datadog receiver: Tags translation

Signed-off-by: Jesus Vazquez <jesus.vazquez@grafana.com>

receiver/datadogreceiver/tags.go

@@ -0,0 +1,142 @@
+// Copyright The OpenTelemetry Authors
+// SPDX-License-Identifier: Apache-2.0
+
+package datadogreceiver // import "github.com/open-telemetry/opentelemetry-collector-contrib/receiver/datadogreceiver"
+
+import (
+	"fmt"
+	"strings"
+	"sync"
+
+	"go.opentelemetry.io/collector/pdata/pcommon"
+	semconv "go.opentelemetry.io/collector/semconv/v1.16.0"
+)
+
+// See:
+// https://docs.datadoghq.com/opentelemetry/schema_semantics/semantic_mapping/
+// https://github.com/DataDog/opentelemetry-mapping-go/blob/main/pkg/otlp/attributes/attributes.go
+var datadogKnownResourceAttributes = map[string]string{
+	"env":     semconv.AttributeDeploymentEnvironment,
+	"service": semconv.AttributeServiceName,
+	"version": semconv.AttributeServiceVersion,
+
+	// Container-related attributes
+	"container_id":   semconv.AttributeContainerID,
+	"container_name": semconv.AttributeContainerName,
+	"image_name":     semconv.AttributeContainerImageName,
+	"image_tag":      semconv.AttributeContainerImageTag,
+	"runtime":        semconv.AttributeContainerRuntime,
+
+	// Cloud-related attributes
+	"cloud_provider": semconv.AttributeCloudProvider,
+	"region":         semconv.AttributeCloudRegion,
+	"zone":           semconv.AttributeCloudAvailabilityZone,
+
+	// ECS-related attributes
+	"task_family":        semconv.AttributeAWSECSTaskFamily,
+	"task_arn":           semconv.AttributeAWSECSTaskARN,
+	"ecs_cluster_name":   semconv.AttributeAWSECSClusterARN,
+	"task_version":       semconv.AttributeAWSECSTaskRevision,
+	"ecs_container_name": semconv.AttributeAWSECSContainerARN,
+
+	// K8-related attributes
+	"kube_container_name": semconv.AttributeK8SContainerName,
+	"kube_cluster_name":   semconv.AttributeK8SClusterName,
+	"kube_deployment":     semconv.AttributeK8SDeploymentName,
+	"kube_replica_set":    semconv.AttributeK8SReplicaSetName,
+	"kube_stateful_set":   semconv.AttributeK8SStatefulSetName,
+	"kube_daemon_set":     semconv.AttributeK8SDaemonSetName,
+	"kube_job":            semconv.AttributeK8SJobName,
+	"kube_cronjob":        semconv.AttributeK8SCronJobName,
+	"kube_namespace":      semconv.AttributeK8SNamespaceName,
+	"pod_name":            semconv.AttributeK8SPodName,
+
+	// Other
+	"process_id":       semconv.AttributeProcessPID,
+	"error.stacktrace": semconv.AttributeExceptionStacktrace,
+	"error.msg":        semconv.AttributeExceptionMessage,
+}
+
+// translateDatadogTagToKeyValuePair translates a Datadog tag to a key value pair
+func translateDatadogTagToKeyValuePair(tag string) (key string, value string) {
+	if tag == "" {
+		return "", ""
+	}
+
+	key, val, ok := strings.Cut(tag, ":")
+	if !ok {
+		// Datadog allows for two tag formats, one of which includes a key such as 'env',
+		// followed by a value. Datadog also supports inputTags without the key, but OTel seems
+		// to only support key:value pairs.
+		// The following is a workaround to map unnamed inputTags to key:value pairs and its subject to future
+		// changes if OTel supports unnamed inputTags in the future or if there is a better way to do this.
+		key = fmt.Sprintf("unnamed_%s", tag)
+		val = tag
+	}
+	return key, val
+}
+
+// translateDataDogKeyToOtel translates a Datadog key to an OTel key
+func translateDataDogKeyToOtel(k string) string {
+	if otelKey, ok := datadogKnownResourceAttributes[strings.ToLower(k)]; ok {
+		return otelKey
+	}
+	return k
+}
+
+type StringPool struct {
+	sync.RWMutex
+	pool map[string]string
+}
+
+func newStringPool() *StringPool {
+	return &StringPool{
+		pool: make(map[string]string),
+	}
+}
+
+func (s *StringPool) Intern(str string) string {
+	s.RLock()
+	interned, ok := s.pool[str]
+	s.RUnlock()
+
+	if ok {
+		return interned
+	}
+
+	s.Lock()
+	// Double check if another goroutine has added the string after releasing the read lock
+	interned, ok = s.pool[str]
+	if !ok {
+		interned = str
+		s.pool[str] = str
+	}
+	s.Unlock()
+
+	return interned
+}
+
+func tagsToAttributes(tags []string, host string, stringPool *StringPool) (pcommon.Map, pcommon.Map, pcommon.Map) {
+	resourceAttrs := pcommon.NewMap()
+	scopeAttrs := pcommon.NewMap()
+	dpAttrs := pcommon.NewMap()
+
+	if host != "" {
+		resourceAttrs.PutStr(semconv.AttributeHostName, host)
+	}
+
+	var key, val string
+	for _, tag := range tags {
+		key, val = translateDatadogTagToKeyValuePair(tag)
+		if attr, ok := datadogKnownResourceAttributes[key]; ok {
+			val = stringPool.Intern(val) // No need to intern the key if we already have it
+			resourceAttrs.PutStr(attr, val)
+		} else {
+			key = stringPool.Intern(translateDataDogKeyToOtel(key))
+			val = stringPool.Intern(val)
+			dpAttrs.PutStr(key, val)
+		}
+	}
+
+	return resourceAttrs, scopeAttrs, dpAttrs
+}

