Progress Spinner Using Python Context Manager and Generators

spinner_ctxmanager.py

import sys
import time
from contextlib import contextmanager


def spinner_indicator(msg):
    ticks = ["-", "\\", "|", "/"]
    i = 0
    while True:
        tick = ticks[i % len(ticks)]
        yield sys.stdout.write(f"\r{tick} {msg}")
        i += 1


@contextmanager
def spinner(msg="working..."):
    error = False
    try:
        yield spinner_indicator(msg)
    except Exception:
        error = True
        raise
    except GeneratorExit:
        sys.stdout.write("\r✔\n")
    finally:
        if error:
            sys.stdout.write("\r𝘅\n")
        else:
            sys.stdout.write("\r✔\n")
        sys.stdout.flush()


if __name__ == "__main__":
    jobs = ["sample job", "another job", "job with an exception"]
    for job in jobs:
        with spinner(f"processing {job}...") as p:
            for i in range(10):
                next(p)
                time.sleep(0.25)
                if "exception" in job and i == 6:
                    raise ValueError("test exception")