From 95a5b82ff32d2f84f4c3fe0bbf0c3c2998b80f13 Mon Sep 17 00:00:00 2001
From: Owais Lone <owais@lone.pw>
Date: Mon, 19 Oct 2020 13:50:46 +0530
Subject: [PATCH] Django: Record status, http.status_code and event on
 exception

---
 .../instrumentation/django/middleware.py      | 29 +++++++++----------
 .../tests/test_middleware.py                  | 11 ++++++-
 .../CHANGELOG.md                              |  3 ++
 3 files changed, 26 insertions(+), 17 deletions(-)

diff --git a/instrumentation/opentelemetry-instrumentation-django/src/opentelemetry/instrumentation/django/middleware.py b/instrumentation/opentelemetry-instrumentation-django/src/opentelemetry/instrumentation/django/middleware.py
index 0503d7bbcb6..41343873d04 100644
--- a/instrumentation/opentelemetry-instrumentation-django/src/opentelemetry/instrumentation/django/middleware.py
+++ b/instrumentation/opentelemetry-instrumentation-django/src/opentelemetry/instrumentation/django/middleware.py
@@ -60,6 +60,7 @@ class _DjangoMiddleware(MiddlewareMixin):
     )
     _environ_token = "opentelemetry-instrumentor-django.token"
     _environ_span_key = "opentelemetry-instrumentor-django.span_key"
+    _environ_exception_key = "opentelemetry-instrumentor-django.exception_key"
 
     _excluded_urls = Configuration().DJANGO_EXCLUDED_URLS or []
     if _excluded_urls:
@@ -177,22 +178,11 @@ def process_view(self, request, view_func, *args, **kwargs):
                         span.set_attribute("http.route", route)
 
     def process_exception(self, request, exception):
-        # Django can call this method and process_response later. In order
-        # to avoid __exit__ and detach from being called twice then, the
-        # respective keys are being removed here.
         if self._excluded_urls.url_disabled(request.build_absolute_uri("?")):
             return
 
         if self._environ_activation_key in request.META.keys():
-            request.META[self._environ_activation_key].__exit__(
-                type(exception),
-                exception,
-                getattr(exception, "__traceback__", None),
-            )
-            request.META.pop(self._environ_activation_key)
-
-            detach(request.environ[self._environ_token])
-            request.META.pop(self._environ_token, None)
+            request.META[self._environ_exception_key] = exception
 
     def process_response(self, request, response):
         if self._excluded_urls.url_disabled(request.build_absolute_uri("?")):
@@ -213,9 +203,17 @@ def process_response(self, request, response):
             )
             request.META.pop(self._environ_span_key)
 
-            request.META[self._environ_activation_key].__exit__(
-                None, None, None
-            )
+            exception = request.META.pop(self._environ_exception_key, None)
+            if exception:
+                request.META[self._environ_activation_key].__exit__(
+                    type(exception),
+                    exception,
+                    getattr(exception, "__traceback__", None),
+                )
+            else:
+                request.META[self._environ_activation_key].__exit__(
+                    None, None, None
+                )
             request.META.pop(self._environ_activation_key)
 
         if self._environ_token in request.META.keys():
@@ -231,5 +229,4 @@ def process_response(self, request, response):
                 )
         except Exception as ex:  # pylint: disable=W0703
             _logger.warning("Error recording duration metrics: %s", ex)
-
         return response
diff --git a/instrumentation/opentelemetry-instrumentation-django/tests/test_middleware.py b/instrumentation/opentelemetry-instrumentation-django/tests/test_middleware.py
index 5c034a23af2..4aa794f0de2 100644
--- a/instrumentation/opentelemetry-instrumentation-django/tests/test_middleware.py
+++ b/instrumentation/opentelemetry-instrumentation-django/tests/test_middleware.py
@@ -194,7 +194,7 @@ def test_error(self):
         )
         self.assertEqual(span.kind, SpanKind.SERVER)
         self.assertEqual(
-            span.status.canonical_code, StatusCanonicalCode.UNKNOWN
+            span.status.canonical_code, StatusCanonicalCode.INTERNAL
         )
         self.assertEqual(span.attributes["http.method"], "GET")
         self.assertEqual(
@@ -202,13 +202,22 @@ def test_error(self):
         )
         self.assertEqual(span.attributes["http.route"], "^error/")
         self.assertEqual(span.attributes["http.scheme"], "http")
+        self.assertEqual(span.attributes["http.status_code"], 500)
         self.assertIsNotNone(_django_instrumentor.meter)
         self.assertEqual(len(_django_instrumentor.meter.metrics), 1)
+
+        self.assertEqual(len(span.events), 1)
+        event = span.events[0]
+        self.assertEqual(event.name, "exception")
+        self.assertEqual(event.attributes["exception.type"], "ValueError")
+        self.assertEqual(event.attributes["exception.message"], "error")
+
         recorder = _django_instrumentor.meter.metrics.pop()
         match_key = get_dict_as_key(
             {
                 "http.flavor": "1.1",
                 "http.method": "GET",
+                "http.status_code": "500",
                 "http.url": "http://testserver/error/",
             }
         )
diff --git a/instrumentation/opentelemetry-instrumentation-flask/CHANGELOG.md b/instrumentation/opentelemetry-instrumentation-flask/CHANGELOG.md
index a4641e55b66..bd6ea89cb21 100644
--- a/instrumentation/opentelemetry-instrumentation-flask/CHANGELOG.md
+++ b/instrumentation/opentelemetry-instrumentation-flask/CHANGELOG.md
@@ -2,6 +2,9 @@
 
 ## Unreleased
 
+- Record span status and http.status_code attribute on exception 
+  ([#1257](https://github.com/open-telemetry/opentelemetry-python/pull/1257))
+
 ## Version 0.13b0
 
 Released 2020-09-17