Enforcing limits on Application Signals metric dimension value

plugins/processors/awsapplicationsignals/internal/normalizer/attributesnormalizer.go

@@ -16,13 +16,23 @@ import (
 	attr "github.com/aws/amazon-cloudwatch-agent/plugins/processors/awsapplicationsignals/internal/attributes"
 )
 
+const (
+	// Length limits from Application Signals SLOs
+	MaxEnvironmentLength = 259
+	MaxServiceNameLength = 255
+
+	// Length limits from CloudWatch Metrics
+	DefaultMetricAttributeLength = 1024
+)
+
 type attributesNormalizer struct {
 	logger *zap.Logger
 }
 
 var attributesRenamingForMetric = map[string]string{
 	attr.AWSLocalService:             common.MetricAttributeLocalService,
 	attr.AWSLocalOperation:           common.MetricAttributeLocalOperation,
+	attr.AWSLocalEnvironment:         common.MetricAttributeEnvironment,
 	attr.AWSRemoteService:            common.MetricAttributeRemoteService,
 	attr.AWSRemoteOperation:          common.MetricAttributeRemoteOperation,
 	attr.AWSRemoteEnvironment:        common.MetricAttributeRemoteEnvironment,
@@ -45,8 +55,7 @@ var resourceAttributesRenamingForTrace = map[string]string{
 }
 
 var attributesRenamingForTrace = map[string]string{
-	common.MetricAttributeEnvironment: attr.AWSLocalEnvironment,
-	attr.AWSRemoteTarget:              attr.AWSRemoteResourceIdentifier,
+	attr.AWSRemoteTarget: attr.AWSRemoteResourceIdentifier,
 }
 
 var copyMapForMetric = map[string]string{
@@ -75,6 +84,10 @@ func NewAttributesNormalizer(logger *zap.Logger) *attributesNormalizer {
 
 func (n *attributesNormalizer) Process(attributes, resourceAttributes pcommon.Map, isTrace bool) error {
 	n.copyResourceAttributesToAttributes(attributes, resourceAttributes, isTrace)
+	// It's assumed that all attributes are initially inserted as trace attribute, and attributesRenamingForMetric
+	// contains all attributes that will be used for CloudWatch metric dimension. Therefore, we iterate the keys
+	// for enforcing the limits on length.
+	truncateAttributesByLength(attributes)
 	n.renameAttributes(attributes, resourceAttributes, isTrace)
 	n.appendNewAttributes(attributes, resourceAttributes, isTrace)
 	return nil
@@ -160,3 +173,29 @@ func rename(attrs pcommon.Map, renameMap map[string]string) {
 		}
 	}
 }
+
+func truncateAttributesByLength(attributes pcommon.Map) {
+	for attrKey, _ := range attributesRenamingForMetric {
+		switch attrKey {
+		case attr.AWSLocalEnvironment, attr.AWSRemoteEnvironment:
+			if val, ok := attributes.Get(attrKey); ok {
+				attributes.PutStr(attrKey, truncateStringByLength(val.Str(), MaxEnvironmentLength))
+			}
+		case attr.AWSLocalService, attr.AWSRemoteService:
+			if val, ok := attributes.Get(attrKey); ok {
+				attributes.PutStr(attrKey, truncateStringByLength(val.Str(), MaxServiceNameLength))
+			}
+		default:
+			if val, ok := attributes.Get(attrKey); ok {
+				attributes.PutStr(attrKey, truncateStringByLength(val.Str(), DefaultMetricAttributeLength))
+			}
+		}
+	}
+}
+
+func truncateStringByLength(val string, length int) string {
+	if len(val) > length {
+		return val[:length]
+	}
+	return val
+}

plugins/processors/awsapplicationsignals/internal/normalizer/attributesnormalizer_test.go

@@ -10,6 +10,8 @@ import (
 	"go.opentelemetry.io/collector/pdata/pcommon"
 	conventions "go.opentelemetry.io/collector/semconv/v1.6.1"
 	"go.uber.org/zap"
+
+	attr "github.com/aws/amazon-cloudwatch-agent/plugins/processors/awsapplicationsignals/internal/attributes"
 )
 
 func TestRenameAttributes_for_metric(t *testing.T) {
@@ -106,6 +108,32 @@ func TestCopyResourceAttributesToAttributes(t *testing.T) {
 	}
 }
 
