Update to kube v1.17

Signed-off-by: Humble Chirammal <hchiramm@redhat.com>

vendor/k8s.io/component-base/metrics/wrappers.go

@@ -0,0 +1,95 @@
+/*
+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 metrics
+
+import (
+	"github.com/prometheus/client_golang/prometheus"
+	dto "github.com/prometheus/client_model/go"
+)
+
+// This file contains a series of interfaces which we explicitly define for
+// integrating with prometheus. We redefine the interfaces explicitly here
+// so that we can prevent breakage if methods are ever added to prometheus
+// variants of them.
+
+// Collector defines a subset of prometheus.Collector interface methods
+type Collector interface {
+	Describe(chan<- *prometheus.Desc)
+	Collect(chan<- prometheus.Metric)
+}
+
+// Metric defines a subset of prometheus.Metric interface methods
+type Metric interface {
+	Desc() *prometheus.Desc
+	Write(*dto.Metric) error
+}
+
+// CounterMetric is a Metric that represents a single numerical value that only ever
+// goes up. That implies that it cannot be used to count items whose number can
+// also go down, e.g. the number of currently running goroutines. Those
+// "counters" are represented by Gauges.
+
+// CounterMetric is an interface which defines a subset of the interface provided by prometheus.Counter
+type CounterMetric interface {
+	Inc()
+	Add(float64)
+}
+
+// CounterVecMetric is an interface which prometheus.CounterVec satisfies.
+type CounterVecMetric interface {
+	WithLabelValues(...string) CounterMetric
+	With(prometheus.Labels) CounterMetric
+}
+
+// GaugeMetric is an interface which defines a subset of the interface provided by prometheus.Gauge
+type GaugeMetric interface {
+	Set(float64)
+	Inc()
+	Dec()
+	Add(float64)
+	Write(out *dto.Metric) error
+	SetToCurrentTime()
+}
+
+// ObserverMetric captures individual observations.
+type ObserverMetric interface {
+	Observe(float64)
+}
+
+// PromRegistry is an interface which implements a subset of prometheus.Registerer and
+// prometheus.Gatherer interfaces
+type PromRegistry interface {
+	Register(prometheus.Collector) error
+	MustRegister(...prometheus.Collector)
+	Unregister(prometheus.Collector) bool
+	Gather() ([]*dto.MetricFamily, error)
+}
+
+// Gatherer is the interface for the part of a registry in charge of gathering
+// the collected metrics into a number of MetricFamilies.
+type Gatherer interface {
+	prometheus.Gatherer
+}
+
+// GaugeFunc is a Gauge whose value is determined at collect time by calling a
+// provided function.
+//
+// To create GaugeFunc instances, use NewGaugeFunc.
+type GaugeFunc interface {
+	Metric
+	Collector
+}