add non existing field name to django query-CodePudding

I'm trying to add extra field name base on its sub domains, but i cant do that, here is my views.py

def daily_vistors_detail_html(request):

    address = request.build_absolute_uri('/')
    host_name = address.partition('://')[2]
    sub_addr = host_name.partition('.')[0]
    hotel_name = 'hotel 1'
    if sub_addr == 'hotel 2':
        hotel_name = 'hotel 2'

    lists = MyModel.objects.annotate(hotel_name=hotel_name).order_by('-pk')
context = {
    'lists':lists
}

but it returns

QuerySet.annotate() received non-expression(s): hotel 1. is there away to achieve that please?

thank you

CodePudding user response：

I think what you search is the annotation of a Value.

# Import Value:
from django.db.models import Value

def daily_vistors_detail_html(request):

    address = request.build_absolute_uri('/')
    host_name = address.partition('://')[2]
    sub_addr = host_name.partition('.')[0]
    hotel_name = 'hotel 1'
    if sub_addr == 'hotel 2':
        hotel_name = 'hotel 2'

    # Annotate content of hotel_name as Value:
    lists = MyModel.objects.annotate(hotel_name=Value(hotel_name)).order_by('-pk')
context = {
    'lists':lists
}

You can find the docs here: Django Docs