diff options
Diffstat (limited to 'vendor/github.com/prometheus/client_golang/prometheus')
20 files changed, 1088 insertions, 669 deletions
diff --git a/vendor/github.com/prometheus/client_golang/prometheus/counter.go b/vendor/github.com/prometheus/client_golang/prometheus/counter.go index 273db5f..765e455 100644 --- a/vendor/github.com/prometheus/client_golang/prometheus/counter.go +++ b/vendor/github.com/prometheus/client_golang/prometheus/counter.go @@ -15,6 +15,10 @@ package prometheus import ( "errors" + "math" + "sync/atomic" + + dto "github.com/prometheus/client_model/go" ) // Counter is a Metric that represents a single numerical value that only ever @@ -42,6 +46,14 @@ type Counter interface { type CounterOpts Opts // NewCounter creates a new Counter based on the provided CounterOpts. +// +// The returned implementation tracks the counter value in two separate +// variables, a float64 and a uint64. The latter is used to track calls of the +// Inc method and calls of the Add method with a value that can be represented +// as a uint64. This allows atomic increments of the counter with optimal +// performance. (It is common to have an Inc call in very hot execution paths.) +// Both internal tracking values are added up in the Write method. This has to +// be taken into account when it comes to precision and overflow behavior. func NewCounter(opts CounterOpts) Counter { desc := NewDesc( BuildFQName(opts.Namespace, opts.Subsystem, opts.Name), @@ -49,20 +61,58 @@ func NewCounter(opts CounterOpts) Counter { nil, opts.ConstLabels, ) - result := &counter{value: value{desc: desc, valType: CounterValue, labelPairs: desc.constLabelPairs}} + result := &counter{desc: desc, labelPairs: desc.constLabelPairs} result.init(result) // Init self-collection. return result } type counter struct { - value + // valBits contains the bits of the represented float64 value, while + // valInt stores values that are exact integers. Both have to go first + // in the struct to guarantee alignment for atomic operations. + // http://golang.org/pkg/sync/atomic/#pkg-note-BUG + valBits uint64 + valInt uint64 + + selfCollector + desc *Desc + + labelPairs []*dto.LabelPair +} + +func (c *counter) Desc() *Desc { + return c.desc } func (c *counter) Add(v float64) { if v < 0 { panic(errors.New("counter cannot decrease in value")) } - c.value.Add(v) + ival := uint64(v) + if float64(ival) == v { + atomic.AddUint64(&c.valInt, ival) + return + } + + for { + oldBits := atomic.LoadUint64(&c.valBits) + newBits := math.Float64bits(math.Float64frombits(oldBits) + v) + if atomic.CompareAndSwapUint64(&c.valBits, oldBits, newBits) { + return + } + } +} + +func (c *counter) Inc() { + atomic.AddUint64(&c.valInt, 1) +} + +func (c *counter) Write(out *dto.Metric) error { + fval := math.Float64frombits(atomic.LoadUint64(&c.valBits)) + ival := atomic.LoadUint64(&c.valInt) + val := fval + float64(ival) + + return populateMetric(CounterValue, val, c.labelPairs, out) } // CounterVec is a Collector that bundles a set of Counters that all share the @@ -85,11 +135,10 @@ func NewCounterVec(opts CounterOpts, labelNames []string) *CounterVec { ) return &CounterVec{ metricVec: newMetricVec(desc, func(lvs ...string) Metric { - result := &counter{value: value{ - desc: desc, - valType: CounterValue, - labelPairs: makeLabelPairs(desc, lvs), - }} + if len(lvs) != len(desc.variableLabels) { + panic(errInconsistentCardinality) + } + result := &counter{desc: desc, labelPairs: makeLabelPairs(desc, lvs)} result.init(result) // Init self-collection. return result }), @@ -111,7 +160,7 @@ func NewCounterVec(opts CounterOpts, labelNames []string) *CounterVec { // Counter with the same label values is created later. // // An error is returned if the number of label values is not the same as the -// number of VariableLabels in Desc. +// 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 @@ -119,8 +168,8 @@ func NewCounterVec(opts CounterOpts, labelNames []string) *CounterVec { // 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 *CounterVec) GetMetricWithLabelValues(lvs ...string) (Counter, error) { - metric, err := m.metricVec.getMetricWithLabelValues(lvs...) +func (v *CounterVec) GetMetricWithLabelValues(lvs ...string) (Counter, error) { + metric, err := v.metricVec.getMetricWithLabelValues(lvs...) if metric != nil { return metric.(Counter), err } @@ -134,13 +183,13 @@ func (m *CounterVec) GetMetricWithLabelValues(lvs ...string) (Counter, error) { // 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. +// 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 (m *CounterVec) GetMetricWith(labels Labels) (Counter, error) { - metric, err := m.metricVec.getMetricWith(labels) +func (v *CounterVec) GetMetricWith(labels Labels) (Counter, error) { + metric, err := v.metricVec.getMetricWith(labels) if metric != nil { return metric.