Question

I’m trying to costomise the display in the admin interface. I need one of the fields to display the name and date submitted for photo sharing site I’m creating, but I keep getting the following error:

global name 'datetimeConvertToHumanReadable' is not defined

Here’s the full traceback: http://dpaste.com/822073/

My code

Model:

class Design(models.Model):
    designer_id = models.ForeignKey(User)
    date_submitted = models.DateTimeField()
    title = models.CharField(max_length=70)
    description = models.TextField()
    photo = models.FileField(upload_to='design_photos')

    def image_thumb(self):
        return '<img src="/media/%s" width="100" height="100" />' % (self.photo)
    image_thumb.allow_tags = True

    def datetimeConvertToHumanReadable(dt):

        # convert passed datetime to timestamp
        dt_stamp = dt.strftime("%s")

        # convert current datetime to timestamp
        now = datetime.datetime.now()
        now_stamp = now.strftime("%s")

        # find difference between the two
        delta = int(now_stamp) - int(dt_stamp)

        # convert to (seconds ago, minutes ago, hours ago, etc...)
        if (delta < 60):
            return str(delta) + " seconds ago"
        elif (delta < 3600):
            return str(delta/60) + " minutes ago"
        elif (delta < 86400):
            return str(delta/3600) + " hours ago"
        elif (delta < 31536000):
            return str(delta/86400) + " days ago"
        else:
            return str(delta/31536000) + " years ago"

    def name_and_submitted(self):
        date_submitted = datetimeConvertToHumanReadable(date_submitted) 
        return '<div>%s<br />submitted %s ago</div>' % (self.designer_id, self.date_submitted)

    def __unicode__(self):
        return self.title

Admin.py:

class DesignAdmin(admin.ModelAdmin):

    list_display = ('image_thumb', 'title', 'description', 'name_and_submitted')

The image_thumb method works fine to display a thumbnail in the field, but the name_and_submitted method throws up the error. Any ideas?

Answer 1

Just pass the self argument. That should solve the problem

def datetimeConvertToHumanReadable(self):
    dt = self.date_submitted
    # rest of your code goes here

The problem is that, when you are not passing the self argument, the function is not attached to the class and not callable through a model object. list_admin_display actually access the model instance and calls the function. In your case, it would be something like design_object.datetimeConvertToHumanReadable where design_object is each model instance displayed in the admin page. The argument dt is not passed as an argument, so you need to extract it within your function.

Hope this helps