chore(csv_export): add time loggers

Author: jbarreau

django_forest/resources/associations/views/csv.py

@@ -1,5 +1,6 @@
 import logging
 import csv
+import time
 
 from django_forest.resources.associations.utils import AssociationView
 from django_forest.resources.utils.csv import CsvMixin
@@ -13,6 +14,7 @@
 
 class CsvView(SmartFieldMixin, JsonApiSerializerMixin, CsvMixin, AssociationView):
     def get(self, request, pk, association_resource):
+        t0 = time.time()
         try:
             association_field = get_association_field(self.Model, association_resource)
         except Exception as e:
@@ -25,15 +27,25 @@ def get(self, request, pk, association_resource):
             queryset = getattr(self.Model.objects.get(pk=pk), association_resource).all()
 
             params = request.GET.dict()
+
+            t2 = time.time()
             # enhance queryset
             queryset = self.enhance_queryset(queryset, RelatedModel, params, request, apply_pagination=False)
+            for _ in queryset[0:1]:  # force SQL request execution
+                pass
 
+            t3 = time.time()
+            logger.warning(f"-- timing enhance_queryset: {(t3 - t2):.2f} seconds")
             # handle smart fields
             self.handle_smart_fields(queryset, RelatedModel._meta.db_table, parse_qs(params), many=True)
 
+            t4 = time.time()
+            logger.warning(f"-- timing smart fields: {(t4 - t3):.2f} seconds")
             # json api serializer
             data = self.serialize(queryset, RelatedModel, params)
 
+            t5 = time.time()
+            logger.warning(f"-- timing json api serialization: {(t5 - t4):.2f} seconds")
             response = self.csv_response(params['filename'])
 
             field_names_requested = [x for x in params[f'fields[{RelatedModel._meta.db_table}]'].split(',')]
@@ -42,4 +54,7 @@ def get(self, request, pk, association_resource):
             writer = csv.DictWriter(response, fieldnames=field_names_requested)
             writer.writerow(dict(zip(field_names_requested, csv_header)))
             self.fill_csv(data, writer, params)
+            t6 = time.time()
+            logger.warning(f"-- timing csv serialization into response body: {(t6 - t5):.2f} seconds")
+            logger.warning(f"--- total timing: {(t6 - t0):.2f} seconds")
             return response