receiver/datadogreceiver/tags_test.go

@@ -0,0 +1,160 @@
+// Copyright The OpenTelemetry Authors
+// SPDX-License-Identifier: Apache-2.0
+
+package datadogreceiver
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"go.opentelemetry.io/collector/pdata/pcommon"
+)
+
+func TestGetMetricAttributes(t *testing.T) {
+	cases := []struct {
+		name                  string
+		tags                  []string
+		host                  string
+		expectedResourceAttrs pcommon.Map
+		expectedScopeAttrs    pcommon.Map
+		expectedDpAttrs       pcommon.Map
+	}{
+		{
+			name:                  "empty",
+			tags:                  []string{},
+			host:                  "",
+			expectedResourceAttrs: pcommon.NewMap(),
+			expectedScopeAttrs:    pcommon.NewMap(),
+			expectedDpAttrs:       pcommon.NewMap(),
+		},
+		{
+			name: "host",
+			tags: []string{},
+			host: "host",
+			expectedResourceAttrs: newMapFromKV(t, map[string]any{
+				"host.name": "host",
+			}),
+			expectedScopeAttrs: pcommon.NewMap(),
+			expectedDpAttrs:    pcommon.NewMap(),
+		},
+		{
+			name: "provides both host and tags where some tag keys have to replaced by otel conventions",
+			tags: []string{"env:prod", "service:my-service", "version:1.0"},
+			host: "host",
+			expectedResourceAttrs: newMapFromKV(t, map[string]any{
+				"host.name":              "host",
+				"deployment.environment": "prod",
+				"service.name":           "my-service",
+				"service.version":        "1.0",
+			}),
+			expectedScopeAttrs: pcommon.NewMap(),
+			expectedDpAttrs:    pcommon.NewMap(),
+		},
+		{
+			name: "provides host, tags and unnamed tags",
+			tags: []string{"env:prod", "foo"},
+			host: "host",
+			expectedResourceAttrs: newMapFromKV(t, map[string]any{
+				"host.name":              "host",
+				"deployment.environment": "prod",
+			}),
+			expectedScopeAttrs: pcommon.NewMap(),
+			expectedDpAttrs: newMapFromKV(t, map[string]any{
+				"unnamed_foo": "foo",
+			}),
+		},
+	}
+
+	for _, c := range cases {
+		t.Run(c.name, func(t *testing.T) {
+			pool := newStringPool()
+			resourceAttrs, scopeAttrs, dpAttrs := tagsToAttributes(c.tags, c.host, pool)
+
+			assert.Equal(t, c.expectedResourceAttrs.Len(), resourceAttrs.Len())
+			c.expectedResourceAttrs.Range(func(k string, _ pcommon.Value) bool {
+				ev, _ := c.expectedResourceAttrs.Get(k)
+				av, ok := resourceAttrs.Get(k)
+				assert.True(t, ok)
+				assert.Equal(t, ev, av)
+				return true
+			})
+
+			assert.Equal(t, c.expectedScopeAttrs.Len(), scopeAttrs.Len())
+			c.expectedScopeAttrs.Range(func(k string, _ pcommon.Value) bool {
+				ev, _ := c.expectedScopeAttrs.Get(k)
