I'm trying to execute my face detection function and use Apscheduler to run the function only between certain time. I can start the function correctly but the end_time parameter doesn't seem to work at all, the function just keeps on running until shutted down manually.
Here is the route which starts the schedule:
@app.route("/schedule/start", methods = ['POST'])
def create():
sched = BlockingScheduler()
sched.add_job(detection, 'cron', start_date='2020-10-01 15:33:00', end_date='2020-10-01 15:33:05')
sched.start()
return 'Schedule created.'
I have a While True condition in my detection -function, all the detetion logic run inside it. Could that be the reason why it never stops even if I have determined the stop time? How could I fix this issue?
Edit. While -loop from my detection -function (removed unnecessary parts):
while True:
frame = stream.read()
frame = imutils.resize(frame, width=900)
frame = cv2.cvtColor(frame, cv2.COLOR_BGR2GRAY)
frame = np.dstack([frame, frame, frame])
# frame = cv2.flip(frame, 0)
faces = faceCascade.detectMultiScale(
frame,
scaleFactor=1.1,
minNeighbors=3,
# minSize=(10, 10),
# maxSize=(50, 50),
# flags=cv2.CASCADE_SCALE_IMAGE
)
for (x, y, w, h) in faces:
name = str(currentframe) + '.jpg'
print('Creating...' + name)
cv2.imwrite(os.path.join(parent_dir, name), frame)
currentframe += 1
if cv2.waitKey(1) & 0xFF == ord('q'):
break
Edit2. I tried as suggested below and got this error: TypeError: func must be a callable or a textual reference to one.
I would also like to integrate a ability to manually start and stop my face detection function. I'm able to do it like this:
@app.route("/start", methods = ['POST'])
def start():
os.environ['run'] = 'running'
detection()
return 'Detection started'
@app.route("/stop", methods = ['POST'])
def stop():
os.environ['run'] = 'stop'
return 'Detection stopped.'
And then in my detection.py I just check the environment variable in the beginnig of my while-loop:
while True:
if os.environ.get('run') == 'stop':
stream.stream.release()
exit()
What I'd want would be to integrate the scheduling feature to this. I wouldn't want to have to make separate functions because I want to be able to manually stop the detection started with schedule. Any tips how I could achieve this?
Edit3. The schedule is working now. Manual start works also and stopping works in a mean that it stops detecting faces. The function started with schedule still keeps going though, it just doesn't iterate to the detection part at all because there is a os.environ['run'] = 'stop' -flag. Any idea how I could stop the function execution?
This is the while -loop check I have:
while True:
if self.end_date <= datetime.now() or os.environ.get('run') == 'stop':
stream.stream.release()
exit()
When manually started, the stop function works as supposed, but when stopping a scheduled job, it keeps looping until the end_date time is met.
You need to have some condition that will end your while loop as it's infinite now, pass start/end times and convert to date-time and try to match while end_date_time =< now: then quit the task. If you need to pass start/end dates, maybe convert the your detection function to class and on initialization pass the end_date when you want your cron job to stop.
# detection.py
from datetime import datetime
class Detection:
def __init__(self, end_date):
self.end_date = datetime.strptime(end_date, '%Y-%m-%d %H:%M:%S.%f')
def detection(self):
print(self.end_date)
while self.end_date <= datetime.utcnow():
print('works')
# routes.py
# And then do it like this when starting cron
import Detection
def create():
start_date = '2020-10-02 01:48:00.192386'
end_date = '2020-10-02 05:50:00.192386'
dt = Detection(end_date)
sched = BlockingScheduler()
sched.add_job(dt.detection, 'cron', start_date=start_date, end_date=end_date)
sched.start()
return 'Schedule created.'
This should resolve the issue