DogStatsD v1.2 Container ID support with sampling support

pkg/line/line.go

@@ -269,7 +269,7 @@ samples:
 	for _, sample := range samples {
 		samplesReceived.Inc()
 		components := strings.Split(sample, "|")
-		if len(components) < 2 || len(components) > 4 {
+		if len(components) < 2 || len(components) > 5 {
 			sampleErrors.WithLabelValues("malformed_component").Inc()
 			logger.Debug("bad component", "line", line)
 			continue
@@ -320,10 +320,19 @@ samples:
 					}
 				case '#':
 					p.ParseDogStatsDTags(component[1:], labels, tagErrors, logger)
+				case 'c':
+					// Handle DogStatsD v1.2 container ID suffix (e.g., |c:<container_id>)
+					if strings.HasPrefix(component, "c:") && len(component) > 2 {
+						labels["container_id"] = component[2:]
+					} else {
+						logger.Debug("Malformed container ID section", "component", component, "line", line)
+						sampleErrors.WithLabelValues("malformed_container_id").Inc()
+						continue samples
+					}
 				default:
-					logger.Debug("Invalid sampling factor or tag section", "component", components[2], "line", line)
+					logger.Debug("Invalid sampling factor, tag section, or container ID section", "component", components[2], "line", line)
 					sampleErrors.WithLabelValues("invalid_sample_factor").Inc()
-					continue
+					continue samples
 				}
 			}
 		}

pkg/line/line_test.go

@@ -829,6 +829,103 @@ func TestLineToEvents(t *testing.T) {
 		"invalid event split over lines part 2": {
 			in: "|h|#consumer:Kafka::SharedConfigurationConsumer,topic:shared_configuration_update,partition:1,consumer_group:tc_rc_us",
 		},
+		"dogstatsd container ID extension": {
+			in: "foo:100|c|#tag1:value|c:container123",
+			out: event.Events{
+				&event.CounterEvent{
+					CMetricName: "foo",
+					CValue:      100,
+					CLabels:     map[string]string{"tag1": "value", "container_id": "container123"},
+				},
+			},
+		},
+		"dogstatsd container ID with tags": {
+			in: "foo:100|c|#tag1:bar,tag2:baz|c:container456",
+			out: event.Events{
+				&event.CounterEvent{
+					CMetricName: "foo",
+					CValue:      100,
+					CLabels:     map[string]string{"tag1": "bar", "tag2": "baz", "container_id": "container456"},
+				},
+			},
+		},
+		"dogstatsd container ID with gauge": {
+			in: "foo:50|g|#tag1:value|c:gauge_container",
+			out: event.Events{
+				&event.GaugeEvent{
+					GMetricName: "foo",
+					GValue:      50,
+					GLabels:     map[string]string{"tag1": "value", "container_id": "gauge_container"},
+				},
+			},
+		},
+		"dogstatsd container ID with timer": {
+			in: "foo:1000|ms|#tag1:value|c:timer_container",
+			out: event.Events{
+				&event.ObserverEvent{
+					OMetricName: "foo",
+					OValue:      1,
+					OLabels:     map[string]string{"tag1": "value", "container_id": "timer_container"},
+				},
+			},
+		},
+		"dogstatsd container ID with histogram": {
+			in: "foo:500|h|#tag1:value|c:hist_container",
+			out: event.Events{
+				&event.ObserverEvent{
+					OMetricName: "foo",
+					OValue:      500,
+					OLabels:     map[string]string{"tag1": "value", "container_id": "hist_container"},
+				},
+			},
+		},
+		"dogstatsd container ID malformed - no colon": {
+			in:  "foo:100|c|#tag1:value|c",
+			out: event.Events{},
+		},
+		"dogstatsd container ID malformed - no value after colon": {
+			in:  "foo:100|c|#tag1:value|c:",
+			out: event.Events{},
+		},
+		"dogstatsd container ID with complex value": {
+			in: "foo:100|c|#tag1:value|c:sha256:abcd1234efgh5678",
+			out: event.Events{
+				&event.CounterEvent{
+					CMetricName: "foo",
+					CValue:      100,
+					CLabels:     map[string]string{"tag1": "value", "container_id": "sha256:abcd1234efgh5678"},
+				},
+			},
+		},
+		"dogstatsd container ID with sampling": {
+			in: "foo:100|c|@0.1|#service:abc,client:go|c:3a88c225dbeb98f20bbb40cbd39ef90b094ce74291ae66fbd98b7f06f2a15b86",
+			out: event.Events{
+				&event.CounterEvent{
+					CMetricName: "foo",
+					CValue:      1000,
+					CLabels:     map[string]string{"service": "abc", "client": "go", "container_id": "3a88c225dbeb98f20bbb40cbd39ef90b094ce74291ae66fbd98b7f06f2a15b86"},
+				},
+			},
+		},
+		"dogstatsd container ID with sampling and histogram": {
+			in: "foo:200|h|@0.5|#env:prod|c:container_hist",
+			out: event.Events{
+				&event.ObserverEvent{
+					OMetricName: "foo",
+					OValue:      200,
+					OLabels:     map[string]string{"env": "prod", "container_id": "container_hist"},
+				},
+				&event.ObserverEvent{
+					OMetricName: "foo",
+					OValue:      200,
+					OLabels:     map[string]string{"env": "prod", "container_id": "container_hist"},
+				},
+			},
+		},
+		"malformed line with too many components": {
+			in:  "foo:100|c|@0.1|#tag1:value|c:container|extra:component",
+			out: event.Events{},
+		},
 	}
 
 	parser := NewParser()