Django: Setting one page as the main page

I'm a newbie at Django and I want to do something that I'm not sure how to do.

I have a model SimplePage, which simply stands for a webpage that is visible on the website and whose contents can be edited in the admin. (I think this is similar to FlatPage.)

So I have a bunch of SimplePages for my site, and I want one of them to be the main page. (a.k.a. the index page.) I know how to make it available on the url /. But I also want i开发者_运维技巧t to receive slightly different processing. (It contains different page elements than the other pages.)

What would be a good way to mark a page as the main page? I considered adding a boolean field is_main_page to the SimplePage model, but how could I assure that only one page could be marked as the main page?

---

Create MAIN_PAGE setting inside settings.py with primary key. Then create view main_page nad retrieve the main_page object from the database using the setting.

EDIT:

You can also do it like this: add a model, which will reference a SimplePage and point to the main page. In main page view, you will retrieve the wanted SimplePage and it can be easily changed by anyone in django admin.

---

Easiest way to do this would be to create the boolean value, as you suggested and use the pre_save signal to remove the boolean value from everything else in the database.

from django.db.models import signals
def simple_page_pre_save(sender, instance, **kwargs):
    if instance.is_main_page == True:
        SimplePage.objects.update(is_main_page=False)

signals.pre_save.connect(simple_page_pre_save, sender=SimplePage)

This way whenever you save a SimplePage, it will see if is_main_page is true, and if it is set is_main_page for every other page to False. There is still some work to be done to ensure that there is always one is_main_page, but that is more up to you.