feat: DIA-2206: prefetch completed_by info (#7417)

Co-authored-by: matt-bernstein <matt-bernstein@users.noreply.github.com>
Co-authored-by: hakan458 <hakan@heartex.com>

Author: 3 people

label_studio/data_export/mixins.py

@@ -25,7 +25,7 @@
 from django.db.models.query_utils import Q
 from django.utils import dateformat, timezone
 from label_studio_sdk.converter import Converter
-from tasks.models import Annotation, Task
+from tasks.models import Annotation, AnnotationDraft, Task
 
 ONLY = 'only'
 EXCLUDE = 'exclude'
@@ -96,27 +96,29 @@ def _get_filtered_annotations_queryset(self, annotation_filter_options=None):
         })
         """
         queryset = Annotation.objects.all()
-        if not isinstance(annotation_filter_options, dict):
-            return queryset
-
-        q_list = []
-        if annotation_filter_options.get('usual'):
-            q_list.append(Q(was_cancelled=False, ground_truth=False))
-        if annotation_filter_options.get('ground_truth'):
-            q_list.append(Q(ground_truth=True))
-        if annotation_filter_options.get('skipped'):
-            q_list.append(Q(was_cancelled=True))
-        if not q_list:
-            return queryset
-
-        q = reduce(lambda x, y: x | y, q_list)
-        annotations_qs = queryset.filter(q)
-
+        if isinstance(annotation_filter_options, dict):
+            q_list = []
+            if annotation_filter_options.get('usual'):
+                q_list.append(Q(was_cancelled=False, ground_truth=False))
+            if annotation_filter_options.get('ground_truth'):
+                q_list.append(Q(ground_truth=True))
+            if annotation_filter_options.get('skipped'):
+                q_list.append(Q(was_cancelled=True))
+            if q_list:
+                q = reduce(lambda x, y: x | y, q_list)
+                queryset = queryset.filter(q)
+
+        # pre-select completed_by user info
+        queryset = queryset.select_related('completed_by')
         # prefetch reviews in LSE
-        if hasattr(annotations_qs.model, 'reviews'):
-            annotations_qs = annotations_qs.prefetch_related('reviews')
+        if hasattr(queryset.model, 'reviews'):
+            from reviews.models import AnnotationReview
+
+            queryset = queryset.prefetch_related(
+                Prefetch('reviews', queryset=AnnotationReview.objects.select_related('created_by'))
+            )
 
-        return annotations_qs
+        return queryset
 
     @staticmethod
     def _get_export_serializer_option(serialization_options):
@@ -153,13 +155,12 @@ def get_task_queryset(self, ids, annotation_filter_options):
 
         return (
             Task.objects.filter(id__in=ids)
+            .select_related('file_upload')  # select_related more efficient for regular foreign-key relationship
             .prefetch_related(
-                Prefetch(
-                    'annotations',
-                    queryset=annotations_qs,
-                )
+                Prefetch('annotations', queryset=annotations_qs),
+                Prefetch('drafts', queryset=AnnotationDraft.objects.select_related('user')),
+                'comment_authors',
             )
-            .prefetch_related('predictions', 'drafts', 'comment_authors', 'file_upload')
         )
 
     def get_export_data(self, task_filter_options=None, annotation_filter_options=None, serialization_options=None):