fix(Django): Avoid evaluating complex Django object in span.data/span.attributes (#4804)

### Description
When rendering templates of the Django Admin in Django 5.0+ the template
context includes also a `QuerySet` with lots of log items.
In our `serialize()` function this was not properly serialized leading
to evaluating the `QuerySet` (read: running the SQL query).

This change updates the `serialize()` to also correctly serialize
`QuerySet`s in `span.data`

#### Issues
* resolves: #4604
* resolves: PY-1781

Author: antonpirker

sentry_sdk/serializer.py

@@ -187,6 +187,16 @@ def _is_databag():
 
         return False
 
+    def _is_span_attribute():
+        # type: () -> Optional[bool]
+        try:
+            if path[0] == "spans" and path[2] == "data":
+                return True
+        except IndexError:
+            return None
+
+        return False
+
     def _is_request_body():
         # type: () -> Optional[bool]
         try:
@@ -282,7 +292,8 @@ def _serialize_node_impl(
                 )
             return None
 
-        if is_databag and global_repr_processors:
+        is_span_attribute = _is_span_attribute()
+        if (is_databag or is_span_attribute) and global_repr_processors:
             hints = {"memo": memo, "remaining_depth": remaining_depth}
             for processor in global_repr_processors:
                 result = processor(obj, hints)

tests/integrations/django/myapp/urls.py

@@ -58,6 +58,7 @@ def path(path, *args, **kwargs):
     path("template-test", views.template_test, name="template_test"),
     path("template-test2", views.template_test2, name="template_test2"),
     path("template-test3", views.template_test3, name="template_test3"),
+    path("template-test4", views.template_test4, name="template_test4"),
     path("postgres-select", views.postgres_select, name="postgres_select"),
     path("postgres-select-slow", views.postgres_select_orm, name="postgres_select_orm"),
     path(

tests/integrations/django/myapp/views.py

@@ -208,6 +208,29 @@ def template_test3(request, *args, **kwargs):
     return render(request, "trace_meta.html", {})
 
 
+@csrf_exempt
+def template_test4(request, *args, **kwargs):
+    User.objects.create_user("john", "lennon@thebeatles.com", "johnpassword")
+    my_queryset = User.objects.all()  # noqa
+
+    template_context = {
+        "user_age": 25,
+        "complex_context": my_queryset,
+        "complex_list": [1, 2, 3, my_queryset],
+        "complex_dict": {
+            "a": 1,
+            "d": my_queryset,
+        },
+        "none_context": None,
+    }
+
+    return TemplateResponse(
+        request,
+        "user_name.html",
+        template_context,
+    )
+
+
 @csrf_exempt
 def postgres_select(request, *args, **kwargs):
     from django.db import connections

tests/integrations/django/test_basic.py

@@ -1,9 +1,10 @@
 import inspect
 import json
 import os
+import pytest
 import re
 import sys
-import pytest
+
 from functools import partial
 from unittest.mock import patch
 
@@ -15,8 +16,8 @@
 from django.core.management import execute_from_command_line
 from django.db.utils import OperationalError, ProgrammingError, DataError
 from django.http.request import RawPostDataException
-from django.utils.functional import SimpleLazyObject
 from django.template.context import make_context
+from django.utils.functional import SimpleLazyObject
 
 try:
     from django.urls import reverse
@@ -956,6 +957,44 @@ def test_render_spans(sentry_init, client, capture_events, render_span_tree):
         assert expected_line in render_span_tree(transaction)
 
 
+@pytest.mark.skipif(DJANGO_VERSION < (1, 9), reason="Requires Django >= 1.9")
+@pytest.mark.forked
+@pytest_mark_django_db_decorator()
+def test_render_spans_queryset_in_data(sentry_init, client, capture_events):
+    sentry_init(
+        integrations=[
+            DjangoIntegration(
+                cache_spans=False,
+                middleware_spans=False,
+                signals_spans=False,
+            )
+        ],
+        traces_sample_rate=1.0,
+    )
+    events = capture_events()
+
+    client.get(reverse("template_test4"))
+
+    (transaction,) = events
+    template_context = transaction["spans"][-1]["data"]["context"]
+
+    assert template_context["user_age"] == 25
+    assert template_context["complex_context"].startswith(
+        "<QuerySet from django.db.models.query at "
+    )
+    assert template_context["complex_dict"]["a"] == 1
+    assert template_context["complex_dict"]["d"].startswith(
+        "<QuerySet from django.db.models.query at "
+    )
+    assert template_context["none_context"] is None
+    assert template_context["complex_list"][0] == 1
+    assert template_context["complex_list"][1] == 2
+    assert template_context["complex_list"][2] == 3
+    assert template_context["complex_list"][3].startswith(
+        "<QuerySet from django.db.models.query at "
+    )
+
+
 if DJANGO_VERSION >= (1, 10):
     EXPECTED_MIDDLEWARE_SPANS = """\
 - op="http.server": description=null