diff options
Diffstat (limited to 'vendor/github.com/prometheus/client_golang/prometheus/vec.go')
| -rw-r--r-- | vendor/github.com/prometheus/client_golang/prometheus/vec.go | 143 |
1 files changed, 51 insertions, 92 deletions
diff --git a/vendor/github.com/prometheus/client_golang/prometheus/vec.go b/vendor/github.com/prometheus/client_golang/prometheus/vec.go index 7f3eef9..65d13fe 100644 --- a/vendor/github.com/prometheus/client_golang/prometheus/vec.go +++ b/vendor/github.com/prometheus/client_golang/prometheus/vec.go @@ -20,12 +20,12 @@ import ( "github.com/prometheus/common/model" ) -// MetricVec is a Collector to bundle metrics of the same name that -// differ in their label values. MetricVec is usually not used directly but as a -// building block for implementations of vectors of a given metric -// type. GaugeVec, CounterVec, SummaryVec, and UntypedVec are examples already -// provided in this package. -type MetricVec struct { +// 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, HistogramVec, and +// UntypedVec. +type metricVec struct { mtx sync.RWMutex // Protects the children. children map[uint64][]metricWithLabelValues desc *Desc @@ -35,10 +35,9 @@ type MetricVec struct { hashAddByte func(h uint64, b byte) uint64 } -// newMetricVec returns an initialized MetricVec. The concrete value is -// returned for embedding into another struct. -func newMetricVec(desc *Desc, newMetric func(lvs ...string) Metric) *MetricVec { - return &MetricVec{ +// newMetricVec returns an initialized metricVec. +func newMetricVec(desc *Desc, newMetric func(lvs ...string) Metric) *metricVec { + return &metricVec{ children: map[uint64][]metricWithLabelValues{}, desc: desc, newMetric: newMetric, @@ -56,12 +55,12 @@ type metricWithLabelValues struct { // Describe implements Collector. The length of the returned slice // is always one. -func (m *MetricVec) Describe(ch chan<- *Desc) { +func (m *metricVec) Describe(ch chan<- *Desc) { ch <- m.desc } // Collect implements Collector. -func (m *MetricVec) Collect(ch chan<- Metric) { +func (m *metricVec) Collect(ch chan<- Metric) { m.mtx.RLock() defer m.mtx.RUnlock() @@ -72,31 +71,7 @@ func (m *MetricVec) Collect(ch chan<- Metric) { } } -// GetMetricWithLabelValues returns the Metric 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 Metric is created. -// -// It is possible to call this method without using the returned Metric to only -// create the new Metric but leave it at its start value (e.g. a Summary or -// Histogram without any observations). See also the SummaryVec example. -// -// Keeping the Metric 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 Metric from the MetricVec. In that case, the -// Metric will still exist, but it will not be exported anymore, even if a -// Metric 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. -// -// 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). -// See also the GaugeVec example. -func (m *MetricVec) GetMetricWithLabelValues(lvs ...string) (Metric, error) { +func (m *metricVec) getMetricWithLabelValues(lvs ...string) (Metric, error) { h, err := m.hashLabelValues(lvs) if err != nil { return nil, err @@ -105,19 +80,7 @@ func (m *MetricVec) GetMetricWithLabelValues(lvs ...string) (Metric, error) { return m.getOrCreateMetricWithLabelValues(h, lvs), nil } -// GetMetricWith returns the Metric 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 Metric is created. Implications of -// creating a Metric without using it and keeping the Metric 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. -// -// This method is used for the same purpose as -// GetMetricWithLabelValues(...string). See there for pros and cons of the two -// methods. -func (m *MetricVec) GetMetricWith(labels Labels) (Metric, error) { +func (m *metricVec) getMetricWith(labels Labels) (Metric, error) { h, err := m.hashLabels(labels) if err != nil { return nil, err @@ -126,22 +89,16 @@ func (m *MetricVec) GetMetricWith(labels Labels) (Metric, error) { return m.getOrCreateMetricWithLabels(h, labels), nil } -// WithLabelValues works as GetMetricWithLabelValues, but panics if an error -// occurs. The method allows neat syntax like: -// httpReqs.WithLabelValues("404", "POST").Inc() -func (m *MetricVec) WithLabelValues(lvs ...string) Metric { - metric, err := m.GetMetricWithLabelValues(lvs...) +func (m *metricVec) withLabelValues(lvs ...string) Metric { + metric, err := m.getMetricWithLabelValues(lvs...) if err != nil { panic(err) } return metric } -// With works as GetMetricWith, but panics if an error occurs. The method allows -// neat syntax like: -// httpReqs.With(Labels{"status":"404", "method":"POST"}).Inc() -func (m *MetricVec) With(labels Labels) Metric { - metric, err := m.GetMetricWith(labels) +func (m *metricVec) with(labels Labels) Metric { + metric, err := m.getMetricWith(labels) if err != nil { panic(err) } @@ -153,8 +110,8 @@ func (m *MetricVec) With(labels Labels) Metric { // 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 +// 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 @@ -163,7 +120,7 @@ func (m *MetricVec) With(labels Labels) Metric { // 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 { +func (m *metricVec) DeleteLabelValues(lvs ...string) bool { m.mtx.Lock() defer m.mtx.Unlock() @@ -178,13 +135,13 @@ func (m *MetricVec) DeleteLabelValues(lvs ...string) bool { // 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 the Desc of the MetricVec. However, such -// inconsistent Labels can never match an actual Metric, so the method will -// always return false in that case. +// 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 { +func (m *metricVec) Delete(labels Labels) bool { m.mtx.Lock() defer m.mtx.Unlock() @@ -199,7 +156,7 @@ func (m *MetricVec) Delete(labels Labels) bool { // 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 *MetricVec) deleteByHashWithLabelValues(h uint64, lvs []string) bool { +func (m *metricVec) deleteByHashWithLabelValues(h uint64, lvs []string) bool { metrics, ok := m.children[h] if !ok { return false @@ -221,7 +178,7 @@ func (m *MetricVec) deleteByHashWithLabelValues(h uint64, lvs []string) bool { // 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 *MetricVec) deleteByHashWithLabels(h uint64, labels Labels) bool { +func (m *metricVec) deleteByHashWithLabels(h uint64, labels Labels) bool { metrics, ok := m.children[h] if !ok { return false @@ -240,7 +197,7 @@ func (m *MetricVec) deleteByHashWithLabels(h uint64, labels Labels) bool { } // Reset deletes all metrics in this vector. -func (m *MetricVec) Reset() { +func (m *metricVec) Reset() { m.mtx.Lock() defer m.mtx.Unlock() @@ -249,10 +206,11 @@ func (m *MetricVec) Reset() { } } -func (m *MetricVec) hashLabelValues(vals []string) (uint64, error) { - if len(vals) != len(m.desc.variableLabels) { - return 0, errInconsistentCardinality +func (m *metricVec) hashLabelValues(vals []string) (uint64, error) { + if err := validateLabelValues(vals, len(m.desc.variableLabels)); err != nil { + return 0, err } + h := hashNew() for _, val := range vals { h = m.hashAdd(h, val) @@ -261,10 +219,11 @@ func (m *MetricVec) hashLabelValues(vals []string) (uint64, error) { return h, nil } -func (m *MetricVec) hashLabels(labels Labels) (uint64, error) { - if len(labels) != len(m.desc.variableLabels) { - return 0, errInconsistentCardinality +func (m *metricVec) hashLabels(labels Labels) (uint64, error) { + if err := validateValuesInLabels(labels, len(m.desc.variableLabels)); err != nil { + return 0, err } + h := hashNew() for _, label := range m.desc.variableLabels { val, ok := labels[label] @@ -281,9 +240,9 @@ func (m *MetricVec) hashLabels(labels Labels) (uint64, error) { // or creates it and returns the new one. // // This function holds the mutex. -func (m *MetricVec) getOrCreateMetricWithLabelValues(hash uint64, lvs []string) Metric { +func (m *metricVec) getOrCreateMetricWithLabelValues(hash uint64, lvs []string) Metric { m.mtx.RLock() - metric, ok := m.getMetricWithLabelValues(hash, lvs) + metric, ok := m.getMetricWithHashAndLabelValues(hash, lvs) m.mtx.RUnlock() if ok { return metric @@ -291,7 +250,7 @@ func (m *MetricVec) getOrCreateMetricWithLabelValues(hash uint64, lvs []string) m.mtx.Lock() defer m.mtx.Unlock() - metric, ok = m.getMetricWithLabelValues(hash, lvs) + metric, ok = m.getMetricWithHashAndLabelValues(hash, lvs) if !ok { // Copy