rewrite worker to run on celery and redis

app/app.py

@@ -8,9 +8,10 @@ from misc import datetime, date, time, currDay, prevDay, ZoneInfo, currVersion,
 from db import (db, Period, Task, Event, User)
 from sqlalchemy import inspect
 from forms import (TaskForm, EventForm, PeriodForm, SignupForm, LoginForm, SettingsForm)
-from create_events import createEvents
 from log import appLogger
 
+from worker import runCreateEvents
+
 # init logger
 logger = appLogger('app')
 
@@ -183,7 +184,7 @@ def newPeriod():
         db.session.commit()
         logger.info(f'New period added by \'{current_user.userName}\' from {sourceIP}')
         # Run createEvents upon adding new period
-        createEvents(db, currDay, Period, Event)
+        runCreateEvents()
         return redirect(f'/period/edit/{period.period}')
     return render_template('newPeriod.html', form=form)
 

app/requirements.txt

@@ -26,6 +26,10 @@ WTForms-SQLAlchemy==0.3.0
 # APScheduler automated scheduler
 APScheduler==3.10.1
 
+# Celery Task Queue
+celery[redis]==5.2.7
+redis==4.5.4
+
 # Python Time packages
 pytz==2022.7.1
 

app/worker.py

@@ -1,9 +1,10 @@
+from celery import Celery
+from celery.schedules import crontab
+from create_events import createEvents
 import os
 from flask import Flask
 from misc import currDay, datetime, time, timedelta
 from db import db, Period, Event
-from create_events import createEvents
-from apscheduler.schedulers.background import BlockingScheduler
 
 basedir = os.path.abspath(os.path.dirname(__file__))
 
@@ -18,18 +19,24 @@ app.config['SQLALCHEMY_DATABASE_URI'] =\
 app.config['SQLALCHEMY_TRACK_MODIFICATIONS'] = False
 db.init_app(app)
 
-# Define function to run create_events with app context
-def run_create_events():
+redis_url = 'redis://' + \
+            os.environ['REDIS_HOST'] + \
+            ':' + os.environ['REDIS_PORT'] + \
+            '/' + os.environ['REDIS_DBNUM']
+
+celerymsg = Celery('tasks', backend=redis_url, broker=redis_url)
+
+# Task definitions
+@celerymsg.task
+def runCreateEvents():
     with app.app_context():
         createEvents(db, currDay, Period, Event)
 
-# Call createEvents on initial launch of the script
-run_create_events()
-
-
-# Set up scheduler to run function at 59th minute of every hour
-scheduler = BlockingScheduler()
-scheduler.add_job(run_create_events, 'cron', minute=59)
-
-# Start scheduler
-scheduler.start()
+# Scheduled tasks
+celerymsg.conf.beat_schedule = {
+    'hourly-createevents': {
+        'task': 'worker.runCreateEvents',
+        # Run hourly
+        'schedule': crontab(hour="*"),
+    }
+}