Django add data from queryset to context

Question

I want to add to template the media values so in the view I get the value in the get_queryset and then add them to template with get_context, but something is wrong :

class LaLista(ListView):

   def get_queryset(self, **kwargs): 
        qs = super(LaLista, self).get_queryset()
        media = qs.aggregate(Avg('A_U'), Max('A_U'), Min('A_U'))
        return qs, media

   def get_context_data(self, **kwargs):
        context = super(LaLista, self).get_context_data(**kwargs)
        context['media'] = media
        return context

in the template I have given:

{{ media }}

and this will return:

NameError: global name 'media' is not defined

Shang Wang · Accepted Answer · 2016-04-12 13:26:38Z

1

You are using a variable media in function get_context_data, but you don't have the variable defined in the function. Python variables are bound within function scope so you cannot use it without defining it first.

You shouldn't query for media in function get_queryset, because get_queryset is meant to get the queryset that ListView will iterate in the template, so it should return only ONE result. If you want extra context, do it in function get_context_data:

def get_context_data(self, **kwargs):
    context = super(LaLista, self).get_context_data(**kwargs)
    # if you didn't define anything special, object_list is the default queryset name
    qs = kwargs['object_list']
    media = qs.aggregate(Avg('A_U'), Max('A_U'), Min('A_U'))

answered Apr 12, 2016 at 13:26

Shang Wang

25.7k21 gold badges77 silver badges95 bronze badges

Sign up to request clarification or add additional context in comments.

1 Comment

user2239318 Over a year ago

Just changed kwargs to self.object_list and work fine.Thank you!

Collectives™ on Stack Overflow

Django add data from queryset to context

1 Answer 1

1 Comment

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

1 Comment

Your Answer

Sign up or log in

Post as a guest

Related