Optimise get_paf_for_review().

Author: frjo

hypha/apply/dashboard/services.py

@@ -1,28 +1,28 @@
-from django.db.models import Count
+from django.db.models import Count, Exists, OuterRef
 
 from hypha.apply.projects.models import PAFApprovals
 
 
 def get_paf_for_review(user, is_paf_approval_sequential):
-    """Return a list of paf approvals ready for user's review"""
+    """Return a queryset of paf approvals ready for user's review"""
+    user_groups = list(user.groups.all())
 
     paf_approvals = PAFApprovals.objects.annotate(
         roles_count=Count("paf_reviewer_role__user_roles")
     ).filter(
-        roles_count=user.groups.count(),
+        roles_count=len(user_groups),
         approved=False,
     )
 
-    for role in user.groups.all():
+    for role in user_groups:
         paf_approvals = paf_approvals.filter(paf_reviewer_role__user_roles__id=role.id)
 
     if is_paf_approval_sequential:
-        all_matched_paf_approvals = list(paf_approvals)
-        for matched_paf_approval in all_matched_paf_approvals:
-            if matched_paf_approval.project.paf_approvals.filter(
-                paf_reviewer_role__sort_order__lt=matched_paf_approval.paf_reviewer_role.sort_order,
-                approved=False,
-            ).exists():
-                paf_approvals = paf_approvals.exclude(id=matched_paf_approval.id)
+        blocking_step = PAFApprovals.objects.filter(
+            project=OuterRef("project"),
+            approved=False,
+            paf_reviewer_role__sort_order__lt=OuterRef("paf_reviewer_role__sort_order"),
+        )
+        paf_approvals = paf_approvals.exclude(Exists(blocking_step))
 
     return paf_approvals

hypha/apply/dashboard/views.py

@@ -82,7 +82,7 @@ def paf_for_review(self):
             get_paf_for_review(
                 user=self.request.user,
                 is_paf_approval_sequential=project_settings.paf_approval_sequential,
-            )
+            ).select_related("project__submission__page", "paf_reviewer_role", "user")
         )
         paf_table = PAFForReviewDashboardTable(
             paf_approvals, prefix="paf-review-", order_by="-date_requested"