def replicate_files_on_change(
src_dir,
copy_file,
timeout=None,
use_gitignore=True,
debugging=False,
observer_up_event=None,
terminate_event=None,
):
"""Wait for changes to files in src_dir and copy with copy_file().
If provided, the timeout indicates when to return after that many seconds of no change.
"""
print("debug: replicate on change start")
src_dir = os.path.abspath(src_dir)
if use_gitignore:
spec = get_pathspec(src_dir, use_gitignore)
event_handler = GitIgnoreCopyFileEventHandler(copy_file,
spec,
debugging=debugging)
else:
event_handler = CopyFileEventHandler(copy_file, debugging=debugging)
observer = Observer()
observer.schedule(event_handler, src_dir, recursive=True)
if debugging:
print("Starting observer")
observer.start()
if observer_up_event is not None:
while not observer.is_alive():
pass
# wait for event listeners to settle
time.sleep(0.5)
observer_up_event.set()
print("notified observer up")
try:
while True:
time.sleep(0.5)
if timeout:
raise_if_timeout(event_handler.last_event_timestamp, timeout)
if terminate_event and terminate_event.is_set():
raise ConditionalTermination("Termination condition was set.")
except (KeyboardInterrupt, NoChangeTimeout, ConditionalTermination) as e:
if debugging:
print(f"Exitting on {type(e).__name__}: {e}")
finally:
now = time.time()
# still, dispatch the existing change events before we part ways
while time.time(
) - now < TAIL_TIMEOUT and not observer.event_queue.empty():
print("flushing events")
observer.dispatch_events(observer.event_queue, observer.timeout)
left = now + TAIL_TIMEOUT - time.time()
observer.stop()
observer.join(timeout=max(0, left))
print(f"debug: finished replicate on change with {left} left")
