opentelemetry-instrumentation-flask: add explicit http duration buckets for stable semconv (open-telemetry#3523)

* opentelemetry-instrumentation-flask: add explicit http duration buckets for stable semconv

* Update CHANGELOG.md

* Fix pylint

Author: xrmx

CHANGELOG.md

@@ -15,6 +15,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 - `opentelemetry-instrumentation-fastapi`: fix wrapping of middlewares
   ([#3012](https://github.com/open-telemetry/opentelemetry-python-contrib/pull/3012))
+- `opentelemetry-instrumentation-flask`: proper bucket boundaries in stable semconv http duration
+  ([#3523](https://github.com/open-telemetry/opentelemetry-python-contrib/pull/3523))
 - `opentelemetry-instrumentation-django`: proper bucket boundaries in stable semconv http duration
   ([#3524](https://github.com/open-telemetry/opentelemetry-python-contrib/pull/3524))
 - `opentelemetry-instrumentation-grpc`: support non-list interceptors

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

@@ -257,6 +257,7 @@ def response_hook(span: Span, status: str, response_headers: List):
 import opentelemetry.instrumentation.wsgi as otel_wsgi
 from opentelemetry import context, trace
 from opentelemetry.instrumentation._semconv import (
+    HTTP_DURATION_HISTOGRAM_BUCKETS_NEW,
     _get_schema_url,
     _OpenTelemetrySemanticConventionStability,
     _OpenTelemetryStabilitySignalType,
@@ -583,6 +584,7 @@ def __init__(self, *args, **kwargs):
                 name=HTTP_SERVER_REQUEST_DURATION,
                 unit="s",
                 description="Duration of HTTP server requests.",
+                explicit_bucket_boundaries_advisory=HTTP_DURATION_HISTOGRAM_BUCKETS_NEW,
             )
         active_requests_counter = meter.create_up_down_counter(
             name=MetricInstruments.HTTP_SERVER_ACTIVE_REQUESTS,
@@ -716,6 +718,7 @@ def instrument_app(
                     name=HTTP_SERVER_REQUEST_DURATION,
                     unit="s",
                     description="Duration of HTTP server requests.",
+                    explicit_bucket_boundaries_advisory=HTTP_DURATION_HISTOGRAM_BUCKETS_NEW,
                 )
             active_requests_counter = meter.create_up_down_counter(
                 name=MetricInstruments.HTTP_SERVER_ACTIVE_REQUESTS,

instrumentation/opentelemetry-instrumentation-flask/tests/test_programmatic.py

@@ -20,6 +20,7 @@
 
 from opentelemetry import trace
 from opentelemetry.instrumentation._semconv import (
+    HTTP_DURATION_HISTOGRAM_BUCKETS_NEW,
     OTEL_SEMCONV_STABILITY_OPT_IN,
     _OpenTelemetrySemanticConventionStability,
     _server_active_requests_count_attrs_new,
@@ -522,6 +523,10 @@ def test_flask_metrics_new_semconv(self):
                             self.assertAlmostEqual(
                                 duration_s, point.sum, places=1
                             )
+                            self.assertEqual(
+                                point.explicit_bounds,
+                                HTTP_DURATION_HISTOGRAM_BUCKETS_NEW,
+                            )
                             histogram_data_point_seen = True
                         if isinstance(point, NumberDataPoint):
                             number_data_point_seen = True
@@ -552,8 +557,12 @@ def test_flask_metric_values(self):
                             self.assertEqual(point.value, 0)
 
     def _assert_basic_metric(
-        self, expected_duration_attributes, expected_requests_count_attributes
+        self,
+        expected_duration_attributes,
+        expected_requests_count_attributes,
+        expected_histogram_explicit_bounds=None,
     ):
+        # pylint: disable=too-many-nested-blocks
         metrics_list = self.memory_metrics_reader.get_metrics_data()
         for resource_metric in metrics_list.resource_metrics:
             for scope_metrics in resource_metric.scope_metrics:
@@ -564,6 +573,11 @@ def _assert_basic_metric(
                                 expected_duration_attributes,
                                 dict(point.attributes),
                             )
+                            if expected_histogram_explicit_bounds is not None:
+                                self.assertEqual(
+                                    expected_histogram_explicit_bounds,
+                                    point.explicit_bounds,
+                                )
                             self.assertEqual(point.count, 1)
                         elif isinstance(point, NumberDataPoint):
                             self.assertDictEqual(
@@ -613,6 +627,7 @@ def test_basic_metric_success_new_semconv(self):
         self._assert_basic_metric(
             expected_duration_attributes,
             expected_requests_count_attributes,
+            expected_histogram_explicit_bounds=HTTP_DURATION_HISTOGRAM_BUCKETS_NEW,
         )
 
     def test_basic_metric_nonstandard_http_method_success(self):
@@ -654,6 +669,7 @@ def test_basic_metric_nonstandard_http_method_success_new_semconv(self):
         self._assert_basic_metric(
             expected_duration_attributes,
             expected_requests_count_attributes,
+            expected_histogram_explicit_bounds=HTTP_DURATION_HISTOGRAM_BUCKETS_NEW,
         )
 
     @patch.dict(
@@ -679,6 +695,7 @@ def test_basic_metric_nonstandard_http_method_allowed_success_new_semconv(
         self._assert_basic_metric(
             expected_duration_attributes,
             expected_requests_count_attributes,
+            expected_histogram_explicit_bounds=HTTP_DURATION_HISTOGRAM_BUCKETS_NEW,
         )
 
     def test_metric_uninstrument(self):