[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/value.go b/vendor/github.com/prometheus/client_golang/prometheus/value.go
new file mode 100644
index 0000000..eb248f1
--- /dev/null
+++ b/vendor/github.com/prometheus/client_golang/prometheus/value.go
@@ -0,0 +1,162 @@
+// 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 (
+ "fmt"
+ "sort"
+
+ "github.com/golang/protobuf/proto"
+
+ dto "github.com/prometheus/client_model/go"
+)
+
+// ValueType is an enumeration of metric types that represent a simple value.
+type ValueType int
+
+// Possible values for the ValueType enum.
+const (
+ _ ValueType = iota
+ CounterValue
+ GaugeValue
+ UntypedValue
+)
+
+// valueFunc is a generic metric for simple values retrieved on collect time
+// from a function. It implements Metric and Collector. Its effective type is
+// determined by ValueType. This is a low-level building block used by the
+// library to back the implementations of CounterFunc, GaugeFunc, and
+// UntypedFunc.
+type valueFunc struct {
+ selfCollector
+
+ desc *Desc
+ valType ValueType
+ function func() float64
+ labelPairs []*dto.LabelPair
+}
+
+// newValueFunc returns a newly allocated valueFunc with the given Desc and
+// ValueType. 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 valueFunc is directly registered with Prometheus, the
+// provided function must be concurrency-safe.
+func newValueFunc(desc *Desc, valueType ValueType, function func() float64) *valueFunc {
+ result := &valueFunc{
+ desc: desc,
+ valType: valueType,
+ function: function,
+ labelPairs: makeLabelPairs(desc, nil),
+ }
+ result.init(result)
+ return result
+}
+
+func (v *valueFunc) Desc() *Desc {
+ return v.desc
+}
+
+func (v *valueFunc) Write(out *dto.Metric) error {
+ return populateMetric(v.valType, v.function(), v.labelPairs, out)
+}
+
+// NewConstMetric returns a metric with one fixed value that cannot be
+// changed. Users of this package will not have much use for it in regular
+// operations. However, when implementing custom Collectors, it is useful as a
+// throw-away metric that is generated on the fly to send it to Prometheus in
+// the Collect method. NewConstMetric returns an error if the length of
+// labelValues is not consistent with the variable labels in Desc or if Desc is
+// invalid.
+func NewConstMetric(desc *Desc, valueType ValueType, value float64, labelValues ...string) (Metric, error) {
+ if desc.err != nil {
+ return nil, desc.err
+ }
+ if err := validateLabelValues(labelValues, len(desc.variableLabels)); err != nil {
+ return nil, err
+ }
+ return &constMetric{
+ desc: desc,
+ valType: valueType,
+ val: value,
+ labelPairs: makeLabelPairs(desc, labelValues),
+ }, nil
+}
+
+// MustNewConstMetric is a version of NewConstMetric that panics where
+// NewConstMetric would have returned an error.
+func MustNewConstMetric(desc *Desc, valueType ValueType, value float64, labelValues ...string) Metric {
+ m, err := NewConstMetric(desc, valueType, value, labelValues...)
+ if err != nil {
+ panic(err)
+ }
+ return m
+}
+
+type constMetric struct {
+ desc *Desc
+ valType ValueType
+ val float64
+ labelPairs []*dto.LabelPair
+}
+
+func (m *constMetric) Desc() *Desc {
+ return m.desc
+}
+
+func (m *constMetric) Write(out *dto.Metric) error {
+ return populateMetric(m.valType, m.val, m.labelPairs, out)
+}
+
+func populateMetric(
+ t ValueType,
+ v float64,
+ labelPairs []*dto.LabelPair,
+ m *dto.Metric,
+) error {
+ m.Label = labelPairs
+ switch t {
+ case CounterValue:
+ m.Counter = &dto.Counter{Value: proto.Float64(v)}
+ case GaugeValue:
+ m.Gauge = &dto.Gauge{Value: proto.Float64(v)}
+ case UntypedValue:
+ m.Untyped = &dto.Untyped{Value: proto.Float64(v)}
+ default:
+ return fmt.Errorf("encountered unknown type %v", t)
+ }
+ return nil
+}
+
+func makeLabelPairs(desc *Desc, labelValues []string) []*dto.LabelPair {
+ totalLen := len(desc.variableLabels) + len(desc.constLabelPairs)
+ if totalLen == 0 {
+ // Super fast path.
+ return nil
+ }
+ if len(desc.variableLabels) == 0 {
+ // Moderately fast path.
+ return desc.constLabelPairs
+ }
+ labelPairs := make([]*dto.LabelPair, 0, totalLen)
+ for i, n := range desc.variableLabels {
+ labelPairs = append(labelPairs, &dto.LabelPair{
+ Name: proto.String(n),
+ Value: proto.String(labelValues[i]),
+ })
+ }
+ labelPairs = append(labelPairs, desc.constLabelPairs...)
+ sort.Sort(labelPairSorter(labelPairs))
+ return labelPairs
+}