exporter/metric: Add support to export Distribution with Exemplars and Exponential Histograms.

example/metric/exponential_histogram/example.go

@@ -0,0 +1,322 @@
+// Copyright 2020 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package main
+
+import (
+	"context"
+	"fmt"
+	"log"
+	"math/rand"
+	"os"
+	"os/signal"
+	"syscall"
+	"time"
+
+	"gonum.org/v1/gonum/stat"
+	"gonum.org/v1/gonum/stat/distuv"
+
+	mexporter "github.com/GoogleCloudPlatform/opentelemetry-operations-go/exporter/metric"
+
+	"go.opentelemetry.io/contrib/detectors/gcp"
+	"go.opentelemetry.io/otel/attribute"
+	"go.opentelemetry.io/otel/metric"
+	sdkmetric "go.opentelemetry.io/otel/sdk/metric"
+	"go.opentelemetry.io/otel/sdk/metric/metricdata"
+	"go.opentelemetry.io/otel/sdk/resource"
+	semconv "go.opentelemetry.io/otel/semconv/v1.21.0"
+)
+
+func workloadMetricsPrefixFormatter(d metricdata.Metrics) string {
+	return fmt.Sprintf("custom.googleapis.com/%s", d.Name)
+}
+
+func main() {
+	ctx := context.Background()
+
+	// Resource for GCP and SDK detectors
+	res, err := resource.New(ctx,
+		resource.WithDetectors(gcp.NewDetector()),
+		resource.WithTelemetrySDK(),
+		resource.WithAttributes(
+			semconv.ServiceNameKey.String("example-application"),
+		),
+	)
+	if err != nil {
+		log.Fatalf("resource.New: %v", err)
+	}
+
+	// Create exporter pipeline
+	exporter, err := mexporter.New(
+		mexporter.WithMetricDescriptorTypeFormatter(workloadMetricsPrefixFormatter),
+	)
+	if err != nil {
+		log.Fatalf("Failed to create exporter: %v", err)
+	}
+
+	clabels := []attribute.KeyValue{attribute.Key("key").String("value")}
+	defaultBuckets := []float64{0, 5, 10, 25, 50, 75, 100, 250, 500, 1000}
+	linearBuckets := make([]float64, 35)
+	for i := 0; i < 35; i++ {
+		linearBuckets[i] = float64(i*10 + 10)
+	}
+
+	viewLatencyA := sdkmetric.NewView(
+		sdkmetric.Instrument{
+			Name: "latency",
+		},
+		sdkmetric.Stream{
+			Name: "latency_a",
+			Aggregation: sdkmetric.AggregationBase2ExponentialHistogram{
+				MaxSize:  160,
+				MaxScale: 20,
+			},
+		},
+	)
+
+	viewLatencyB := sdkmetric.NewView(
+		sdkmetric.Instrument{
+			Name: "latency",
+		},
+		sdkmetric.Stream{
+			Name: "latency_b",
+			Aggregation: sdkmetric.AggregationExplicitBucketHistogram{
+				Boundaries: linearBuckets,
+			},
+		},
+	)
+
+	viewLatencyC := sdkmetric.NewView(
+		sdkmetric.Instrument{
+			Name: "latency",
+		},
+		sdkmetric.Stream{
+			Name: "latency_c",
+			Aggregation: sdkmetric.AggregationExplicitBucketHistogram{
+				Boundaries: defaultBuckets,
+			},
+		},
+	)
+
+	viewLatencyShiftedA := sdkmetric.NewView(
+		sdkmetric.Instrument{
+			Name: "latency_shifted",
+		},
+		sdkmetric.Stream{
+			Name: "latency_shifted_a",
+			Aggregation: sdkmetric.AggregationBase2ExponentialHistogram{
+				MaxSize:  160,
+				MaxScale: 20,
+			},
+		},
+	)
+
+	viewLatencyShiftedB := sdkmetric.NewView(
+		sdkmetric.Instrument{
+			Name: "latency_shifted",
+		},
+		sdkmetric.Stream{
+			Name: "latency_shifted_b",
+			Aggregation: sdkmetric.AggregationExplicitBucketHistogram{
+				Boundaries: linearBuckets,
+			},
+		},
+	)
+
+	viewLatencyShiftedC := sdkmetric.NewView(
+		sdkmetric.Instrument{
+			Name: "latency_shifted",
+		},
+		sdkmetric.Stream{
+			Name: "latency_shifted_c",
+			Aggregation: sdkmetric.AggregationExplicitBucketHistogram{
+				Boundaries: defaultBuckets,
+			},
+		},
+	)
+
+	viewLatencyMultimodalA := sdkmetric.NewView(
+		sdkmetric.Instrument{
+			Name: "latency_multimodal",
+		},
+		sdkmetric.Stream{
+			Name: "latency_multimodal_a",
+			Aggregation: sdkmetric.AggregationBase2ExponentialHistogram{
+				MaxSize:  160,
+				MaxScale: 20,
+			},
+		},
+	)
+
+	viewLatencyMultimodalB := sdkmetric.NewView(
+		sdkmetric.Instrument{
+			Name: "latency_multimodal",
+		},
+		sdkmetric.Stream{
+			Name: "latency_multimodal_b",
+			Aggregation: sdkmetric.AggregationExplicitBucketHistogram{
+				Boundaries: linearBuckets,
+			},
+		},
+	)
+
+	viewLatencyMultimodalC := sdkmetric.NewView(
+		sdkmetric.Instrument{
+			Name: "latency_multimodal",
+		},
+		sdkmetric.Stream{
+			Name: "latency_multimodal_c",
+			Aggregation: sdkmetric.AggregationExplicitBucketHistogram{
+				Boundaries: defaultBuckets,
+			},
+		},
+	)
+
+	// initialize a MeterProvider with that periodically exports to the GCP exporter.
