如何在python中解析CLI命令输出（表）？

Question

I am a newbie to parsing.

switch-630624 [standalone: master] (config) # show interface ib status

Interface      Description                                Speed                   Current line rate   Logical port state   Physical port state
---------      -----------                                ---------               -----------------   ------------------   -------------------
Ib 1/1                                                    14.0 Gbps rate          56.0 Gbps           Initialize           LinkUp
Ib 1/2                                                    14.0 Gbps rate          56.0 Gbps           Initialize           LinkUp
Ib 1/3                                                    2.5 Gbps rate only      10.0 Gbps           Down                 Polling

Assume I have an engine which injects the command on the switch, and put the above output as 1 huge string in a variable named "output".

I would like to return a dictionary which includes only the ports number as follows:

{'Ib1/11': '1/11', 'Ib1/10': '1/10', ... , }

I guess I should use the Python`s Subprocess module and regular expressions.

Number of ports can vary (can be 3, 10, 20, 30, 60...).

I will appreciate any kind of direction.

Thanks,

Qwerty

Answer 1

# Did this in Python 2.7
import re

# Assume your input is in this file
INPUT_FILE = 'text.txt'

# Regex to only pay attention to lines starting with Ib
# and capture the port info
regex = re.compile(r'^(Ib\s*\S+)')
result = [] # Store results in a list
with open(INPUT_FILE, 'r') as theFile:
  for line in theFile:
    match = regex.search(line)
    if not match: continue
    result.append(match.group())
print result