move watchCache metrics to a seperate file

staging/src/k8s.io/apiserver/pkg/storage/cacher/BUILD

@@ -5,6 +5,7 @@ go_library(
     srcs = [
         "cacher.go",
         "caching_object.go",
+        "metrics.go",
         "time_budget.go",
         "util.go",
         "watch_cache.go",

staging/src/k8s.io/apiserver/pkg/storage/cacher/cacher.go

@@ -39,29 +39,11 @@ import (
 	"k8s.io/apiserver/pkg/storage"
 	utilfeature "k8s.io/apiserver/pkg/util/feature"
 	"k8s.io/client-go/tools/cache"
-	"k8s.io/component-base/metrics"
-	"k8s.io/component-base/metrics/legacyregistry"
 	"k8s.io/klog"
 	utiltrace "k8s.io/utils/trace"
 )
 
-/*
- * By default, all the following metrics are defined as falling under
- * ALPHA stability level https://github.com/kubernetes/enhancements/blob/master/keps/sig-instrumentation/20190404-kubernetes-control-plane-metrics-stability.md#stability-classes)
- *
- * Promoting the stability level of the metric is a responsibility of the component owner, since it
- * involves explicitly acknowledging support for the metric across multiple releases, in accordance with
- * the metric stability policy.
- */
 var (
-	initCounter = metrics.NewCounterVec(
-		&metrics.CounterOpts{
-			Name:           "apiserver_init_events_total",
-			Help:           "Counter of init events processed in watchcache broken by resource type",
-			StabilityLevel: metrics.ALPHA,
-		},
-		[]string{"resource"},
-	)
 	emptyFunc = func() {}
 )
 
@@ -71,10 +53,6 @@ const (
 	storageWatchListPageSize = int64(10000)
 )
 
-func init() {
-	legacyregistry.MustRegister(initCounter)
-}
-
 // Config contains the configuration for a given Cache.
 type Config struct {
 	// Maximum size of the history cached in memory.

staging/src/k8s.io/apiserver/pkg/storage/cacher/metrics.go

@@ -0,0 +1,45 @@
+/*
+Copyright 2019 The Kubernetes Authors.
+
+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 cacher
+
+import (
+	"k8s.io/component-base/metrics"
+	"k8s.io/component-base/metrics/legacyregistry"
+)
+
+/*
+ * By default, all the following metrics are defined as falling under
+ * ALPHA stability level https://github.com/kubernetes/enhancements/blob/master/keps/sig-instrumentation/20190404-kubernetes-control-plane-metrics-stability.md#stability-classes)
+ *
+ * Promoting the stability level of the metric is a responsibility of the component owner, since it
+ * involves explicitly acknowledging support for the metric across multiple releases, in accordance with
+ * the metric stability policy.
+ */
+var (
+	initCounter = metrics.NewCounterVec(
+		&metrics.CounterOpts{
+			Name:           "apiserver_init_events_total",
+			Help:           "Counter of init events processed in watchcache broken by resource type",
+			StabilityLevel: metrics.ALPHA,
+		},
+		[]string{"resource"},
+	)
+)
+
+func init() {
+	legacyregistry.MustRegister(initCounter)
+}