fix(asgi-instrumentation): extract target after running the framework (#1461)

Author: sk-

CHANGELOG.md

@@ -41,6 +41,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
   ([#1424](https://github.com/open-telemetry/opentelemetry-python-contrib/pull/1424))
 - Remove db.name attribute from Redis instrumentation
   ([#1427](https://github.com/open-telemetry/opentelemetry-python-contrib/pull/1427))
+- `opentelemetry-instrumentation-asgi` Fix target extraction for duration metric
+  ([#1461](https://github.com/open-telemetry/opentelemetry-python-contrib/pull/1461))
 - Add grpc.aio instrumentation to package entry points
   ([#1442](https://github.com/open-telemetry/opentelemetry-python-contrib/pull/1442))
 

instrumentation/opentelemetry-instrumentation-asgi/src/opentelemetry/instrumentation/asgi/__init__.py

@@ -542,11 +542,6 @@ async def __call__(self, scope, receive, send):
         )
         duration_attrs = _parse_duration_attrs(attributes)
 
-        target = _collect_target_attribute(scope)
-        if target:
-            active_requests_count_attrs[SpanAttributes.HTTP_TARGET] = target
-            duration_attrs[SpanAttributes.HTTP_TARGET] = target
-
         if scope["type"] == "http":
             self.active_requests_counter.add(1, active_requests_count_attrs)
         try:
@@ -581,6 +576,9 @@ async def __call__(self, scope, receive, send):
                 await self.app(scope, otel_receive, otel_send)
         finally:
             if scope["type"] == "http":
+                target = _collect_target_attribute(scope)
+                if target:
+                    duration_attrs[SpanAttributes.HTTP_TARGET] = target
                 duration = max(round((default_timer() - start) * 1000), 0)
                 self.duration_histogram.record(duration, duration_attrs)
                 self.active_requests_counter.add(

instrumentation/opentelemetry-instrumentation-asgi/tests/test_asgi_middleware.py

@@ -591,8 +591,15 @@ def test_metric_target_attribute(self):
         class TestRoute:
             path_format = expected_target
 
-        self.scope["route"] = TestRoute()
-        app = otel_asgi.OpenTelemetryMiddleware(simple_asgi)
+        async def target_asgi(scope, receive, send):
+            assert isinstance(scope, dict)
+            if scope["type"] == "http":
+                await http_app(scope, receive, send)
+                scope["route"] = TestRoute()
+            else:
+                raise ValueError("websockets not supported")
+
+        app = otel_asgi.OpenTelemetryMiddleware(target_asgi)
         self.seed_app(app)
         self.send_default_request()
 
@@ -601,20 +608,16 @@ class TestRoute:
         for resource_metric in metrics_list.resource_metrics:
             for scope_metrics in resource_metric.scope_metrics:
                 for metric in scope_metrics.metrics:
+                    if metric.name != "http.server.duration":
+                        continue
                     for point in metric.data.data_points:
                         if isinstance(point, HistogramDataPoint):
                             self.assertEqual(
                                 point.attributes["http.target"],
                                 expected_target,
                             )
                             assertions += 1
-                        elif isinstance(point, NumberDataPoint):
-                            self.assertEqual(
-                                point.attributes["http.target"],
-                                expected_target,
-                            )
-                            assertions += 1
-        self.assertEqual(assertions, 2)
+        self.assertEqual(assertions, 1)
 
     def test_no_metric_for_websockets(self):
         self.scope = {

instrumentation/opentelemetry-instrumentation-fastapi/tests/test_fastapi_instrumentation.py

@@ -46,7 +46,7 @@
 ]
 _recommended_attrs = {
     "http.server.active_requests": _active_requests_count_attrs,
-    "http.server.duration": _duration_attrs,
+    "http.server.duration": {*_duration_attrs, SpanAttributes.HTTP_TARGET},
 }
 
 
@@ -218,6 +218,7 @@ def test_basic_metric_success(self):
             "http.server_name": "testserver",
             "net.host.port": 80,
             "http.status_code": 200,
+            "http.target": "/foobar",
         }
         expected_requests_count_attributes = {
             "http.method": "GET",