+				av, ok := scopeAttrs.Get(k)
+				assert.True(t, ok)
+				assert.Equal(t, ev, av)
+				return true
+			})
+
+			assert.Equal(t, c.expectedDpAttrs.Len(), dpAttrs.Len())
+			c.expectedDpAttrs.Range(func(k string, _ pcommon.Value) bool {
+				ev, _ := c.expectedDpAttrs.Get(k)
+				av, ok := dpAttrs.Get(k)
+				assert.True(t, ok)
+				assert.Equal(t, ev, av)
+				return true
+			})
+		})
+
+	}
+
+}
+
+func newMapFromKV(t *testing.T, kv map[string]any) pcommon.Map {
+	m := pcommon.NewMap()
+	err := m.FromRaw(kv)
+	assert.NoError(t, err)
+	return m
+}
+
+func TestDatadogTagToKeyValuePair(t *testing.T) {
+	cases := []struct {
+		name          string
+		input         string
+		expectedKey   string
+		expectedValue string
+	}{
+		{
+			name:          "empty",
+			input:         "",
+			expectedKey:   "",
+			expectedValue: "",
+		},
+		{
+			name:          "kv tag",
+			input:         "foo:bar",
+			expectedKey:   "foo",
+			expectedValue: "bar",
+		},
+		{
+			name:          "unnamed tag",
+			input:         "foo",
+			expectedKey:   "unnamed_foo",
+			expectedValue: "foo",
+		},
+	}
+
+	for _, c := range cases {
+		t.Run(c.name, func(t *testing.T) {
+			key, value := translateDatadogTagToKeyValuePair(c.input)
+			if key != c.expectedKey {
+				t.Errorf("Expected key %s, got %s", c.expectedKey, key)
+			}
+			if value != c.expectedValue {
+				t.Errorf("Expected value %s, got %s", c.expectedValue, value)
+			}
+		})
+	}
+
+}
+
+func TestTranslateDataDogKeyToOtel(t *testing.T) {
+	// make sure all known keys are translated
+	for k, v := range datadogKnownResourceAttributes {
+		t.Run(k, func(t *testing.T) {
+			assert.Equal(t, v, translateDataDogKeyToOtel(k))
+		})
+	}
+}

receiver/datadogreceiver/traces_translator.go

@@ -155,32 +155,6 @@ func toTraces(payload *pb.TracerPayload, req *http.Request) ptrace.Traces {
 	return results
 }
 
-func translateDataDogKeyToOtel(k string) string {
-	switch strings.ToLower(k) {
-	case "env":
-		return semconv.AttributeDeploymentEnvironment
-	case "version":
-		return semconv.AttributeServiceVersion
-	case "container_id":
-		return semconv.AttributeContainerID
-	case "container_name":
-		return semconv.AttributeContainerName
-	case "image_name":
-		return semconv.AttributeContainerImageName
-	case "image_tag":
-		return semconv.AttributeContainerImageTag
-	case "process_id":
-		return semconv.AttributeProcessPID
-	case "error.stacktrace":
-		return semconv.AttributeExceptionStacktrace
-	case "error.msg":
-		return semconv.AttributeExceptionMessage
-	default:
-		return k
-	}
-
-}
-
 var bufferPool = sync.Pool{
 	New: func() any {
 		return new(bytes.Buffer)