python - 使用列表时的排序问题

Question

我有一个包含 IP 地址列表的 .txt 文件:

111.67.74.234:8080
111.67.75.89:8080
12.155.183.18:3128
128.208.04.198:2124
142.169.1.233:80 

不过还有很多:)

无论如何，使用 Python 将它导入到一个列表中，我试图让它对它们进行排序，但我遇到了麻烦。有人有什么想法吗？

编辑:好吧，因为那是含糊不清的，这就是我所拥有的。

f = open("/Users/jch5324/Python/Proxy/resources/data/list-proxy.txt", 'r+')
lines = [x.split() for x in f]
new_file = (sorted(lines, key=lambda x:x[:18]))

Answer 1

当您希望它们按数字排序时，您可能会通过 ascii 字符串比较('.' < '5' 等)对它们进行排序。尝试将它们转换为整数元组，然后排序:

def ipPortToTuple(string):
    """
        '12.34.5.678:910' -> (12,34,5,678,910)
    """
    ip,port = string.strip().split(':')
    return tuple(int(i) for i in ip.split('.')) + (port,)

with open('myfile.txt') as f:
    nonemptyLines = (line for line in f if line.strip()!='')
    sorted(nonemptyLines, key=ipPortToTuple)

---

编辑:您得到的 ValueError 是因为您的文本文件并不像您暗示的那样完全采用 #.#.#.#:# 格式。 (可能有注释或空行，但在这种情况下，错误会提示一行中包含多个“:”。)您可以使用调试技术来解决您的问题，方法是捕获异常并发出有用的信息调试数据:

def tryParseLines(lines):
    for line in lines:
        try:
            yield ipPortToTuple(line.strip())
        except Exception:
            if __debug__:
                print('line {} did not match #.#.#.#:# format'.format(repr(line)))

with open('myfile.txt') as f:
    sorted(tryParseLines(f))

---

我在上面有点马虎，因为它仍然允许一些无效的 IP 地址通过(例如#.#.#.#.#，或 257.-1.#.#)。下面是一个更彻底的解决方案，它允许您执行诸如将 IP 地址与 < 进行比较之类的操作。运算符，也使排序自然地工作:

#!/usr/bin/python3

import functools
import re

@functools.total_ordering
class Ipv4Port(object):
    regex = re.compile(r'(\d{1,3})\.(\d{1,3})\.(\d{1,3})\.(\d{1,3}):(\d{1,5})')

    def __init__(self, ipv4:(int,int,int,int), port:int):
        try:
            assert type(ipv4)==tuple and len(ipv4)==4, 'ipv4 not 4-length tuple'
            assert all(0<=x<256 for x in ipv4), 'ipv4 numbers not in valid range (0<=n<256)'
            assert type(port)==int, 'port must be integer'
        except AssertionError as ex:
            print('Invalid IPv4 input: ipv4={}, port={}'.format(repr(ipv4),repr(port)))
            raise ex

        self.ipv4 = ipv4
        self.port = port

        self._tuple = ipv4+(port,)

    @classmethod
    def fromString(cls, string:'12.34.5.678:910'):
        try:
            a,b,c,d,port = cls.regex.match(string.strip()).groups()
            ip = tuple(int(x) for x in (a,b,c,d))
            return cls(ip, int(port))
        except Exception as ex:
            args = list(ex.args) if ex.args else ['']
            args[0] += "\n...indicating ipv4 string {} doesn't match #.#.#.#:# format\n\n".format(repr(string))
            ex.args = tuple(args)
            raise ex

    def __lt__(self, other):
        return self._tuple < other._tuple
    def __eq__(self, other):
        return self._tuple == other._tuple

    def __repr__(self):
        #return 'Ipv4Port(ipv4={ipv4}, port={port})'.format(**self.__dict__)
        return "Ipv4Port.fromString('{}.{}.{}.{}:{}')".format(*self._tuple)

然后:

def tryParseLines(lines):
    for line in lines:
        line = line.strip()
        if line != '':
            try:
                yield Ipv4Port.fromString(line)
            except AssertionError as ex:
                raise ex
            except Exception as ex:
                if __debug__:
                    print(ex)
                raise ex

演示:

>>> lines = '222.111.22.44:214 \n222.1.1.1:234\n 23.1.35.6:199'.splitlines()
>>> sorted(tryParseLines(lines))
[Ipv4Port.fromString('23.1.35.6:199'), Ipv4Port.fromString('222.1.1.1:234'), Ipv4Port.fromString('222.111.22.44:214')]

将值更改为例如 264...或 ...-35...将导致相应的错误。