ROB-2312: Add missing metrics file

pkg/metrics/metrics.go

@@ -0,0 +1,38 @@
+/*
+Copyright 2024
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package metrics
+
+import (
+	"github.com/prometheus/client_golang/prometheus"
+	"github.com/prometheus/client_golang/prometheus/promauto"
+)
+
+var (
+	// EventsSentTotal tracks events sent to handlers after filtering
+	EventsSentTotal *prometheus.CounterVec
+)
+
+func init() {
+	// Initialize the sent events metric
+	EventsSentTotal = promauto.NewCounterVec(
+		prometheus.CounterOpts{
+			Name: "kubewatch_events_sent_total",
+			Help: "The total number of Kubernetes events sent to handlers after filtering, labeled by resource and event type",
+		},
+		[]string{"resourceType", "eventType"},
+	)
+}