#!/usr/bin/env python3
# coding: utf-8

import socket
import argparse
import time
import sys


def tcp_ping(port, timeout):
    now = time.time()
    while time.time() - now < timeout:
        try:
            with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as sock:
                sock.connect(("0.0.0.0", port))
                print(f"OK :{port} is listening")
                sys.stdout.flush()
                return
        except Exception:
            print(f"... connecting to :{port}")
            sys.stdout.flush()
            time.sleep(1)
    raise Exception(f"failed connecting to :{port}")


if __name__ == "__main__":
    parser = argparse.ArgumentParser(
        description="block until successfully connected to a local tcp port"
    )
    parser.add_argument("-p", "--port", type=int, help="local tcp port")
    parser.add_argument("-t", "--timeout", type=int, default=10, help="time to wait.")
    args = parser.parse_args()
    tcp_ping(args.port, args.timeout)