+	provider := sdkmetric.NewMeterProvider(
+		sdkmetric.WithView(viewLatencyA),
+		sdkmetric.WithView(viewLatencyB),
+		sdkmetric.WithView(viewLatencyC),
+		sdkmetric.WithView(viewLatencyShiftedA),
+		sdkmetric.WithView(viewLatencyShiftedB),
+		sdkmetric.WithView(viewLatencyShiftedC),
+		sdkmetric.WithView(viewLatencyMultimodalA),
+		sdkmetric.WithView(viewLatencyMultimodalB),
+		sdkmetric.WithView(viewLatencyMultimodalC),
+		sdkmetric.WithReader(
+			sdkmetric.NewPeriodicReader(
+				exporter,
+				sdkmetric.WithInterval(10*time.Second),
+			),
+		),
+		sdkmetric.WithResource(res),
+	)
+	defer func() {
+		if err = provider.Shutdown(ctx); err != nil {
+			log.Fatalf("failed to shutdown meter provider: %v", err)
+		}
+	}()
+
+	// Create a meter with which we will record metrics for our package.
+	meter := provider.Meter("github.com/GoogleCloudPlatform/opentelemetry-operations-go/example/metric")
+
+	_, err = meter.Float64ObservableGauge(
+		"latency",
+		metric.WithDescription(
+			"Latency",
+		),
+		metric.WithUnit("ms"),
+		metric.WithFloat64Callback(func(_ context.Context, o metric.Float64Observer) error {
+			points := 1000
+
+			// Create a log normal distribution to simulate latency
+			// from server response.
+			dist := distuv.LogNormal{
+				Mu:    3.5,
+				Sigma: .5,
+			}
+
+			data := make([]float64, points)
+
+			// Draw some random values from the log normal distribution
+			for i := range data {
+				data[i] = dist.Rand()
+
+				// Gauge metric observation
+				o.Observe(data[i], metric.WithAttributes(clabels...))
+			}
+			mean, std := stat.MeanStdDev(data, nil)
+			log.Printf("Sent Latency Data (Original Distribution): #points %d , mean %v, sdv %v", points, mean, std)
+			return nil
+		}),
+	)
+
+	_, err = meter.Float64ObservableGauge(
+		"latency_shifted",
+		metric.WithDescription(
+			"Latency Shifted",
+		),
+		metric.WithUnit("ms"),
+		metric.WithFloat64Callback(func(_ context.Context, o metric.Float64Observer) error {
+			points := 1000
+
+			// Create a log normal distribution to simulate latency
+			// from server response.
+			dist := distuv.LogNormal{
+				Mu:    5.5,
+				Sigma: .5,
+			}
+
+			data := make([]float64, points)
+
+			// Draw some random values from the log normal distribution
+			for i := range data {
+				data[i] = dist.Rand()
+
+				// Gauge metric observation
+				o.Observe(data[i], metric.WithAttributes(clabels...))
