[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/vec.go b/vendor/github.com/prometheus/client_golang/prometheus/vec.go
new file mode 100644
index 0000000..14ed9e8
--- /dev/null
+++ b/vendor/github.com/prometheus/client_golang/prometheus/vec.go
@@ -0,0 +1,472 @@
+// 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"
+ "sync"
+
+ "github.com/prometheus/common/model"
+)
+
+// metricVec is a Collector to bundle metrics of the same name that differ in
+// their label values. metricVec is not used directly (and therefore
+// unexported). It is used as a building block for implementations of vectors of
+// a given metric type, like GaugeVec, CounterVec, SummaryVec, and HistogramVec.
+// It also handles label currying. It uses basicMetricVec internally.
+type metricVec struct {
+ *metricMap
+
+ curry []curriedLabelValue
+
+ // hashAdd and hashAddByte can be replaced for testing collision handling.
+ hashAdd func(h uint64, s string) uint64
+ hashAddByte func(h uint64, b byte) uint64
+}
+
+// newMetricVec returns an initialized metricVec.
+func newMetricVec(desc *Desc, newMetric func(lvs ...string) Metric) *metricVec {
+ return &metricVec{
+ metricMap: &metricMap{
+ metrics: map[uint64][]metricWithLabelValues{},
+ desc: desc,
+ newMetric: newMetric,
+ },
+ hashAdd: hashAdd,
+ hashAddByte: hashAddByte,
+ }
+}
+
+// DeleteLabelValues removes the metric where the variable labels are the same
+// as those passed in as labels (same order as the VariableLabels in Desc). It
+// returns true if a metric was deleted.
+//
+// It is not an error if the number of label values is not the same as the
+// number of VariableLabels in Desc. However, such inconsistent label count can
+// never match an actual metric, so the method will always return false in that
+// case.
+//
+// Note that for more than one label value, this method is prone to mistakes
+// caused by an incorrect order of arguments. Consider Delete(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).
+// See also the CounterVec example.
+func (m *metricVec) DeleteLabelValues(lvs ...string) bool {
+ h, err := m.hashLabelValues(lvs)
+ if err != nil {
+ return false
+ }
+
+ return m.metricMap.deleteByHashWithLabelValues(h, lvs, m.curry)
+}
+
+// Delete deletes the metric where the variable labels are the same as those
+// passed in as labels. It returns true if a metric was deleted.
+//
+// It is not an error if the number and names of the Labels are inconsistent
+// with those of the VariableLabels in Desc. However, such inconsistent Labels
+// can never match an actual metric, so the method will always return false in
+// that case.
+//
+// This method is used for the same purpose as DeleteLabelValues(...string). See
+// there for pros and cons of the two methods.
+func (m *metricVec) Delete(labels Labels) bool {
+ h, err := m.hashLabels(labels)
+ if err != nil {
+ return false
+ }
+
+ return m.metricMap.deleteByHashWithLabels(h, labels, m.curry)
+}
+
+func (m *metricVec) curryWith(labels Labels) (*metricVec, error) {
+ var (
+ newCurry []curriedLabelValue
+ oldCurry = m.curry
+ iCurry int
+ )
+ for i, label := range m.desc.variableLabels {
+ val, ok := labels[label]
+ if iCurry < len(oldCurry) && oldCurry[iCurry].index == i {
+ if ok {
+ return nil, fmt.Errorf("label name %q is already curried", label)
+ }
+ newCurry = append(newCurry, oldCurry[iCurry])
+ iCurry++
+ } else {
+ if !ok {
+ continue // Label stays uncurried.
+ }
+ newCurry = append(newCurry, curriedLabelValue{i, val})
+ }
+ }
+ if l := len(oldCurry) + len(labels) - len(newCurry); l > 0 {
+ return nil, fmt.Errorf("%d unknown label(s) found during currying", l)
+ }
+
+ return &metricVec{
+ metricMap: m.metricMap,
+ curry: newCurry,
+ hashAdd: m.hashAdd,
+ hashAddByte: m.hashAddByte,
+ }, nil
+}
+
+func (m *metricVec) getMetricWithLabelValues(lvs ...string) (Metric, error) {
+ h, err := m.hashLabelValues(lvs)
+ if err != nil {
+ return nil, err
+ }
+
+ return m.metricMap.getOrCreateMetricWithLabelValues(h, lvs, m.curry), nil
+}
+
+func (m *metricVec) getMetricWith(labels Labels) (Metric, error) {
+ h, err := m.hashLabels(labels)
+ if err != nil {
+ return nil, err
+ }
+
+ return m.metricMap.getOrCreateMetricWithLabels(h, labels, m.curry), nil
+}
+
+func (m *metricVec) hashLabelValues(vals []string) (uint64, error) {
+ if err := validateLabelValues(vals, len(m.desc.variableLabels)-len(m.curry)); err != nil {
+ return 0, err
+ }
+
+ var (
+ h = hashNew()
+ curry = m.curry
+ iVals, iCurry int
+ )
+ for i := 0; i < len(m.desc.variableLabels); i++ {
+ if iCurry < len(curry) && curry[iCurry].index == i {
+ h = m.hashAdd(h, curry[iCurry].value)
+ iCurry++
+ } else {
+ h = m.hashAdd(h, vals[iVals])
+ iVals++
+ }
+ h = m.hashAddByte(h, model.SeparatorByte)
+ }
+ return h, nil
+}
+
+func (m *metricVec) hashLabels(labels Labels) (uint64, error) {
+ if err := validateValuesInLabels(labels, len(m.desc.variableLabels)-len(m.curry)); err != nil {
+ return 0, err
+ }
+
+ var (
+ h = hashNew()
+ curry = m.curry
+ iCurry int
+ )
+ for i, label := range m.desc.variableLabels {
+ val, ok := labels[label]
+ if iCurry < len(curry) && curry[iCurry].index == i {
+ if ok {
+ return 0, fmt.Errorf("label name %q is already curried", label)
+ }
+ h = m.hashAdd(h, curry[iCurry].value)
+ iCurry++
+ } else {
+ if !ok {
+ return 0, fmt.Errorf("label name %q missing in label map", label)
+ }
+ h = m.hashAdd(h, val)
+ }
+ h = m.hashAddByte(h, model.SeparatorByte)
+ }
+ return h, nil
+}
+
+// metricWithLabelValues provides the metric and its label values for
+// disambiguation on hash collision.
