Log4r 配置器在实例化 EmailOutputter 时抛出异常答案

【问题标题】：Log4r configurator throws exception instantiating EmailOutputterLog4r 配置器在实例化 EmailOutputter 时抛出异常
【发布时间】：2014-01-14 17:06:15
【问题描述】：

我正在使用 XML 配置文件设置 Log4r，但我无法让 EmailOutputter 正常工作。这是我的输出器标签：

<outputter type="EmailOutputter" name="exception_email" trunc="false" level="ERROR" buffsize="10">
        <formatter type="PatternFormatter" pattern="#{pattern}"/>
        <server>#{smtp_address}</server>
        <port>#{smtp_port}</port>
        <domain>#{smtp_domain}</domain>
        <from>logging@#{smtp_domain}</from>
        <to>exceptions@mydomain.com</to>
        <subject>Log Report</subject>
        <immediate_at>ERROR, FATAL</immediate_at>
      </outputter>

我已经使用 RubyMine 逐步调试器检查了所有 XML 变量是否正确传递了三重和四重。异常消息是：

未捕获的异常：创建输出器时出现问题：未初始化的常量 Log4r::Configurator::EmailOutputter /usr/local/lib/ruby/gems/1.9.1/gems/log4r-1.1.10/lib/log4r/configurator.rb:87:in block in decode_xml' /usr/local/lib/ruby/1.9.1/rexml/element.rb:905:inblock in each' /usr/local/lib/ruby/1.9.1/rexml/xpath.rb:67:in each' /usr/local/lib/ruby/1.9.1/rexml/xpath.rb:67:ineach' /usr/local/lib/ruby/1.9.1/rexml/element.rb:905:in each' /usr/local/lib/ruby/gems/1.9.1/gems/log4r-1.1.10/lib/log4r/configurator.rb:87:indecode_xml' /usr/local/lib/ruby/gems/1.9.1/gems/log4r-1.1.10/lib/log4r/configurator.rb:82:in actual_load' /usr/local/lib/ruby/gems/1.9.1/gems/log4r-1.1.10/lib/log4r/configurator.rb:56:inload_xml_file' /root/src/upside/common/upside_logger.rb:16:in initialize' /root/src/upside/common/logger_factory.rb:7:innew' /root/src/upside/common/logger_factory.rb:7:in new_logger' /root/src/upside/config/application.rb:30:inblock in ' /usr/local/lib/ruby/gems/1.9.1/gems/activesupport-3.2.11/lib/active_support/lazy_load_hooks.rb:34:in call' /usr/local/lib/ruby/gems/1.9.1/gems/activesupport-3.2.11/lib/active_support/lazy_load_hooks.rb:34:inexecute_hook' /usr/local/lib/ruby/gems/1.9.1/gems/activesupport-3.2.11/lib/active_support/lazy_load_hooks.rb:26:in block in on_load' /usr/local/lib/ruby/gems/1.9.1/gems/activesupport-3.2.11/lib/active_support/lazy_load_hooks.rb:25:ineach' /usr/local/lib/ruby/gems/1.9.1/gems/activesupport-3.2.11/lib/active_support/lazy_load_hooks.rb:25:in on_load' /usr/local/lib/ruby/gems/1.9.1/gems/railties-3.2.11/lib/rails/railtie/configuration.rb:43:inbefore_configuration' /root/src/upside/config/application.rb:29:in <class:Application>' /root/src/upside/config/application.rb:15:in' /root/src/upside/config/application.rb:14:in <top (required)>' /usr/local/lib/ruby/gems/1.9.1/gems/railties-3.2.11/lib/rails/commands.rb:53:inrequire' /usr/local/lib/ruby/gems/1.9.1/gems/railties-3.2.11/lib/rails/commands.rb:53:in block in <top (required)>' /usr/local/lib/ruby/gems/1.9.1/gems/railties-3.2.11/lib/rails/commands.rb:50:intap' /usr/local/lib/ruby/gems/1.9.1/gems/railties-3.2.11/lib/rails/commands.rb:50:in <top (required)>' /root/src/upside/script/rails:6:inrequire' /root/src/upside/script/rails:6:in `'

我已经仔细检查了 gem 安装，并且 emailoutputter.rb 与其他输出器（功能正常）位于正确的目录中。

谢谢！

【问题讨论】：

标签： ruby-on-rails log4r

【解决方案1】：

我发现 log4r 文件 lib/log4r.rb 缺少行 require "log4r/outputter/emailoutputter"。在config/initializer 文件中将这个缺失的require 添加到我的Rails 应用程序允许EmailOutputter 类可用。

【讨论】：

我发现了同样的事情。