fun with threads

fun.py

import time
import threading


def thing(key, value, queue, results):
    print(f"Processing {key=} {value=}")
    # what happens to the thread when there's an exception here?
    # the thread should catch it and remove the job from the queue so that
    # another can be enqueued.
    results[key] = value ** 2
    del queue[key]


def main():
    jobs = {}
    complete = {}

    tasks = {f"count{n}": n for n in [5, 10, 20, 30, 40, 60]}
    try:
        while True:
            print("------------------------------")
            print(f"CURRENT QUEUE: {len(jobs)}")
            print(f"Jobs: {jobs}")
            print(f"Results: {complete}")
            for key, value in tasks.items():
                try:
                    if jobs[key].is_alive():
                        # job still executing from last time
                        # do some kind of timeout?
                        # Maybe pass a start time to the thread, and compare
                        # with interval/refresh/end date.
                        print(f"JOB {key} ALREADY RUNNING")
                        continue
                except KeyError:
                    pass
                print(f"JOB {key} QUEUED")
                # This has to be run one time, before the while loop, with no timer
                # to prepopulate the data on boot
                jobs[key] = threading.Timer(
                    function=thing,
                    args=(key, value, jobs, complete),
                    interval=value,
                )
                jobs[key].daemon = True
                jobs[key].start()
            print("------------------------------")
            time.sleep(10)
    except KeyboardInterrupt:
        print("Gracefully exiting")
        exit(0)


if __name__ == "__main__":
    main()