to avoid allocation in case wo don't go down this code path. copiedLVs := make([]string, len(lvs)) @@ -306,9 +265,9 @@ func (m *MetricVec) getOrCreateMetricWithLabelValues(hash uint64, lvs []string) // or creates it and returns the new one. // // This function holds the mutex. -func (m *MetricVec) getOrCreateMetricWithLabels(hash uint64, labels Labels) Metric { +func (m *metricVec) getOrCreateMetricWithLabels(hash uint64, labels Labels) Metric { m.mtx.RLock() - metric, ok := m.getMetricWithLabels(hash, labels) + metric, ok := m.getMetricWithHashAndLabels(hash, labels) m.mtx.RUnlock() if ok { return metric @@ -316,7 +275,7 @@ func (m *MetricVec) getOrCreateMetricWithLabels(hash uint64, labels Labels) Metr m.mtx.Lock() defer m.mtx.Unlock() - metric, ok = m.getMetricWithLabels(hash, labels) + metric, ok = m.getMetricWithHashAndLabels(hash, labels) if !ok { lvs := m.extractLabelValues(labels) metric = m.newMetric(lvs...) @@ -325,9 +284,9 @@ func (m *MetricVec) getOrCreateMetricWithLabels(hash uint64, labels Labels) Metr return metric } -// getMetricWithLabelValues gets a metric while handling possible collisions in -// the hash space. Must be called while holding read mutex. -func (m *MetricVec) getMetricWithLabelValues(h uint64, lvs []string) (Metric, bool) { +// getMetricWithHashAndLabelValues gets a metric while handling possible +// collisions in the hash space. Must be called while holding the read mutex. +func (m *metricVec) getMetricWithHashAndLabelValues(h uint64, lvs []string) (Metric, bool) { metrics, ok := m.children[h] if ok { if i := m.findMetricWithLabelValues(metrics, lvs); i < len(metrics) { @@ -337,9 +296,9 @@ func (m *MetricVec) getMetricWithLabelValues(h uint64, lvs []string) (Metric, bo return nil, false } -// getMetricWithLabels gets a metric while handling possible collisions in +// getMetricWithHashAndLabels gets a metric while handling possible collisions in // the hash space. Must be called while holding read mutex. -func (m *MetricVec) getMetricWithLabels(h uint64, labels Labels) (Metric, bool) { +func (m *metricVec) getMetricWithHashAndLabels(h uint64, labels Labels) (Metric, bool) { metrics, ok := m.children[h] if ok { if i := m.findMetricWithLabels(metrics, labels); i < len(metrics) { @@ -351,7 +310,7 @@ func (m *MetricVec) getMetricWithLabels(h uint64, labels Labels) (Metric, bool) // findMetricWithLabelValues returns the index of the matching metric or // len(metrics) if not found. -func (m *MetricVec) findMetricWithLabelValues(metrics []metricWithLabelValues, lvs []string) int { +func (m *metricVec) findMetricWithLabelValues(metrics []metricWithLabelValues, lvs []string) int { for i, metric := range metrics { if m.matchLabelValues(metric.values, lvs) { return i @@ -362,7 +321,7 @@ func (m *MetricVec) findMetricWithLabelValues(metrics []metricWithLabelValues, l // findMetricWithLabels returns the index of the matching metric or len(metrics) // if not found. -func (m *MetricVec) findMetricWithLabels(metrics []metricWithLabelValues, labels Labels) int { +func (m *metricVec) findMetricWithLabels(metrics []metricWithLabelValues, labels Labels) int { for i, metric := range metrics { if m.matchLabels(metric.values, labels) { return i @@ -371,7 +330,7 @@ func (m *MetricVec) findMetricWithLabels(metrics []metricWithLabelValues, labels return len(metrics) } -func (m *MetricVec) matchLabelValues(values []string, lvs []string) bool { +func (m *metricVec) matchLabelValues(values []string, lvs []string) bool { if len(values) != len(lvs) { return false } @@ -383,7 +342,7 @@ func (m *MetricVec) matchLabelValues(values []string, lvs []string) bool { return true } -func (m *MetricVec) matchLabels(values []string, labels Labels) bool { +func (m *metricVec) matchLabels(values []string, labels Labels) bool { if len(labels) != len(values) { return false } @@ -395,7 +354,7 @@ func (m *MetricVec) matchLabels(values []string, labels Labels) bool { return true } -func (m *MetricVec) extractLabelValues(labels Labels) []string { +func (m *metricVec) extractLabelValues(labels Labels) []string { labelValues := make([]string, len(labels)) for i, k := range m.desc.variableLabels { labelValues[i] = labels[k] |