+type metricWithLabelValues struct {
+ values []string
+ metric Metric
+}
+
+// curriedLabelValue sets the curried value for a label at the given index.
+type curriedLabelValue struct {
+ index int
+ value string
+}
+
+// metricMap is a helper for metricVec and shared between differently curried
+// metricVecs.
+type metricMap struct {
+ mtx sync.RWMutex // Protects metrics.
+ metrics map[uint64][]metricWithLabelValues
+ desc *Desc
+ newMetric func(labelValues ...string) Metric
+}
+
+// Describe implements Collector. It will send exactly one Desc to the provided
+// channel.
+func (m *metricMap) Describe(ch chan<- *Desc) {
+ ch <- m.desc
+}
+
+// Collect implements Collector.
+func (m *metricMap) Collect(ch chan<- Metric) {
+ m.mtx.RLock()
+ defer m.mtx.RUnlock()
+
+ for _, metrics := range m.metrics {
+ for _, metric := range metrics {
+ ch <- metric.metric
+ }
+ }
+}
+
+// Reset deletes all metrics in this vector.
+func (m *metricMap) Reset() {
+ m.mtx.Lock()
+ defer m.mtx.Unlock()
+
+ for h := range m.metrics {
+ delete(m.metrics, h)
+ }
+}
+
+// deleteByHashWithLabelValues removes the metric from the hash bucket h. If
+// there are multiple matches in the bucket, use lvs to select a metric and
+// remove only that metric.
+func (m *metricMap) deleteByHashWithLabelValues(
+ h uint64, lvs []string, curry []curriedLabelValue,
+) bool {
+ m.mtx.Lock()
+ defer m.mtx.Unlock()
+
+ metrics, ok := m.metrics[h]
+ if !ok {
+ return false
+ }
+
+ i := findMetricWithLabelValues(metrics, lvs, curry)
+ if i >= len(metrics) {
+ return false
+ }
+
+ if len(metrics) > 1 {
+ m.metrics[h] = append(metrics[:i], metrics[i+1:]...)
+ } else {
+ delete(m.metrics, h)
+ }
+ return true
+}
+
+// deleteByHashWithLabels removes the metric from the hash bucket h. If there
+// are multiple matches in the bucket, use lvs to select a metric and remove
+// only that metric.
+func (m *metricMap) deleteByHashWithLabels(
+ h uint64, labels Labels, curry []curriedLabelValue,
+) bool {
+ m.mtx.Lock()
+ defer m.mtx.Unlock()
+
+ metrics, ok := m.metrics[h]
+ if !ok {
+ return false
+ }
+ i := findMetricWithLabels(m.desc, metrics, labels, curry)
+ if i >= len(metrics) {
+ return false
+ }
+
+ if len(metrics) > 1 {
+ m.metrics[h] = append(metrics[:i], metrics[i+1:]...)
+ } else {
+ delete(m.metrics, h)
+ }
+ return true
+}
+
+// getOrCreateMetricWithLabelValues retrieves the metric by hash and label value
+// or creates it and returns the new one.
+//
+// This function holds the mutex.
+func (m *metricMap) getOrCreateMetricWithLabelValues(
+ hash uint64, lvs []string, curry []curriedLabelValue,
+) Metric {
+ m.mtx.RLock()
+ metric, ok := m.getMetricWithHashAndLabelValues(hash, lvs, curry)
+ m.mtx.RUnlock()
+ if ok {
+ return metric
+ }
+
+ m.mtx.Lock()
+ defer m.mtx.Unlock()
+ metric, ok = m.getMetricWithHashAndLabelValues(hash, lvs, curry)
+ if !ok {
+ inlinedLVs := inlineLabelValues(lvs, curry)
+ metric = m.newMetric(inlinedLVs...)
