Start and Stop a periodically background Task with Django - django

Question

I would like to make a bitcoin notification with Django. If managed to have a working Telegram bot that send the bitcoin stat when I ask him to do so. Now I would like him to send me a message if bitcoin reaches a specific value. There are some tutorials with running python script on server but not with Django. I read some answers and descriptions about django channels but couldn't adapt them to my project.
I would like to send, by telegram, a command about the amount and duration. Django would then start a process with these values and values of the channel I'm sending from in the background. If now, within the duration, the amount is reached, Django sends a message back to my channel. This should also be possible for more than one person.
Is these possible to do with Django out of the box, maybe with decorators, or do I need django-channels or something else?
Edit 2018-08-10:
Maybe my code explains a little bit better what I want to do.
import requests
import json
from datetime import datetime
from django.shortcuts import render
from django.http import HttpResponse
from django.conf import settings
from django.views.generic import TemplateView
from django.views.decorators.csrf
import csrf_exempt
class AboutView(TemplateView):
template_name = 'telapi/about.html'
bot_token = settings.BOT_TOKEN
def get_url(method):
return 'https://api.telegram.org/bot{}/{}'.format(bot_token, method)
def process_message(update):
data = {}
data['chat_id'] = update['message']['from']['id']
data['text'] = "I can hear you!"
r = requests.post(get_url('sendMessage'), data=data)
#csrf_exempt
def process_update(request, r_bot_token):
''' Method that is called from telegram-bot'''
if request.method == 'POST' and r_bot_token == bot_token:
update = json.loads(request.body.decode('utf-8'))
if 'message' in update:
if update['message']['text'] == 'give me news':
new_bitcoin_price(update)
else:
process_message(update)
return HttpResponse(status=200)
bitconin_api_uri = 'https://api.coinmarketcap.com/v2/ticker/1/?convert=EUR'
# response = requests.get(bitconin_api_uri)
def get_latest_bitcoin_price():
response = requests.get(bitconin_api_uri)
response_json = response.json()
euro_price = float(response_json['data']['quotes']['EUR']['price'])
timestamp = int(response_json['metadata']['timestamp'])
date = datetime.fromtimestamp(timestamp).strftime('%Y-%m-%d %H:%M:%S')
return euro_price, date
def new_bitcoin_price(update):
data = {}
data['chat_id'] = update['message']['from']['id']
euro_price, date = get_latest_bitcoin_price()
data['text'] = "Aktuel ({}) beträgt der Preis {:.2f}€".format(
date, euro_price)
r = requests.post(get_url('sendMessage'), data=data)
Edit 2018-08-13:
I think the solution would be celery-beat and channels. Does anyone know a good tutorial?

Answer 1

One of my teammates uses django-celery-beat, that is available at https://github.com/celery/django-celery-beat to do this and he gave me some excellent feedback from it. You can schedule the celery tasks using the crontab syntax.

Answer 2

I had same issue, there are several typical approaches: Celery, Django-Channels, etc.
But you can avoid them all with simple approach: https://docs.djangoproject.com/en/2.1/howto/custom-management-commands/
I have used django commands in my project to run periodically tasks to rebuild users statistics:
Implement yourself application command, for example your application name is myapp and you have placed my_periodic_task.py in myapp/management/commands folder, so you can run your task once by typing python manage.py my_periodic_task
place beside manage.py file new file for example background.py with same code:
-
import os
from subprocess import call
BASE = os.path.dirname(__file__)
MANAGE_BASE = os.path.join(BASE, 'manage.py')
while True:
sleep(YOUR_TIMEOUT)
call(['python', MANAGE_BASE , 'my_periodic_task'])
Run your server for example: python background.py & python manage.py runserver 0.0.0.0:8000