+			}
+			mean, std := stat.MeanStdDev(data, nil)
+			log.Printf("Sent Latency Data (Shifted Distribution): #points %d , mean %v, sdv %v", points, mean, std)
+			return nil
+		}),
+	)
+
+	_, err = meter.Float64ObservableGauge(
+		"latency_multimodal",
+		metric.WithDescription(
+			"Latency Multimodal",
+		),
+		metric.WithUnit("ms"),
+		metric.WithFloat64Callback(func(_ context.Context, o metric.Float64Observer) error {
+			points := 1000
+
+			// Create a multimodal normal
+			dist1 := distuv.LogNormal{
+				Mu:    3.5,
+				Sigma: .5,
+			}
+			dist2 := distuv.LogNormal{
+				Mu:    5.5,
+				Sigma: .5,
+			}
+
+			data := make([]float64, points)
+
+			// Draw some random values from the log normal distribution
+			for i := range data {
+				if rand.Float64() < .5 {
+					data[i] = dist1.Rand()
+				} else {
+					data[i] = dist2.Rand()
+				}
+
+				// Gauge metric observation
+				o.Observe(data[i], metric.WithAttributes(clabels...))
+			}
+			mean, std := stat.MeanStdDev(data, nil)
+			log.Printf("Sent Latency Data (Multimodal Distribution): #points %d , mean %v, sdv %v", points, mean, std)
+			return nil
+		}),
+	)
+
+	if err != nil {
+		log.Fatalf("Failed to create gauge: %v", err)
+	}
+
+	// Wait for interrupt
+	var stopChan = make(chan os.Signal, 2)
+	signal.Notify(stopChan, os.Interrupt, syscall.SIGTERM, syscall.SIGINT)
+	<-stopChan
+}

example/metric/exponential_histogram/go.mod

@@ -0,0 +1,47 @@
+module github.com/GoogleCloudPlatform/opentelemetry-operations-go/example/metric/sdk
+
+go 1.20
+
+require (
+	github.com/GoogleCloudPlatform/opentelemetry-operations-go/exporter/metric v0.45.0
+	go.opentelemetry.io/contrib/detectors/gcp v1.24.0
+	go.opentelemetry.io/otel v1.24.0
+	go.opentelemetry.io/otel/metric v1.24.0
+	go.opentelemetry.io/otel/sdk v1.24.0
+	go.opentelemetry.io/otel/sdk/metric v1.24.0
+	gonum.org/v1/gonum v0.14.0
+)
+
+require (
+	cloud.google.com/go/compute v1.23.0 // indirect
+	cloud.google.com/go/compute/metadata v0.2.3 // indirect
+	cloud.google.com/go/monitoring v1.15.1 // indirect
+	github.com/GoogleCloudPlatform/opentelemetry-operations-go/detectors/gcp v1.21.0 // indirect
+	github.com/GoogleCloudPlatform/opentelemetry-operations-go/internal/resourcemapping v0.45.0 // indirect
+	github.com/go-logr/logr v1.4.1 // indirect
+	github.com/go-logr/stdr v1.2.2 // indirect
+	github.com/golang/groupcache v0.0.0-20210331224755-41bb18bfe9da // indirect
+	github.com/golang/protobuf v1.5.3 // indirect
+	github.com/google/go-cmp v0.6.0 // indirect
+	github.com/google/s2a-go v0.1.4 // indirect
+	github.com/googleapis/enterprise-certificate-proxy v0.2.3 // indirect
+	github.com/googleapis/gax-go/v2 v2.11.0 // indirect
+	go.opencensus.io v0.24.0 // indirect
+	go.opentelemetry.io/otel/trace v1.24.0 // indirect
+	golang.org/x/crypto v0.17.0 // indirect
+	golang.org/x/exp v0.0.0-20230321023759-10a507213a29 // indirect
+	golang.org/x/net v0.17.0 // indirect
+	golang.org/x/oauth2 v0.10.0 // indirect
+	golang.org/x/sync v0.3.0 // indirect
+	golang.org/x/sys v0.17.0 // indirect
+	golang.org/x/text v0.14.0 // indirect
+	google.golang.org/api v0.126.0 // indirect
+	google.golang.org/appengine v1.6.7 // indirect
+	google.golang.org/genproto v0.0.0-20230731193218-e0aa005b6bdf // indirect
+	google.golang.org/genproto/googleapis/api v0.0.0-20230726155614-23370e0ffb3e // indirect
+	google.golang.org/genproto/googleapis/rpc v0.0.0-20230731190214-cbb8c96f2d6d // indirect
+	google.golang.org/grpc v1.58.3 // indirect
+	google.golang.org/protobuf v1.31.0 // indirect
+)
+
+replace github.com/GoogleCloudPlatform/opentelemetry-operations-go/exporter/metric => ../../../exporter/metric