[OASIS-37] Move collector internal/datadog to Agent as modules

comp/otelcol/otlp/components/metricsclient/doc.go

@@ -0,0 +1,7 @@
+// Unless explicitly stated otherwise all files in this repository are licensed
+// under the Apache License Version 2.0.
+// This product includes software developed at Datadog (https://www.datadoghq.com/).
+// Copyright 2024-present Datadog, Inc.
+
+// Package metricsclient provides a statsd.ClientInterface implementation to datadog exporter and datadog connector
+package metricsclient

comp/otelcol/otlp/components/metricsclient/go.mod

@@ -0,0 +1,29 @@
+module github.com/DataDog/datadog-agent/comp/otelcol/otlp/components/metricsclient
+
+go 1.21.0
+
+replace github.com/DataDog/datadog-agent/pkg/trace => ../../../../../pkg/trace
+
+require (
+	github.com/DataDog/datadog-agent/pkg/trace v0.52.1
+	github.com/DataDog/datadog-go/v5 v5.5.0
+	github.com/stretchr/testify v1.9.0
+	go.opentelemetry.io/otel v1.26.0
+	go.opentelemetry.io/otel/metric v1.26.0
+	go.opentelemetry.io/otel/sdk/metric v1.26.0
+)
+
+require (
+	github.com/Microsoft/go-winio v0.6.1 // indirect
+	github.com/davecgh/go-spew v1.1.1 // indirect
+	github.com/go-logr/logr v1.4.1 // indirect
+	github.com/go-logr/stdr v1.2.2 // indirect
+	github.com/pmezard/go-difflib v1.0.0 // indirect
+	go.opentelemetry.io/otel/sdk v1.26.0 // indirect
+	go.opentelemetry.io/otel/trace v1.26.0 // indirect
+	go.uber.org/atomic v1.11.0 // indirect
+	golang.org/x/mod v0.17.0 // indirect
+	golang.org/x/sys v0.19.0 // indirect
+	golang.org/x/tools v0.16.1 // indirect
+	gopkg.in/yaml.v3 v3.0.1 // indirect
+)

