config.py 文件源码

def follow_config(path, poll_interval=1.0, force_interval=30.0):
    last_reload = -float("inf")
    last_mtime = None
    last_error_msg = None

    abspath = os.path.abspath(path)
    while True:
        now = time.time()
        if now < last_reload:
            last_reload = now

        mtime = os.path.getmtime(abspath)
        if now > last_reload + force_interval or last_mtime != mtime:
            try:
                configs = load_configs(abspath)
            except Exception:
                _, exc_value, exc_tb = sys.exc_info()

                stack = traceback.extract_tb(exc_tb)
                stack = stack[1:]  # Make the traceback flatter by discarding the current stack frame

                error_msg = "Could not load {path!r} (most recent call last):\n{stack}\n{exception}".format(
                    path=abspath,
                    stack="".join(traceback.format_list(stack)).rstrip(),
                    exception=utils.format_exception(exc_value)
                )

                if error_msg != last_error_msg:
                    yield idiokit.send(False, error_msg)
                    last_error_msg = error_msg
                    last_mtime = None
            else:
                yield idiokit.send(True, configs)
                last_error_msg = None
                last_mtime = mtime
                last_reload = now
        yield idiokit.sleep(poll_interval)