🐛(backend) create_for_owner: add accesses before saving doc content

We add the User Accesses before saving content so the user is sure to
have access to the the first version when creating a doc through
create_for_owner (fixes #2123)

CHANGELOG.md

@@ -10,6 +10,10 @@ and this project adheres to
 
 - 💄(frontend) improve comments highlights #1961
 
+### Fixed
+
+- 🐛(backend) create_for_owner: add accesses before saving doc content #2124
+
 ## [v4.8.3] - 2026-03-23
 
 ### Changed

src/backend/core/api/serializers.py

@@ -507,7 +507,6 @@ class ServerCreateDocumentSerializer(serializers.Serializer):
 
         document = models.Document.add_root(
             title=validated_data["title"],
-            content=document_content,
             creator=user,
         )
 
@@ -526,6 +525,9 @@ class ServerCreateDocumentSerializer(serializers.Serializer):
                 role=models.RoleChoices.OWNER,
             )
 
+        document.content = document_content
+        document.save()
+
         self._send_email_notification(document, validated_data, email, language)
         return document
 

src/backend/core/tests/documents/test_api_documents_create_for_owner.py

@@ -594,6 +594,43 @@ def test_api_documents_create_for_owner_with_converter_exception(
     assert response.json() == {"content": ["Could not convert content"]}
 
 
+@override_settings(SERVER_TO_SERVER_API_TOKENS=["DummyToken"])
+def test_api_documents_create_for_owner_access_before_content():
+    """
+    Accesses must exist before content is saved to object storage so the owner
+    has access to the very first version of the document.
+    """
+    user = factories.UserFactory()
+    accesses_at_save_time = []
+
+    original_save_content = Document.save_content
+
+    def capturing_save_content(self, content):
+        accesses_at_save_time.extend(
+            list(self.accesses.values_list("user__sub", "role"))
+        )
+        return original_save_content(self, content)
+
+    data = {
+        "title": "My Document",
+        "content": "Document content",
+        "sub": str(user.sub),
+        "email": user.email,
+    }
+
+    with patch.object(Document, "save_content", capturing_save_content):
+        response = APIClient().post(
+            "/api/v1.0/documents/create-for-owner/",
+            data,
+            format="json",
+            HTTP_AUTHORIZATION="Bearer DummyToken",
+        )
+
+    assert response.status_code == 201
+    # The owner access must already exist when save_content is called
+    assert (str(user.sub), "owner") in accesses_at_save_time
+
+
 @override_settings(SERVER_TO_SERVER_API_TOKENS=["DummyToken"])
 def test_api_documents_create_for_owner_with_empty_content():
     """The content should not be empty or a 400 error should be raised."""