多重行上的正则表达式\n

Question

在下面的代码中，我想捕获实例ID，然后捕获它下面的主体。这种模式是反复出现的，因此有多个具有相同主体的实例。我似乎想不出如何让它继续通过换行符段。

import re

config = '''
Instance: evpn-a

VLAN ID: 123, MAC address: 00:05:86:71:05:f0
  Source: irb.0, Rank: 1, Status: Active
    State: <Local-MAC-Only Local-Gateway Remote-Adv-Allowed>
    IP address: 192.168.10.251

VLAN ID: 123, MAC address: 00:05:86:71:ab:f0
  Source: 20.1.1.2, Rank: 1, Status: Active
    State: <Remote-Gateway Local-Adv-Allowed Local-Adv-Done>
    IP address: 192.168.10.252
      L3 route: 192.168.10.252/32, L3 context: bridge-vrf (irb.0)

Instance: evpn-b

VLAN ID: 123, MAC address: 00:05:86:71:05:f0
  Source: irb.0, Rank: 1, Status: Active
    State: <Local-MAC-Only Local-Gateway Remote-Adv-Allowed>
    IP address: 192.168.10.251

VLAN ID: 123, MAC address: 00:05:86:71:ab:f0
  Source: 20.1.1.2, Rank: 1, Status: Active
    State: <Remote-Gateway Local-Adv-Allowed Local-Adv-Done>
    IP address: 192.168.10.252
      L3 route: 192.168.10.252/32, L3 context: bridge-vrf (irb.0)
'''


evpn_obj_list = re.compile(r'Instance:\s+(\S+)(.*?)(?:\S+|\Z)',re.S|re.M).findall(config)

evpn = evpn_obj_list

print(evpn)

我从上面得到的结果是：

[('evpn-a', '\n\n'), ('evpn-b', '\n\n')]

Answer 1

你可以用

rx = re.compile(r'^Instance:\s+(\S+)\s*(.*?)(?=\n\s*Instance:\s|\Z)', re.S|re.M)
evpn_obj_list = rx.findall(config)

见regex演示。

详细信息

• ^ -行的开始
• Instance: -字符串
• \s+ - 1+白空间
• (\S+) - Group 1:任意一个或多个非空白字符
• \s* - 0+白空间
• (.*?) -第2组:任意0或多个字符，尽可能少
• (?=\n\s*Instance:\s|\Z) --一个积极的前瞻性，它需要一个换行符、0+空格、Instance:、一个空格或文件的末尾紧靠在当前位置的右边。

见Python演示屈服

[('evpn-a', 'VLAN ID: 123, MAC address: 00:05:86:71:05:f0\n  Source: irb.0, Rank: 1, Status: Active\n    State: <Local-MAC-Only Local-Gateway Remote-Adv-Allowed>\n    IP address: 192.168.10.251\n\nVLAN ID: 123, MAC address: 00:05:86:71:ab:f0\n  Source: 20.1.1.2, Rank: 1, Status: Active\n    State: <Remote-Gateway Local-Adv-Allowed Local-Adv-Done>\n    IP address: 192.168.10.252\n      L3 route: 192.168.10.252/32, L3 context: bridge-vrf (irb.0)'), ('evpn-b', 'VLAN ID: 123, MAC address: 00:05:86:71:05:f0\n  Source: irb.0, Rank: 1, Status: Active\n    State: <Local-MAC-Only Local-Gateway Remote-Adv-Allowed>\n    IP address: 192.168.10.251\n\nVLAN ID: 123, MAC address: 00:05:86:71:ab:f0\n  Source: 20.1.1.2, Rank: 1, Status: Active\n    State: <Remote-Gateway Local-Adv-Allowed Local-Adv-Done>\n    IP address: 192.168.10.252\n      L3 route: 192.168.10.252/32, L3 context: bridge-vrf (irb.0)\n')]