chore: AWS Integration: include CWAgent metrics namespace for ec2 (#7165)

* chore: include CWAgent namespace for ec2 metrics

* chore: update aws integration service metrics connection status queried labels

* chore: fix breaking test

pkg/query-service/app/cloudintegrations/serviceDefinitions/aws/ec2/integration.json

@@ -497,6 +497,9 @@
       "cloudwatch_metric_stream_filters": [
         {
           "Namespace": "AWS/EC2"
+        },
+        {
+          "Namespace": "CWAgent"
         }
       ]
     }

pkg/query-service/app/http_handler.go

@@ -4242,19 +4242,21 @@ func (aH *APIHandler) calculateAWSIntegrationSvcMetricsConnectionStatus(
 		return nil, nil
 	}
 
-	metricsNamespace := strategy.CloudwatchMetricsStreamFilters[0].Namespace
-	metricsNamespaceParts := strings.Split(metricsNamespace, "/")
-	if len(metricsNamespaceParts) < 2 {
-		return nil, model.InternalError(fmt.Errorf(
-			"unexpected metric namespace: %s", metricsNamespace,
-		))
-	}
-
 	expectedLabelValues := map[string]string{
 		"cloud_provider":   "aws",
 		"cloud_account_id": cloudAccountId,
-		"service_namespace": metricsNamespaceParts[0],
+	}
-		"service_name":      metricsNamespaceParts[1],
+
+	metricsNamespace := strategy.CloudwatchMetricsStreamFilters[0].Namespace
+	metricsNamespaceParts := strings.Split(metricsNamespace, "/")
+
+	if len(metricsNamespaceParts) >= 2 {
+		expectedLabelValues["service_namespace"] = metricsNamespaceParts[0]
+		expectedLabelValues["service_name"] = metricsNamespaceParts[1]
+	} else {
+		// metrics for single word namespaces like "CWAgent" do not
+		// have the service_namespace label populated
+		expectedLabelValues["service_name"] = metricsNamespaceParts[0]
 	}
 
 	metricNamesCollectedBySvc := []string{}

pkg/query-service/tests/integration/signoz_cloud_integrations_test.go

@@ -281,7 +281,7 @@ func TestConfigReturnedWhenAgentChecksIn(t *testing.T) {
 	for _, f := range telemetryCollectionStrategy.AWSMetrics.CloudwatchMetricsStreamFilters {
 		metricStreamNamespaces = append(metricStreamNamespaces, f.Namespace)
 	}
-	require.Equal([]string{"AWS/EC2", "AWS/RDS"}, metricStreamNamespaces)
+	require.Equal([]string{"AWS/EC2", "CWAgent", "AWS/RDS"}, metricStreamNamespaces)
 
 	require.NotNil(telemetryCollectionStrategy.AWSLogs)
 	logGroupPrefixes := []string{}