(Counter), err } @@ -148,18 +197,57 @@ func (m *CounterVec) GetMetricWith(labels Labels) (Counter, error) { } // WithLabelValues works as GetMetricWithLabelValues, but panics where -// GetMetricWithLabelValues would have returned an error. By not returning an -// error, WithLabelValues allows shortcuts like +// GetMetricWithLabelValues would have returned an error. Not returning an +// error allows shortcuts like // myVec.WithLabelValues("404", "GET").Add(42) -func (m *CounterVec) WithLabelValues(lvs ...string) Counter { - return m.metricVec.withLabelValues(lvs...).(Counter) +func (v *CounterVec) WithLabelValues(lvs ...string) Counter { + c, err := v.GetMetricWithLabelValues(lvs...) + if err != nil { + panic(err) + } + return c } // With works as GetMetricWith, but panics where GetMetricWithLabels would have -// returned an error. By not returning an error, With allows shortcuts like -// myVec.With(Labels{"code": "404", "method": "GET"}).Add(42) -func (m *CounterVec) With(labels Labels) Counter { - return m.metricVec.with(labels).(Counter) +// returned an error. Not returning an error allows shortcuts like +// myVec.With(prometheus.Labels{"code": "404", "method": "GET"}).Add(42) +func (v *CounterVec) With(labels Labels) Counter { + c, err := v.GetMetricWith(labels) + if err != nil { + panic(err) + } + return c +} + +// 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 CounterVec 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 *CounterVec) CurryWith(labels Labels) (*CounterVec, error) { + vec, err := v.curryWith(labels) + if vec != nil { + return &CounterVec{vec}, err + } + return nil, err +} + +// MustCurryWith works as CurryWith but panics where CurryWith would have +// returned an error. +func (v *CounterVec) MustCurryWith(labels Labels) *CounterVec { + vec, err := v.CurryWith(labels) + if err != nil { + panic(err) + } + return vec } // CounterFunc is a Counter whose value is determined at collect time by calling a diff --git a/vendor/github.com/prometheus/client_golang/prometheus/desc.go b/vendor/github.com/prometheus/client_golang/prometheus/desc.go index 920abc9..4a755b0 100644 --- a/vendor/github.com/prometheus/client_golang/prometheus/desc.go +++ b/vendor/github.com/prometheus/client_golang/prometheus/desc.go @@ -73,8 +73,7 @@ type Desc struct { // and therefore not part of the Desc. (They are managed within the Metric.) // // For constLabels, the label values are constant. Therefore, they are fully -// specified in the Desc. See the Opts documentation for the implications of -// constant labels. +// specified in the Desc. See the Collector example for a usage pattern. func NewDesc(fqName, help string, variableLabels []string, constLabels Labels) *Desc { d := &Desc{ fqName: fqName, diff --git a/vendor/github.com/prometheus/client_golang/prometheus/doc.go b/vendor/github.com/prometheus/client_golang/prometheus/doc.go index 36ef155..83c3657 100644 --- a/vendor/github.com/prometheus/client_golang/prometheus/doc.go +++ b/vendor/github.com/prometheus/client_golang/prometheus/doc.go @@ -11,10 +11,12 @@ // See the License for the specific language governing permissions and // limitations under the License. -// Package prometheus provides metrics primitives to instrument code for -// monitoring. It also offers a registry for metrics. Sub-packages allow to -// expose the registered metrics via HTTP (package promhttp) or push them to a -// Pushgateway (package push). +// Package prometheus is the core instrumentation package. It provides metrics +// primitives to instrument code for monitoring. It also offers a registry for +// metrics. Sub-packages allow to expose the registered metrics via HTTP +// (package promhttp) or push them to a Pushgateway (package push). There is +// also a sub-package promauto, which provides metrics constructors with +// automatic registration. // // All exported functions and methods are safe to be used concurrently unless // specified otherwise. @@ -72,7 +74,10 @@ // The number of exported identifiers in this package might appear a bit // overwhelming. However, in addition to the basic plumbing shown in the example // above, you only need to understand the different metric types and their -// vector versions for basic usage. +// vector versions for basic usage. Furthermore, if you are not concerned with +// fine-grained control of when and how to register metrics with the registry, +// have a look at the promauto package, which will effectively allow you to +// ignore registration altogether in simple cases. // // Above, you have already touched the Counter and the Gauge. There are two more // advanced metric types: the Summary and Histogram. A more thorough description diff --git a/vendor/github.com/prometheus/client_golang/prometheus/gauge.go b/vendor/github.com/prometheus/client_golang/prometheus/gauge.go index 13064da..17c72d7 100644 --- a/vendor/github.com/prometheus/client_golang/prometheus/gauge.go +++ b/vendor/github.com/prometheus/client_golang/prometheus/gauge.go @@ -13,6 +13,14 @@ 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. // @@ -48,13 +56,74 @@ type Gauge interface { 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 { - return newValue(NewDesc( + desc := NewDesc( BuildFQName(opts.Namespace, opts.Subsystem, opts.Name), opts.Help, nil, opts.ConstLabels, - ), GaugeValue, 