I am building a console application that will run at night by the windows task scheduler.
Also there should be an option for when the user starts in manually at the middle of the day that the user should parse a datetime with it.
My question: is there some way to tell the difference inside the console app if the application was started manually or by the task scheduler?
Related
My Django app generates a complex report that can take upto 5 minutes to create. Therefore it runs once a night using a scheduled management command.
That's been ok, except I now want the user to be able to select the date range for the report, which means the report needs to be created while the user waits.
What are my options for running the tast in the background? So far I've found these:
Celery - might work but is complex
django-background-tasks looks like the right tool for the job but hasn't been updated for years, last supported Django is 2.2
The report/background task could be generated by AWS Lambda, basically in a microservice. Django calls the Microservice which can execute the background task then call the Django app back once finished. This is what I did last time but not sure it would work now as I'd need to send the microservice 10mb of data to process.
Use subprocess.popen which someone here said worked for them but other reports say it doesn't work from Django.
EDIT: Looks like Django 3.1 onwards supports ASync views and may be the simple solution for this.
My intention is to run a 3 second web job every 5 min. What happens if I skip the host.RunAndBlock?
If you just want a simple time scheduled job, there is no need to use the WebJobs SDK at all, so there is no host at all. Just use a plain console app (can be as simple as a one line Main), and deploy it as a scheduled CRON WebJobs. See https://learn.microsoft.com/en-us/azure/app-service/web-sites-create-web-jobs.
I know there are many questions asking about this, especially this one: Django - Set Up A Scheduled Job?.
But what I want to understand is, how does a scheduled task inside Django actually works?
My simplistic way to think about it is that there's an infinite loop somewhere, something like this (runs every 60 seconds),
import time
interval=60 #60 seconds
while True:
some_method()
time.sleep(interval)
Question: where do you put this infinite loop? Is there some part of the Django app that just runs in the background alongside the rest of the app?
Thanks!
Django doesn't do scheduled tasks. If you want scheduled tasks, you need a daemon that runs all the time and can launch your task at the appropriate time.
Django only runs when a http request is made. If no one makes a http request for a month, django doesn't run for a month. If there are 45 http requests this second, django will run 45 times this second (in the absence of caching).
You can write scripts in the django framework (called management commands) that get called from some outside service (like cron). That's as close as you'll get to what you want. If that's the case, then the question/answer you reference is the place to get the how tos.
Probably on a unixy system, cron is the simplest outside service to work with. On recent linux systems, cron has a directory /etc/cron.d into which you can drop your app's cron config file, and it will not interfere with any other cron jobs on the system. No editing of existing files necessary.
i want to schedule a job in SAS-DIS. i tried the process using sas management console,bt an error is popping up saying scheluing server not found.
can anyone help me how to setup a scheduling server? or is it a software to be installed?
Thanks
I think a scheduling server is an extra package that has to be purchased. Our BI setup is lacking that option and no matter what we can't seem to get it approved. Check with your SAS server admin to see if the job scheduling has been enabled. If so he/she should be able to tell you the process for getting it scheduled.
Alternatively, without a scheduling server you still deploy your jobs and can either use
1. Cron and Crontab (in Unix or Linux)
2. Windows OS scheduler
to schedule jobs manually as this is the best option available if there is none. I know this can be very tedious and cumbersome , but can give it a try if you have less number of jobs to schedule.
I have a program that classifies text and would like to make it interactive with a user on the front-end of my django site. The problem is it takes 20 seconds for the program to load the training set and get going, and that's not feasible every time someone enters input.
Instead, I'd like Django to load the program once when the server starts, and have all user input interact with it via a view.
I looked at launching subprocesses, but if I'm not mistaken, a subprocess would only be launched when a view is called and that is undesirable for this.
Any ideas?
Thanks.
It's possible that Celery would be appropriate here. There is Django integration available with django-celery.
As Jim noticed celery is one of the best options you have for asynchronus task management, but if you want to avoid celery & its dependecies overhead you could just add a status field on the model the process takes place (e.g. text_processed boolean field with default=False) and create an application management command which would handle the process of the created db entries.
Add the command on a cron and you are done.