Select histogram aggregation with environment variables

CHANGELOG.md

@@ -7,6 +7,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## Unreleased
 
+- Select histogram aggregation with an environment variable
+  ([#3265](https://github.com/open-telemetry/opentelemetry-python/pull/3265))
 - Move Protobuf encoding to its own package
   ([#3169](https://github.com/open-telemetry/opentelemetry-python/pull/3169))
 - Add experimental feature to detect resource detectors in auto instrumentation

exporter/opentelemetry-exporter-otlp-proto-common/src/opentelemetry/exporter/otlp/proto/common/_internal/metrics_encoder/__init__.py

@@ -13,9 +13,27 @@
 # limitations under the License.
 import logging
 
+from opentelemetry.sdk.metrics.export import (
+    MetricExporter,
+)
+from os import environ
+from opentelemetry.sdk.metrics import (
+    Counter,
+    Histogram,
+    ObservableCounter,
+    ObservableGauge,
+    ObservableUpDownCounter,
+    UpDownCounter,
+)
 from opentelemetry.exporter.otlp.proto.common._internal import (
     _encode_attributes,
 )
+from opentelemetry.sdk.environment_variables import (
+    OTEL_EXPORTER_OTLP_METRICS_TEMPORALITY_PREFERENCE,
+)
+from opentelemetry.sdk.metrics.export import (
+    AggregationTemporality,
+)
 from opentelemetry.proto.collector.metrics.v1.metrics_service_pb2 import (
     ExportMetricsServiceRequest,
 )
@@ -24,17 +42,118 @@
 from opentelemetry.sdk.metrics.export import (
     MetricsData,
     Gauge,
-    Histogram,
+    Histogram as HistogramType,
     Sum,
     ExponentialHistogram as ExponentialHistogramType,
 )
+from typing import Dict
 from opentelemetry.proto.resource.v1.resource_pb2 import (
     Resource as PB2Resource,
 )
+from opentelemetry.sdk.environment_variables import (
+    OTEL_EXPORTER_OTLP_METRICS_DEFAULT_HISTOGRAM_AGGREGATION,
+)
+from opentelemetry.sdk.metrics.view import (
+    ExponentialBucketHistogramAggregation,
+    ExplicitBucketHistogramAggregation,
+)
 
 _logger = logging.getLogger(__name__)
 
 
+class OTLPMetricExporterMixin:
+    def _common_configuration(
+        self,
+        preferred_temporality: Dict[type, AggregationTemporality] = None,
+    ) -> None:
+
+        instrument_class_temporality = {}
+
+        otel_exporter_otlp_metrics_temporality_preference = (
+            environ.get(
+                OTEL_EXPORTER_OTLP_METRICS_TEMPORALITY_PREFERENCE,
+                "CUMULATIVE",
+            )
+            .upper()
+            .strip()
+        )
+
+        if otel_exporter_otlp_metrics_temporality_preference == "DELTA":
+            instrument_class_temporality = {
+                Counter: AggregationTemporality.DELTA,
+                UpDownCounter: AggregationTemporality.CUMULATIVE,
+                Histogram: AggregationTemporality.DELTA,
+                ObservableCounter: AggregationTemporality.DELTA,
+                ObservableUpDownCounter: AggregationTemporality.CUMULATIVE,
+                ObservableGauge: AggregationTemporality.CUMULATIVE,
+            }
+
+        elif otel_exporter_otlp_metrics_temporality_preference == "LOWMEMORY":
+            instrument_class_temporality = {
+                Counter: AggregationTemporality.DELTA,
+                UpDownCounter: AggregationTemporality.CUMULATIVE,
+                Histogram: AggregationTemporality.DELTA,
+                ObservableCounter: AggregationTemporality.CUMULATIVE,
+                ObservableUpDownCounter: AggregationTemporality.CUMULATIVE,
+                ObservableGauge: AggregationTemporality.CUMULATIVE,
+            }
+
+        else:
+            if otel_exporter_otlp_metrics_temporality_preference != (
+                "CUMULATIVE"
+            ):
+                _logger.warning(
+                    "Unrecognized OTEL_EXPORTER_METRICS_TEMPORALITY_PREFERENCE"
+                    " value found: "
+                    f"{otel_exporter_otlp_metrics_temporality_preference}, "
+                    "using CUMULATIVE"
+                )
+            instrument_class_temporality = {
+                Counter: AggregationTemporality.CUMULATIVE,
+                UpDownCounter: AggregationTemporality.CUMULATIVE,
+                Histogram: AggregationTemporality.CUMULATIVE,
+                ObservableCounter: AggregationTemporality.CUMULATIVE,
+                ObservableUpDownCounter: AggregationTemporality.CUMULATIVE,
+                ObservableGauge: AggregationTemporality.CUMULATIVE,
+            }
+
+        instrument_class_temporality.update(preferred_temporality or {})
+
+        otel_exporter_otlp_metrics_default_histogram_aggregation = environ.get(
+            OTEL_EXPORTER_OTLP_METRICS_DEFAULT_HISTOGRAM_AGGREGATION,
+            "explicit_bucket_histogram",
+        )
+
+        if otel_exporter_otlp_metrics_default_histogram_aggregation == (
+            "base2_exponential_bucket_histogram"
+        ):
+
+            histogram_aggregation_type = ExponentialBucketHistogramAggregation
+
+        else:
+
+            if otel_exporter_otlp_metrics_default_histogram_aggregation != (
+                "explicit_bucket_histogram"
+            ):
+
+                _logger.warning(
+                    (
+                        "Invalid value for %s: %s, using explicit bucket "
+                        "histogram aggregation"
+                    ),
+                    OTEL_EXPORTER_OTLP_METRICS_DEFAULT_HISTOGRAM_AGGREGATION,
+                    otel_exporter_otlp_metrics_default_histogram_aggregation,
+                )
+
+            histogram_aggregation_type = ExplicitBucketHistogramAggregation
+
+        MetricExporter.__init__(
+            self,
+            preferred_temporality=instrument_class_temporality,
+            preferred_aggregation={Histogram: histogram_aggregation_type()},
+        )
+
+
 def encode_metrics(data: MetricsData) -> ExportMetricsServiceRequest:
     resource_metrics_dict = {}
 
