Case insensitive service provider (#1478)

aws · Dec 23, 2024 · 03cbd6b · 03cbd6b
1 parent 43d475d
commit 03cbd6b
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Showing 5 changed files with 69 additions and 24 deletions.
diff --git a/extension/entitystore/extension_test.go b/extension/entitystore/extension_test.go
@@ -20,6 +20,7 @@ import (
 	"github.com/stretchr/testify/mock"
 	"go.uber.org/zap"
 	"go.uber.org/zap/zapcore"
+	"golang.org/x/exp/maps"
 
 	"github.com/aws/amazon-cloudwatch-agent/internal/ec2metadataprovider"
 	"github.com/aws/amazon-cloudwatch-agent/plugins/processors/awsentity/entityattributes"
@@ -108,15 +109,11 @@ func (m *mockMetadataProvider) InstanceID(ctx context.Context) (string, error) {
 	return "MockInstanceID", nil
 }
 
-func (m *mockMetadataProvider) InstanceTags(ctx context.Context) (string, error) {
+func (m *mockMetadataProvider) InstanceTags(_ context.Context) ([]string, error) {
 	if m.InstanceTagError {
-		return "", errors.New("an error occurred for instance tag retrieval")
+		return nil, errors.New("an error occurred for instance tag retrieval")
 	}
-	var tagsString string
-	for key, val := range m.Tags {
-		tagsString += key + "=" + val + ","
-	}
-	return tagsString, nil
+	return maps.Keys(m.Tags), nil
 }
 
 func (m *mockMetadataProvider) ClientIAMRole(ctx context.Context) (string, error) {

diff --git a/extension/entitystore/serviceprovider.go b/extension/entitystore/serviceprovider.go
@@ -40,8 +40,8 @@ const (
 )
 
 var (
-	//priorityMap is ranking in how we prioritize which IMDS tag determines the service name
-	priorityMap = []string{SERVICE, APPLICATION, APP}
+	//serviceProviderPriorities is ranking in how we prioritize which IMDS tag determines the service name
+	serviceProviderPriorities = []string{SERVICE, APPLICATION, APP}
 )
 
 type ServiceAttribute struct {
@@ -245,26 +245,28 @@ func (s *serviceprovider) scrapeIAMRole() error {
 	return nil
 }
 func (s *serviceprovider) scrapeImdsServiceNameAndASG() error {
-	tags, err := s.metadataProvider.InstanceTags(context.Background())
+	tagKeys, err := s.metadataProvider.InstanceTags(context.Background())
 	if err != nil {
 		s.logger.Debug("Failed to get service name from instance tags. This is likely because instance tag is not enabled for IMDS but will not affect agent functionality.")
 		return err
 	}
-	// This will check whether the tags contains SERVICE, APPLICATION, APP, in that order.
-	for _, value := range priorityMap {
-		if strings.Contains(tags, value) {
-			serviceName, err := s.metadataProvider.InstanceTagValue(context.Background(), value)
+
+	// This will check whether the tags contains SERVICE, APPLICATION, APP, in that order (case insensitive)
+	lowerTagKeys := toLowerKeyMap(tagKeys)
+	for _, potentialServiceProviderKey := range serviceProviderPriorities {
+		if originalCaseKey, exists := lowerTagKeys[potentialServiceProviderKey]; exists {
+			serviceName, err := s.metadataProvider.InstanceTagValue(context.Background(), originalCaseKey)
 			if err != nil {
 				continue
-			} else {
-				s.mutex.Lock()
-				s.imdsServiceName = serviceName
-				s.mutex.Unlock()
 			}
+			s.mutex.Lock()
+			s.imdsServiceName = serviceName
+			s.mutex.Unlock()
 			break
 		}
 	}
-	if strings.Contains(tags, ec2tagger.Ec2InstanceTagKeyASG) {
+	// case sensitive
+	if originalCaseKey := lowerTagKeys[strings.ToLower(ec2tagger.Ec2InstanceTagKeyASG)]; originalCaseKey == ec2tagger.Ec2InstanceTagKeyASG {
 		asg, err := s.metadataProvider.InstanceTagValue(context.Background(), ec2tagger.Ec2InstanceTagKeyASG)
 		if err == nil {
 			s.logger.Debug("AutoScalingGroup retrieved through IMDS")
@@ -277,6 +279,7 @@ func (s *serviceprovider) scrapeImdsServiceNameAndASG() error {
 			s.mutex.Unlock()
 		}
 	}
+
 	if s.GetIMDSServiceName() == "" {
 		s.logger.Debug("Service name not found through IMDS")
 	}
@@ -286,6 +289,14 @@ func (s *serviceprovider) scrapeImdsServiceNameAndASG() error {
 	return nil
 }
 
