Merge pull request #105 from amuraru/issue-103

Extract consumer group member_count as a separate metric
redpanda-data · Oct 12, 2021 · 1dd0306 · 1dd0306
2 parents 3f84442 + 00eb355
commit 1dd0306
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Showing 3 changed files with 22 additions and 3 deletions.
diff --git a/docs/metrics.md b/docs/metrics.md
@@ -69,7 +69,11 @@ kminion_kafka_topic_high_water_mark_sum{topic_name="__consumer_offsets"} 1.51202
 ```
 # HELP kminion_kafka_consumer_group_info Consumer Group info metrics. It will report 1 if the group is in the stable state, otherwise 0.
 # TYPE kminion_kafka_consumer_group_info gauge
-kminion_kafka_consumer_group_info{coordinator_id="0",group_id="bigquery-sink",member_count="2",protocol="range",protocol_type="consumer",state="Stable"} 1
+kminion_kafka_consumer_group_info{coordinator_id="0",group_id="bigquery-sink",protocol="range",protocol_type="consumer",state="Stable"} 1
+
+# HELP kminion_kafka_consumer_group_members Consumer Group member count metrics. It will report the number of members in the consumer group
+# TYPE kminion_kafka_consumer_group_members gauge
+kminion_kafka_consumer_group_members{group_id="bigquery-sink"} 2
 
 # HELP kminion_kafka_consumer_group_empty_members Consumer Group Empty Members. It will report the number of members in the consumer group with no partition assigned
 # TYPE kminion_kafka_consumer_group_empty_members gauge

diff --git a/prometheus/collect_consumer_groups.go b/prometheus/collect_consumer_groups.go
@@ -45,13 +45,20 @@ func (e *Exporter) collectConsumerGroups(ctx context.Context, ch chan<- promethe
 				prometheus.GaugeValue,
 				float64(state),
 				group.Group,
-				strconv.Itoa(len(group.Members)),
 				group.Protocol,
 				group.ProtocolType,
 				group.State,
 				strconv.FormatInt(int64(coordinator), 10),
 			)
 
+			// total number of members in consumer groups
+			ch <- prometheus.MustNewConstMetric(
+				e.consumerGroupMembers,
+				prometheus.GaugeValue,
+				float64(len(group.Members)),
+				group.Group,
+			)
+
 			// iterate all members and build two maps:
 			// - {topic -> number-of-consumers}
 			// - {topic -> number-of-partitions-assigned}

diff --git a/prometheus/exporter.go b/prometheus/exporter.go
@@ -40,6 +40,7 @@ type Exporter struct {
 
 	// Consumer Groups
 	consumerGroupInfo                    *prometheus.Desc
+	consumerGroupMembers                 *prometheus.Desc
 	consumerGroupMembersEmpty            *prometheus.Desc
 	consumerGroupTopicMembers            *prometheus.Desc
 	consumerGroupAssignedTopicPartitions *prometheus.Desc
@@ -147,7 +148,14 @@ func (e *Exporter) InitializeMetrics() {
 	e.consumerGroupInfo = prometheus.NewDesc(
 		prometheus.BuildFQName(e.cfg.Namespace, "kafka", "consumer_group_info"),
 		"Consumer Group info metrics. It will report 1 if the group is in the stable state, otherwise 0.",
-		[]string{"group_id", "member_count", "protocol", "protocol_type", "state", "coordinator_id"},
+		[]string{"group_id", "protocol", "protocol_type", "state", "coordinator_id"},
+		nil,
+	)
+	// Group Members
+	e.consumerGroupMembers = prometheus.NewDesc(
+		prometheus.BuildFQName(e.cfg.Namespace, "kafka", "consumer_group_members"),
+		"Consumer Group member count metrics. It will report the number of members in the consumer group",
+		[]string{"group_id"},
 		nil,
 	)
 	// Group Empty Memmbers