0) + ) + 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 @@ -77,7 +146,12 @@ func NewGaugeVec(opts GaugeOpts, labelNames []string) *GaugeVec { ) return &GaugeVec{ metricVec: newMetricVec(desc, func(lvs ...string) Metric { - return newValue(desc, GaugeValue, 0, lvs...) + if len(lvs) != len(desc.variableLabels) { + panic(errInconsistentCardinality) + } + result := &gauge{desc: desc, labelPairs: makeLabelPairs(desc, lvs)} + result.init(result) // Init self-collection. + return result }), } } @@ -98,15 +172,15 @@ func NewGaugeVec(opts GaugeOpts, labelNames []string) *GaugeVec { // example. // // An error is returned if the number of label values is not the same as the -// number of VariableLabels in Desc. +// 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 (m *GaugeVec) GetMetricWithLabelValues(lvs ...string) (Gauge, error) { - metric, err := m.metricVec.getMetricWithLabelValues(lvs...) +func (v *GaugeVec) GetMetricWithLabelValues(lvs ...string) (Gauge, error) { + metric, err := v.metricVec.getMetricWithLabelValues(lvs...) if metric != nil { return metric.(Gauge), err } @@ -120,13 +194,13 @@ func (m *GaugeVec) GetMetricWithLabelValues(lvs ...string) (Gauge, error) { // 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. +// 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 (m *GaugeVec) GetMetricWith(labels Labels) (Gauge, error) { - metric, err := m.metricVec.getMetricWith(labels) +func (v *GaugeVec) GetMetricWith(labels Labels) (Gauge, error) { + metric, err := v.metricVec.getMetricWith(labels) if metric != nil { return metric.(Gauge), err } @@ -134,18 +208,57 @@ func (m *GaugeVec) GetMetricWith(labels Labels) (Gauge, error) { } // WithLabelValues works as GetMetricWithLabelValues, but panics where -// GetMetricWithLabelValues would have returned an error. By not returning an -// error, WithLabelValues allows shortcuts like +// GetMetricWithLabelValues would have returned an error. Not returning an +// error allows shortcuts like // myVec.WithLabelValues("404", "GET").Add(42) -func (m *GaugeVec) WithLabelValues(lvs ...string) Gauge { - return m.metricVec.withLabelValues(lvs...).(Gauge) +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. By not returning an error, With allows shortcuts like -// myVec.With(Labels{"code": "404", "method": "GET"}).Add(42) -func (m *GaugeVec) With(labels Labels) Gauge { - return m.metricVec.with(labels).(Gauge) +// 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 diff --git a/vendor/github.com/prometheus/client_golang/prometheus/go_collector.go b/vendor/github.com/prometheus/client_golang/prometheus/go_collector.go index 096454a..0440bd1 100644 --- a/vendor/github.com/prometheus/client_golang/prometheus/go_collector.go +++ b/vendor/github.com/prometheus/client_golang/prometheus/go_collector.go @@ -17,8 +17,12 @@ type goCollector struct { metrics memStatsMetrics } -// NewGoCollector returns a collector which exports metrics about the current -// go process. +// NewGoCollector returns a collector which exports metrics about the current Go +// process. This includes memory stats. To collect those, runtime.ReadMemStats +// is called. This causes a stop-the-world, which is very short with Go1.9+ +// (~25µs). However, with older Go versions, the stop-the-world duration depends +// on the heap size and can be quite significant (~1.7 ms/GiB as per +// https://go-review.googlesource.com/c/go/+/34937). func NewGoCollector() Collector { return &goCollector{ goroutinesDesc: NewDesc( @@ -265,7 +269,7 @@ func (c *goCollector) Collect(ch chan<- Metric) { quantiles[float64(idx+1)/float64(len(stats.PauseQuantiles)-1)] = pq.Seconds() } quantiles[0.0] = stats.PauseQuantiles[0].Seconds() - ch <- MustNewConstSummary(c.gcDesc, uint64(stats.NumGC), float64(stats.PauseTotal.Seconds()), quantiles) + ch <- MustNewConstSummary(c.gcDesc, uint64(stats.NumGC), stats.PauseTotal.Seconds(), quantiles) ch <- MustNewConstMetric(c.goInfoDesc, GaugeValue, 1) diff --git a/vendor/github.com/prometheus/client_golang/prometheus/histogram.go b/vendor/github.com/prometheus/client_golang/prometheus/histogram.go index 6cc6e68..331783a 100644 --- a/vendor/github.com/prometheus/client_golang/prometheus/histogram.go +++ b/vendor/github.com/prometheus/client_golang/prometheus/histogram.go @@ -126,23 +126,16 @@ type HistogramOpts struct { // string. Help string - // ConstLabels are used to attach fixed labels to this - // Histogram. Histograms with the same fully-qualified name must have the - // same label names in their ConstLabels. + // ConstLabels are used to attach fixed labels to this metric. Metrics + // with the same fully-qualified name must have the same label names in + // their ConstLabels. // - // Note that in most cases, labels have a value that varies during the - // lifetime of a process. Those labels are usually managed with a - // HistogramVec. ConstLabels serve only special purposes. One is for the - // special case where the value of a label does not change during the - // lifetime of a process, e.g. if the revision of the running binary