过去几天，我一直在终端中运行以下脚本。我没有对其进行任何更改。以前，它一直运行良好，现在出现错误:

Traceback (most recent call last):
  File "GetAlexRanking.py", line 193, in <module>
    print("%s:%d" % (p.__class__.__name__, p.get_rank(url
TypeError: %d format: a number is required, not NoneType

这是完整的代码。应该可以将它保存在 .py 文件中，使用命令 python filename.py www.google.com 从终端 shell 运行它以打印出 Google 的一些流量统计信息。但是，这将不再对我有用。这里有什么问题？

import struct
import sys
import urllib
import urllib2
import httplib
import re
import xml.etree.ElementTree

class RankProvider(object):
    """Abstract class for obtaining the page rank (popularity)
from a provider such as Google or Alexa.

"""
    def __init__(self, host, proxy=None, timeout=30):
        """Keyword arguments:
host -- toolbar host address
proxy -- address of proxy server. Default: None
timeout -- how long to wait for a response from the server.
Default: 30 (seconds)

"""
        self._opener = urllib2.build_opener()
        if proxy:
            self._opener.add_handler(urllib2.ProxyHandler({"http": proxy}))

        self._host = host
        self._timeout = timeout

    def get_rank(self, url):
        """Get the page rank for the specified URL

Keyword arguments:
url -- get page rank for url

"""
        raise NotImplementedError("You must override get_rank()")


class AlexaTrafficRank(RankProvider):
    """ Get the Alexa Traffic Rank for a URL

"""
    def __init__(self, host="xml.alexa.com", proxy=None, timeout=30):
        """Keyword arguments:
host -- toolbar host address: Default: joolbarqueries.google.com
proxy -- address of proxy server (if required). Default: None
timeout -- how long to wait for a response from the server.
Default: 30 (seconds)

"""
        super(AlexaTrafficRank, self).__init__(host, proxy, timeout)

    def get_rank(self, url):
        """Get the page rank for the specified URL

Keyword arguments:
url -- get page rank for url

"""
        query = "http://%s/data?%s" % (self._host, urllib.urlencode((
            ("cli", 10),
            ("dat", "nsa"),
            ("ver", "quirk-searchstatus"),
            ("uid", "20120730094100"),
            ("userip", "192.168.0.1"),
            ("url", url))))

        response = self._opener.open(query, timeout=self._timeout)
        if response.getcode() == httplib.OK:
            data = response.read()

            element = xml.etree.ElementTree.fromstring(data)
            for e in element.iterfind("SD"):
                popularity = e.find("POPULARITY")
                if popularity is not None:
                    return int(popularity.get("TEXT"))


class GooglePageRank(RankProvider):
    """ Get the google page rank figure using the toolbar API.
Credits to the author of the WWW::Google::PageRank CPAN package
as I ported that code to Python.

"""
    def __init__(self, host="toolbarqueries.google.com", proxy=None, timeout=30):
        """Keyword arguments:
host -- toolbar host address: Default: toolbarqueries.google.com
proxy -- address of proxy server (if required). Default: None
timeout -- how long to wait for a response from the server.
Default: 30 (seconds)

"""
        super(GooglePageRank, self).__init__(host, proxy, timeout)
        self._opener.addheaders = [("User-agent", "Mozilla/4.0 (compatible; \
GoogleToolbar 2.0.111-big; Windows XP 5.1)")]

    def get_rank(self, url):
        # calculate the hash which is required as part of the get
        # request sent to the toolbarqueries url.
        ch = '6' + str(self._compute_ch_new("info:%s" % (url)))

        query = "http://%s/tbr?%s" % (self._host, urllib.urlencode((
            ("client", "navclient-auto"),
            ("ch", ch),
            ("ie", "UTF-8"),
            ("oe", "UTF-8"),
            ("features", "Rank"),
            ("q", "info:%s" % (url)))))

        response = self._opener.open(query, timeout=self._timeout)
        if response.getcode() == httplib.OK:
            data = response.read()
            match = re.match("Rank_\d+:\d+:(\d+)", data)
            if match:
                rank = match.group(1)
                return int(rank)

