I want to update a value every day at a certain time later.
I wrote my models and views look like
models.py
class InvestmentRequest(models.Model):
user = models.OneToOneField(User, related_name=“investment_request”, on_delete=models.CASCADE)
profit = models.DecimalField(max_digits=15, decimal_places=2)
created_at = models.DateTimeField(auto_now_add=True)
def __str__(self):
return f"{self.user.username}-{self.amount}"
def increase_balance(self, profit ):
self.profit += decimal.Decimal(profit )
self.save()
def save(self, *args, **kwargs):
super().save(*args, **kwargs)
views.py
from apscheduler.schedulers.background import BackgroundScheduler
def roi_profit(request):
investment = InvestmentRequest.objects.get(user=request.user)
amount = 15
investment .increase_balance(amount)
return …
scheduler = BackgroundScheduler()
job = None
def tick():
print(‘One tick!’)
# roi_profit() --- any way like this
def start_job():
global job
job = scheduler.add_job(tick, 'interval', seconds=3)
try:
scheduler.start()
except:
pass
I used here “appscheduler” library because my requirement is minimal, it’s not a complex configuration like celery.
Is there any way to run ‘roi_profit’ views at a certain time every day? Here ‘tick’ function runs very smoothly because it is a normal function. But I can’t call the views function because it’s a required request. And without request, I can’t get any value from request.user. It’s necessary. So this way how I can update my model value at a certain time later every day. Over a couple of days I’m struggling with it but couldn’t find the exact solution.
Any suggestions will be appreciated. Thanks.
I am currently building a geolocation app, and I'm somewhat stuck somewhere. I'm trying to implement a post_save Django signals in this code, but I can't figure out what exactly I need to do. any help here would be appreciate. Here's my code:
from ipaddress import ip_address
from django.contrib.auth import get_user_model
from celery import shared_task
from apps.users.abstractapi import AbstractAPI
User = get_user_model()
#shared_task
def enrich_user(user_pk):
user = User.objects.get(pk=user_pk)
api = AbstractAPI()
location_details = api.get_geolocation_details(ip_address=user.ip_address)
if location_details is not None:
user.country = location_details.get("country")
user.country_code = location_details.get("country_code")
user.country_geoname_id = location_details.details.get("country_geoname_id")
user.longitude = location_details.get("longitude")
user.latitude = location_details.get("latitude")
user.save(update_fields=("country", "country_code", "country_geoname_id", "longitude", "latitude"))
holiday_details = api.get_holiday_details(
country_code=user.country_code,
day=user.date_joined.day,
month=user.date_joined.month,
year=user.date_joined.year,
)
if holiday_details is not None and any(holiday_details):
user.joined_on_holiday = True
user.save(update_fields=("joined_on_holiday",))
A post_save signal in Django looks like this:
from django.dispatch import receiver
#receiver(models.signals.post_save, sender=User)
def your_function(sender, instance, using, **kwargs):
# your code that you want to run
instance.save()
Be careful with saving the instance - that will itself cause the post_save signal to run again. You should put a condition in place that will only evaluate once before the instance is saved. Something like:
if instance.joined_on_holiday == False:
instance.joined_on_holiday = True
instance.save()
I'm trying to make a celery task that would send a basic reminder to our users. So in our automated communication project, we have these tasks:
As you can see there are few actions that are different. So for now I have created a logic that fetches all the users from the DB and then continues by checking the time difference. But for now, I only have set-up for 2 hours or more. How should I use it correctly? I do not want to re-write each if statement because it's bad practice. How should I make it clear and reduce the system load?
#app.task
def check_registered_users():
from apps.users.models import User
from apps.notifications.models import AutomatedCommunicationNotifications
day_start = datetime.utcnow().date()
day_end = day_start + timedelta(days=1)
users = User.objects.filter(is_active=True, date_joined__range=(day_start, day_end))
users_that_received_notification = AutomatedCommunicationNotifications.objects.all().values('user__id')
excluded_users = users.exclude(id__in=users_that_received_notification)
for user in excluded_users:
if user.last_login < user.last_login + timedelta(hours=2):
# Sign-up uncompleted Push notification 2 hours after last login
template = SiteConfiguration.get_solo().automated_comms_signup_uncompleted
send_plain_email_task(
email=user.email,
subject=template.subject,
html_message=template.content,
from_email=f'{settings.EMAIL_FROM_PREFIX} <{settings.DEFAULT_FROM_EMAIL}>',
)
P.S AutomatedCommunicationNotifications table is for us to track which user has already received a notification.
