introduce metric naming test (#3789)

* introduce metric naming test

Signed-off-by: zounengren <zounengren@cmss.chinamobile.com>

* Update metrics.go

Signed-off-by: zounengren <zounengren@cmss.chinamobile.com>

1 files changed, 31 insertions, 0 deletions

diff --git a/plugin/dnssec/metrics.go b/plugin/dnssec/metrics.go
new file mode 100644
index 000000000..20da38f36
--- /dev/null
+++ b/plugin/dnssec/metrics.go
@@ -0,0 +1,31 @@
+package dnssec
+
+import (
+	"github.com/coredns/coredns/plugin"
+
+	"github.com/prometheus/client_golang/prometheus"
+)
+
+var (
+	// cacheSize is the number of elements in the dnssec cache.
+	cacheSize = prometheus.NewGaugeVec(prometheus.GaugeOpts{
+		Namespace: plugin.Namespace,
+		Subsystem: "dnssec",
+		Name:      "cache_entries",
+		Help:      "The number of elements in the dnssec cache.",
+	}, []string{"server", "type"})
+	// cacheHits is the count of cache hits.
+	cacheHits = prometheus.NewCounterVec(prometheus.CounterOpts{
+		Namespace: plugin.Namespace,
+		Subsystem: "dnssec",
+		Name:      "cache_hits_total",
+		Help:      "The count of cache hits.",
+	}, []string{"server"})
+	// cacheMisses is the count of cache misses.
+	cacheMisses = prometheus.NewCounterVec(prometheus.CounterOpts{
+		Namespace: plugin.Namespace,
+		Subsystem: "dnssec",
+		Name:      "cache_misses_total",
+		Help:      "The count of cache misses.",
+	}, []string{"server"})
+)