Django ListView - Form to filter and sort - django

Question

My Goal
A site that list all my Updates (model) in a table
Dont display all models at once (pagination - maybe 10 per page)
Filter and sort the list
My thoughts
I can use ListView to get a set of all my Updates
Use paginate_by = 10
Use a form to set order_by or filter in my QuerySet
My Problem
I am not sure how to add an form to modify my QuerySet with filter and sortings. My Idea was to modify the Query in get_queryset with additional filter and order_by.
My View
class MyView(ListView):
model = Update
template_name = "updates/update.html"
paginate_by = 10
def get_queryset(self):
return Update.objects.filter(
~Q(state=Update.STATE_REJECTED),
~Q(state=Update.STATE_CANCELED),
~Q(state=Update.STATE_FINISHED),
).order_by(
'planned_release_date'
)
My Idea
Something like this. I know it's not working like this ... just to illustrate
class MyView(ListView):
model = Update
template_name = "updates/update.html"
paginate_by = 10
def post(self, request, *args, **kwargs):
new_context = Update.objects.filter(
request.POST.get("filter"),
).order_by(
request.POST.get("sorting"),
)
def get_queryset(self):
return Update.objects.filter(
~Q(state=Update.STATE_REJECTED),
~Q(state=Update.STATE_CANCELED),
~Q(state=Update.STATE_FINISHED),
).order_by(
'planned_release_date'
)

Answer 1

You don't need post. Pass the filter value and order_by in the url for example:
.../update/list/?filter=filter-val&orderby=order-val
and get the filter and orderby in the get_queryset like:
class MyView(ListView):
model = Update
template_name = "updates/update.html"
paginate_by = 10
def get_queryset(self):
filter_val = self.request.GET.get('filter', 'give-default-value')
order = self.request.GET.get('orderby', 'give-default-value')
new_context = Update.objects.filter(
state=filter_val,
).order_by(order)
return new_context
def get_context_data(self, **kwargs):
context = super(MyView, self).get_context_data(**kwargs)
context['filter'] = self.request.GET.get('filter', 'give-default-value')
context['orderby'] = self.request.GET.get('orderby', 'give-default-value')
return context
Make sure you give proper default value to filter and orderby
Example form (you can modify this to your need):
<form method="get" action="{% url 'update-list' %}">
<p>Filter: <input type="text" value={{filter}} name="filter"/></p>
<p>order_by: <input type="text" value={{orderby}} name="orderby"/></p>
<p><input type="submit" name="submit" value="submit"/></p>
</form>

Answer 2

I am wondering why nobody mentioned here this cool library: django-filter https://github.com/carltongibson/django-filter
you can define your logic for filtering very clean and get fast working forms etc.
demo here: https://stackoverflow.com/a/46492378/953553

Answer 3

I posted this elsewhere but I think this adds to the selected answer.
I think you would be better off doing this via get_context_data. Manually create your HTML form and use GET to retrieve this data. An example from something I wrote is below. When you submit the form, you can use the get data to pass back via the context data. This example isn't tailored to your request, but it should help other users.
def get_context_data(self, **kwargs):
context = super(Search, self).get_context_data(**kwargs)
filter_set = Gauges.objects.all()
if self.request.GET.get('gauge_id'):
gauge_id = self.request.GET.get('gauge_id')
filter_set = filter_set.filter(gauge_id=gauge_id)
if self.request.GET.get('type'):
type = self.request.GET.get('type')
filter_set = filter_set.filter(type=type)
if self.request.GET.get('location'):
location = self.request.GET.get('location')
filter_set = filter_set.filter(location=location)
if self.request.GET.get('calibrator'):
calibrator = self.request.GET.get('calibrator')
filter_set = filter_set.filter(calibrator=calibrator)
if self.request.GET.get('next_cal_date'):
next_cal_date = self.request.GET.get('next_cal_date')
filter_set = filter_set.filter(next_cal_date__lte=next_cal_date)
context['gauges'] = filter_set
context['title'] = "Gauges "
context['types'] = Gauge_Types.objects.all()
context['locations'] = Locations.objects.all()
context['calibrators'] = Calibrator.objects.all()
# And so on for more models
return context

Answer 4

This is how we do it, that way you get validation/type conversion as well:
class UnitList(PermissionRequiredMixin, ListView):
""" Class based view to show a list of all buildings for a specific user """
model = Unit
ordering = ['building', 'unit']
paginate_by = 100
# Access
permission_required = ['core.manager_perm']
raise_exception = True # If true, give access denied message rather than redirecting to login
def get_queryset(self):
try:
units = self.model.objects.filter(building__company=self.request.user.profile.company)
except Profile.DoesNotExist:
units = self.model.objects.none()
form = UnitSearchForm(self.request.GET)
if form.is_valid():
filters = {}
address = form.cleaned_data['address']
neighborhood = form.cleaned_data['neighborhood']
beds = form.cleaned_data['beds']
amenity = form.cleaned_data['amenity']
if address:
filters['building__street_index__istartswith'] = compute_street_address_index(address)
if neighborhood:
filters['building__neighborhood__icontains'] = neighborhood
if beds:
filters['beds'] = beds
if amenity:
filters['unit_amenities__name__iexact'] = amenity
units = units.filter(**filters)
return units.select_related('building').order_by(*self.ordering)
def get_context_data(self, **kwargs):
context = super().get_context_data(**kwargs)
context['form'] = UnitSearchForm(self.request.GET)
return context