+func TestTruncateAttributes(t *testing.T) {
+	attributes := pcommon.NewMap()
+
+	longValue := make([]byte, 300)
+	for i := 0; i < 300; i++ {
+		longValue[i] = 'a'
+	}
+	longStringValue := string(longValue)
+	for key, _ := range attributesRenamingForMetric {
+		attributes.PutStr(key, longStringValue)
+	}
+
+	truncateAttributesByLength(attributes)
+
+	val, _ := attributes.Get(attr.AWSLocalEnvironment)
+	assert.True(t, len(val.Str()) == MaxEnvironmentLength)
+	val, _ = attributes.Get(attr.AWSRemoteEnvironment)
+	assert.True(t, len(val.Str()) == MaxEnvironmentLength)
+	val, _ = attributes.Get(attr.AWSLocalService)
+	assert.True(t, len(val.Str()) == MaxServiceNameLength)
+	val, _ = attributes.Get(attr.AWSRemoteService)
+	assert.True(t, len(val.Str()) == MaxServiceNameLength)
+	val, _ = attributes.Get(attr.AWSRemoteResourceIdentifier)
+	assert.True(t, len(val.Str()) == 300)
+}
+
 func Test_attributesNormalizer_appendNewAttributes(t *testing.T) {
 	logger, _ := zap.NewDevelopment()
 

plugins/processors/awsapplicationsignals/internal/resolver/attributesresolver.go

@@ -29,15 +29,15 @@ const (
 )
 
 var GenericInheritedAttributes = map[string]string{
-	attr.AWSHostedInEnvironment:             common.MetricAttributeEnvironment,
-	semconv1.AttributeDeploymentEnvironment: common.MetricAttributeEnvironment,
+	attr.AWSHostedInEnvironment:             attr.AWSLocalEnvironment,
+	semconv1.AttributeDeploymentEnvironment: attr.AWSLocalEnvironment,
 	attr.ResourceDetectionHostName:          attr.ResourceDetectionHostName,
 }
 
 // DefaultInheritedAttributes is an allow-list that also renames attributes from the resource detection processor
 var DefaultInheritedAttributes = map[string]string{
-	attr.AWSHostedInEnvironment:             common.MetricAttributeEnvironment,
-	semconv1.AttributeDeploymentEnvironment: common.MetricAttributeEnvironment,
+	attr.AWSHostedInEnvironment:             attr.AWSLocalEnvironment,
+	semconv1.AttributeDeploymentEnvironment: attr.AWSLocalEnvironment,
 	attr.ResourceDetectionASG:               common.AttributeEC2AutoScalingGroupName,
 	attr.ResourceDetectionHostId:            common.AttributeEC2InstanceId,
 	attr.ResourceDetectionHostName:          attr.ResourceDetectionHostName,
@@ -113,20 +113,20 @@ func (h *resourceAttributesResolver) Process(attributes, resourceAttributes pcom
 			attributes.PutStr(mappingKey, val.AsString())
 		}
 	}
-	if _, ok := attributes.Get(common.MetricAttributeEnvironment); !ok {
+	if _, ok := attributes.Get(attr.AWSLocalEnvironment); !ok {
 		if h.defaultEnvPrefix == appsignalsconfig.PlatformECS {
 			if clusterName, ok := getECSClusterName(resourceAttributes); ok {
-				attributes.PutStr(common.MetricAttributeEnvironment, GetDefaultEnvironment(h.defaultEnvPrefix, clusterName))
+				attributes.PutStr(attr.AWSLocalEnvironment, GetDefaultEnvironment(h.defaultEnvPrefix, clusterName))
 			}
 		}
 		if h.defaultEnvPrefix == appsignalsconfig.PlatformEC2 {
 			if asgAttr, ok := resourceAttributes.Get(attr.ResourceDetectionASG); ok {
-				attributes.PutStr(common.MetricAttributeEnvironment, GetDefaultEnvironment(h.defaultEnvPrefix, asgAttr.Str()))
+				attributes.PutStr(attr.AWSLocalEnvironment, GetDefaultEnvironment(h.defaultEnvPrefix, asgAttr.Str()))
 			}
 		}
 	}
-	if _, ok := attributes.Get(common.MetricAttributeEnvironment); !ok {
-		attributes.PutStr(common.MetricAttributeEnvironment, GetDefaultEnvironment(h.defaultEnvPrefix, AttributeEnvironmentDefault))
+	if _, ok := attributes.Get(attr.AWSLocalEnvironment); !ok {
+		attributes.PutStr(attr.AWSLocalEnvironment, GetDefaultEnvironment(h.defaultEnvPrefix, AttributeEnvironmentDefault))
 	}
 	attributes.PutStr(common.AttributePlatformType, h.platformType)
 

plugins/processors/awsapplicationsignals/internal/resolver/attributesresolver_test.go

