Question

我目前在使用扭曲的python库访问通过https托管的内容时遇到了一些问题。我是这个图书馆的新手，我假设有一些我错过的概念引起了这个问题，但可能不是基于这个例子。

以下是我收集示例的页面的链接： https://twistedmatrix.com/documents/current/web/howto/client.html

标题 HTTP over SSL 标题下

＆＃13;

from twisted.python.log import err
from twisted.web.client import Agent
from twisted.internet import reactor
from twisted.internet.ssl import optionsForClientTLS

def display(response):
    print("Received response")
    print(response)

def main():
    contextFactory = optionsForClientTLS(u"https://example.com/")
    agent = Agent(reactor, contextFactory)
    d = agent.request("GET", "https://example.com/")
    d.addCallbacks(display, err)
    d.addCallback(lambda ignored: reactor.stop())
    reactor.run()

if __name__ == "__main__":
    main()

＆＃13;

运行此代码时，它直接启动失败。我得到一个如下错误：

＆＃13;

Traceback (most recent call last):
  File "https.py", line 19, in <module>
    main()
  File "https.py", line 11, in main
    contextFactory = optionsForClientTLS(u"https://example.com/")
  File "/home/amaricich/.local/lib/python2.7/site-packages/twisted/internet/_sslverify.py", line 1336, in optionsForClientTLS
    return ClientTLSOptions(hostname, certificateOptions.getContext())
  File "/home/amaricich/.local/lib/python2.7/site-packages/twisted/internet/_sslverify.py", line 1198, in __init__
    self._hostnameBytes = _idnaBytes(hostname)
  File "/home/amaricich/.local/lib/python2.7/site-packages/twisted/internet/_sslverify.py", line 86, in _idnaBytes
    return idna.encode(text)
  File "/usr/local/lib/python2.7/dist-packages/idna/core.py", line 355, in encode
    result.append(alabel(label))
  File "/usr/local/lib/python2.7/dist-packages/idna/core.py", line 276, in alabel
    check_label(label)
  File "/usr/local/lib/python2.7/dist-packages/idna/core.py", line 253, in check_label
    raise InvalidCodepoint('Codepoint {0} at position {1} of {2} not allowed'.format(_unot(cp_value), pos+1, repr(label)))
idna.core.InvalidCodepoint: Codepoint U+003A at position 6 of u'https://example' not allowed

＆＃13;

此错误让我相信传入 optionsForClientTLS 的参数不正确。它需要主机名而不是完整的URL，因此我将参数缩短为 example.com 。完成更改后，该功能成功完成。

不幸的是，在进行更改后，脚本现在在调用 agent.request 的行中失败了。它提供的错误是：

＆＃13;

Traceback (most recent call last):
  File "https.py", line 19, in <module>
    main()
  File "https.py", line 13, in main
    d = agent.request("GET", "https://example.com/")
  File "/home/amaricich/.local/lib/python2.7/site-packages/twisted/web/client.py", line 1596, in request
    endpoint = self._getEndpoint(parsedURI)
  File "/home/amaricich/.local/lib/python2.7/site-packages/twisted/web/client.py", line 1580, in _getEndpoint
    return self._endpointFactory.endpointForURI(uri)
  File "/home/amaricich/.local/lib/python2.7/site-packages/twisted/web/client.py", line 1456, in endpointForURI
    uri.port)
  File "/home/amaricich/.local/lib/python2.7/site-packages/twisted/web/client.py", line 982, in creatorForNetloc
    context = self._webContextFactory.getContext(hostname, port)
AttributeError: 'ClientTLSOptions' object has no attribute 'getContext'

＆＃13;

这个错误让我相信optionsForClientTLS生成的对象不是预期在创建时传递给代理的对象类型。正在尝试调用不存在的函数。尽管如此，我有两个问题。

此示例是否已弃用？以前的示例使http请求都像魅力一样工作。我做错了什么，或者示例不再有效？
我只是在寻找一种使用HTTPS从服务器检索数据的简单方法。如果以这种方式做事不是解决方案，那么是否有人熟悉如何使用twisted进行HTTPS请求？

Answer 1

是的，您绝对正确，文档上的示例是错误的。我注意到了错误while working w/ treq。从v14开始尝试关注this example。话虽如此，你应该使用treq而不是试图直接使用Twisted。大部分的重物都已经为你照顾好了。这是对您的示例的简单转换：

from __future__ import print_function
import treq
from twisted.internet import defer, task
from twisted.python.log import err

@defer.inlineCallbacks
def display(response):
    content = yield treq.content(response)
    print('Content: {0}'.format(content))

def main(reactor):
    d = treq.get('https://twistedmatrix.com')
    d.addCallback(display)
    d.addErrback(err)
    return d

task.react(main)

正如您所见，treq为您处理SSL问题。 display()回调函数可用于提取HTTP响应的各种组件，例如标题，状态代码，正文等。如果您只需要一个组件，例如响应主体，那么您可以进一步简化像这样：

def main(reactor):
    d = treq.get('https://twistedmatrix.com')
    d.addCallback(treq.content)     # get response content when available
    d.addErrback(err)
    d.addCallback(print)
    return d

task.react(main)

扭曲的HTTPS客户端

1 个答案: