【发布时间】：2017-08-31 15:52:53
【问题描述】：
首次将 Rails 应用程序部署到新服务器。
运行cap production deploy --trace 给了我：
** Invoke production (first_time)
** Execute production
** Invoke load:defaults (first_time)
** Execute load:defaults
cap aborted!
NoMethodError: undefined method `upcase' for nil:NilClass
/Users/dfaulken-af/.rbenv/versions/2.4.1/lib/ruby/gems/2.4.0/gems/sshkit-1.14.0/lib/sshkit/configuration.rb:90:in `logger'
/Users/dfaulken-af/.rbenv/versions/2.4.1/lib/ruby/gems/2.4.0/gems/sshkit-1.14.0/lib/sshkit/configuration.rb:51:in `output_verbosity='
/Users/dfaulken-af/.rbenv/versions/2.4.1/lib/ruby/gems/2.4.0/gems/capistrano-3.9.0/lib/capistrano/configuration.rb:94:in `block in configure_backend'
/Users/dfaulken-af/.rbenv/versions/2.4.1/lib/ruby/gems/2.4.0/gems/sshkit-1.14.0/lib/sshkit.rb:11:in `configure'
/Users/dfaulken-af/.rbenv/versions/2.4.1/lib/ruby/gems/2.4.0/gems/capistrano-3.9.0/lib/capistrano/configuration.rb:92:in `configure_backend'
/Users/dfaulken-af/.rbenv/versions/2.4.1/lib/ruby/gems/2.4.0/gems/capistrano-3.9.0/lib/capistrano/setup.rb:32:in `block (2 levels) in <top (required)>'
/Users/dfaulken-af/.rbenv/versions/2.4.1/lib/ruby/gems/2.4.0/gems/rake-12.0.0/lib/rake/task.rb:250:in `block in execute'
/Users/dfaulken-af/.rbenv/versions/2.4.1/lib/ruby/gems/2.4.0/gems/rake-12.0.0/lib/rake/task.rb:250:in `each'
/Users/dfaulken-af/.rbenv/versions/2.4.1/lib/ruby/gems/2.4.0/gems/rake-12.0.0/lib/rake/task.rb:250:in `execute'
/Users/dfaulken-af/.rbenv/versions/2.4.1/lib/ruby/gems/2.4.0/gems/rake-12.0.0/lib/rake/task.rb:194:in `block in invoke_with_call_chain'
/Users/dfaulken-af/.rbenv/versions/2.4.1/lib/ruby/2.4.0/monitor.rb:214:in `mon_synchronize'
/Users/dfaulken-af/.rbenv/versions/2.4.1/lib/ruby/gems/2.4.0/gems/rake-12.0.0/lib/rake/task.rb:187:in `invoke_with_call_chain'
/Users/dfaulken-af/.rbenv/versions/2.4.1/lib/ruby/gems/2.4.0/gems/rake-12.0.0/lib/rake/task.rb:180:in `invoke'
/Users/dfaulken-af/.rbenv/versions/2.4.1/lib/ruby/gems/2.4.0/gems/rake-12.0.0/lib/rake/application.rb:152:in `invoke_task'
/Users/dfaulken-af/.rbenv/versions/2.4.1/lib/ruby/gems/2.4.0/gems/rake-12.0.0/lib/rake/application.rb:108:in `block (2 levels) in top_level'
/Users/dfaulken-af/.rbenv/versions/2.4.1/lib/ruby/gems/2.4.0/gems/rake-12.0.0/lib/rake/application.rb:108:in `each'
/Users/dfaulken-af/.rbenv/versions/2.4.1/lib/ruby/gems/2.4.0/gems/rake-12.0.0/lib/rake/application.rb:108:in `block in top_level'
/Users/dfaulken-af/.rbenv/versions/2.4.1/lib/ruby/gems/2.4.0/gems/rake-12.0.0/lib/rake/application.rb:117:in `run_with_threads'
/Users/dfaulken-af/.rbenv/versions/2.4.1/lib/ruby/gems/2.4.0/gems/rake-12.0.0/lib/rake/application.rb:102:in `top_level'
/Users/dfaulken-af/.rbenv/versions/2.4.1/lib/ruby/gems/2.4.0/gems/rake-12.0.0/lib/rake/application.rb:80:in `block in run'
/Users/dfaulken-af/.rbenv/versions/2.4.1/lib/ruby/gems/2.4.0/gems/rake-12.0.0/lib/rake/application.rb:178:in `standard_exception_handling'
/Users/dfaulken-af/.rbenv/versions/2.4.1/lib/ruby/gems/2.4.0/gems/rake-12.0.0/lib/rake/application.rb:77:in `run'
/Users/dfaulken-af/.rbenv/versions/2.4.1/lib/ruby/gems/2.4.0/gems/capistrano-3.9.0/lib/capistrano/application.rb:14:in `run'
/Users/dfaulken-af/.rbenv/versions/2.4.1/lib/ruby/gems/2.4.0/gems/capistrano-3.9.0/bin/cap:3:in `<top (required)>'
/Users/dfaulken-af/.rbenv/versions/2.4.1/bin/cap:22:in `load'
/Users/dfaulken-af/.rbenv/versions/2.4.1/bin/cap:22:in `<main>'
Tasks: TOP => production
这似乎完全局限于 gem 代码。在我向他们提出问题（sshkit？）之前，有没有人见过这个？
我使用Net::SSH::Config 从我的 SSH 配置文件中获取 SSH 用户。我知道这些设置是正确的，因为我可以使用它们登录服务器。
remote_user = Net::SSH::Config.for('50.198.83.200')[:user] || ENV['USER']
server '50.198.83.200', user: remote_user, roles: %w(app db web)
但我尝试使用USER=the_user_name cap 等设置远程用户，但仍然出现相同的错误。
【问题讨论】：
标签： ruby-on-rails ssh capistrano