comp/otelcol/otlp/components/metricsclient/metrics_client.go

@@ -0,0 +1,181 @@
+// Copyright The OpenTelemetry Authors
+// SPDX-License-Identifier: Apache-2.0
+
+package metricsclient
+
+import (
+	"context"
+	"strings"
+	"sync"
+	"time"
+
+	"github.com/DataDog/datadog-go/v5/statsd"
+	"go.opentelemetry.io/otel/attribute"
+	"go.opentelemetry.io/otel/metric"
+)
+
+const (
+	// ExporterSourceTag is the source tag for Datadog exporter
+	ExporterSourceTag = "datadogexporter"
+	// ConnectorSourceTag is the source tag for Datadog connector
+	ConnectorSourceTag = "datadogconnector"
+)
+
+type metricsClient struct {
+	meter  metric.Meter
+	gauges map[string]float64
+	mutex  sync.Mutex
+	source string
+}
+
+// InitializeMetricClient using a meter provider.
+func InitializeMetricClient(mp metric.MeterProvider, source string) statsd.ClientInterface {
+	return &metricsClient{
+		meter:  mp.Meter("datadog"),
+		gauges: make(map[string]float64),
+		source: source,
+	}
+}
+
+// Gauge implements the Statsd Gauge interface
+func (m *metricsClient) Gauge(name string, value float64, tags []string, _ float64) error {
+	// The last parameter is rate, but we're omitting it because rate does not have effect for gauge points: https://github.com/open-telemetry/opentelemetry-collector-contrib/blob/dedd44436ae064f5a0b43769d24adf897533957b/receiver/statsdreceiver/internal/protocol/metric_translator.go#L153-L156
+	m.mutex.Lock()
+	defer m.mutex.Unlock()
+	if _, ok := m.gauges[name]; ok {
+		m.gauges[name] = value
+		return nil
+	}
+	m.gauges[name] = value
+	_, err := m.meter.Float64ObservableGauge(name, metric.WithFloat64Callback(func(_ context.Context, f metric.Float64Observer) error {
+		attr := m.attributeFromTags(tags)
+		m.mutex.Lock()
+		defer m.mutex.Unlock()
+		if v, ok := m.gauges[name]; ok {
+			f.Observe(v, metric.WithAttributeSet(attr))
+		}
+		return nil
+	}))
+	if err != nil {
+		return err
+	}
+	return nil
+}
+
+// Count implements the Statsd Count interface
+func (m *metricsClient) Count(name string, value int64, tags []string, _ float64) error {
+	counter, err := m.meter.Int64Counter(name)
+	if err != nil {
+		return err
+	}
+	attr := m.attributeFromTags(tags)
+	counter.Add(context.Background(), value, metric.WithAttributeSet(attr))
+	return nil
+}
+
+func (m *metricsClient) attributeFromTags(tags []string) attribute.Set {
+	attr := make([]attribute.KeyValue, 0, len(tags)+1)
+	attr = append(attr, attribute.KeyValue{
+		Key:   "source",
+		Value: attribute.StringValue(m.source),
+	})
+	for _, t := range tags {
+		kv := strings.Split(t, ":")
+		attr = append(attr, attribute.KeyValue{
+			Key:   attribute.Key(kv[0]),
+			Value: attribute.StringValue(kv[1]),
+		})
+	}
+	return attribute.NewSet(attr...)
+}
+
+// Histogram implements the Statsd Histogram interface
+func (m *metricsClient) Histogram(name string, value float64, tags []string, _ float64) error {
+	hist, err := m.meter.Float64Histogram(name)
+	if err != nil {
+		return err
+	}
+	attr := m.attributeFromTags(tags)
+	hist.Record(context.Background(), value, metric.WithAttributeSet(attr))
+	return nil
+}
+
+// Distribution implements the Statsd Distribution interface
+func (m *metricsClient) Distribution(name string, value float64, tags []string, rate float64) error {
+	return m.Histogram(name, value, tags, rate)
+}
+
+// Timing implements the Statsd Timing interface
+func (m *metricsClient) Timing(name string, value time.Duration, tags []string, rate float64) error {
+	return m.TimeInMilliseconds(name, value.Seconds()*1000, tags, rate)
+}
+
+// TimeInMilliseconds implements the Statsd TimeInMilliseconds interface
+func (m *metricsClient) TimeInMilliseconds(name string, value float64, tags []string, rate float64) error {
+	return m.Histogram(name, value, tags, rate)
+}
+
+// Decr implements the Statsd Decr interface
+func (m *metricsClient) Decr(name string, tags []string, rate float64) error {
+	return m.Count(name, -1, tags, rate)
+}
+
+// Incr implements the Statsd Incr interface
+func (m *metricsClient) Incr(name string, tags []string, rate float64) error {
+	return m.Count(name, 1, tags, rate)
+}
+
+// Flush implements the Statsd Flush interface
+func (m *metricsClient) Flush() error {
+	return nil
+}
+
+// Set implements the Statsd Set interface
+func (m *metricsClient) Set(string, string, []string, float64) error {
+	return nil
+}
+
+// Event implements the Statsd Event interface
+func (m *metricsClient) Event(*statsd.Event) error {
+	return nil
+}
+
+// SimpleEvent implements the Statsd SimpleEvent interface
+func (m *metricsClient) SimpleEvent(string, string) error {
+	return nil
+}
+
+// ServiceCheck implements the Statsd ServiceCheck interface
+func (m *metricsClient) ServiceCheck(*statsd.ServiceCheck) error {
+	return nil
+}
+
+// SimpleServiceCheck implements the Statsd SimpleServiceCheck interface
+func (m *metricsClient) SimpleServiceCheck(string, statsd.ServiceCheckStatus) error {
+	return nil
+}
+
+// Close implements the Statsd Close interface
+func (m *metricsClient) Close() error {
+	return nil
+}
+
+// IsClosed implements the Statsd IsClosed interface
+func (m *metricsClient) IsClosed() bool {
+	return false
+}
+
+// GetTelemetry implements the Statsd GetTelemetry interface
+func (m *metricsClient) GetTelemetry() statsd.Telemetry {
+	return statsd.Telemetry{}
+}
+
+// GaugeWithTimestamp implements the Statsd GaugeWithTimestamp interface
+func (m *metricsClient) GaugeWithTimestamp(string, float64, []string, float64, time.Time) error {
+	return nil
+}
+
+// CountWithTimestamp implements the Statsd CountWithTimestamp interface
+func (m *metricsClient) CountWithTimestamp(string, int64, []string, float64, time.Time) error {
+	return nil
+}