initial commit

collector/stats_topic.go

@@ -0,0 +1,66 @@
+package collector
+
+import (
+	"strconv"
+
+	"github.com/prometheus/client_golang/prometheus"
+)
+
+// see https://github.com/nsqio/nsq/blob/master/nsqd/stats.go
+type topic struct {
+	Name         string     `json:"topic_name"`
+	Channels     []*channel `json:"channels"`
+	Depth        int64      `json:"depth"`
+	BackendDepth int64      `json:"backend_depth"`
+	MessageCount uint64     `json:"message_count"`
+	Paused       bool       `json:"paused"`
+}
+
+type topicCollector []struct {
+	val func(*topic) float64
+	vec *prometheus.GaugeVec
+}
+
+func newTopicCollector(namespace string) topicCollector {
+	labels := []string{"type", "topic", "paused"}
+
+	return topicCollector{
+		{
+			val: func(t *topic) float64 { return float64(t.Depth) },
+			vec: prometheus.NewGaugeVec(prometheus.GaugeOpts{
+				Namespace: namespace,
+				Name:      "depth",
+				Help:      "Queue depth",
+			}, labels),
+		},
+		{
+			val: func(t *topic) float64 { return float64(t.BackendDepth) },
+			vec: prometheus.NewGaugeVec(prometheus.GaugeOpts{
+				Namespace: namespace,
+				Name:      "backend_depth",
+				Help:      "Queue backend depth",
+			}, labels),
+		},
+		{
+			val: func(t *topic) float64 { return float64(t.MessageCount) },
+			vec: prometheus.NewGaugeVec(prometheus.GaugeOpts{
+				Namespace: namespace,
+				Name:      "message_count",
+				Help:      "Queue message count",
+			}, labels),
+		},
+	}
+}
+
+func (c topicCollector) update(t *topic, out chan<- prometheus.Metric) {
+	labels := prometheus.Labels{
+		"type":   "topic",
+		"topic":  t.Name,
+		"paused": strconv.FormatBool(t.Paused),
+	}
+
+	for _, g := range c {
+		g.vec.With(labels).Set(g.val(t))
+		g.vec.Collect(out)
+	}
+}