I’ve been working on getting redbeat setup & working with my Flask app but I cant seem to get it to start correctly. When I run the command

celery -A celery_config.celery beat --scheduler redbeat.RedBeatScheduler

I get this error originating from here which makes it seem like redis_url in conf is None

  File "/Users/test/Documents/Projects/Project/.venv/lib/python3.9/site-packages/redbeat/schedulers.py", line 401, in setup_schedule
    client = get_redis(self.app)
  File "/Users/test/Documents/Projects/Project/.venv/lib/python3.9/site-packages/redbeat/schedulers.py", line 124, in get_redis
    elif conf.redis_url.startswith('redis-sentinel') and 'sentinels' in redis_options:
AttributeError: 'NoneType' object has no attribute 'startswith'

I believe my setup has to be wrong somehow for this error to occur, but I’m not sure where/how. Any pointers/help is greatly appreciated to get this thing up and running. Here is some trimmed-down relevant code for how I’ve set it up & how I’m trying to use it.

application.py file where I create the Flask App and tie application.celery_app to the celery instance I create in the celery_config file

from flask import Flask, redirect, url_for
from extensions import ma, jwt, db, socketio
import config.const as CONSTANTS
from web.authentication import auth
from web.tasks import tasks
from flask_cors import CORS
from celery_config import init_celery

def create_app():
    application = Flask(__name__)
    configure_app(application)
    application.celery_app = init_celery(application)


    return application



def configure_app(application):
    application.config['SQLALCHEMY_DATABASE_URI'] = CONSTANTS.DB_CONNECTION_STRING
    application.config['SECRET_KEY'] = CONSTANTS.SECRET
    application.config['SQLALCHEMY_TRACK_MODIFICATIONS'] = False
    application.config['PREFERRED_URL_SCHEME'] = 'https'

application = create_app()



if __name__ == '__main__':
    application.run(debug=True, use_reloader=False, port=5009)

Here is celery_config.py where celery is created and configured. I’m running redis locally in a terminal window.

from celery import Celery

celery = None


def make_celery(app):
    app.config.update(
        CELERY_BROKER_URL='redis://localhost:6379/0',
        CELERY_RESULT_BACKEND='redis://localhost:6379/0',
        REDBEAT_REDIS_URL='redis://localhost:6379/1'
    )

    celery = Celery(app.import_name, broker=app.config['CELERY_BROKER_URL'])

    celery.conf.update({
        'beat_scheduler': 'redbeat.RedBeatScheduler',
        'beat_schedule': {},
        'redbeat_key_prefix': 'redbeat:',
        'redbeat_redis_url': app.config['REDBEAT_REDIS_URL']
    })

    return celery


def init_celery(app):
    global celery
    celery = make_celery(app)
    return celery

And lastly this is the file I would be adding, editing, and removing tasks. I’m guessing the error is coming from here where I create new entries using RedBeatSchedulerEntry()

from celery.schedules import crontab
from flask import Blueprint, jsonify, request
from models.task import Task
from services.login_decorator import duo_login_required
import services.helpers as helpers
from datetime import datetime, timedelta
from redbeat import RedBeatSchedulerEntry
from celery_config import celery as celery_app



tasks = Blueprint('tasks', __name__)


@tasks.route('/create_task', methods=['POST'])
def create_new_task():

    try:
        body = request.json
        task = Task()



        if body['interval'] == True:
            task.name = body['name']
            task.type = body['type']
            task.url = body['url']
            task.interval = True
            task.interval_time = body['time']
            task.update()
            key = task.id
            args = [task.id, task.url]

            schedule = timedelta(minutes=int(task.interval_time))
            entry = RedBeatSchedulerEntry(key, 'myapp.tasks.task_function', schedule, args=args, kwargs={},
                                          app=celery_app)
            entry.save()

            return jsonify({'id': task.id, 'name': task.name, 'type': task.type, 'interval_time': body['time'],'interval': True, 'url': task.url}), 200