工作中需要对地址包含关系进行测试，现有ipaddress标准库和IPy无法满足，于是自己动手编写小脚本，主要实现== , in, <等专用功能，其他功能可以后续用到再补充，例如迭代打印网段内所有地址，输出前缀长度等等。
一，含有的类：
Host类：主机地址，eg, Host('192.168.1.1')
Network类：网络地址，eg，Network('192.168.1.0 255.255.255.0')
AddressGroup类：主机地址和网络地址组成的列表，eg，AddressGroup(['192.168.1.0 255.255.255.0', '10.1.1.1'])
二，实现的功能：
Host—>Network—>AddressGroup，低级别向高级别支持in测试
Network/AddressGroup同类之间支持<=测试
1)Host in Network，Host in AddressGroup测试
Host('192.168.1.1') in Network('192.168.1.0 255.255.255.0') # True
Host('192.12.1.5') in Network('192.0.1.0 255.0.255.0') # True，Network可以是通配符
Host('192.12.1.5') in AddressGroup(['192.168.1.0 255.255.255.0', '10.1.1.1']) # True
2)Network in AddressGroup测试
Network(192.168.1.0 255.255.255.0) in AddressGroup(['192.168.0.0 255.255.0.0', '10.1.1.1'])
3)Network <= Network测试
Network(192.168.1.0 255.255.255.0) <= Network('192.168.0.0 255.255.0.0') # True
Network(192.0.1.0 255.0.255.0) <= Network('192.168.0.0 255.255.0.0') # False，Network可以是通配符
4)AddressGroup <= AddressGroup测试
AddressGroup(['192.168.1.0 255.255.255.0', '10.1.1.1']) <= AddressGroup(['192.168.0.0 255.255.255.0', '10.1.1.1']) # True
5)前缀修正
n1 = Network('192.168.1.0 255.0.255.0')
n1.network # 192.0.1.0
三，由于数据源都是标准的地址格式，因此很多细节和出错控制未考虑：
Address('300.1000.2.1') # 未做地址或者网段的出错控制，仅控制了split('.')是否等于4以及元素是否是整数
AddressGroup含C类host明细时，与所属AddressGroup网段进行eq比较时会不等
class AddressValueError(ValueError):
"""A Value Error related to the netmask.""" def ip_address(address):
try:
return Host(address)
except AddressValueError:
pass try:
return Network(address)
except AddressValueError:
pass raise AddressValueError('Not a valid host or network address: {!r}'.format(address)) def _host_int_from_string(address):
octets = address.split('.')
if len(octets) != 4:
raise AddressValueError("Expected 4 octets in {!r}".format(address))
try:
return [int(i) for i in octets]
except ValueError as exc:
raise AddressValueError("%s in %r" % (exc, address)) from None def _network_int_from_string(address):
parts = address.split()
if len(parts) != 2:
raise AddressValueError("Expected network plus netmask in {!r}".format(address))
return _host_int_from_string(parts[0]), _host_int_from_string(parts[1]) class Host(object):
"""eg, address: 192.168.1.1"""
__slots__ = ('_address', '_host') def __init__(self, address):
self._address= address
self._host = _host_int_from_string(address) def __repr__(self):
return '<Host:{!r}>'.format(self._address) def __eq__(self, other):
try:
return self._address == other._address
except AttributeError:
return NotImplemented class Network(object):
"""eg, address: 192.168.1.0 255.255.255.0"""
__slots__ = ('_address', '_network', '_netmask') def __init__(self, address):
self._address = address
self._network, self._netmask = _network_int_from_string(address)
self._network = [i[0] & i[1] for i in zip(self._network, self._netmask)] def __contains__(self, other):
if isinstance(other, Host):
network_other = [i[0] & i[1] for i in zip(other._host, self._netmask)]
if self._network == network_other:
return True
return False def __eq__(self, other):
try:
return self._network == other._network and self._netmask == other._netmask
except AttributeError:
return NotImplemented def __le__(self, other):
if isinstance(other, Network):
parts = [i[0] & i[1] for i in zip(self._network, other._netmask)]
if parts == other._network and all([i[0] >= i[1] for i in zip(self._netmask, other._netmask)]):
return True
return False def __repr__(self):
return '<Network:{!r}>'.format(self._address) @property
def network(self):
return '.'.join([str(i) for i in self._network]) class AddressGroup(object):
""" eg,address_group: ['192.168.1.1', '192.168.1.2', '10.1.1.0 255.255.255.0']
无法继承abc.Set，因为abc.Set中两个Set长度相等直接返回Fasle，本类不一定，因此需要重构__lt__特殊方法 """
def __init__(self, components):
self._components = list(components)
self._compObjs = [ip_address(i) for i in components] def __len__(self):
return len(self._components) def __iter__(self):
for c in self._compObjs:
yield c def __contains__(self, other):
if isinstance(other, Host):
for obj in self:
cond1 = isinstance(obj, Host) and other == obj
cond2 = isinstance(obj, Network) and other in obj
if cond1 or cond2:
return True
if isinstance(other, Network):
for obj in self:
if isinstance(obj, Network) and other <= obj:
return True
return False def __eq__(self, other):
try:
return sorted(self._components) == sorted(other._components)
except AttributeError:
return NotImplemented def __lt__(self, other):
return all([i in other for i in self._compObjs]) def __repr__(self):
return '<AddressGroup:{!r}>'.format(' | '.join(self._components))