如何在 ruby​​ 中使用 net/http 处理超时，同时向给定 IP 范围内的 IP 发送请求，并跳过超时的 IP 并移至下一个？

Question

我想处理从控制台获取的 IP 范围的超时，我向获取范围内的 IP 发出请求并收到超时错误。 我想向所有 IP 发出请求并获得它们的响应。 对于超时的IP，想跳过它并移至下一个。如何处理这个问题，以便循环不会出现异常，并且脚本将请求发送到所有可以提供响应处理超时的 IP。

在此附加代码：

require 'net/http'
require 'uri'
require 'ipaddr'

puts "Origin IP:"
originip = gets()
(IPAddr.new("209.85.175.121")..IPAddr.new("209.85.175.150")).each do |address|
  req = Net::HTTP.get(URI.parse("http://#{address.to_s}"))
  puts req
end

错误：

C:/Ruby187/lib/ruby/1.8/net/http.rb:560:in `initialize': A connection attempt failed because the connected party did not properly respond after a period of time, or established connection failed because connected host has failed to respond. - connect(2) (Errno::ETIMEDOUT)
        from C:/Ruby187/lib/ruby/1.8/net/http.rb:560:in `open'
        from C:/Ruby187/lib/ruby/1.8/net/http.rb:560:in `connect'
        from C:/Ruby187/lib/ruby/1.8/timeout.rb:53:in `timeout'
        from C:/Ruby187/lib/ruby/1.8/timeout.rb:101:in `timeout'
        from C:/Ruby187/lib/ruby/1.8/net/http.rb:560:in `connect'
        from C:/Ruby187/lib/ruby/1.8/net/http.rb:553:in `do_start'
        from C:/Ruby187/lib/ruby/1.8/net/http.rb:542:in `start'
        from C:/Ruby187/lib/ruby/1.8/net/http.rb:379:in `get_response'
        from C:/Ruby187/lib/ruby/1.8/net/http.rb:356:in `get'
        from IP Range 2.rb:9
        from IP Range 2.rb:8:in `each'

Answer 1

正如马克所说。你应该拯救这个异常。像这样：

begin
  response = Net::HTTP.get(...)
rescue Errno::ECONNREFUSED => e
  # Do what you think needs to be done
end

此外，从调用 get() 中返回的是响应，而不是请求。

Answer 2

使用 timeout 捕获异常，

require 'timeout'

(IPAddr.new("209.85.175.121")..IPAddr.new("209.85.175.150")).each do |address|
  begin
    req = Net::HTTP.get(URI.parse("http://#{address.to_s}"))
    puts req
  rescue Timeout::Error => exc
    puts "ERROR: #{exc.message}"
  rescue Errno::ETIMEDOUT => exc
    puts "ERROR: #{exc.message}"
  # uncomment the following two lines, if you are not able to track the exception type.
  #rescue Exception => exc
  #  puts "ERROR: #{exc.message}"
  end
end

编辑：当我们拯救Timeout::Error，只有那些属于Timeout::Error类的异常才会被捕获。我们需要使用它们的错误类捕获引发的异常，并相应地更新代码。