Implement metrics and cli

pkg/metrics/metrics.go

@@ -0,0 +1,17 @@
+package metrics
+
+import (
+	"github.com/prometheus/client_golang/prometheus"
+	"github.com/prometheus/client_golang/prometheus/promauto"
+)
+
+var (
+	NumErrors = promauto.NewGauge(
+		prometheus.GaugeOpts{
+			Namespace: "infra",
+			Subsystem: "pod_cleaner",
+			Name:      "orphans_pod_error_count",
+			Help:      "Number of orphan pods that failed to be cleaned",
+		},
+	)
+)