is - // put into a label. Another, more advanced purpose is if more than one - // Collector needs to collect Histograms with the same fully-qualified - // name. In that case, those Summaries must differ in the values of - // their ConstLabels. See the Collector examples. - // - // If the value of a label never changes (not even between binaries), - // that label most likely should not be a label at all (but part of the - // metric name). + // ConstLabels are only used rarely. In particular, do not use them to + // attach the same labels to all your metrics. Those use cases are + // better covered by target labels set by the scraping Prometheus + // server, or by one specific metric (e.g. a build_info or a + // machine_role metric). See also + // https://prometheus.io/docs/instrumenting/writing_exporters/#target-labels,-not-static-scraped-labels ConstLabels Labels // Buckets defines the buckets into which observations are counted. Each @@ -322,7 +315,7 @@ func NewHistogramVec(opts HistogramOpts, labelNames []string) *HistogramVec { // example. // // An error is returned if the number of label values is not the same as the -// number of VariableLabels in Desc. +// 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 @@ -330,8 +323,8 @@ func NewHistogramVec(opts HistogramOpts, labelNames []string) *HistogramVec { // 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 *HistogramVec) GetMetricWithLabelValues(lvs ...string) (Observer, error) { - metric, err := m.metricVec.getMetricWithLabelValues(lvs...) +func (v *HistogramVec) GetMetricWithLabelValues(lvs ...string) (Observer, error) { + metric, err := v.metricVec.getMetricWithLabelValues(lvs...) if metric != nil { return metric.(Observer), err } @@ -345,13 +338,13 @@ func (m *HistogramVec) GetMetricWithLabelValues(lvs ...string) (Observer, error) // 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. +// 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 (m *HistogramVec) GetMetricWith(labels Labels) (Observer, error) { - metric, err := m.metricVec.getMetricWith(labels) +func (v *HistogramVec) GetMetricWith(labels Labels) (Observer, error) { + metric, err := v.metricVec.getMetricWith(labels) if metric != nil { return metric.(Observer), err } @@ -359,18 +352,57 @@ func (m *HistogramVec) GetMetricWith(labels Labels) (Observer, error) { } // WithLabelValues works as GetMetricWithLabelValues, but panics where -// GetMetricWithLabelValues would have returned an error. By not returning an -// error, WithLabelValues allows shortcuts like +// GetMetricWithLabelValues would have returned an error. Not returning an +// error allows shortcuts like // myVec.WithLabelValues("404", "GET").Observe(42.21) -func (m *HistogramVec) WithLabelValues(lvs ...string) Observer { - return m.metricVec.withLabelValues(lvs...).(Observer) +func (v *HistogramVec) WithLabelValues(lvs ...string) Observer { + h, err := v.GetMetricWithLabelValues(lvs...) + if err != nil { + panic(err) + } + return h } -// With works as GetMetricWith, but panics where GetMetricWithLabels would have -// returned an error. By not returning an error, With allows shortcuts like -// myVec.With(Labels{"code": "404", "method": "GET"}).Observe(42.21) -func (m *HistogramVec) With(labels Labels) Observer { - return m.metricVec.with(labels).(Observer) +// 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"}).Observe(42.21) +func (v *HistogramVec) With(labels Labels) Observer { + h, err := v.GetMetricWith(labels) + if err != nil { + panic(err) + } + return h +} + +// 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 HistogramVec 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 *HistogramVec) CurryWith(labels Labels) (ObserverVec, error) { + vec, err := v.curryWith(labels) + if vec != nil { + return &HistogramVec{vec}, err + } + return nil, err +} + +// MustCurryWith works as CurryWith but panics where CurryWith would have +// returned an error. +func (v *HistogramVec) MustCurryWith(labels Labels) ObserverVec { + vec, err := v.CurryWith(labels) + if err != nil { + panic(err) + } + return vec } type constHistogram struct { diff --git a/vendor/github.com/prometheus/client_golang/prometheus/http.go b/vendor/github.com/prometheus/client_golang/prometheus/http.go index bfee5c6..4d08154 100644 --- a/vendor/github.com/prometheus/client_golang/prometheus/http.go +++ b/vendor/github.com/prometheus/client_golang/prometheus/http.go @@ -61,9 +61,8 @@ func giveBuf(buf *bytes.Buffer) { // name). // // Deprecated: Please note the issues described in the doc comment of -// InstrumentHandler. You might want to consider using promhttp.Handler instead -// (which is not instrumented, but can be instrumented with the tooling provided -// in package promhttp). +// InstrumentHandler. You might want to consider using +// promhttp.InstrumentedHandler instead. func Handler() http.Handler { return InstrumentHandler("prometheus", UninstrumentedHandler()) } @@ -116,7 +115,7 @@ func decorateWriter(request *http.Request, writer io.Writer) (io.Writer, string) header := request.Header.Get(acceptEncodingHeader) parts := strings.Split(header, ",") for _, part := range parts { - part := strings.TrimSpace(part) + part = strings.TrimSpace(part) if part == "gzip" || strings.HasPrefix(part, "gzip;") { return gzip.NewWriter(writer), "gzip" } @@ -140,16 +139,6 @@ var now nower = nowFunc(func() time.Time { return time.Now() }) -func nowSeries(t ...time.Time) nower { - return nowFunc(func() time.Time { - defer func() { - t = t[1:] - }() - - return t[0] - }) -} - // InstrumentHandler wraps the given HTTP handler for instrumentation. It // registers four metric collectors (if not already done) and reports HTTP // metrics to the (newly or already) registered collectors: http_requests_total @@ -353,10 +342,9 @@ func computeApproximateRequestSize(r *http.Request) <-chan int { type responseWriterDelegator struct { http.ResponseWriter - handler, method string - status int - written int64 - wroteHeader bool + status int + written int64 + wroteHeader bool } func (r *responseWriterDelegator) WriteHeader(code int) { diff --git a/vendor/github.com/prometheus/client_golang/prometheus/metric.go b/vendor/github.com/prometheus/client_golang/prometheus/metric.go index d4063d9..76035bc 100644 --- a/vendor/github.com/prometheus/client_golang/prometheus/metric.go +++ b/vendor/github.com/prometheus/client_golang/prometheus/metric.go @@ -79,20 +79,12 @@ type Opts struct { // with the same fully-qualified name must have the same label names in // their ConstLabels. // - // Note that in most cases, labels have a value that varies during the - // lifetime of a process. Those labels are usually managed with a metric - // vector collector (like CounterVec, GaugeVec, UntypedVec). ConstLabels - // serve only special purposes. One is for the special case where the - // value of a label does not change during the lifetime of a process, - // e.g. if the revision of the running binary is put into a - // label. Another, more advanced purpose is if more than one Collector - // needs to collect Metrics with the same fully-qualified name. In that - // case, those Metrics must differ in the values of their - // ConstLabels. See the Collector examples. - // - // If the value of a label never changes (not even between binaries), - // that label most likely should not be a label at all (but part of the - // metric name). + // ConstLabels are only used rarely. In particular, do not use them to + // attach the same labels to all your metrics. Those use cases are + // better covered by target labels set by the scraping Prometheus + // server, or by one specific metric (e.g. a build_info or a + // machine_role metric). See also + // https://prometheus.io/docs/instrumenting/writing_exporters/#target-labels,-not-static-scraped-labels ConstLabels Labels } @@ -135,20 +127,6 @@ func (s LabelPairSorter) Less(i, j int) bool { return s[i].GetName() < s[j].GetName() } -type hashSorter []uint64 - -func (s hashSorter) Len() int { - return len(s) -} - -func (s hashSorter) Swap(i, j int) { - s[i], s[j] = s[j], s[i] -} - -func (s hashSorter) Less(i, j int) bool { - return s[i] < s[j] -} - type invalidMetric struct { desc *Desc err error diff --git a/vendor/github.com/prometheus/client_golang/prometheus/observer.go b/vendor/github.com/prometheus/client_golang/prometheus/observer.go index b0520e8..5806cd0 100644 --- a/vendor/github.com/prometheus/client_golang/prometheus/observer.go +++ b/vendor/github.com/prometheus/client_golang/prometheus/observer.go @@ -45,6 +45,8 @@ type ObserverVec interface { GetMetricWithLabelValues(lvs ...string) (Observer, error) With(Labels) Observer WithLabelValues(...string) Observer + CurryWith(Labels) (ObserverVec, error) + MustCurryWith(Labels) ObserverVec Collector } diff --git a/vendor/github.com/prometheus/client_golang/prometheus/process_collector.go b/vendor/github.com/prometheus/client_golang/prometheus/process_collector.go index 94b2553..b80adc6 100644 --- a/vendor/github.com/prometheus/client_golang/prometheus/process_collector.go +++ b/vendor/github.com/prometheus/client_golang/prometheus/process_collector.go @@ -16,7 +16,6 @@ package prometheus import "github.com/prometheus/procfs" type processCollector struct { - pid int collectFn func(chan<- Metric) pidFn func() (int, error) cpuTotal *Desc @@ -26,8 +25,11 @@ type processCollector struct { } // NewProcessCollector returns a collector which exports the current state of -// process metrics including cpu, memory and file descriptor usage as well as -// the process start time for the given process id under the given namespace. +// process metrics including CPU, memory and file descriptor usage as well as +// the process start time for the given process ID under the given namespace. +// +// Currently, the collector depends on a Linux-style proc filesystem and +// therefore only exports metrics for Linux. func NewProcessCollector(pid int, namespace string) Collector { return NewProcessCollectorPIDFn( func() (int, error) { return pid, nil }, @@ -35,11 +37,8 @@ func NewProcessCollector(pid int, namespace string) Collector { ) } -// NewProcessCollectorPIDFn returns a collector