Pagination

project/main/views/filter_list.py

@@ -1,7 +1,7 @@
-from dataclasses import dataclass
-from typing import Any, Tuple
+from typing import Any
 
-from django.db.models import Model, Q, QuerySet
+from django.core.paginator import Page, Paginator
+from django.db.models import Q, QuerySet
 
 from project.main.models import Area, County
 from project.main.views.demo_view_base import DemoViewBase
@@ -13,34 +13,16 @@ def get_all_counties() -> QuerySet[County]:
     return County.objects.all()
 
 
-@dataclass
-class Pagination:
-    page: int
-    page_size: int
-    page_count: int
-    prev_page: int
-    next_page: int
-
-
 class FilterListViewBase(DemoViewBase):
-    def paginate(self, qs: QuerySet[Area]) -> Tuple[QuerySet[Area], Pagination]:
+    def paginate(self, qs: QuerySet[Area]) -> Page:
         page = int(self.request.GET.get("page", 1))
         page_size = int(self.request.GET.get("page_size", PAGE_SIZE))
 
-        start_offs = (page - 1) * page_size
-        end_offs = start_offs + page_size
-
-        page_count = int(qs.count() / page_size)
-
-        pagination = Pagination(
-            page=page,
-            page_size=page_size,
-            page_count=page_count,
-            prev_page=page - 1 if page > 1 else None,
-            next_page=page + 1 if page < page_count else None,
+        paginator = Paginator(
+            object_list=qs,
+            per_page=page_size,
         )
-
-        return qs[start_offs:end_offs], pagination
+        return paginator.get_page(page)
 
 
 class FilterListView(FilterListViewBase):
@@ -51,14 +33,13 @@ class FilterListView(FilterListViewBase):
     def get_context_data(self, **kwargs) -> dict[str, Any]:
         context_data = super().get_context_data(**kwargs)
 
-        qs, pagination = self.paginate(
+        page = self.paginate(
             qs=Area.objects.select_related("county", "post_office").all(),
         )
         context_data.update(
             {
-                "areas": qs,
+                "page": page,
                 "counties": get_all_counties(),
-                "pagination": pagination,
             }
         )
         return context_data
@@ -82,15 +63,14 @@ class FilterListFilterView(FilterListViewBase):
         if county:
             q &= Q(county_id=county)
 
-        qs, pagination = self.paginate(
+        page = self.paginate(
             qs=Area.objects.select_related("county", "post_office").filter(q),
         )
 
         context_data.update(
             {
-                "areas": qs,
+                "page": page,
                 "counties": get_all_counties(),
-                "pagination": pagination,
             }
         )
         return context_data