[VOL-2235] Mocks and interfaces for rw-core
This update consists of mocks that are used by the rw-core
during unit testing. It also includes interfaces used for unit
tests.
Change-Id: I20ca1455c358113c3aa897acc6355e0ddbc614b7
diff --git a/vendor/github.com/prometheus/client_golang/prometheus/gauge.go b/vendor/github.com/prometheus/client_golang/prometheus/gauge.go
new file mode 100644
index 0000000..71d406b
--- /dev/null
+++ b/vendor/github.com/prometheus/client_golang/prometheus/gauge.go
@@ -0,0 +1,286 @@
+// Copyright 2014 The Prometheus 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 prometheus
+
+import (
+ "math"
+ "sync/atomic"
+ "time"
+
+ dto "github.com/prometheus/client_model/go"
+)
+
+// Gauge is a Metric that represents a single numerical value that can
+// arbitrarily go up and down.
+//
+// A Gauge is typically used for measured values like temperatures or current
+// memory usage, but also "counts" that can go up and down, like the number of
+// running goroutines.
+//
+// To create Gauge instances, use NewGauge.
+type Gauge interface {
+ Metric
+ Collector
+
+ // Set sets the Gauge to an arbitrary value.
+ Set(float64)
+ // Inc increments the Gauge by 1. Use Add to increment it by arbitrary
+ // values.
+ Inc()
+ // Dec decrements the Gauge by 1. Use Sub to decrement it by arbitrary
+ // values.
+ Dec()
+ // Add adds the given value to the Gauge. (The value can be negative,
+ // resulting in a decrease of the Gauge.)
+ Add(float64)
+ // Sub subtracts the given value from the Gauge. (The value can be
+ // negative, resulting in an increase of the Gauge.)
+ Sub(float64)
+
+ // SetToCurrentTime sets the Gauge to the current Unix time in seconds.
+ SetToCurrentTime()
+}
+
+// GaugeOpts is an alias for Opts. See there for doc comments.
+type GaugeOpts Opts
+
+// NewGauge creates a new Gauge based on the provided GaugeOpts.
+//
+// The returned implementation is optimized for a fast Set method. If you have a
+// choice for managing the value of a Gauge via Set vs. Inc/Dec/Add/Sub, pick
+// the former. For example, the Inc method of the returned Gauge is slower than
+// the Inc method of a Counter returned by NewCounter. This matches the typical
+// scenarios for Gauges and Counters, where the former tends to be Set-heavy and
+// the latter Inc-heavy.
+func NewGauge(opts GaugeOpts) Gauge {
+ desc := NewDesc(
+ BuildFQName(opts.Namespace, opts.Subsystem, opts.Name),
+ opts.Help,
+ nil,
+ opts.ConstLabels,
+ )
+ result := &gauge{desc: desc, labelPairs: desc.constLabelPairs}
+ result.init(result) // Init self-collection.
+ return result
+}
+
+type gauge struct {
+ // valBits contains the bits of the represented float64 value. It has
+ // to go first in the struct to guarantee alignment for atomic
+ // operations. http://golang.org/pkg/sync/atomic/#pkg-note-BUG
+ valBits uint64
+
+ selfCollector
+
+ desc *Desc
+ labelPairs []*dto.LabelPair
+}
+
+func (g *gauge) Desc() *Desc {
+ return g.desc
+}
+
+func (g *gauge) Set(val float64) {
+ atomic.StoreUint64(&g.valBits, math.Float64bits(val))
+}
+
+func (g *gauge) SetToCurrentTime() {
+ g.Set(float64(time.Now().UnixNano()) / 1e9)
+}
+
+func (g *gauge) Inc() {
+ g.Add(1)
+}
+
+func (g *gauge) Dec() {
+ g.Add(-1)
+}
+
+func (g *gauge) Add(val float64) {
+ for {
+ oldBits := atomic.LoadUint64(&g.valBits)
+ newBits := math.Float64bits(math.Float64frombits(oldBits) + val)
+ if atomic.CompareAndSwapUint64(&g.valBits, oldBits, newBits) {
+ return
+ }
+ }
+}
+
+func (g *gauge) Sub(val float64) {
+ g.Add(val * -1)
+}
+
+func (g *gauge) Write(out *dto.Metric) error {
+ val := math.Float64frombits(atomic.LoadUint64(&g.valBits))
+ return populateMetric(GaugeValue, val, g.labelPairs, out)
+}
+
+// GaugeVec is a Collector that bundles a set of Gauges that all share the same
+// Desc, but have different values for their variable labels. This is used if
+// you want to count the same thing partitioned by various dimensions
+// (e.g. number of operations queued, partitioned by user and operation
+// type). Create instances with NewGaugeVec.
+type GaugeVec struct {
+ *metricVec
+}
+
+// NewGaugeVec creates a new GaugeVec based on the provided GaugeOpts and
+// partitioned by the given label names.
+func NewGaugeVec(opts GaugeOpts, labelNames []string) *GaugeVec {
+ desc := NewDesc(
+ BuildFQName(opts.Namespace, opts.Subsystem, opts.Name),
+ opts.Help,
+ labelNames,
+ opts.ConstLabels,
+ )
+ return &GaugeVec{
+ metricVec: newMetricVec(desc, func(lvs ...string) Metric {
+ if len(lvs) != len(desc.variableLabels) {
+ panic(makeInconsistentCardinalityError(desc.fqName, desc.variableLabels, lvs))
+ }
+ result := &gauge{desc: desc, labelPairs: makeLabelPairs(desc, lvs)}
+ result.init(result) // Init self-collection.