which exports the current state -// of process metrics including cpu, memory and file descriptor usage as well -// as the process start time under the given namespace. The given pidFn is -// called on each collect and is used to determine the process to export -// metrics for. +// NewProcessCollectorPIDFn works like NewProcessCollector but the process ID is +// determined on each collect anew by calling the given pidFn function. func NewProcessCollectorPIDFn( pidFn func() (int, error), namespace string, diff --git a/vendor/github.com/prometheus/client_golang/prometheus/promhttp/delegator.go b/vendor/github.com/prometheus/client_golang/prometheus/promhttp/delegator.go index 5ee095b..9c1c66d 100644 --- a/vendor/github.com/prometheus/client_golang/prometheus/promhttp/delegator.go +++ b/vendor/github.com/prometheus/client_golang/prometheus/promhttp/delegator.go @@ -102,10 +102,10 @@ func init() { return d } pickDelegator[closeNotifier] = func(d *responseWriterDelegator) delegator { // 1 - return closeNotifierDelegator{d} + return &closeNotifierDelegator{d} } pickDelegator[flusher] = func(d *responseWriterDelegator) delegator { // 2 - return flusherDelegator{d} + return &flusherDelegator{d} } pickDelegator[flusher+closeNotifier] = func(d *responseWriterDelegator) delegator { // 3 return struct { @@ -115,7 +115,7 @@ func init() { }{d, &flusherDelegator{d}, &closeNotifierDelegator{d}} } pickDelegator[hijacker] = func(d *responseWriterDelegator) delegator { // 4 - return hijackerDelegator{d} + return &hijackerDelegator{d} } pickDelegator[hijacker+closeNotifier] = func(d *responseWriterDelegator) delegator { // 5 return struct { diff --git a/vendor/github.com/prometheus/client_golang/prometheus/promhttp/delegator_1_8.go b/vendor/github.com/prometheus/client_golang/prometheus/promhttp/delegator_1_8.go index f4d386f..75a905e 100644 --- a/vendor/github.com/prometheus/client_golang/prometheus/promhttp/delegator_1_8.go +++ b/vendor/github.com/prometheus/client_golang/prometheus/promhttp/delegator_1_8.go @@ -28,7 +28,7 @@ func (d *pusherDelegator) Push(target string, opts *http.PushOptions) error { func init() { pickDelegator[pusher] = func(d *responseWriterDelegator) delegator { // 16 - return pusherDelegator{d} + return &pusherDelegator{d} } pickDelegator[pusher+closeNotifier] = func(d *responseWriterDelegator) delegator { // 17 return struct { diff --git a/vendor/github.com/prometheus/client_golang/prometheus/promhttp/http.go b/vendor/github.com/prometheus/client_golang/prometheus/promhttp/http.go index 2d67f24..0135737 100644 --- a/vendor/github.com/prometheus/client_golang/prometheus/promhttp/http.go +++ b/vendor/github.com/prometheus/client_golang/prometheus/promhttp/http.go @@ -39,6 +39,7 @@ import ( "net/http" "strings" "sync" + "time" "github.com/prometheus/common/expfmt" @@ -67,21 +68,51 @@ func giveBuf(buf *bytes.Buffer) { bufPool.Put(buf) } -// Handler returns an HTTP handler for the prometheus.DefaultGatherer. The -// Handler uses the default HandlerOpts, i.e. report the first error as an HTTP -// error, no error logging, and compression if requested by the client. +// Handler returns an http.Handler for the prometheus.DefaultGatherer, using +// default HandlerOpts, i.e. it reports the first error as an HTTP error, it has +// no error logging, and it applies compression if requested by the client. // -// If you want to create a Handler for the DefaultGatherer with different -// HandlerOpts, create it with HandlerFor with prometheus.DefaultGatherer and -// your desired HandlerOpts. +// The returned http.Handler is already instrumented using the +// InstrumentMetricHandler function and the prometheus.DefaultRegisterer. If you +// create multiple http.Handlers by separate calls of the Handler function, the +// metrics used for instrumentation will be shared between them, providing +// global scrape counts. +// +// This function is meant to cover the bulk of basic use cases. If you are doing +// anything that requires more customization (including using a non-default +// Gatherer, different instrumentation, and non-default HandlerOpts), use the +// HandlerFor function. See there for details. func Handler() http.Handler { - return HandlerFor(prometheus.DefaultGatherer, HandlerOpts{}) + return InstrumentMetricHandler( + prometheus.DefaultRegisterer, HandlerFor(prometheus.DefaultGatherer, HandlerOpts{}), + ) } -// HandlerFor returns an http.Handler for the provided Gatherer. The behavior -// of the Handler is defined by the provided HandlerOpts. +// HandlerFor returns an uninstrumented http.Handler for the provided +// Gatherer. The behavior of the Handler is defined by the provided +// HandlerOpts. Thus, HandlerFor is useful to create http.Handlers for custom +// Gatherers, with non-default HandlerOpts, and/or with custom (or no) +// instrumentation. Use the InstrumentMetricHandler function to apply the same +// kind of instrumentation as it is used by the Handler function. func HandlerFor(reg prometheus.Gatherer, opts HandlerOpts) http.Handler { - return http.HandlerFunc(func(w