+func toLowerKeyMap(values []string) map[string]string {
+	set := make(map[string]string, len(values))
+	for _, v := range values {
+		set[strings.ToLower(v)] = v
+	}
+	return set
+}
+
 func newServiceProvider(mode string, region string, ec2Info *EC2Info, metadataProvider ec2metadataprovider.MetadataProvider, providerType ec2ProviderType, ec2Credential *configaws.CredentialConfig, done chan struct{}, logger *zap.Logger) serviceProviderInterface {
 	return &serviceprovider{
 		mode:             mode,

diff --git a/extension/entitystore/serviceprovider_test.go b/extension/entitystore/serviceprovider_test.go
@@ -306,6 +306,16 @@ func Test_serviceprovider_scrapeAndgetImdsServiceNameAndASG(t *testing.T) {
 			metadataProvider:   &mockMetadataProvider{InstanceIdentityDocument: mockedInstanceIdentityDoc, Tags: map[string]string{"service": "test-service"}},
 			wantTagServiceName: "test-service",
 		},
+		{
+			name:               "HappyPath_ServiceExistsCaseInsensitive",
+			metadataProvider:   &mockMetadataProvider{InstanceIdentityDocument: mockedInstanceIdentityDoc, Tags: map[string]string{"ServicE": "test-service"}},
+			wantTagServiceName: "test-service",
+		},
+		{
+			name:               "ServiceExistsRequiresExactMatch",
+			metadataProvider:   &mockMetadataProvider{InstanceIdentityDocument: mockedInstanceIdentityDoc, Tags: map[string]string{"sservicee": "test-service"}},
+			wantTagServiceName: "",
+		},
 		{
 			name:               "HappyPath_ApplicationExists",
 			metadataProvider:   &mockMetadataProvider{InstanceIdentityDocument: mockedInstanceIdentityDoc, Tags: map[string]string{"application": "test-application"}},
@@ -358,6 +368,28 @@ func Test_serviceprovider_scrapeAndgetImdsServiceNameAndASG(t *testing.T) {
 				}},
 			wantASGName: "",
 		},
+		{
+			name: "AutoScalingGroup case sensitive",
+			metadataProvider: &mockMetadataProvider{
+				InstanceIdentityDocument: mockedInstanceIdentityDoc,
+				Tags: map[string]string{
+					"aws:autoscaling:groupname": tagVal3,
+					"env":                       "test-env",
+					"name":                      "test-name",
+				}},
+			wantASGName: "",
+		},
+		{
+			name: "AutoScalingGroup exact match",
+			metadataProvider: &mockMetadataProvider{
+				InstanceIdentityDocument: mockedInstanceIdentityDoc,
+				Tags: map[string]string{
+					"aws:autoscaling:groupnamee": tagVal3,
+					"env":                        "test-env",
+					"name":                       "test-name",
+				}},
+			wantASGName: "",
+		},
 		{
 			name:             "Success IMDS tags call with no ASG",
 			metadataProvider: &mockMetadataProvider{InstanceIdentityDocument: mockedInstanceIdentityDoc, Tags: map[string]string{"name": tagVal3}},

diff --git a/internal/ec2metadataprovider/ec2metadataprovider.go b/internal/ec2metadataprovider/ec2metadataprovider.go
@@ -6,6 +6,7 @@ package ec2metadataprovider
 import (
 	"context"
 	"log"
+	"strings"
 
 	"github.com/aws/aws-sdk-go/aws"
 	"github.com/aws/aws-sdk-go/aws/client"
@@ -20,7 +21,7 @@ type MetadataProvider interface {
 	Get(ctx context.Context) (ec2metadata.EC2InstanceIdentityDocument, error)
 	Hostname(ctx context.Context) (string, error)
 	InstanceID(ctx context.Context) (string, error)
-	InstanceTags(ctx context.Context) (string, error)
+	InstanceTags(ctx context.Context) ([]string, error)
 	ClientIAMRole(ctx context.Context) (string, error)
 	InstanceTagValue(ctx context.Context, tagKey string) (string, error)
 }
@@ -67,10 +68,14 @@ func (c *metadataClient) ClientIAMRole(ctx context.Context) (string, error) {
 	})
 }
 
-func (c *metadataClient) InstanceTags(ctx context.Context) (string, error) {
-	return withMetadataFallbackRetry(ctx, c, func(metadataClient *ec2metadata.EC2Metadata) (string, error) {
+func (c *metadataClient) InstanceTags(ctx context.Context) ([]string, error) {
+	tags, err := withMetadataFallbackRetry(ctx, c, func(metadataClient *ec2metadata.EC2Metadata) (string, error) {
 		return metadataClient.GetMetadataWithContext(ctx, "tags/instance")
 	})
+	if err != nil {
+		return nil, err
+	}
+	return strings.Fields(tags), nil
 }
 
 func (c *metadataClient) InstanceTagValue(ctx context.Context, tagKey string) (string, error) {

diff --git a/plugins/processors/ec2tagger/ec2tagger_test.go b/plugins/processors/ec2tagger/ec2tagger_test.go
@@ -144,8 +144,8 @@ func (m *mockMetadataProvider) InstanceID(ctx context.Context) (string, error) {
 	return "MockInstanceID", nil
 }
 
-func (m *mockMetadataProvider) InstanceTags(ctx context.Context) (string, error) {
-	return "MockInstanceTag", nil
+func (m *mockMetadataProvider) InstanceTags(_ context.Context) ([]string, error) {
+	return []string{"MockInstanceTag"}, nil
 }
 
 func (m *mockMetadataProvider) InstanceTagValue(ctx context.Context, tagKey string) (string, error) {