use istio client-go library instead of knative (#1661)

use istio client-go library instead of knative
bump kubernetes dependency version
change code coverage to codecov

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

@@ -0,0 +1,211 @@
+/*
+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 (
+	"fmt"
+	"github.com/prometheus/client_golang/prometheus"
+	"sync"
+	"time"
+)
+
+// KubeOpts is superset struct for prometheus.Opts. The prometheus Opts structure
+// is purposefully not embedded here because that would change struct initialization
+// in the manner which people are currently accustomed.
+//
+// Name must be set to a non-empty string. DeprecatedVersion is defined only
+// if the metric for which this options applies is, in fact, deprecated.
+type KubeOpts struct {
+	Namespace         string
+	Subsystem         string
+	Name              string
+	Help              string
+	ConstLabels       prometheus.Labels
+	DeprecatedVersion string
+	deprecateOnce     sync.Once
+	annotateOnce      sync.Once
+	StabilityLevel    StabilityLevel
+}
+
+// StabilityLevel represents the API guarantees for a given defined metric.
+type StabilityLevel string
+
+const (
+	// ALPHA metrics have no stability guarantees, as such, labels may
+	// be arbitrarily added/removed and the metric may be deleted at any time.
+	ALPHA StabilityLevel = "ALPHA"
+	// STABLE metrics are guaranteed not be mutated and removal is governed by
+	// the deprecation policy outlined in by the control plane metrics stability KEP.
+	STABLE StabilityLevel = "STABLE"
+)
+
+// CounterOpts is an alias for Opts. See there for doc comments.
+type CounterOpts KubeOpts
+
+// Modify help description on the metric description.
+func (o *CounterOpts) markDeprecated() {
+	o.deprecateOnce.Do(func() {
+		o.Help = fmt.Sprintf("(Deprecated since %v) %v", o.DeprecatedVersion, o.Help)
+	})
+}
+
+// annotateStabilityLevel annotates help description on the metric description with the stability level
+// of the metric
+func (o *CounterOpts) annotateStabilityLevel() {
+	o.annotateOnce.Do(func() {
+		o.Help = fmt.Sprintf("[%v] %v", o.StabilityLevel, o.Help)
+	})
+}
+
+// convenience function to allow easy transformation to the prometheus
+// counterpart. This will do more once we have a proper label abstraction
+func (o *CounterOpts) toPromCounterOpts() prometheus.CounterOpts {
+	return prometheus.CounterOpts{
+		Namespace:   o.Namespace,
+		Subsystem:   o.Subsystem,
+		Name:        o.Name,
+		Help:        o.Help,
+		ConstLabels: o.ConstLabels,
+	}
+}
+
+// GaugeOpts is an alias for Opts. See there for doc comments.
+type GaugeOpts KubeOpts
+
+// Modify help description on the metric description.
+func (o *GaugeOpts) markDeprecated() {
+	o.deprecateOnce.Do(func() {
+		o.Help = fmt.Sprintf("(Deprecated since %v) %v", o.DeprecatedVersion, o.Help)
+	})
+}
+
+// annotateStabilityLevel annotates help description on the metric description with the stability level
+// of the metric
+func (o *GaugeOpts) annotateStabilityLevel() {
+	o.annotateOnce.Do(func() {
+		o.Help = fmt.Sprintf("[%v] %v", o.StabilityLevel, o.Help)
+	})
+}
+
+// convenience function to allow easy transformation to the prometheus
+// counterpart. This will do more once we have a proper label abstraction
+func (o GaugeOpts) toPromGaugeOpts() prometheus.GaugeOpts {
+	return prometheus.GaugeOpts{
+		Namespace:   o.Namespace,
+		Subsystem:   o.Subsystem,
+		Name:        o.Name,
+		Help:        o.Help,
+		ConstLabels: o.ConstLabels,
+	}
+}
+
+// HistogramOpts bundles the options for creating a Histogram metric. It is
+// mandatory to set Name to a non-empty string. All other fields are optional
+// and can safely be left at their zero value, although it is strongly
+// encouraged to set a Help string.
+type HistogramOpts struct {
+	Namespace         string
+	Subsystem         string
+	Name              string
+	Help              string
+	ConstLabels       prometheus.Labels
+	Buckets           []float64
+	DeprecatedVersion string
+	deprecateOnce     sync.Once
+	annotateOnce      sync.Once
+	StabilityLevel    StabilityLevel
+}
+
+// Modify help description on the metric description.
+func (o *HistogramOpts) markDeprecated() {
+	o.deprecateOnce.Do(func() {
+		o.Help = fmt.Sprintf("(Deprecated since %v) %v", o.DeprecatedVersion, o.Help)
+	})
+}
+
+// annotateStabilityLevel annotates help description on the metric description with the stability level
+// of the metric
+func (o *HistogramOpts) annotateStabilityLevel() {
+	o.annotateOnce.Do(func() {
+		o.Help = fmt.Sprintf("[%v] %v", o.StabilityLevel, o.Help)
+	})
+}
+
+// convenience function to allow easy transformation to the prometheus
+// counterpart. This will do more once we have a proper label abstraction
+func (o HistogramOpts) toPromHistogramOpts() prometheus.HistogramOpts {
+	return prometheus.HistogramOpts{
+		Namespace:   o.Namespace,
+		Subsystem:   o.Subsystem,
+		Name:        o.Name,
+		Help:        o.Help,
+		ConstLabels: o.ConstLabels,
+		Buckets:     o.Buckets,
+	}
+}
+
+// SummaryOpts bundles the options for creating a Summary metric. It is
+// mandatory to set Name to a non-empty string. While all other fields are
+// optional and can safely be left at their zero value, it is recommended to set
+// a help string and to explicitly set the Objectives field to the desired value
+// as the default value will change in the upcoming v0.10 of the library.
+type SummaryOpts struct {
+	Namespace         string
+	Subsystem         string
+	Name              string
+	Help              string
+	ConstLabels       prometheus.Labels
+	Objectives        map[float64]float64
+	MaxAge            time.Duration
+	AgeBuckets        uint32
+	BufCap            uint32
+	DeprecatedVersion string
+	deprecateOnce     sync.Once
+	annotateOnce      sync.Once
+	StabilityLevel    StabilityLevel
+}
+
+// Modify help description on the metric description.
+func (o *SummaryOpts) markDeprecated() {
+	o.deprecateOnce.Do(func() {
+		o.Help = fmt.Sprintf("(Deprecated since %v) %v", o.DeprecatedVersion, o.Help)
+	})
+}
+
+// annotateStabilityLevel annotates help description on the metric description with the stability level
+// of the metric
+func (o *SummaryOpts) annotateStabilityLevel() {
+	o.annotateOnce.Do(func() {
+		o.Help = fmt.Sprintf("[%v] %v", o.StabilityLevel, o.Help)
+	})
+}
+
+// convenience function to allow easy transformation to the prometheus
+// counterpart. This will do more once we have a proper label abstraction
+func (o SummaryOpts) toPromSummaryOpts() prometheus.SummaryOpts {
+	return prometheus.SummaryOpts{
+		Namespace:   o.Namespace,
+		Subsystem:   o.Subsystem,
+		Name:        o.Name,
+		Help:        o.Help,
+		ConstLabels: o.ConstLabels,
+		Objectives:  o.Objectives,
+		MaxAge:      o.MaxAge,
+		AgeBuckets:  o.AgeBuckets,
+		BufCap:      o.BufCap,
+	}
+}