat_directory'
/var/www/paperless_office/shared/bundle/ruby/1.9.1/gems/sprockets-3.5.2/lib/sprockets/path_utils.rb:224:in `stat_tree'
/var/www/paperless_office/shared/bundle/ruby/1.9.1/gems/sprockets-3.5.2/lib/sprockets/legacy.rb:105:in `each'
/var/www/paperless_office/shared/bundle/ruby/1.9.1/gems/sprockets-3.5.2/lib/sprockets/legacy.rb:105:in `block in logical_paths'
/var/www/paperless_office/shared/bundle/ruby/1.9.1/gems/sprockets-3.5.2/lib/sprockets/legacy.rb:104:in `each'
/var/www/paperless_office/shared/bundle/ruby/1.9.1/gems/sprockets-3.5.2/lib/sprockets/legacy.rb:104:in `logical_paths'
/var/www/paperless_office/shared/bundle/ruby/1.9.1/gems/sprockets-3.5.2/lib/sprockets/manifest.rb:140:in `find'
/var/www/paperless_office/shared/bundle/ruby/1.9.1/gems/sprockets-3.5.2/lib/sprockets/manifest.rb:168:in `compile'
/var/www/paperless_office/shared/bundle/ruby/1.9.1/gems/sprockets-rails-2.3.3/lib/sprockets/rails/task.rb:70:in `block (3 levels) in define'
/var/www/paperless_office/shared/bundle/ruby/1.9.1/gems/sprockets-3.5.2/lib/rake/sprocketstask.rb:147:in `with_logger'
/var/www/paperless_office/shared/bundle/ruby/1.9.1/gems/sprockets-rails-2.3.3/lib/sprockets/rails/task.rb:69:in `block (2 levels) in define'
Tasks: TOP => assets:precompile

这是我当地的环境：

OSX 10.11.3
Ruby 2.1.3p242
Rails 4.1.0
Rake 10.3.2
Sprockets-Rails 2.3.3
Capistrano 3.4.0

Centos 5
ruby 2.1.3p242 (managed by rbenv)

这是我的生产环境：

OSX 10.11.3
Ruby 2.1.3p242
Rails 4.1.0
Rake 10.3.2
Sprockets-Rails 2.3.3
Capistrano 3.4.0

Centos 5
ruby 2.1.3p242 (managed by rbenv)

我当前安装的gems是：

bigdecimal (1.2.4)
bundler (1.11.2)
io-console (0.4.2)
json (1.8.1)
minitest (4.7.5)
psych (2.0.5)
rake (10.1.0)
rdoc (4.1.0)
test-unit (2.1.3.0)

我已经能够运行：

gem install bundler

但是，如果我运行：

gem install rails

我得到：

ERROR:  While executing gem ... (Gem::RemoteFetcher::FetchError)
    bad response Service Unavailable 503 (https://api.rubygems.org/api/v1/dependencies?gems=rack)

---

这与我最初的问题有关联吗？

对于任何遇到这一问题的人来说，由于@DavidK-J发布的链接为我指明了正确的方向，问题得以解决。我需要使用rbenv的设置更新cap文件，如下所示：

卡普里

require 'capistrano/rbenv'

deploy.rb

set :rbenv_type, :system
set :rbenv_path, '~/.rbenv'
set :rbenv_ruby, "2.1.3"
set :rbenv_prefix, "RBENV_ROOT=#{fetch(:rbenv_path)} RBENV_VERSION=#{fetch(:rbenv_ruby)} #{fetch(:rbenv_path)}/bin/rbenv exec"
set :rbenv_map_bins, %w{rake gem bundle ruby rails}
set :rbenv_roles, :all

然后，我必须用rbenv的路径更新乘客配置，在我的情况下，该路径是：

~/.rbenv

还有其他人

---

Paul

你确定这不是Rubygems站点的一个短暂故障吗？

未定义的方法“to_h”for nil:NilClass

“告诉我们的不多。它还应该告诉你行号和它所在的文件。您有一个未初始化的值，但我们不知道它是什么。您发布了日志中不可用的部分，而这部分是在ruby 1.9.1下运行的。也许这就是问题所在？正如Mike之前提到的，Capistrano似乎在运行不同的Ruby。也许是你？@David K-J谢谢，那篇帖子似乎可以解决这个问题。直到星期四我才能再次访问服务器，因此我将在星期四再试一次。