    @classmethod
    def _compute_ch_new(cls, url):
        ch = cls._compute_ch(url)
        ch = ((ch % 0x0d) & 7) | ((ch / 7) << 2);

        return cls._compute_ch(struct.pack("<20L", *(cls._wsub(ch, i * 9) for i in range(20))))

    @classmethod
    def _compute_ch(cls, url):
        url = struct.unpack("%dB" % (len(url)), url)
        a = 0x9e3779b9
        b = 0x9e3779b9
        c = 0xe6359a60
        k = 0

        length = len(url)

        while length >= 12:
            a = cls._wadd(a, url[k+0] | (url[k+1] << 8) | (url[k+2] << 16) | (url[k+3] << 24));
            b = cls._wadd(b, url[k+4] | (url[k+5] << 8) | (url[k+6] << 16) | (url[k+7] << 24));
            c = cls._wadd(c, url[k+8] | (url[k+9] << 8) | (url[k+10] << 16) | (url[k+11] << 24));

            a, b, c = cls._mix(a, b, c)

            k += 12
            length -= 12

        c = cls._wadd(c, len(url));

        if length > 10: c = cls._wadd(c, url[k+10] << 24)
        if length > 9: c = cls._wadd(c, url[k+9] << 16)
        if length > 8: c = cls._wadd(c, url[k+8] << 8)
        if length > 7: b = cls._wadd(b, url[k+7] << 24)
        if length > 6: b = cls._wadd(b, url[k+6] << 16)
        if length > 5: b = cls._wadd(b, url[k+5] << 8)
        if length > 4: b = cls._wadd(b, url[k+4])
        if length > 3: a = cls._wadd(a, url[k+3] << 24)
        if length > 2: a = cls._wadd(a, url[k+2] << 16)
        if length > 1: a = cls._wadd(a, url[k+1] << 8)
        if length > 0: a = cls._wadd(a, url[k])

        a, b, c = cls._mix(a, b, c);

        # integer is always positive
        return c

    @classmethod
    def _mix(cls, a, b, c):
        a = cls._wsub(a, b); a = cls._wsub(a, c); a ^= c >> 13;
        b = cls._wsub(b, c); b = cls._wsub(b, a); b ^= (a << 8) % 4294967296;
        c = cls._wsub(c, a); c = cls._wsub(c, b); c ^= b >>13;
        a = cls._wsub(a, b); a = cls._wsub(a, c); a ^= c >> 12;
        b = cls._wsub(b, c); b = cls._wsub(b, a); b ^= (a << 16) % 4294967296;
        c = cls._wsub(c, a); c = cls._wsub(c, b); c ^= b >> 5;
        a = cls._wsub(a, b); a = cls._wsub(a, c); a ^= c >> 3;
        b = cls._wsub(b, c); b = cls._wsub(b, a); b ^= (a << 10) % 4294967296;
        c = cls._wsub(c, a); c = cls._wsub(c, b); c ^= b >> 15;

        return a, b, c

    @staticmethod
    def _wadd(a, b):
        return (a + b) % 4294967296

    @staticmethod
    def _wsub(a, b):
        return (a - b) % 4294967296


if __name__ == "__main__":
    url = sys.argv[1]
    providers = (AlexaTrafficRank(), GooglePageRank(),)

    print("Traffic stats for: %s" % (url))
    for p in providers:
        print("%s:%d" % (p.__class__.__name__, p.get_rank(url)))

最佳答案

在您的两个 get_rank 实例方法中，您都有一行:

if response.getcode() == httplib.OK:

然后是另一个函数特定的 if。如果两者都评估为 True，这些方法只会返回一个值(另外，在 AlexaTrafficRank 中，element.iterfind("SD") 必须有值)；否则，它们将隐式返回 None，因此会出现您看到的错误。

关于Python 正在工作 - 没有做任何更改 - 将不再工作。可能发生了什么？，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/21970166/