starlette: use test_base to fetch metrics for assertions or filter lo… (#4131)

* starlette: use test_base to fetch metrics for assertions or filter locally

* Update test_starlette_instrumentation.py

* Update test_starlette_instrumentation.py

---------

Co-authored-by: Riccardo Magliocchetti <riccardo.magliocchetti@gmail.com>

Author: anuraaga

instrumentation/opentelemetry-instrumentation-starlette/tests/test_starlette_instrumentation.py

@@ -180,32 +180,24 @@ def test_starlette_metrics(self):
         self._client.get("/foobar")
         self._client.get("/foobar")
         self._client.get("/foobar")
-        metrics_list = self.memory_metrics_reader.get_metrics_data()
         number_data_point_seen = False
         histogram_data_point_seen = False
-        self.assertTrue(len(metrics_list.resource_metrics) == 1)
-        for resource_metric in metrics_list.resource_metrics:
-            self.assertTrue(len(resource_metric.scope_metrics) == 1)
-            for scope_metric in resource_metric.scope_metrics:
-                self.assertEqual(
-                    scope_metric.scope.name,
-                    "opentelemetry.instrumentation.starlette",
-                )
-                self.assertTrue(len(scope_metric.metrics) == 3)
-                for metric in scope_metric.metrics:
-                    self.assertIn(metric.name, _expected_metric_names)
-                    data_points = list(metric.data.data_points)
-                    self.assertEqual(len(data_points), 1)
-                    for point in data_points:
-                        if isinstance(point, HistogramDataPoint):
-                            self.assertEqual(point.count, 3)
-                            histogram_data_point_seen = True
-                        if isinstance(point, NumberDataPoint):
-                            number_data_point_seen = True
-                        for attr in point.attributes:
-                            self.assertIn(
-                                attr, _recommended_attrs[metric.name]
-                            )
+        metrics = self.get_sorted_metrics(
+            scope="opentelemetry.instrumentation.starlette"
+        )
+        self.assertTrue(len(metrics) == 3)
+        for metric in metrics:
+            self.assertIn(metric.name, _expected_metric_names)
+            data_points = list(metric.data.data_points)
+            self.assertEqual(len(data_points), 1)
+            for point in data_points:
+                if isinstance(point, HistogramDataPoint):
+                    self.assertEqual(point.count, 3)
+                    histogram_data_point_seen = True
+                if isinstance(point, NumberDataPoint):
+                    number_data_point_seen = True
+                for attr in point.attributes:
+                    self.assertIn(attr, _recommended_attrs[metric.name])
         self.assertTrue(number_data_point_seen and histogram_data_point_seen)
 
     def test_basic_post_request_metric_success(self):
@@ -233,10 +225,10 @@ def test_basic_post_request_metric_success(self):
         duration = max(round((default_timer() - start) * 1000), 0)
         response_size = int(response.headers.get("content-length"))
         request_size = int(response.request.headers.get("content-length"))
-        metrics_list = self.memory_metrics_reader.get_metrics_data()
-        for metric in (
-            metrics_list.resource_metrics[0].scope_metrics[0].metrics
-        ):
+        metrics = self.get_sorted_metrics(
+            scope="opentelemetry.instrumentation.starlette"
+        )
+        for metric in metrics:
             for point in list(metric.data.data_points):
                 if isinstance(point, HistogramDataPoint):
                     self.assertEqual(point.count, 1)
@@ -262,10 +254,10 @@ def test_metric_for_uninstrment_app_method(self):
         self._instrumentor.uninstrument_app(self._app)
         self._client.get("/foobar")
         self._client.get("/foobar")
-        metrics_list = self.memory_metrics_reader.get_metrics_data()
-        for metric in (
-            metrics_list.resource_metrics[0].scope_metrics[0].metrics
-        ):
+        metrics = self.get_sorted_metrics(
+            scope="opentelemetry.instrumentation.starlette"
+        )
+        for metric in metrics:
             for point in list(metric.data.data_points):
                 if isinstance(point, HistogramDataPoint):
                     self.assertEqual(point.count, 1)
@@ -283,10 +275,10 @@ def test_metric_uninstrument_inherited_by_base(self):
         client.get("/foobar")
         client.get("/foobar")
         client.get("/foobar")
-        metrics_list = self.memory_metrics_reader.get_metrics_data()
-        for metric in (
-            metrics_list.resource_metrics[0].scope_metrics[0].metrics
-        ):
+        metrics = self.get_sorted_metrics(
+            scope="opentelemetry.instrumentation.starlette"
+        )
+        for metric in metrics:
             for point in list(metric.data.data_points):
                 if isinstance(point, HistogramDataPoint):
                     self.assertEqual(point.count, 1)