Question

如果网站返回“503 service unavailable”错误，则open-uri会抛出异常。例如：

require 'open-uri'
open('http://www.google.co.uk/sorry/?continue=http://www.google.co.uk/search%3Fq%3Dhello%26oq%3Dhello%26ie%3DUTF-8')
# OpenURI::HTTPError: 503 Service Unavailable
# ...

但是，如果您随后在网络浏览器中访问它，它实际上会显示一个带有CAPTCHA而不是错误的页面。

如何确保open-uri不仅仅将此作为例外处理，而是实际处理响应并向我提供页面内容？

Answer 1

OpenURI::HTTPError有io属性，您可以检查以获得所需内容。 io是一个StringIO对象，其上定义了多个单例方法（例如status）：

require 'open-uri'
begin
  open('http://www.google.co.uk/sorry/?continue=http://www.google.co.uk/search%3Fq%3Dhello%26oq%3Dhello%26ie%3DUTF-8')
rescue OpenURI::HTTPError => error
  response = error.io
  response.status
  # => ["503", "Service Unavailable"] 
  response.string
  # => <!DOCTYPE html PUBLIC \"-//W3C//DTD HTML 4.01 Transitional//EN\">\n<html DIR=\"LTR\">\n<head><meta http-equiv=\"content-type\" content=\"text/html; charset=utf-8\"><meta name=\"viewport\" content=\"initial-scale=1\">...
end

但是对于此任务，Net::HTTP模块可能是更好的选择：

require 'net/http'
response = Net::HTTP.get_response(URI.parse('http://www.google.co.uk/sorry/?continue=http://www.google.co.uk/search%3Fq%3Dhello%26oq%3Dhello%26ie%3DUTF-8'))
response.code
# => "503"
response.body
# => "<!DOCTYPE html PUBLIC \"-//W3C//DTD HTML 4.01 Transitional//EN\">\n<html DIR=\"LTR\">\n<head><meta http-equiv=\"content-type\" content=\"text/html; ...

如何使用open-uri处理503错误？

1 个答案: