Netfilter to json

#!/usr/bin/env python3
# -*- coding: utf-8 -*-
"""
Created on Sun Jul 18 11:12:29 2021

@author: mf18626
"""
import os
import sys
import json

def readLogFile(logFile):
    try:
        with open(logFile) as f:
            logLines = f.readlines()
        return logLines
    except FileNotFoundError:
        print("No such file")
        return None

def parse(logLine):

    keywords = ["in=","out=","src=","dst=","proto=","spt=","dpt=","ack","syn","psh","fin","rst"]
    tokenizedLogLine = logLine.split()

    # Inizializzo i campi, che saranno comuni a tutti i protocolli; poi qualcuno li popola, qualcuno no
    fields={"timestamp":"",
            "eventId":"",
            "inIface":"",
            "outIface":"",
            "srcIP":"",
            "dstIP":"",
            "spt":"",
            "dpt":"",
            "proto":"",
            "syn":"",
            "ack":"",
            "psh":"",
            "fin":"",
            "rst":""}
    # Il timestamp è sempre al primo posto
    fields.update({"timestamp":tokenizedLogLine[0]})
    # Utilizzo sempre il quarto campo come identificatore per poi ordinare su elastic
    fields.update({"eventId":tokenizedLogLine[3]})

    for token in tokenizedLogLine:
        for keyword in keywords:
            for token in tokenizedLogLine:
                if keyword.lower() in token.lower():
                    if keyword == "in=":
                        fields.update({"inIface":token.lower().split("=")[1]})
                    elif keyword == "out=":
                        fields.update({"outIface":token.lower().split("=")[1]})
                    elif keyword =="src=":
                        fields.update({"srcIP":token.lower().split("=")[1]})
                    elif keyword =="dst=":
                        fields.update({"dstIP":token.lower().split("=")[1]})
                    elif keyword =="proto=":
                        fields.update({"proto":token.lower().split("=")[1]})
                    elif keyword =="spt=":
                        fields.update({"spt":token.lower().split("=")[1]})
                    elif keyword =="dpt=":
                        fields.update({"dpt":token.lower().split("=")[1]})
                    elif keyword =="syn":
                        fields.update({"syn":token.lower()})
                    elif keyword =="ack":
                        fields.update({"ack":token.lower()})
                    elif keyword =="psh":
                        fields.update({"psh":token.lower()})
                    elif keyword =="fin":
                        fields.update({"fin":token.lower()})
                    elif keyword =="rst":
                        fields.update({"rst":token.lower()})
    return fields

logFileArray = readLogFile("campionato.log")
i = 0
for logLine in logFileArray:
    with open("input/jsonizedlog-"+str(i)+".json","w") as jsonfile:
        json.dump(parse(logLine),jsonfile)
    i += 1