chsh

#
# A:
# pubsub = PgPubSub.new('channelname')
# pubsub.subscribe do |data|
#  puts "data: #{data} is coming!"
# end
#
# B:
# pubsub = PgPubSub.new('channelname')
# pubsub.publish("hello world")

balazs-endresz

# https://stackoverflow.com/questions/4916851/django-get-a-queryset-from-array-of-ids-in-specific-order/37648265#37648265

from django.db.models import Case, When

pk_list = [10, 2, 1]
preserved = Case(*[When(pk=pk, then=pos) for pos, pk in enumerate(pk_list)])
queryset = MyModel.objects.filter(pk__in=pk_list).order_by(preserved)


# pre django 1.8: