fix(byoo-otel-collector): preserve workload metric drop labels

docs/ngc-managed/cluster-management/configuration.md

@@ -788,10 +788,13 @@ BYOO metric subset example:
              - 'metric.name != "BpsInstrument"'
        byooWorkloadMetrics:
          dropLabels:
-           - metric_subset_enabled
            - custom_label
 ```
 
+When `byooMetricSubset.enabled` is true, `dropLabels` extends the default
+`metric_subset_enabled` label. The configured labels are removed from both the
+primary metrics pipeline and the metric subset endpoint on port `19091`.
+
 **Apply via Helm:**
 
 ```bash

docs/user/cluster-management/configuration.md

@@ -918,10 +918,13 @@ agentConfig:
             - 'metric.name != "BpsInstrument"'
       byooWorkloadMetrics:
         dropLabels:
-          - metric_subset_enabled
           - custom_label
 ```
 
+When `byooMetricSubset.enabled` is true, `dropLabels` extends the default
+`metric_subset_enabled` label. The configured labels are removed from both the
+primary metrics pipeline and the metric subset endpoint on port `19091`.
+
 Apply via Helm:
 
 ```bash

src/compute-plane-services/byoo-otel-collector/README.md

@@ -141,7 +141,7 @@ Chunking is disabled by default. Configure it with:
 - `BYOO_OTEL_COLLECTOR_CONFIG_B64`: optional base64-encoded JSON for advanced collector rendering overrides, such as exporterhelper timeout, retry, sending queue, sending queue batch, memory limiter, batch, log batch, and separate log and trace sampler settings. Both samplers support sampling percentage, mode, hash seed, and fail closed. The log sampler also supports attribute source, source attribute, and sampling priority.
 - `BYOO_METRIC_SUBSET_ENABLED`: enables an additional OTLP-only metrics pipeline that exposes filtered user metrics through a Prometheus exporter on port `19091`. Disabled by default.
 - `BYOO_METRIC_SUBSET_FILTER_CONFIG`: optional YAML filter processor config for the metric subset pipeline. If unset, the default drops every metric except `BpsInstrument`, `FpsInstrument`, `RtdInstrument`, and `StageOpenDuration`, and drops datapoints/resources explicitly labeled `metric_subset_enabled=false`.
-- `BYOO_WORKLOAD_METRICS_DROP_LABELS`: comma-separated resource attribute names removed from the generated workload `metrics` pipeline. If unset, defaults to `metric_subset_enabled` only when the metric subset pipeline is enabled.
+- `BYOO_WORKLOAD_METRICS_DROP_LABELS`: comma-separated resource attribute names removed from the generated workload metrics pipelines. When the metric subset pipeline is enabled, configured labels extend the default `metric_subset_enabled` label. Labels are removed from both the primary and metric subset pipelines.
 
 When chunking is enabled, each emitted chunk preserves the original log metadata and adds these attributes so chunks can be grouped in the backend:
 

src/compute-plane-services/byoo-otel-collector/examples/otelconfigs/k8s/config_function_container_metric_subset.yaml

@@ -285,6 +285,7 @@ service:
         - memory_limiter
         - filter/metric_subset
         - resource
+        - resource/workload_metrics_drop_labels
         - metrics_transform
         - batch/metric_subset
   extensions:

src/compute-plane-services/byoo-otel-collector/internal/otelconfig/otelconfig_test.go

@@ -212,7 +212,7 @@ func TestGetTemplateConfig(t *testing.T) {
 				"NVCF_ZONE_NAME":                    "zone-1",
 				"BYOO_METRIC_SUBSET_ENABLED":        "true",
 				"BYOO_METRIC_SUBSET_FILTER_CONFIG":  "error_mode: ignore\nmetric_conditions:\n  - 'metric.name == \"drop\"'\n",
-				"BYOO_WORKLOAD_METRICS_DROP_LABELS": "metric_subset_enabled, custom_label, metric_subset_enabled",
+				"BYOO_WORKLOAD_METRICS_DROP_LABELS": "custom_label",
 			},
 			expectErr: false,
 			expect: func(t *testing.T, cfg TemplateConfig) {

src/compute-plane-services/byoo-otel-collector/internal/otelconfig/render.go

@@ -248,6 +248,12 @@ func resolvedWorkloadMetricsDropLabels(configured string, metricSubsetEnabled bo
 
 	seen := map[string]struct{}{}
 	labels := []string{}
+	if metricSubsetEnabled {
+		for _, label := range defaultWorkloadMetricsDropLabels {
+			seen[label] = struct{}{}
+			labels = append(labels, label)
+		}
+	}
 	for _, label := range strings.Split(configured, ",") {
 		label = strings.TrimSpace(label)
 		if label == "" {
@@ -578,7 +584,7 @@ func cloneConfigValue(value interface{}) interface{} {
 	}
 }
 
-func addMetricSubsetPipeline(otelConfig *OpenTelemetryConfig, config MetricSubsetConfig) {
+func addMetricSubsetPipeline(otelConfig *OpenTelemetryConfig, config MetricSubsetConfig, workloadMetricsDropLabelsProcessor string) {
 	addMetricSubsetExporter(otelConfig)
 
 	filterConfig := config.FilterConfig
@@ -604,9 +610,14 @@ func addMetricSubsetPipeline(otelConfig *OpenTelemetryConfig, config MetricSubse
 		"memory_limiter",
 		metricSubsetFilterProcessorID,
 		"resource",
+	}
+	if workloadMetricsDropLabelsProcessor != "" {
+		metricSubsetPipeline.Processors = append(metricSubsetPipeline.Processors, workloadMetricsDropLabelsProcessor)
+	}
+	metricSubsetPipeline.Processors = append(metricSubsetPipeline.Processors,
 		"metrics_transform",
 		metricSubsetBatchProcessorID,
-	}
+	)
 	otelConfig.Service.Pipelines["metrics/metric_subset"] = metricSubsetPipeline
 }
 
@@ -888,14 +899,15 @@ func generateExportersAndService(config TelemetryConfig, otelConfig *OpenTelemet
 		metricPipeline.Receivers = []string{"otlp", "prometheus"}
 		metricPipeline.Exporters = []string{exporterId}
 		metricPipeline.Processors = []string{"memory_limiter", "filter/metrics", "resource"}
-		if processorID := addWorkloadMetricsDropLabelsProcessor(otelConfig, tmplConfig.WorkloadMetrics.DropLabels); processorID != "" {
-			metricPipeline.Processors = append(metricPipeline.Processors, processorID)
+		workloadMetricsDropLabelsProcessor := addWorkloadMetricsDropLabelsProcessor(otelConfig, tmplConfig.WorkloadMetrics.DropLabels)
+		if workloadMetricsDropLabelsProcessor != "" {
+			metricPipeline.Processors = append(metricPipeline.Processors, workloadMetricsDropLabelsProcessor)
 		}
 		metricPipeline.Processors = append(metricPipeline.Processors, "metrics_transform", "batch")
 		otelConfig.Service.Pipelines["metrics"] = metricPipeline
 
 		if tmplConfig.MetricSubset.Enabled {
-			addMetricSubsetPipeline(otelConfig, tmplConfig.MetricSubset)
+			addMetricSubsetPipeline(otelConfig, tmplConfig.MetricSubset, workloadMetricsDropLabelsProcessor)
 		}
 	}
 

src/compute-plane-services/byoo-otel-collector/internal/otelconfig/render_test.go

@@ -159,6 +159,7 @@ func TestRenderOtelConfigWithMetricSubsetPipeline(t *testing.T) {
 		"memory_limiter",
 		metricSubsetFilterProcessorID,
 		"resource",
+		workloadMetricsDropLabelsProcessorID,
 		"metrics_transform",
 		metricSubsetBatchProcessorID,
 	}, otelConfig.Service.Pipelines["metrics/metric_subset"].Processors)
@@ -856,7 +857,7 @@ func TestGenerateExportersAndServiceAddsMetricSubsetPipeline(t *testing.T) {
 			FilterConfig: filterConfig,
 		},
 		WorkloadMetrics: WorkloadMetricsConfig{
-			DropLabels: []string{"metric_subset_enabled"},
+			DropLabels: []string{"metric_subset_enabled", "custom_label"},
 		},
 	})
 
@@ -888,6 +889,10 @@ func TestGenerateExportersAndServiceAddsMetricSubsetPipeline(t *testing.T) {
 				"key":    "metric_subset_enabled",
 				"action": "delete",
 			},
+			{
+				"key":    "custom_label",
+				"action": "delete",
+			},
 		},
 	}, otelConfig.Processors[workloadMetricsDropLabelsProcessorID])
 
@@ -898,6 +903,7 @@ func TestGenerateExportersAndServiceAddsMetricSubsetPipeline(t *testing.T) {
 		"memory_limiter",
 		metricSubsetFilterProcessorID,
 		"resource",
+		workloadMetricsDropLabelsProcessorID,
 		"metrics_transform",
 		metricSubsetBatchProcessorID,
 	}, metricSubsetPipeline.Processors)