For example, I have a function in my views.py to post availability of food. However, I do not want the user to keep creating new instances of available food. I only want the user to be able to update that value. Right now, I have restricted the user to just create a food availability instance and then am not allowing the user to create another one. However, I do not want it as such; I want the user to be able to just update that number.
This is what I have now:
def check_existing_post(request):
data = request.POST.copy()
data["author"] = request.user
if len(Food_Avail.objects.filter(author=request.user)) > 0:
return False
else:
return True
def post_available_food(request):
instance = Food_Avail()
data = request.POST.copy()
data["author"] = request.user
form = FoodAvailForm(data or None, instance=instance)
if request.POST and form.is_valid() and check_existing_post(request):
form.save()
return HttpResponseRedirect(reverse("accounts:home"))
else:
messages.info(
request, "food availability by restaurant has already been posted!"
)
return render(request, "food_avail/post_food_avail.html", {"food": form})
You can fetch the object that belongs to that user, and pass it as instance=… to the form:
from django.shortcuts import get_object_or_404, redirect
from django.contrib.auth.decorators import login_required
@login_required
def post_available_food(request):
instance = get_object_or_404(Food_Avail, author=request.user)
if request.method == 'POST':
form = FoodAvailForm(request.POST, request.FILES, instance=instance)
if form.is_valid():
form.save()
return redirect('accounts:home')
else:
form = FoodAvailForm(instance=instance)
)
return render(request, 'food_avail/post_food_avail.html', {'food': form})Note: Models in Django are written in PascalCase, not snake_case, so you might want to rename the model from
toFood_AvailFoodAvail.
Note: You can limit views to a view to authenticated users with the
@login_requireddecorator [Django-doc].