Calling APscheduler during flask initiation /u/deepbuzz7 Python Education

Hi Everyone,

Asked this same question in r/flask as well

I am using apscheduler inside my flask application.

Note: I am not using Flask–APScheduler(flask extension). I am using its standalone library(pip install APScheduler)

========Let me give the context of my application ======================

i am starting my scheduler in create_app() function in application/__init__.py file. My code looks something like this

inside statusPollingScheduler.py file

def getStatusUpdatePollingScheduler(): executors={ 'default':ThreadPoolExecutor(1) } scheduler = BackgroundScheduler(executors=executors) scheduler.add_job( controllerThread, 'interval', seconds=15, max_instances=1, coalesce=True, args=(60,) #(timeout,) ) return scheduler 

inside application/__init__.py file

def startPollingScheduler(): from .statusPollingScheduler import getStatusUpdatePollingScheduler sch=getStatusUpdatePollingScheduler() try: sch.start() applogger.info("Polling scheduler started at flask instance initiation") except Exception as e: applogger.error(f"Polling scheduler failed to start. Exception - {e}") def create_app(): app=Flask(__name__) applogger.info("Flask instance initiated") startPollingScheduler() return app 

FYI i am running the flask with below code in main.py outside the application module

from application import create_app app=create_app() if __name__=='__main__': app.run() 

=================MY ISSUE ===================

When I check the logs I see that Flask instance initiated and Polling scheduler started at flask instance initiation getting logged multiple times. Seems like my flask instance is getting restarted again and again as long as the apscheduler process is running. Now this is only happenning when I bring APscheduler in the picture. When I comment out the startPollingScheduler() function, flask does not get restarted repeateadly. I want to know the reason behind this.

Thanks

Hi Everyone,

Asked this same question in r/flask as well

I am using apscheduler inside my flask application.

Note: I am not using Flask–APScheduler(flask extension). I am using its standalone library(pip install APScheduler)

========Let me give the context of my application ======================

i am starting my scheduler in create_app() function in application/__init__.py file. My code looks something like this

inside statusPollingScheduler.py file

def getStatusUpdatePollingScheduler(): executors={ 'default':ThreadPoolExecutor(1) } scheduler = BackgroundScheduler(executors=executors) scheduler.add_job( controllerThread, 'interval', seconds=15, max_instances=1, coalesce=True, args=(60,) #(timeout,) ) return scheduler 

inside application/__init__.py file

def startPollingScheduler(): from .statusPollingScheduler import getStatusUpdatePollingScheduler sch=getStatusUpdatePollingScheduler() try: sch.start() applogger.info("Polling scheduler started at flask instance initiation") except Exception as e: applogger.error(f"Polling scheduler failed to start. Exception - {e}") def create_app(): app=Flask(__name__) applogger.info("Flask instance initiated") startPollingScheduler() return app 

FYI i am running the flask with below code in main.py outside the application module

from application import create_app app=create_app() if __name__=='__main__': app.run() 

=================MY ISSUE ===================

When I check the logs I see that Flask instance initiated and Polling scheduler started at flask instance initiation getting logged multiple times. Seems like my flask instance is getting restarted again and again as long as the apscheduler process is running. Now this is only happenning when I bring APscheduler in the picture. When I comment out the startPollingScheduler() function, flask does not get restarted repeateadly. I want to know the reason behind this.

Thanks