@@ -85,7 +204,7 @@ def encode_metrics(data: MetricsData) -> ExportMetricsServiceRequest:
                             pt.as_double = data_point.value
                         pb2_metric.gauge.data_points.append(pt)
 
-                elif isinstance(metric.data, Histogram):
+                elif isinstance(metric.data, HistogramType):
                     for data_point in metric.data.data_points:
                         pt = pb2.HistogramDataPoint(
                             attributes=_encode_attributes(

exporter/opentelemetry-exporter-otlp-proto-grpc/src/opentelemetry/exporter/otlp/proto/grpc/metric_exporter/__init__.py

@@ -47,15 +47,6 @@
     OTEL_EXPORTER_OTLP_METRICS_HEADERS,
     OTEL_EXPORTER_OTLP_METRICS_INSECURE,
     OTEL_EXPORTER_OTLP_METRICS_TIMEOUT,
-    OTEL_EXPORTER_OTLP_METRICS_TEMPORALITY_PREFERENCE,
-)
-from opentelemetry.sdk.metrics import (
-    Counter,
-    Histogram,
-    ObservableCounter,
-    ObservableGauge,
-    ObservableUpDownCounter,
-    UpDownCounter,
 )
 from opentelemetry.sdk.metrics.export import (
     AggregationTemporality,
@@ -73,13 +64,17 @@
     Sum,
     ExponentialHistogram as ExponentialHistogramType,
 )
+from opentelemetry.exporter.otlp.proto.common._internal.metrics_encoder import (
+    OTLPMetricExporterMixin,
+)
 
 _logger = getLogger(__name__)
 
 
 class OTLPMetricExporter(
     MetricExporter,
     OTLPExporterMixin[Metric, ExportMetricsServiceRequest, MetricExportResult],
+    OTLPMetricExporterMixin,
 ):
     """OTLP metric exporter
 
@@ -132,63 +127,7 @@ def __init__(
             else compression
         )
 
