Reputation: 20163
I have the following simple view. Why is it resulting in this error?
The view auth_lifecycle.views.user_profile didn't return an HttpResponse object. It returned None instead.
"""Renders web pages for the user-authentication-lifecycle project."""
from django.shortcuts import render
from django.template import RequestContext
from django.contrib.auth import authenticate, login
def user_profile(request):
"""Displays information unique to the logged-in user."""
user = authenticate(username='superuserusername', password='sueruserpassword')
login(request, user)
render(request, 'auth_lifecycle/user_profile.html',
context_instance=RequestContext(request))
Upvotes: 63
Views: 262771
Reputation: 141
I know this is very late to post something here but this may help out someone to figure out the silly mistake.
That there are chances that you are missing return
before render()
. please make sure that.
Upvotes: 9
Reputation: 88689
In Django, every view is required to return an HttpResponse (or one of its subclasses). However, it is common to use the render(...)
function to render templates in Django. Using render(...)
ensures that the view will not encounter errors, as render(...)
returns an HttpResponse internally.
Coming to this specific case, you're missing a return
statement, and thus the view did return None
, which caused the exception.
So, adding a return
statement will solve the issue, as below
def user_profile(request):
# your code
return render(...)
^^^^^^
Many people face this issue; their code/logic may differ, but the reason will be the same. Here are a few scenarios that may help you to troubleshoot the situation,
return
statement?def user_profile(request):
HttpResponse("Success") # missing a `return` here
HttpResponse
or its a subclass? Some people may return the model object or form object directly from the viewdef user_profile(request):
my_model_object = MyModel.objects.get(pk=request.GET.get('id'))
# at last, return a model instance
return my_model_object
Does all your if...else
clauses properly return a HttpResponse
? (In the following example, It is not clear what should return,
a. in case the form.is_valid()
is False
b. in case the form.is_valid()
is True
(after form.save()
)
def user_profile(request):
if request.method == "POST":
form = UserProfileForm(request.POST, instance=request.user)
if form.is_valid():
form.save()
else:
return render(
request,
"user_profile.html",
{"form": UserProfileForm(instance=request.user)},
)
Upvotes: 3
Reputation: 20163
Because the view must return render
, not just call it. (Note that render
is a simple wrapper around an HttpResponse
). Change the last line to
return render(request, 'auth_lifecycle/user_profile.html',
context_instance=RequestContext(request))
(Also note the render(...)
function returns a HttpResponse
object behind the scenes.)
Upvotes: 121
Reputation: 21
I have the same issue but resolved it by returning the render after saving the data.
error_message = None
if not first_name:
error_message = "first name is required!!!!"
elif len(first_name) < 4:
error_message = "first name must be more than 4 characters!!!"
elif not error_message:
signup_obj = Signuup(firstname=first_name, lastname=last_name, email=email, password=password)
print("here is the complete object!!!!")
signup_obj.register()
else:
return render(request, 'signup.html', {'error': error_message})
Issue: After saving data if I do not have any error_message to show but I am not returning anything after saving.
Solution Error solved after adding
signup_obj.register()
return render(request, 'signup.html')
In the code....
Upvotes: 0
Reputation: 69
Python is very sensitive to indentation, with the code below I got the same error:
except IntegrityError as e:
if 'unique constraint' in e.args:
return render(request, "calender.html")
The correct indentation is:
except IntegrityError as e:
if 'unique constraint' in e.args:
return render(request, "calender.html")
Upvotes: 0
Reputation: 713
if qs.count()==1:
print('cart id exists')
if ....
else:
return render(request,"carts/home.html",{})
Such type of code will also return you the same error this is because of the intents as the return statement should be for else not for if statement.
above code can be changed to
if qs.count()==1:
print('cart id exists')
if ....
else:
return render(request,"carts/home.html",{})
This may solve such issues
Upvotes: 15
Reputation: 753
I had the same error using an UpdateView
I had this:
if form.is_valid() and form2.is_valid():
form.save()
form2.save()
return HttpResponseRedirect(self.get_success_url())
and I solved just doing:
if form.is_valid() and form2.is_valid():
form.save()
form2.save()
return HttpResponseRedirect(reverse_lazy('adopcion:solicitud_listar'))
Upvotes: 5