class AutomatedCommunicationNotifications(BaseModel):
""" Model for automated comms notifications """
user = models.ForeignKey(User, on_delete=models.CASCADE)
type = models.CharField(
max_length=255,
choices=NotificationTypes.get_choices(),
default=NotificationTypes.EMAIL_NOTIFICATION
)
def __str__(self):
return str(self.user.phone)
You'll have to iterate over your queried users at least once but here are tips that may help:
models.py
class User(...):
# add a field to determine if the user has registered or not
# set this to `True` when a User successfully registers:
is_registered = models.BooleanField(default=False)
class AutomatedCommunicationNotifications(BaseModel):
# add a related name field for easier coding:
user = models.ForeignKey(..., related_name = 'notifications')
tasks.py
# load packages outside of your function so this only runs once on startup:
from django.models import F
from apps.users.models import User
from apps.notifications.models import AutomatedCommunicationNotifications
#app.task
def check_registered_users():
# timestamps:
two_hours_ago = datetime.now() - timedelta(hours=2)
# query for unregistered users who have not received a notification:
users = User.objects.filter(
is_registered = False,
last_login__lt = two_hours_ago # last logged in 2 or more hours ago
).exclude(
notifications__type = "the type"
).prefetch_related(
'notifications' # prejoins tables to improve performance
)
for user in users:
# send email
...
I would do this with a cron job. You can let it run whenever you want, depends on how fast after your give time frame you want to sent this.
You start with making a folder in your app:
/django/yourapp/management/commands
There you make a python file which contains your logic. Make sure to import the right modules from your views.
from django.core.management.base import BaseCommand, CommandError
from yourapp.models import every, module, you, need
from django.utils import timezone
from datetime import datetime, date, timedelta
from django.core.mail import send_mail, EmailMessage
class Command(BaseCommand):
help = 'YOUR HELP TEXT FOR INTERNAL USE'
def handle(self, *args, **options):
# Your logic
I added the crontab to the www-data users crontab like this:
# m h dom mon dow command
45 3 * * * /websites/vaccinatieplanner/venv/bin/python /websites/vaccinatieplanner/manage.py reminder
You can use that crontab file to tweak your optimal time between checks. If you remove the 3 and replace it by a * then you will have it check every 45 mins.
I would like to get the absolute url from my saved object. My model has a method named get_absolute_url and I would like to call this method with my django post_save signal.
I receive a post_save signal when a new entry is added inside a specific table named Thread. This post_save signal executes my Celery task.
My Thread model is :
class Thread(models.Model):
""" A thread with a title """
topic = models.ForeignKey('Topic')
title = models.CharField(max_length=200)
sticky = models.BooleanField(default=False)
slug = models.SlugField()
time_created = models.DateTimeField(default=timezone.now)
time_last_activity = models.DateTimeField(default=timezone.now)
def __init__(self, *args, **kwargs):
""" Initialize 'time_last_activity' to 'time_created' """
super(Thread, self).__init__(*args, **kwargs)
self.time_last_activity = self.time_created
def __str__(self):
""" Return the thread's title """
return self.title
def get_absolute_url(self):
""" Return the url of the instance's detail view """
url_kwargs = {
'topic_pk': self.topic.pk,
'topic_slug': self.topic.slug,
'thread_pk': self.pk,
'thread_slug': self.slug,
}
return reverse('simple-forums:thread-detail', kwargs=url_kwargs)
In my model, I have a celery.py file :
# -*- coding: utf-8 -*-
from __future__ import unicode_literals
from django.db.models.signals import post_save
from django.dispatch import receiver
from simple_forums.models import Thread
from ..tasks import thread_notification
#receiver(post_save, sender=Thread)
def get_new_thread(sender, instance, **kwargs):
""" Post_save method which start Celery task to notify forum subscribers that a new thread has been created """
url = Thread.get_absolute_url()
print(url)
thread_title = instance.title
thread_id = instance.id
topic_id = instance.topic_id
topic_slug = instance.topic.slug
topic_title = instance.topic.title
thread_notification.delay(thread_id=thread_id, thread_title=thread_title, topic_id=topic_id, topic_slug=topic_slug,
topic_title=topic_title)
And in my tasks.py file :
# -*- coding: utf-8 -*-
from celery import shared_task
from django.contrib.auth import get_user_model
from django.utils.translation import ugettext_lazy as _
User = get_user_model()
#shared_task(bind=True, time_limit=3600, soft_time_limit=3600)
def thread_notification(self):
print('Celery task executed')
return ['success_message', _('Celery task ended')]
I would like to get the absolute_url in order to send an email with the new Thread path.
