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974

answers:

3

Hello In a model I have a such field: mydate = models.DateField()

now a javascript graph function requires unix timestamp such as "1196550000000", how can I return the unix timestamp of my mydate input.

Thanks

+1  A: 

In your views.py, you can convert the value of mydate to seconds since the Unix epoch as follows:

seconds = time.mktime(mydate.timetuple())

Then pass it in the dictionary you use as an argument to render_to_response() (or whatever you're using to render your view), and in your template, stick {{seconds}} into a hidden field, which you can then pull out of the DOM to pass to your javascript graph function.

Note that a DateField maps to the Python object datetime.date, and as such, its timetuple will have its hours, minutes and seconds fields set to 0. If that's not fine-grained enough for you, you'll need to change mydate to a DateTimeField and it'll be a datetime.datetime. You can still use mydate.timetuple() if you do this.

Also, I'm assuming you're using local time. If you're using UTC time, you want calendar.gmtime() rather than time.mktime() and mydate.utctimetuple() rather than mydate.timetuple(), but utctimetuple() is only a valid method for datetime.datetime objects. See the datetime docs (also time and calendar) for more fiddly details.

EDIT: fiddly details such as the fact that mktime() returns a float, which piquadrat remembered and I didn't. The custom-filter approach is also a good one. Voting that one up.

Meredith L. Patterson
+2  A: 

In python code, you can do this to convert a date or datetime to the Unix Epoch

import time
epoch = int(time.mktime(mydate.timetuple())*1000)

This doesn't work in a Django template though, so you need a custom filter, e.g:

import time

from django import template

register = template.Library()

@register.filter
def epoch(value):
    try:
        return int(time.mktime(value.timetuple())*1000)
    except AttributeError:
        return ''
piquadrat
what i don't get: why not use the strftime() method of the date class and be rid of the time module altogether?
hop
A: 

I know another anwser was accepted a while ago, but this question appears high on Google's search results, so I will add another answer.

If you are working at the template level, you can use the U parameter to the date filter, e.g.:

{{ mydate|date:"U" }}

Note that it will be based upon the TIMEZONE in your settings.py.

John Paulett