-        instrument_class_temporality = {}
-
-        otel_exporter_otlp_metrics_temporality_preference = (
-            environ.get(
-                OTEL_EXPORTER_OTLP_METRICS_TEMPORALITY_PREFERENCE,
-                "CUMULATIVE",
-            )
-            .upper()
-            .strip()
-        )
-
-        if otel_exporter_otlp_metrics_temporality_preference == "DELTA":
-            instrument_class_temporality = {
-                Counter: AggregationTemporality.DELTA,
-                UpDownCounter: AggregationTemporality.CUMULATIVE,
-                Histogram: AggregationTemporality.DELTA,
-                ObservableCounter: AggregationTemporality.DELTA,
-                ObservableUpDownCounter: AggregationTemporality.CUMULATIVE,
-                ObservableGauge: AggregationTemporality.CUMULATIVE,
-            }
-
-        elif otel_exporter_otlp_metrics_temporality_preference == "LOWMEMORY":
-            instrument_class_temporality = {
-                Counter: AggregationTemporality.DELTA,
-                UpDownCounter: AggregationTemporality.CUMULATIVE,
-                Histogram: AggregationTemporality.DELTA,
-                ObservableCounter: AggregationTemporality.CUMULATIVE,
-                ObservableUpDownCounter: AggregationTemporality.CUMULATIVE,
-                ObservableGauge: AggregationTemporality.CUMULATIVE,
-            }
-
-        else:
-            if otel_exporter_otlp_metrics_temporality_preference != (
-                "CUMULATIVE"
-            ):
-                _logger.warning(
-                    "Unrecognized OTEL_EXPORTER_METRICS_TEMPORALITY_PREFERENCE"
-                    " value found: "
-                    f"{otel_exporter_otlp_metrics_temporality_preference}, "
-                    "using CUMULATIVE"
-                )
-            instrument_class_temporality = {
-                Counter: AggregationTemporality.CUMULATIVE,
-                UpDownCounter: AggregationTemporality.CUMULATIVE,
-                Histogram: AggregationTemporality.CUMULATIVE,
-                ObservableCounter: AggregationTemporality.CUMULATIVE,
-                ObservableUpDownCounter: AggregationTemporality.CUMULATIVE,
-                ObservableGauge: AggregationTemporality.CUMULATIVE,
-            }
-
-        instrument_class_temporality.update(preferred_temporality or {})
-
-        MetricExporter.__init__(
-            self,
-            preferred_temporality=instrument_class_temporality,
-            preferred_aggregation=preferred_aggregation,
-        )
+        self._common_configuration(preferred_temporality)
 
         OTLPExporterMixin.__init__(
             self,

exporter/opentelemetry-exporter-otlp-proto-grpc/tests/test_otlp_metrics_exporter.py

@@ -44,6 +44,7 @@
     OTEL_EXPORTER_OTLP_COMPRESSION,
     OTEL_EXPORTER_OTLP_METRICS_CERTIFICATE,
     OTEL_EXPORTER_OTLP_METRICS_COMPRESSION,
+    OTEL_EXPORTER_OTLP_METRICS_DEFAULT_HISTOGRAM_AGGREGATION,
     OTEL_EXPORTER_OTLP_METRICS_ENDPOINT,
     OTEL_EXPORTER_OTLP_METRICS_HEADERS,
     OTEL_EXPORTER_OTLP_METRICS_INSECURE,
@@ -68,6 +69,10 @@
     ResourceMetrics,
     ScopeMetrics,
 )
+from opentelemetry.sdk.metrics.view import (
+    ExplicitBucketHistogramAggregation,
+    ExponentialBucketHistogramAggregation,
+)
 from opentelemetry.sdk.resources import Resource
 from opentelemetry.sdk.util.instrumentation import (
     InstrumentationScope as SDKInstrumentationScope,
@@ -872,6 +877,57 @@ def test_aggregation_temporality(self):
                 AggregationTemporality.CUMULATIVE,
             )
 
+    def test_exponential_explicit_bucket_histogram(self):
+
+        self.assertIsInstance(
+            # pylint: disable=protected-access
+            OTLPMetricExporter()._preferred_aggregation[Histogram],
+            ExplicitBucketHistogramAggregation,
+        )
+
+        with patch.dict(
+            environ,
+            {
+                OTEL_EXPORTER_OTLP_METRICS_DEFAULT_HISTOGRAM_AGGREGATION: "base2_exponential_bucket_histogram"
+            },
+        ):
+            self.assertIsInstance(
+                # pylint: disable=protected-access
+                OTLPMetricExporter()._preferred_aggregation[Histogram],
+                ExponentialBucketHistogramAggregation,
+            )
+
+        with patch.dict(
+            environ,
+            {OTEL_EXPORTER_OTLP_METRICS_DEFAULT_HISTOGRAM_AGGREGATION: "abc"},
+        ):
+            with self.assertLogs(level=WARNING) as log:
+                self.assertIsInstance(
+                    # pylint: disable=protected-access
+                    OTLPMetricExporter()._preferred_aggregation[Histogram],
+                    ExplicitBucketHistogramAggregation,
+                )
+            self.assertIn(
+                (
+                    "Invalid value for OTEL_EXPORTER_OTLP_METRICS_DEFAULT_"
+                    "HISTOGRAM_AGGREGATION: abc, using explicit bucket "
+                    "histogram aggregation"
+                ),
+                log.output[0],
+            )
+
+        with patch.dict(
+            environ,
+            {
+                OTEL_EXPORTER_OTLP_METRICS_DEFAULT_HISTOGRAM_AGGREGATION: "explicit_bucket_histogram"
+            },
+        ):
+            self.assertIsInstance(
+                # pylint: disable=protected-access
+                OTLPMetricExporter()._preferred_aggregation[Histogram],
+                ExplicitBucketHistogramAggregation,
+            )
+
 
 def _resource_metrics(
     index: int, scope_metrics: List[ScopeMetrics]