http.ResponseWriter, req *http.Request) { + var inFlightSem chan struct{} + if opts.MaxRequestsInFlight > 0 { + inFlightSem = make(chan struct{}, opts.MaxRequestsInFlight) + } + + h := http.HandlerFunc(func(w http.ResponseWriter, req *http.Request) { + if inFlightSem != nil { + select { + case inFlightSem <- struct{}{}: // All good, carry on. + defer func() { <-inFlightSem }() + default: + http.Error(w, fmt.Sprintf( + "Limit of concurrent requests reached (%d), try again later.", opts.MaxRequestsInFlight, + ), http.StatusServiceUnavailable) + return + } + } + mfs, err := reg.Gather() if err != nil { if opts.ErrorLog != nil { @@ -137,9 +168,70 @@ func HandlerFor(reg prometheus.Gatherer, opts HandlerOpts) http.Handler { if encoding != "" { header.Set(contentEncodingHeader, encoding) } - w.Write(buf.Bytes()) + if _, err := w.Write(buf.Bytes()); err != nil && opts.ErrorLog != nil { + opts.ErrorLog.Println("error while sending encoded metrics:", err) + } // TODO(beorn7): Consider streaming serving of metrics. }) + + if opts.Timeout <= 0 { + return h + } + return http.TimeoutHandler(h, opts.Timeout, fmt.Sprintf( + "Exceeded configured timeout of %v.\n", + opts.Timeout, + )) +} + +// InstrumentMetricHandler is usually used with an http.Handler returned by the +// HandlerFor function. It instruments the provided http.Handler with two +// metrics: A counter vector "promhttp_metric_handler_requests_total" to count +// scrapes partitioned by HTTP status code, and a gauge +// "promhttp_metric_handler_requests_in_flight" to track the number of +// simultaneous scrapes. This function idempotently registers collectors for +// both metrics with the provided Registerer. It panics if the registration +// fails. The provided metrics are useful to see how many scrapes hit the +// monitored target (which could be from different Prometheus servers or other +// scrapers), and how often they overlap (which would result in more than one +// scrape in flight at the same time). Note that the scrapes-in-flight gauge +// will contain the scrape by which it is exposed, while the scrape counter will +// only get incremented after the scrape is complete (as only then the status +// code is known). For tracking scrape durations, use the +// "scrape_duration_seconds" gauge created by the Prometheus server upon each +// scrape. +func InstrumentMetricHandler(reg prometheus.Registerer, handler http.Handler) http.Handler { + cnt := prometheus.NewCounterVec( + prometheus.CounterOpts{ + Name: "promhttp_metric_handler_requests_total", + Help: "Total number of scrapes by HTTP status code.", + }, + []string{"code"}, + ) + // Initialize the most likely HTTP status codes. + cnt.WithLabelValues("200") + cnt.WithLabelValues("500") + cnt.WithLabelValues("503") + if err := reg.Register(cnt); err != nil { + if are, ok := err.(prometheus.AlreadyRegisteredError); ok { + cnt = are.ExistingCollector.(*prometheus.CounterVec) + } else { + panic(err) + } + } + + gge := prometheus.NewGauge(prometheus.GaugeOpts{ + Name: "promhttp_metric_handler_requests_in_flight", + Help: "Current number of scrapes being served.", + }) + if err := reg.Register(gge); err != nil { + if are, ok := err.(prometheus.AlreadyRegisteredError); ok { + gge = are.ExistingCollector.(prometheus.Gauge) + } else { + panic(err) + } + } + + return InstrumentHandlerCounter(cnt, InstrumentHandlerInFlight(gge, handler)) } // HandlerErrorHandling defines how a Handler serving metrics will handle @@ -183,6 +275,21 @@ type HandlerOpts struct { // If DisableCompression is true, the handler will never compress the // response, even if requested by the client. DisableCompression bool + // The number of concurrent HTTP requests is limited to + // MaxRequestsInFlight. Additional requests are responded to with 503 + // Service Unavailable and a suitable message in the body. If + // MaxRequestsInFlight is 0 or negative, no limit is applied. + MaxRequestsInFlight int + // If handling a request takes longer than Timeout, it is responded to + // with 503 ServiceUnavailable and a suitable Message. No timeout is + // applied if Timeout is 0 or negative. Note that with the current + // implementation, reaching the timeout simply ends the HTTP requests as + // described above (and even that only if sending of the body hasn't + // started yet), while the bulk work of gathering all the metrics keeps + // running in the background (with the eventual result to be thrown + // away). Until the implementation is improved, it is recommended to + // implement a separate timeout in potentially slow Collectors. + Timeout time.Duration } // decorateWriter wraps a writer to handle gzip compression if requested. It @@ -195,7 +302,7 @@ func decorateWriter(request *http.Request, writer io.Writer, compressionDisabled header := request.Header.Get(acceptEncodingHeader) parts := strings.Split(header, ",") for _, part := range parts { - part := strings.TrimSpace(part) + part = strings.TrimSpace(part) if part == "gzip" || strings.HasPrefix(part, "gzip;") { return gzip.NewWriter(writer), "gzip" } diff --git