python - 使用 TextFSM 在中继上查找允许的 VLAN

Question

我正在尝试为 NTC ansible 设置一个 TextFSM 模板，它只会从“show interface trunk”命令的输出中提取主干上允许的 Vlan，并且似乎无法得到我想要的。它给了我所有的行，而不仅仅是我想要的单行。该命令的输出如下所示：

switch#sh int g9/17 trunk

Port                Mode         Encapsulation  Status        Native vlan
Gi9/17              on           802.1q         trunking      1

Port                Vlans allowed on trunk
Gi9/17              501,503,513,540,950-957

Port                Vlans allowed and active in management domain
Gi9/17              501,503,513,540,950-957

Port                Vlans in spanning tree forwarding state and not pruned
Gi9/17              501,503,513,540,950-957

在此输出中，我只想返回“中继上允许的 Vlan”下方的行，而不是具有相同信息的其他重复行。我的模板如下所示：

Value PORT (\S+)
Value VLANS (.*)

Start
  ^Port.*Vlans allowed on trunk -> Begin

Begin
  ^(?=\s{0,9}${PORT})\s+${VLANS} -> Record
  ^Port.*Vlans allowed and active in management domain -> End

Answer 1

使正则表达式更具体并获得所需的结果（也许:)。

import io
import textfsm

template = io.StringIO("""\
Value Port (\S+(/\d+)?)
Value Vlans (\d+([-,]\d+)+)

Start
  ^Port\s+Vlans allowed on trunk$$ -> Begin

Begin
  ^${Port}\s+${Vlans}$$ -> Record
  ^Port\s+Vlans allowed and active in management domain$$ -> End
""")
fsm = textfsm.TextFSM(template)
result = fsm.ParseText("""\
switch#sh int g9/17 trunk

Port                Mode         Encapsulation  Status        Native vlan
Gi9/17              on           802.1q         trunking      1

Port                Vlans allowed on trunk
Gi9/17              501,503,513,540,950-957

Port                Vlans allowed and active in management domain
Gi9/17              501,503,513,540,950-957

Port                Vlans in spanning tree forwarding state and not pruned
Gi9/17              501,503,513,540,950-957
""")
print(result)

[['Gi9/17', '501,503,513,540,950-957']]