My question is : How I can pick up get_absolute_url or use request.build_absolute_uri if I don't have a specific view (not necessary) ?
Here:
#receiver(post_save, sender=Thread)
def get_new_thread(sender, instance, **kwargs):
url = Thread.get_absolute_url()
the saved Thread instance is (suprise, surprise) your instance argument, so you want:
url = instance.get_absolute_url()
calling an instance method on a class makes no sense (nb: except for a couple specific corner cases, and then you have to pass the instance as first argument, but let's not get further with this, when you'll need it you'll know how it works).
Now since you're in the same app, using a signal here makes no sense either and is actually an antipattern. The point of signals is to allow an app to react to events emitted by other apps. Here, your code should quite simply be in Thread.save().
I have done the below post_save signal in my project.
from django.db.models.signals import post_save
from django.contrib.auth.models import User
# CORE - SIGNALS
# Core Signals will operate based on post
def after_save_handler_attr_audit_obj(sender, **kwargs):
print User.get_profile()
if hasattr(kwargs['instance'], 'audit_obj'):
if kwargs['created']:
kwargs['instance'].audit_obj.create(operation="INSERT", operation_by=**USER.ID**).save()
else:
kwargs['instance'].audit_obj.create(operation="UPDATE").save()
# Connect the handler with the post save signal - Django 1.2
post_save.connect(after_save_handler_attr_audit_obj, dispatch_uid="core.models.audit.new")
The operation_by column, I want to get the user_id and store it. Any idea how can do that?
Can't be done. The current user is only available via the request, which is not available when using purely model functionality. Access the user in the view somehow.
I was able to do it by inspecting the stack and looking for the view then looking at the local variables for the view to get the request. It feels like a bit of a hack, but it worked.
import inspect, os
#receiver(post_save, sender=MyModel)
def get_user_in_signal(sender, **kwargs):
for entry in reversed(inspect.stack()):
if os.path.dirname(__file__) + '/views.py' == entry[1]:
try:
user = entry[0].f_locals['request'].user
except:
user = None
break
if user:
# do stuff with the user variable
Ignacio is right. Django's model signals are intended to notify other system components about events associated with instances and their respected data, so I guess it's valid that you cannot, say, access request data from a model post_save signal, unless that request data was stored on or associated with the instance.
I guess there are lots of ways to handle it, ranging from worse to better, but I'd say this is a prime example for creating class-based/function-based generic views that will automatically handle this for you.
Have your views that inherit from CreateView, UpdateView or DeleteView additionally inherit from your AuditMixin class if they handle verbs that operate on models that need to be audited. The AuditMixin can then hook into the views that successfully create\update\delete objects and create an entry in the database.
Makes perfect sense, very clean, easily pluggable and gives birth to happy ponies. Flipside? You'll either have to be on the soon-to-be-released Django 1.3 release or you'll have to spend some time fiddlebending the function-based generic views and providing new ones for each auditing operation.
You can do that with the help of middleware. Create get_request.py in your app. Then
from threading import current_thread
from django.utils.deprecation import MiddlewareMixin
_requests = {}
def current_request():
return _requests.get(current_thread().ident, None)
class RequestMiddleware(MiddlewareMixin):
def process_request(self, request):
_requests[current_thread().ident] = request
def process_response(self, request, response):
# when response is ready, request should be flushed
_requests.pop(current_thread().ident, None)
return response
def process_exception(self, request, exception):
# if an exception has happened, request should be flushed too
_requests.pop(current_thread().ident, None)
Then add this middleware to your settings:
MIDDLEWARE = [
....
