log_monitor.py

import glob
import os
import time

disqualified_racers = set()
finished_racers = set()


def open_file():
    list_of_files = glob.glob("*.log")
    latest_file = max(list_of_files, key=os.path.getctime)
    print("Opened file: " + latest_file)
    return open(latest_file, "r+")


def follow(filename):
    filename.seek(0, 2)
    while True:
        line = filename.readline()
        if not line:
            time.sleep(0.1)
            continue
        yield line


def process(line):
    tokens = line.split()
    if len(tokens) != 3 and len(tokens) != 5:
        print("ERROR Bad line: " + line)
        print("Tokens: " + str(tokens))
        return

    if (
        tokens[3] == "disqualified"
        and tokens[4] == "1"
        and tokens[0] not in disqualified_racers
    ):
        disqualified_racers.add(tokens[0])
        handle_disqualified_racer(tokens[0])
        return

    if (
        tokens[3] == "finished"
        and tokens[4] == "1"
        and tokens[0] not in finished_racers
    ):
        finished_racers.add(tokens[0])
        handle_finished_racer(tokens[0])
        return

    if tokens[3] == "gates_passed":
        handle_gate_passed(tokens[0], tokens[4])


def handle_disqualified_racer(racer_name):
    print(racer_name + " has been disqualified!")
    # Start a new race.


def handle_finished_racer(racer_name):
    print(racer_name + " has finished!")
    # Start a new race.


def handle_gate_passed(racer_name, gate_idx_passed):
    # log file gate indices are 1-indexed, not 0-indexed
    print("{} passed gate idx {}".format(racer_name, gate_idx_passed - 1))


def main():
    f = open_file()
    for line in follow(f):
        process(line)


if __name__ == "__main__":
    main()