fix(django): add error when trying to insert binary data

django_bulk_load/django.py

@@ -1,4 +1,6 @@
+import base64
 import csv
+import os
 from io import StringIO
 from typing import Any, Iterable, List, NamedTuple, Optional, Tuple, Type
 
@@ -69,7 +71,11 @@ def models_to_tsv_buffer(
         row = []
         for include_field in include_fields:
             field_val = django_field_to_value(obj, include_field, connection)
-            if field_val is None:
+            if isinstance(field_val, connection.Database.Binary):
+                # We can migrate to psychopg 3 which has more advanced copy commands for binary once we upgrade
+                # Django to 4.1+
+                raise ValueError("Binary data is not supported in bulk operations")
+            elif field_val is None:
                 row.append(NULL_CHARACTER)
             elif isinstance(field_val, Json):
                 row.append(field_val.dumps(field_val.adapted))

docker-compose.yml

@@ -6,8 +6,14 @@ services:
       - .:/python
     working_dir: /python
     depends_on:
-      - db
+      db:
+        condition: service_healthy
   db:
     image: postgres:10
+    healthcheck:
+      test: [ "CMD-SHELL", "pg_isready -U postgres" ]
+      interval: 5s
+      timeout: 5s
+      retries: 5
     environment:
       - POSTGRES_PASSWORD=postgres

tests/test_bulk_insert_models.py

@@ -168,3 +168,17 @@ def test_errors_when_mix_of_pk_and_not(self):
                 unsaved_model_with_pk,
                 unsaved_model_without_pk
             ])
+
+    def test_errors_when_uploading_binary(self):
+        unsaved_model1 = TestComplexModel(
+            binary_field=b"hello2",
+        )
+        unsaved_model2 = TestComplexModel(
+            binary_field=b"hello2",
+        )
+
+        with self.assertRaises(ValueError):
+            bulk_insert_models([
+                unsaved_model1,
+                unsaved_model2
+            ])

tests/test_project/models.py

@@ -14,6 +14,7 @@ class TestComplexModel(models.Model):
     test_foreign = models.ForeignKey(
         TestForeignKeyModel, on_delete=models.PROTECT, null=True
     )
+    binary_field = models.BinaryField(null=True)