Sort and tabulate the output of ovs-ofctl dump-flows

ovs-sort-flows.py

'''
Make the output of ovs-ofctl dump-flows more readable
'''
import re
import sys
from tabulate import tabulate

PAT = re.compile("^ cookie.*table=(\d+), n_packets=(\d+).+ priority=(\d+),*(.*) actions=(.+)")

if len(sys.argv) == 2:
    flows_file = sys.argv[1]
else:
    print("Usage: python ovs-sort-flows.py /tmp/dump-flows.txt")
    sys.exit()


rows = []
with open(flows_file) as f:
    for line in f.readlines():
        m = re.match(PAT, line)
        if not m:
            continue
        priority = m.group(3)
        table = m.group(1)
        n_packets = m.group(2)
        match = m.group(4)
        actions = m.group(5)
        rows.append((int(table), int(priority), n_packets, match, actions))

# sort by table asending and then priority descending 
rows.sort(key=lambda k: (k[0],-k[1]))

headers = ['T', 'P', 'Packets', 'Match', 'Actions']
print(tabulate(rows, headers))