ftail/ftail.py

import argparse
from console_bottombar import BottomBar
import os
import re
import sys
import tail
import task

VERSION = "0.1.0"

HELPTEXT = """
F1: Get this help message
F2: Set a filter (regular expression) for the topic of a message
    Examples:
    * "/gfw/.*/main_light/" to get everything with "/gfw/" before "/main_light/"
    * "^zigbee.*(?>!logging)$" to get everything starting with "zigbee" and not ending with "logging"
    * "^(?!shellies).*/dirk/.*temperature$" to get everything not starting with "shellies" followed by "/dirk/" and ends with "temperature"
F12: Quit ftail

'c': Clear screen
'q': Quit
"""


def tail_parser(line):
    global my_bb

    try:
        match = len(re.findall(my_bb.get_entry('msg_re'), line)) > 0
    except re.error:
        print('No valid regular expression (%s). No filter active.' % my_bb.get_entry('msg_re'))
        match = True

    if match:
        sys.stdout.write(line)


if __name__ == "__main__":
    parser = argparse.ArgumentParser(description='This is a mqtt sniffer.')
    parser.add_argument('logfile')  # , nargs='+' for >= 1

    args = parser.parse_args()


    if not os.access(args.logfile, os.R_OK):
        print("Error: File %s is not readable!" % logfile)
        sys.exit(1)
    else:

        #
        # Background tail task
        #
        tp = tail.Tail(args.logfile)
        tp.register_callback(tail_parser)
        my_tail = task.delayed(0.1, tp.follow, 0.1)

        #
        # Bottombar
        #
        my_bb = BottomBar(VERSION, label='ftail')
        my_bb.add_entry('help', 1, my_bb.FUNC_INFO, '[F1] Help', infotext=HELPTEXT)
        my_bb.add_entry('msg_re', 2, my_bb.FUNC_TEXT, label='[F2] Filter', default="")
        my_bb.add_entry('quit', 12, my_bb.FUNC_QUIT, "Quit", label='[F12]', right=True)

        my_tail.run()
        my_bb.run()

        my_tail.stop()