+ return result
+ }),
+ }
+}
+
+// GetMetricWithLabelValues returns the Gauge for the given slice of label
+// values (same order as the VariableLabels in Desc). If that combination of
+// label values is accessed for the first time, a new Gauge is created.
+//
+// It is possible to call this method without using the returned Gauge to only
+// create the new Gauge but leave it at its starting value 0. See also the
+// SummaryVec example.
+//
+// Keeping the Gauge for later use is possible (and should be considered if
+// performance is critical), but keep in mind that Reset, DeleteLabelValues and
+// Delete can be used to delete the Gauge from the GaugeVec. In that case, the
+// Gauge will still exist, but it will not be exported anymore, even if a
+// Gauge with the same label values is created later. See also the CounterVec
+// example.
+//
+// An error is returned if the number of label values is not the same as the
+// number of VariableLabels in Desc (minus any curried labels).
+//
+// Note that for more than one label value, this method is prone to mistakes
+// caused by an incorrect order of arguments. Consider GetMetricWith(Labels) as
+// an alternative to avoid that type of mistake. For higher label numbers, the
+// latter has a much more readable (albeit more verbose) syntax, but it comes
+// with a performance overhead (for creating and processing the Labels map).
+func (v *GaugeVec) GetMetricWithLabelValues(lvs ...string) (Gauge, error) {
+ metric, err := v.metricVec.getMetricWithLabelValues(lvs...)
+ if metric != nil {
+ return metric.(Gauge), err
+ }
+ return nil, err
+}
+
+// GetMetricWith returns the Gauge for the given Labels map (the label names
+// must match those of the VariableLabels in Desc). If that label map is
+// accessed for the first time, a new Gauge is created. Implications of
+// creating a Gauge without using it and keeping the Gauge for later use are
+// the same as for GetMetricWithLabelValues.
+//
+// An error is returned if the number and names of the Labels are inconsistent
+// with those of the VariableLabels in Desc (minus any curried labels).
+//
+// This method is used for the same purpose as
+// GetMetricWithLabelValues(...string). See there for pros and cons of the two
+// methods.
+func (v *GaugeVec) GetMetricWith(labels Labels) (Gauge, error) {
+ metric, err := v.metricVec.getMetricWith(labels)
+ if metric != nil {
+ return metric.(Gauge), err
+ }
+ return nil, err
+}
+
+// WithLabelValues works as GetMetricWithLabelValues, but panics where
+// GetMetricWithLabelValues would have returned an error. Not returning an
+// error allows shortcuts like
+// myVec.WithLabelValues("404", "GET").Add(42)
+func (v *GaugeVec) WithLabelValues(lvs ...string) Gauge {
+ g, err := v.GetMetricWithLabelValues(lvs...)
+ if err != nil {
+ panic(err)
+ }
+ return g
+}
+
+// With works as GetMetricWith, but panics where GetMetricWithLabels would have
+// returned an error. Not returning an error allows shortcuts like
+// myVec.With(prometheus.Labels{"code": "404", "method": "GET"}).Add(42)
+func (v *GaugeVec) With(labels Labels) Gauge {
+ g, err := v.GetMetricWith(labels)
+ if err != nil {
+ panic(err)
+ }
+ return g
+}
+
+// CurryWith returns a vector curried with the provided labels, i.e. the
+// returned vector has those labels pre-set for all labeled operations performed
+// on it. The cardinality of the curried vector is reduced accordingly. The
+// order of the remaining labels stays the same (just with the curried labels
+// taken out of the sequence – which is relevant for the
+// (GetMetric)WithLabelValues methods). It is possible to curry a curried
+// vector, but only with labels not yet used for currying before.
+//
+// The metrics contained in the GaugeVec are shared between the curried and
+// uncurried vectors. They are just accessed differently. Curried and uncurried
+// vectors behave identically in terms of collection. Only one must be
+// registered with a given registry (usually the uncurried version). The Reset
+// method deletes all metrics, even if called on a curried vector.
+func (v *GaugeVec) CurryWith(labels Labels) (*GaugeVec, error) {
+ vec, err := v.curryWith(labels)
+ if vec != nil {
+ return &GaugeVec{vec}, err
+ }
+ return nil, err
+}
+
+// MustCurryWith works as CurryWith but panics where CurryWith would have
+// returned an error.
+func (v *GaugeVec) MustCurryWith(labels Labels) *GaugeVec {
+ vec, err := v.CurryWith(labels)
+ if err != nil {
+ panic(err)
+ }
+ return vec
+}
+
+// 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
+}
+
+// NewGaugeFunc creates a new GaugeFunc based on the provided GaugeOpts. The
+// value reported is determined by calling the given function from within the
+// Write method. Take into account that metric collection may happen
+// concurrently. If that results in concurrent calls to Write, like in the case
+// where a GaugeFunc is directly registered with Prometheus, the provided
+// function must be concurrency-safe.
+func NewGaugeFunc(opts GaugeOpts, function func() float64) GaugeFunc {
+ return newValueFunc(NewDesc(
+ BuildFQName(opts.Namespace, opts.Subsystem, opts.Name),
+ opts.Help,
+ nil,
+ opts.ConstLabels,
+ ), GaugeValue, function)
+}