如何在RSpec中测试信号处理,特别是处理SIGTERM？

Question

Heroku可能出于各种原因向您的应用程序发送SIGTERM,因此我创建了一个处理程序来处理一些清理,以防万一.一些谷歌搜索没有得到任何关于如何在RSpec中测试这个的答案或例子.这是基本代码:

Signal.trap('TERM') do  
    cleanup  
end

def cleanup
    puts "doing some cleanup stuff"
    ...
    exit
end

测试程序收到SIGTERM时调用此清理方法的最佳方法是什么？

Answer 1

杀了自己!将信号发送到RSpec Process.kill 'TERM', 0并测试处理程序是否被调用.确实如果信号没有被捕获,测试将崩溃而不是很好地报告失败,但至少你会知道代码中存在问题.

例如:

class SignalHandler
  def self.trap_signals
    Signal.trap('TERM') { term_handler }
  end

  def self.term_handler
    # ...
  end

end

describe SignalHandler do
  describe '#trap_signals' do
    it "traps TERM" do
      # The MRI default TERM handler does not cause RSpec to exit with an error.
      # Use the system default TERM handler instead, which does kill RSpec.
      # If you test a different signal you might not need to do this,
      # or you might need to install a different signal's handler.
      old_signal_handler = Signal.trap 'TERM', 'SYSTEM_DEFAULT'

      SignalHandler.trap_signals
      expect(SignalHandler).to receive(:term_handler).with no_args
      Process.kill 'TERM', 0 # Send the signal to ourself

      # Put the Ruby default signal handler back in case it matters to other tests
      Signal.trap 'TERM', old_signal_handler
    end
  end
end

我只是测试了处理程序被调用,但你同样可以测试处理程序的副作用.