Capistrano 资产预编译错误答案

【问题标题】：Capistrano asset precompile errorCapistrano 资产预编译错误
【发布时间】：2012-07-28 23:33:41
【问题描述】：

当我使用 capistrano 推送到我的生产服务器时，我收到此错误：

executing "cd /var/www/my_app/releases/20120731082050 && bundle exec rake RAILS_ENV=production RAILS_GROUPS=assets assets:precompile"
servers: ["my_app.com"]
[my_app.com] executing command
*** [err :: my_app.com] /usr/bin/ruby1.9.1 /var/www/my_app/shared/bundle/ruby/1.9.1/bin/rake assets:precompile:nondigest RAILS_ENV=production RAILS_GROUPS=assets
*** [err :: my_app.com] 
command finished in 74149ms

尽管出现错误，预编译仍然有效。我试过跑步

cd /var/www/my_app/releases/20120731082050 && bundle exec rake RAILS_ENV=production RAILS_GROUPS=assets assets:precompile

在服务器上它可以工作，但它会打印到控制台：

/usr/bin/ruby1.9.1 /var/www/my_app/shared/bundle/ruby/1.9.1/bin/rake assets:precompile:nondigest RAILS_ENV=production RAILS_GROUPS=assets

与 capistrano 输出相匹配（请注意在原始调用中添加了“nondigest”。我知道这不是致命错误，因为它仍然有效，但我将如何阻止它打印此错误？

【问题讨论】：

尝试将 --trace 放在末尾以获得完整的堆栈跟踪，即： cd /var/www/my_app/releases/20120731082050 && bundle exec rake RAILS_ENV=production RAILS_GROUPS=assets assets:precompile - -trace

标签： ruby-on-rails ruby-on-rails-3 ruby-on-rails-3.1 capistrano sprockets

【解决方案1】：

我刚刚用自己的代码覆盖了deploy:assets 任务：

namespace :deploy
  task :assets do
    run "cd #{current_path} && bundle exec rake assets:precompile RAILS_ENV=#{rails_env}"
  end
end

【讨论】：

【解决方案2】：

运行rake assets:precompile时，如何避免默认输出

解决方案是根据您的命令添加-q，

例如executing "cd /var/www/my_app/releases/20120731082050 && bundle exec rake RAILS_ENV=production RAILS_GROUPS=assets assets:precompile -q"

分析如下，如果你想看：

# :gem_path/actionpack/lib/sprockets/assets.rake
namespace :assets do

  # task entry, it will call invoke_or_reboot_rake_task
  task :precompile do
    invoke_or_reboot_rake_task "assets:precompile:all"
  end

  # it will call ruby_rake_task
  def invoke_or_reboot_rake_task(task)
    ruby_rake_task task
  end

  # it will call ruby
  def ruby_rake_task(task, fork = true)
    env    = ENV['RAILS_ENV'] || 'production'
    groups = ENV['RAILS_GROUPS'] || 'assets'
    args   = [$0, task,"RAILS_ENV=#{env}","RAILS_GROUPS=#{groups}"]
    ruby(*args)
  end
end

# :gem_path/rake/file_utils.rb
module FileUtils

  # it will call sh
  def ruby(*args,&block)
    options = (Hash === args.last) ? args.pop : {}
    sh(*([RUBY] + args + [options]), &block)
  end

  # it will call set_verbose_option
  # and if options[:verbose] == true, it do not output cmd
  #   but default of options[:verbose] is an object
  def sh(*cmd, &block)
    # ...
    set_verbose_option(options)
    # ...
    Rake.rake_output_message cmd.join(" ") if options[:verbose]
    # ...
  end

  # default of options[:verbose] is Rake::FileUtilsExt::DEFAULT, which is an object
  def set_verbose_option(options) # :nodoc:
    unless options.key? :verbose
      options[:verbose] =
        Rake::FileUtilsExt.verbose_flag == Rake::FileUtilsExt::DEFAULT ||
        Rake::FileUtilsExt.verbose_flag
    end
  end
end

# :gem_path/rake/file_utils_ext.rb
module Rake
  module FileUtilsExt
    DEFAULT = Object.new
  end
end

# :gem_path/rake/application.rb
          # the only to solve the disgusting output when run `rake assets:precompile`
          #   is add a `-q` option.
          ['--quiet', '-q',
            "Do not log messages to standard output.",
            lambda { |value| Rake.verbose(false) }
          ],
          ['--verbose', '-v',
            "Log message to standard output.",
            lambda { |value| Rake.verbose(true) }
          ],

【讨论】：