'<your_app>.get_request.RequestMiddleware',
]
Then add import to your signals:
from django.db.models.signals import post_save
from django.contrib.auth.models import User
from <your_app>.get_request import current_request
# CORE - SIGNALS
# Core Signals will operate based on post
def after_save_handler_attr_audit_obj(sender, **kwargs):
print(Current User, current_request().user)
print User.get_profile()
if hasattr(kwargs['instance'], 'audit_obj'):
if kwargs['created']:
kwargs['instance'].audit_obj.create(operation="INSERT", operation_by=**USER.ID**).save()
else:
kwargs['instance'].audit_obj.create(operation="UPDATE").save()
# Connect the handler with the post save signal - Django 1.2
post_save.connect(after_save_handler_attr_audit_obj, dispatch_uid="core.models.audit.new")
Why not adding a middleware with something like this :
class RequestMiddleware(object):
thread_local = threading.local()
def process_request(self, request):
RequestMiddleware.thread_local.current_user = request.user
and later in your code (specially in a signal in that topic) :
thread_local = RequestMiddleware.thread_local
if hasattr(thread_local, 'current_user'):
user = thread_local.current_user
else:
user = None
For traceability add two attributes to your Model(created_by and updated_by), in "updated_by" save the last user who modified the record. Then in your signal you have the user:
models.py:
class Question(models.Model):
question_text = models.CharField(max_length=200)
pub_date = models.DateTimeField('date published')
created_by = models. (max_length=100)
updated_by = models. (max_length=100)
views.py
p = Question.objects.get(pk=1)
p.question_text = 'some new text'
p.updated_by = request.user
p.save()
signals.py
#receiver(pre_save, sender=Question)
def do_something(sender, instance, **kwargs):
try:
obj = Question.objects.get(pk=instance.pk)
except sender.DoesNotExist:
pass
else:
if not obj.user == instance.user: # Field has changed
# do something
print('change: user, old=%s new=%s' % (obj.user, instance.user))
You could also use django-reversion for this purpose, e.g.
from reversion.signals import post_revision_commit
import reversion
#receiver(post_save)
def post_revision_commit(sender, **kwargs):
if reversion.is_active():
print(reversion.get_user())
Read more on their API https://django-reversion.readthedocs.io/en/stable/api.html#revision-api
You can do a small hack by overriding you model save() method and setting the user on the saved instance as additional parameter. To get the user I used get_current_authenticated_user() from django_currentuser.middleware.ThreadLocalUserMiddleware (see https://pypi.org/project/django-currentuser/).
In your models.py:
from django_currentuser.middleware import get_current_authenticated_user
class YourModel(models.Model):
...
...
def save(self, *args, **kwargs):
# Hack to pass the user to post save signal.
self.current_authenticated_user = get_current_authenticated_user()
super(YourModel, self).save(*args, **kwargs)
In your signals.py:
#receiver(post_save, sender=YourModel)
def your_model_saved(sender, instance, **kwargs):
user = getattr(instance, 'current_authenticated_user', None)
PS: Don't forget to add 'django_currentuser.middleware.ThreadLocalUserMiddleware' to your MIDDLEWARE_CLASSES.
I imagine you would have figured this out, but I had the same problem and I realised that all the instances I create had a reference to the user that creates them (which is what you are looking for)
it's possible i guess.
in models.py
class _M(models.Model):
user = models.ForeignKey(...)
in views.py
def _f(request):
_M.objects.create(user=request.user)
in signals.py
#receiver(post_save, sender=_M)
def _p(sender, instance, created, **kwargs):
user = instance.user
No ?
Request object can be obtained from frame record by inspecting.
import inspect
request = [
frame_record[0].f_locals["request"]
for frame_record in inspect.stack()
if frame_record[3] == "get_response"
][0]
def get_requested_user():
import inspect
for frame_record in inspect.stack():
if frame_record[3] == 'get_response':
request = frame_record[0].f_locals['request']
return request.user
else:
return None
context_processors.py
from django.core.cache import cache
def global_variables(request):
cache.set('user', request.user)
----------------------------------
in you model
from django.db.models.signals import pre_delete
from django.dispatch import receiver
from django.core.cache import cache
from news.models import News
#receiver(pre_delete, sender=News)
def news_delete(sender, instance, **kwargs):
user = cache.get('user')
in settings.py
TEMPLATE_CONTEXT_PROCESSORS = (
'web.context_processors.global_variables',
)