+ m.metrics[hash] = append(m.metrics[hash], metricWithLabelValues{values: inlinedLVs, metric: metric})
+ }
+ return metric
+}
+
+// getOrCreateMetricWithLabelValues retrieves the metric by hash and label value
+// or creates it and returns the new one.
+//
+// This function holds the mutex.
+func (m *metricMap) getOrCreateMetricWithLabels(
+ hash uint64, labels Labels, curry []curriedLabelValue,
+) Metric {
+ m.mtx.RLock()
+ metric, ok := m.getMetricWithHashAndLabels(hash, labels, curry)
+ m.mtx.RUnlock()
+ if ok {
+ return metric
+ }
+
+ m.mtx.Lock()
+ defer m.mtx.Unlock()
+ metric, ok = m.getMetricWithHashAndLabels(hash, labels, curry)
+ if !ok {
+ lvs := extractLabelValues(m.desc, labels, curry)
+ metric = m.newMetric(lvs...)
+ m.metrics[hash] = append(m.metrics[hash], metricWithLabelValues{values: lvs, metric: metric})
+ }
+ return metric
+}
+
+// getMetricWithHashAndLabelValues gets a metric while handling possible
+// collisions in the hash space. Must be called while holding the read mutex.
+func (m *metricMap) getMetricWithHashAndLabelValues(
+ h uint64, lvs []string, curry []curriedLabelValue,
+) (Metric, bool) {
+ metrics, ok := m.metrics[h]
+ if ok {
+ if i := findMetricWithLabelValues(metrics, lvs, curry); i < len(metrics) {
+ return metrics[i].metric, true
+ }
+ }
+ return nil, false
+}
+
+// getMetricWithHashAndLabels gets a metric while handling possible collisions in
+// the hash space. Must be called while holding read mutex.
+func (m *metricMap) getMetricWithHashAndLabels(
+ h uint64, labels Labels, curry []curriedLabelValue,
+) (Metric, bool) {
+ metrics, ok := m.metrics[h]
+ if ok {
+ if i := findMetricWithLabels(m.desc, metrics, labels, curry); i < len(metrics) {
+ return metrics[i].metric, true
+ }
+ }
+ return nil, false
+}
+
+// findMetricWithLabelValues returns the index of the matching metric or
+// len(metrics) if not found.
+func findMetricWithLabelValues(
+ metrics []metricWithLabelValues, lvs []string, curry []curriedLabelValue,
+) int {
+ for i, metric := range metrics {
+ if matchLabelValues(metric.values, lvs, curry) {
+ return i
+ }
+ }
+ return len(metrics)
+}
+
+// findMetricWithLabels returns the index of the matching metric or len(metrics)
+// if not found.
+func findMetricWithLabels(
+ desc *Desc, metrics []metricWithLabelValues, labels Labels, curry []curriedLabelValue,
+) int {
+ for i, metric := range metrics {
+ if matchLabels(desc, metric.values, labels, curry) {
+ return i
+ }
+ }
+ return len(metrics)
+}
+
+func matchLabelValues(values []string, lvs []string, curry []curriedLabelValue) bool {
+ if len(values) != len(lvs)+len(curry) {
+ return false
+ }
+ var iLVs, iCurry int
+ for i, v := range values {
+ if iCurry < len(curry) && curry[iCurry].index == i {
+ if v != curry[iCurry].value {
+ return false
+ }
+ iCurry++
+ continue
+ }
+ if v != lvs[iLVs] {
+ return false
+ }
+ iLVs++
+ }
+ return true
+}
+
+func matchLabels(desc *Desc, values []string, labels Labels, curry []curriedLabelValue) bool {
+ if len(values) != len(labels)+len(curry) {
+ return false
+ }
+ iCurry := 0
+ for i, k := range desc.variableLabels {
+ if iCurry < len(curry) && curry[iCurry].index == i {
+ if values[i] != curry[iCurry].value {
+ return false
+ }
+ iCurry++
+ continue
+ }
+ if values[i] != labels[k] {
+ return false
+ }
+ }
+ return true
+}
+
+func extractLabelValues(desc *Desc, labels Labels, curry []curriedLabelValue) []string {
+ labelValues := make([]string, len(labels)+len(curry))
+ iCurry := 0
+ for i, k := range desc.variableLabels {
+ if iCurry < len(curry) && curry[iCurry].index == i {
+ labelValues[i] = curry[iCurry].value
+ iCurry++
+ continue
+ }
+ labelValues[i] = labels[k]
+ }
+ return labelValues
+}
+
+func inlineLabelValues(lvs []string, curry []curriedLabelValue) []string {
+ labelValues := make([]string, len(lvs)+len(curry))
+ var iCurry, iLVs int
+ for i := range labelValues {
+ if iCurry < len(curry) && curry[iCurry].index == i {
+ labelValues[i] = curry[iCurry].value
+ iCurry++
+ continue
+ }
+ labelValues[i] = lvs[iLVs]
+ iLVs++
+ }
+ return labelValues
+}