Django: Please help with this queryset

Question

I have a Django model, shown below, that I use to keep track of which ip addresses visit my site and when.

class Visit(models.Model):
    created         = models.DateTimeField(default=datetime.utcnow)
    ip              = models.IPAddressField(editable=False)

I'd like to write a method on this model that returns the number of days in took for the last 100 visits from a particular IP. Multiple visits in a single day (hour etc) from an IP all count as separate visits. So, if someone visted the site 100 times in the past 2 days, it would return 2, 100 times in the past 8 days, it would return 8, and so on.

Answer 1

An easy approach is to get the last 100 Visit objects for an ip address and count the number of unique created objets in them.

def num_of_dates(ip_addr)    
    dates = [v.created for v in Visit.objects.filter(ip=ip_addr).order_by('-created')[0:100]]
    unique_dates = set(dates)
    return len(unique_dates)

Answer 2

You probably want to change the default= for created_on to be auto_now_add since the datetime.utcnow doesn't update if you're using servers other than the dev server:

class Visit(models.Model):
    created         = models.DateTimeField(auto_now_add=True,editable=False)
    ip              = models.IPAddressField(editable=False)

from datetime import datetime
def days_for_100(ip_addr):
  now = datetime.now()
  dates = Visit.objects.filter(ip=ip_addr)
  if dates.count()<100:
    latest = dates.latest('-created')
  else:
    latest = dates.dates('created','day',order='DESC')[99]
  return (now-latest).days # timedelta.days

This returns how many days earlier the 100th visit ago happened (or how long ago the first visit occurred if there are less than 100 visits)