aced

#!/usr/bin/env python3

import os
import os.path
import psutil
import signal
import subprocess
import time
import traceback

# stop service by raising a keyboard interrupt
def stop_service(signum, frame):
    raise KeyboardInterrupt()

# setup shutdown handler
signal.signal(signal.SIGTERM, stop_service)

# list containing all subprocesses store in reverse start order
subprocesses = []

try:
    # get installation directory
    saq_home = '/opt/ace'
    if 'SAQ_HOME' in os.environ:
        saq_home = os.environ['SAQ_HOME']

    # read list of commands to start from SAQ_HOME/etc/startupd
    startup_path = os.path.join(saq_home, "etc", "startupd")
    with open(startup_path, 'r') as f:
        commands = f.readlines()

    # get path to ace executable
    ace_path = os.path.join(saq_home, "ace")

    # start all listed commands
    for command in commands:
        # skip empty lines and comments
        command = command.strip()
        if command is None or command == "" or command.startswith("#"):
            continue

        engine, log_config = command.split()
        log_config_path = os.path.join("etc", log_config)

        # start the engine
        print("Starting {}".format(engine))
        p = subprocess.Popen(["python3", ace_path, "--start", "-L", log_config_path, engine])
        subprocesses.insert(0, psutil.Process(p.pid))

    # wait until told to stop by keyboard interrupt/sigterm
    while True:
        time.sleep(0.1)

# use keyboard interrupt as signal for shutdown
except KeyboardInterrupt:
    pass

# stop all subprocesses
for p in subprocesses:
    try:
        # ask process to stop gracefully
        p.terminate()

        # give the process some time to shutdown gracefully
        try:
            p.wait(timeout=60)

        # if the process did not shutdown gracefully in a reasonable amount of time then kill process tree
        except Exception:
            # kill all children
            for child in p.children(recursive=True):
                child.kill()

            # kill main process
            p.kill()

    except Exception as e:
        print("unable to stop process {}: {}".format(p, e))