feat: Django rendering monkey patching (getsentry#957)

Christophe31 · Christophe Narbonne · web-flow · commit dbd7ce89b24d · 2021-01-12T15:32:52.000+01:00
Co-authored-by: Christophe Narbonne &lt;christophe31@intra.logikap.com&gt;
diff --git a/sentry_sdk/integrations/django/__init__.py b/sentry_sdk/integrations/django/__init__.py
@@ -37,7 +37,10 @@
 
 
 from sentry_sdk.integrations.django.transactions import LEGACY_RESOLVER
-from sentry_sdk.integrations.django.templates import get_template_frame_from_exception
+from sentry_sdk.integrations.django.templates import (
+    get_template_frame_from_exception,
+    patch_templates,
+)
 from sentry_sdk.integrations.django.middleware import patch_django_middlewares
 from sentry_sdk.integrations.django.views import patch_views
 
@@ -201,6 +204,7 @@ def _django_queryset_repr(value, hint):
         _patch_channels()
         patch_django_middlewares()
         patch_views()
+        patch_templates()
 
 
 _DRF_PATCHED = False
diff --git a/sentry_sdk/integrations/django/templates.py b/sentry_sdk/integrations/django/templates.py
@@ -1,5 +1,7 @@
 from django.template import TemplateSyntaxError
+from django import VERSION as DJANGO_VERSION
 
+from sentry_sdk import _functools, Hub
 from sentry_sdk._types import MYPY
 
 if MYPY:
@@ -40,6 +42,50 @@ def get_template_frame_from_exception(exc_value):
     return None
 
 
+def patch_templates():
+    # type: () -> None
+    from django.template.response import SimpleTemplateResponse
+    from sentry_sdk.integrations.django import DjangoIntegration
+
+    real_rendered_content = SimpleTemplateResponse.rendered_content
+
+    @property  # type: ignore
+    def rendered_content(self):
+        # type: (SimpleTemplateResponse) -> str
+        hub = Hub.current
+        if hub.get_integration(DjangoIntegration) is None:
+            return real_rendered_content.fget(self)
+
+        with hub.start_span(
+            op="django.template.render", description=self.template_name
+        ) as span:
+            span.set_data("context", self.context_data)
+            return real_rendered_content.fget(self)
+
+    SimpleTemplateResponse.rendered_content = rendered_content
+
+    if DJANGO_VERSION < (1, 7):
+        return
+    import django.shortcuts
+
+    real_render = django.shortcuts.render
+
+    @_functools.wraps(real_render)
+    def render(request, template_name, context=None, *args, **kwargs):
+        # type: (django.http.HttpRequest, str, Optional[Dict[str, Any]], *Any, **Any) -> django.http.HttpResponse
+        hub = Hub.current
+        if hub.get_integration(DjangoIntegration) is None:
+            return real_render(request, template_name, context, *args, **kwargs)
+
+        with hub.start_span(
+            op="django.template.render", description=template_name
+        ) as span:
+            span.set_data("context", context)
+            return real_render(request, template_name, context, *args, **kwargs)
+
+    django.shortcuts.render = render
+
+
 def _get_template_frame_from_debug(debug):
     # type: (Dict[str, Any]) -> Dict[str, Any]
     if debug is None:
diff --git a/tests/integrations/django/myapp/templates/user_name.html b/tests/integrations/django/myapp/templates/user_name.html
@@ -0,0 +1 @@
+{{ request.user }}: {{ user_age }}
diff --git a/tests/integrations/django/myapp/urls.py b/tests/integrations/django/myapp/urls.py
@@ -45,6 +45,8 @@ def path(path, *args, **kwargs):
     ),
     path("post-echo", views.post_echo, name="post_echo"),
     path("template-exc", views.template_exc, name="template_exc"),
+    path("template-test", views.template_test, name="template_test"),
+    path("template-test2", views.template_test2, name="template_test2"),
     path(
         "permission-denied-exc",
         views.permission_denied_exc,
diff --git a/tests/integrations/django/myapp/views.py b/tests/integrations/django/myapp/views.py
@@ -4,6 +4,7 @@
 from django.core.exceptions import PermissionDenied
 from django.http import HttpResponse, HttpResponseNotFound, HttpResponseServerError
 from django.shortcuts import render
+from django.template.response import TemplateResponse
 from django.utils.decorators import method_decorator
 from django.views.decorators.csrf import csrf_exempt
 from django.views.generic import ListView
@@ -114,6 +115,16 @@ def template_exc(request, *args, **kwargs):
     return render(request, "error.html")
 
 
+@csrf_exempt
+def template_test(request, *args, **kwargs):
+    return render(request, "user_name.html", {"user_age": 20})
+
+
+@csrf_exempt
+def template_test2(request, *args, **kwargs):
+    return TemplateResponse(request, "user_name.html", {"user_age": 25})
+
+
 @csrf_exempt
 def permission_denied_exc(*args, **kwargs):
     raise PermissionDenied("bye")
diff --git a/tests/integrations/django/test_basic.py b/tests/integrations/django/test_basic.py
@@ -518,6 +518,25 @@ def test_does_not_capture_403(sentry_init, client, capture_events, endpoint):
     assert not events
 
 
+def test_render_spans(sentry_init, client, capture_events, render_span_tree):
+    sentry_init(
+        integrations=[DjangoIntegration()],
+        traces_sample_rate=1.0,
+    )
+    views_urls = [reverse("template_test2")]
+    if DJANGO_VERSION >= (1, 7):
+        views_urls.append(reverse("template_test"))
+
+    for url in views_urls:
+        events = capture_events()
+        _content, status, _headers = client.get(url)
+        transaction = events[0]
+        assert (
+            '- op="django.template.render": description="user_name.html"'
+            in render_span_tree(transaction)
+        )
+
+
 def test_middleware_spans(sentry_init, client, capture_events, render_span_tree):
     sentry_init(
         integrations=[DjangoIntegration()],
