如何使用Ruby Rest-Client处理异常

Question

我最近从Ruby的Net:HTTP类切换到了rest-client 1.6.7。

我发现形成请求要容易得多，但与Net:HTTP请求不同的是，当rest-client获得200以外的任何值时，请求就会终止。我试着把断点直接放在RestClient.get后面，但它从来没有命中过--所以我做错了什么。

def get_member_using_card
  resource = "#{@settings_app_uri}api/v1/card/#{self.member_card_num}?token=#{@settings.api_key}"
  response = RestClient.get resource
  if response.code == 200 
    card = JSON.parse(response.body)
    self.customer_id = card['card']['customer_id']
  else
    return 0
  end
end

这将导致此堆栈跟踪：

RestClient::ResourceNotFound - 404 Resource Not Found:
        /Users/tim/.rvm/gems/ruby-1.9.2-p290/gems/rest-client-1.6.7/lib/restclient/abstr
act_response.rb:48:in `return!'
        /Users/tim/.rvm/gems/ruby-1.9.2-p290/gems/rest-client-1.6.7/lib/restclient/reque
st.rb:230:in `process_result'
        /Users/tim/.rvm/gems/ruby-1.9.2-p290/gems/rest-client-1.6.7/lib/restclient/reque
st.rb:178:in `block in transmit'
        /Users/tim/.rvm/rubies/ruby-1.9.2-p290/lib/ruby/1.9.1/net/http.rb:627:in `start'
        /Users/tim/.rvm/gems/ruby-1.9.2-p290/gems/rest-client-1.6.7/lib/restclient/reque
st.rb:172:in `transmit'
        /Users/tim/.rvm/gems/ruby-1.9.2-p290/gems/rest-client-1.6.7/lib/restclient/reque
st.rb:64:in `execute'
        /Users/tim/.rvm/gems/ruby-1.9.2-p290/gems/rest-client-1.6.7/lib/restclient/reque
st.rb:33:in `execute'
        /Users/tim/.rvm/gems/ruby-1.9.2-p290/gems/rest-client-1.6.7/lib/restclient.rb:68
:in `get'

谁能告诉我如何正确地评估响应代码并防止这种异常发生……？

Answer 1

请参见标题Exceptions on http://rubydoc.info/gems/rest-client/

对于200和207之间的结果代码，将返回

• 对于结果代码301、302或307，将返回
• 如果结果代码303的请求是get或head
• ，则将遵循重定向，并且将请求转换为get

异常对于其他情况，将引发保存响应的RestClient：：

• ，对于已知错误代码，将抛出特定异常类

< code >F212

RestClient.get 'http://example.com/resource'
➔ RestClient::ResourceNotFound: RestClient::ResourceNotFound`

begin
  RestClient.get 'http://example.com/resource'
rescue => e
  e.response
end
➔ 404 Resource Not Found | text/html 282 bytes

Answer 2

同样在相同的文档@wich中，您可以向RestClient.get传递一个块，这样它就不会在非200响应代码上抛出异常：

# Don't raise exceptions but return the response
RestClient.get('http://example.com/resource'){|response, request, result| response }

请参阅“结果处理”部分from the documentation。

Answer 3

rescue RestClient::ExceptionWithResponse => err