django定期执行任务(实例讲解)

polls/
  __init__.py 
  models.py 
  management/
    __init__.py 
    commands/
      __init__.py 
      _private.py 
      closepoll.py 
  tests.py 
  views.py 

from django.core.management.base import BaseCommand, CommandError 
from polls.models import Poll 
 
class Command(BaseCommand): 
  help = 'Closes the specified poll for voting'
 
  def add_arguments(self, parser): 
    parser.add_argument('poll_id', nargs='+', type=int) 
 
  def handle(self, *args, **options): 
    for poll_id in options['poll_id']: 
      try: 
        poll = Poll.objects.get(pk=poll_id) 
      except Poll.DoesNotExist: 
        raise CommandError('Poll "%s" does not exist' % poll_id) 
 
      poll.opened = False
      poll.save() 
 
      self.stdout.write(self.style.SUCCESS('Successfully closed poll "%s"' % poll_id))

def add_arguments(self, parser): 
parser.add_argument('poll_id', nargs='+', type=int) 

python manage.py closepoll <poll_id> 

class Command(BaseCommand): 
  def add_arguments(self, parser): 
    # Positional arguments 
    parser.add_argument('poll_id', nargs='+', type=int) 
 
    # Named (optional) arguments 
    parser.add_argument('--delete', 
      action='store_true', 
      dest='delete', 
      default=False, 
      help='Delete poll instead of closing it') 
 
  def handle(self, *args, **options): 
    # ... 
    if options['delete']: 
      poll.delete()

# m h dom mon dow  command 

* */2 * * * python manage.py closepoll <poll_id>

sudo service cron restart