python 37 lines · 7 steps

Filtering and paginating a Django product list

A view builds a lazy queryset step by step from URL parameters, then paginates it for the template.

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Django Intermediate queryset pagination filtering lazy-evaluation request-parsing
1from django.core.paginator import Paginator
2from django.shortcuts import render
3 
4from .models import Product
5 
6 
7def product_list(request):
8 products = Product.objects.select_related("category").order_by("-created_at")
9 
10 category = request.GET.get("category")
11 if category:
12 products = products.filter(category__slug=category)
13 
14 search = request.GET.get("q", "").strip()
15 if search:
16 products = products.filter(name__icontains=search)
17 
18 in_stock = request.GET.get("in_stock")
19 if in_stock == "1":
20 products = products.filter(stock__gt=0)
21 
22 paginator = Paginator(products, 24)
23 page = paginator.get_page(request.GET.get("page"))
24 
25 querystring = request.GET.copy()
26 querystring.pop("page", None)
27 
28 return render(
29 request,
30 "catalog/product_list.html",
31 {
32 "page": page,
33 "querystring": querystring.urlencode(),
34 "category": category,
35 "search": search,
36 },
37 )
01 / 01
STEP 01

Walkthrough

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Three takeaways
  1. 1Django querysets are lazy, so chaining filters conditionally builds no database work until the page is actually sliced.
  2. 2Reading filters straight from request.GET lets one view handle category, search, and stock combinations without extra routes.
  3. 3Stripping the page key from a copied querystring keeps pagination links carrying every other active filter.

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