@@ -64,13 +64,13 @@ func TestResourceAttributesResolverWithNoConfiguredName(t *testing.T) {
 
 			resolver.Process(attributes, resourceAttributes)
 
-			attr, ok := attributes.Get(common.AttributePlatformType)
+			attribute, ok := attributes.Get(common.AttributePlatformType)
 			assert.True(t, ok)
-			assert.Equal(t, tt.platformType, attr.Str())
+			assert.Equal(t, tt.platformType, attribute.Str())
 
-			attr, ok = attributes.Get(common.MetricAttributeEnvironment)
+			attribute, ok = attributes.Get(attr.AWSLocalEnvironment)
 			assert.True(t, ok)
-			assert.Equal(t, tt.platformCode+":default", attr.Str())
+			assert.Equal(t, tt.platformCode+":default", attribute.Str())
 		})
 	}
 }
@@ -88,13 +88,13 @@ func TestResourceAttributesResolverWithECSClusterName(t *testing.T) {
 
 	resolver.Process(attributes, resourceAttributes)
 
-	attr, ok := attributes.Get(common.AttributePlatformType)
+	attribute, ok := attributes.Get(common.AttributePlatformType)
 	assert.True(t, ok)
-	assert.Equal(t, "Generic", attr.Str())
+	assert.Equal(t, "Generic", attribute.Str())
 
-	attr, ok = attributes.Get(common.MetricAttributeEnvironment)
+	attribute, ok = attributes.Get(attr.AWSLocalEnvironment)
 	assert.True(t, ok)
-	assert.Equal(t, "ecs:my-cluster", attr.Str())
+	assert.Equal(t, "ecs:my-cluster", attribute.Str())
 }
 
 func TestResourceAttributesResolverWithOnEC2WithASG(t *testing.T) {
@@ -110,7 +110,7 @@ func TestResourceAttributesResolverWithOnEC2WithASG(t *testing.T) {
 	platformAttr, ok := attributes.Get(common.AttributePlatformType)
 	assert.True(t, ok)
 	assert.Equal(t, "AWS::EC2", platformAttr.Str())
-	envAttr, ok := attributes.Get(common.MetricAttributeEnvironment)
+	envAttr, ok := attributes.Get(attr.AWSLocalEnvironment)
 	assert.True(t, ok)
 	assert.Equal(t, "ec2:my-asg", envAttr.Str())
 }
@@ -162,7 +162,7 @@ func TestResourceAttributesResolverWithCustomEnvironment(t *testing.T) {
 			// insert custom env
 			resourceAttributes.PutStr(attr.AWSHostedInEnvironment, "env1")
 			resolver.Process(attributes, resourceAttributes)
-			envAttr, ok := attributes.Get(common.MetricAttributeEnvironment)
+			envAttr, ok := attributes.Get(attr.AWSLocalEnvironment)
 			assert.True(t, ok)
 			assert.Equal(t, "env1", envAttr.Str())
 
@@ -172,7 +172,7 @@ func TestResourceAttributesResolverWithCustomEnvironment(t *testing.T) {
 			resourceAttributes.PutStr(attr.AWSHostedInEnvironment, "error")
 			resourceAttributes.PutStr(semconv.AttributeDeploymentEnvironment, "env2")
 			resolver.Process(attributes, resourceAttributes)
-			envAttr, ok = attributes.Get(common.MetricAttributeEnvironment)
+			envAttr, ok = attributes.Get(attr.AWSLocalEnvironment)
 			assert.True(t, ok)
 			assert.Equal(t, "env2", envAttr.Str())
 
@@ -181,7 +181,7 @@ func TestResourceAttributesResolverWithCustomEnvironment(t *testing.T) {
 
 			resourceAttributes.PutStr(semconv.AttributeDeploymentEnvironment, "env3")
 			resolver.Process(attributes, resourceAttributes)
-			envAttr, ok = attributes.Get(common.MetricAttributeEnvironment)
+			envAttr, ok = attributes.Get(attr.AWSLocalEnvironment)
 			assert.True(t, ok)
 			assert.Equal(t, "env3", envAttr.Str())
 		})