Python script to wait db connection for docker-compose

wait-db.py

#!/usr/bin/env python
import socket
import time
import os

if __name__ == '__main__':
    port = int(os.environ["DB_PORT"]) # 5432
    host = os.environ["DB_HOST"] # db
    s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    while True:
        try:
            s.connect((host, port))
            s.close()
            break
        except socket.error as ex:
            time.sleep(1)