a/vendor/github.com/prometheus/client_golang/prometheus/promhttp/instrument_client.go b/vendor/github.com/prometheus/client_golang/prometheus/promhttp/instrument_client.go index 65f9425..86fd564 100644 --- a/vendor/github.com/prometheus/client_golang/prometheus/promhttp/instrument_client.go +++ b/vendor/github.com/prometheus/client_golang/prometheus/promhttp/instrument_client.go @@ -45,12 +45,11 @@ func InstrumentRoundTripperInFlight(gauge prometheus.Gauge, next http.RoundTripp // InstrumentRoundTripperCounter is a middleware that wraps the provided // http.RoundTripper to observe the request result with the provided CounterVec. -// The CounterVec must have zero, one, or two labels. The only allowed label -// names are "code" and "method". The function panics if any other instance -// labels are provided. Partitioning of the CounterVec happens by HTTP status -// code and/or HTTP method if the respective instance label names are present -// in the CounterVec. For unpartitioned counting, use a CounterVec with -// zero labels. +// The CounterVec must have zero, one, or two non-const non-curried labels. For +// those, the only allowed label names are "code" and "method". The function +// panics otherwise. Partitioning of the CounterVec happens by HTTP status code +// and/or HTTP method if the respective instance label names are present in the +// CounterVec. For unpartitioned counting, use a CounterVec with zero labels. // // If the wrapped RoundTripper panics or returns a non-nil error, the Counter // is not incremented. @@ -69,15 +68,15 @@ func InstrumentRoundTripperCounter(counter *prometheus.CounterVec, next http.Rou } // InstrumentRoundTripperDuration is a middleware that wraps the provided -// http.RoundTripper to observe the request duration with the provided ObserverVec. -// The ObserverVec must have zero, one, or two labels. The only allowed label -// names are "code" and "method". The function panics if any other instance -// labels are provided. The Observe method of the Observer in the ObserverVec -// is called with the request duration in seconds. Partitioning happens by HTTP -// status code and/or HTTP method if the respective instance label names are -// present in the ObserverVec. For unpartitioned observations, use an -// ObserverVec with zero labels. Note that partitioning of Histograms is -// expensive and should be used judiciously. +// http.RoundTripper to observe the request duration with the provided +// ObserverVec. The ObserverVec must have zero, one, or two non-const +// non-curried labels. For those, the only allowed label names are "code" and +// "method". The function panics otherwise. The Observe method of the Observer +// in the ObserverVec is called with the request duration in +// seconds. Partitioning happens by HTTP status code and/or HTTP method if the +// respective instance label names are present in the ObserverVec. For +// unpartitioned observations, use an ObserverVec with zero labels. Note that +// partitioning of Histograms is expensive and should be used judiciously. // // If the wrapped RoundTripper panics or returns a non-nil error, no values are // reported. diff --git a/vendor/github.com/prometheus/client_golang/prometheus/promhttp/instrument_client_1_8.go b/vendor/github.com/prometheus/client_golang/prometheus/promhttp/instrument_client_1_8.go index 0bd80c3..a034d1e 100644 --- a/vendor/github.com/prometheus/client_golang/prometheus/promhttp/instrument_client_1_8.go +++ b/vendor/github.com/prometheus/client_golang/prometheus/promhttp/instrument_client_1_8.go @@ -81,8 +81,8 @@ func InstrumentRoundTripperTrace(it *InstrumentTrace, next http.RoundTripper) Ro } }, DNSDone: func(_ httptrace.DNSDoneInfo) { - if it.DNSStart != nil { - it.DNSStart(time.Since(start).Seconds()) + if it.DNSDone != nil { + it.DNSDone(time.Since(start).Seconds()) } }, ConnectStart: func(_, _ string) { diff --git a/vendor/github.com/prometheus/client_golang/prometheus/promhttp/instrument_server.go b/vendor/github.com/prometheus/client_golang/prometheus/promhttp/instrument_server.go index 3d145ad..9db2438 100644 --- a/vendor/github.com/prometheus/client_golang/prometheus/promhttp/instrument_server.go +++ b/vendor/github.com/prometheus/client_golang/prometheus/promhttp/instrument_server.go @@ -14,6 +14,7 @@ package promhttp import ( + "errors" "net/http" "strconv" "strings" @@ -42,10 +43,10 @@ func InstrumentHandlerInFlight(g prometheus.Gauge, next http.Handler) http.Handl // InstrumentHandlerDuration is a middleware that wraps the provided // http.Handler to observe the request duration with the provided ObserverVec. -// The ObserverVec must have zero, one, or two labels. The only allowed label -// names are "code" and "method". The function panics if any other instance -// labels are provided. The Observe method of the Observer in the ObserverVec -// is called with the request duration in seconds. Partitioning happens by HTTP +// The ObserverVec must have zero, one, or two non-const non-curried labels. For +// those, the only allowed label names are "code" and "method". The function +// panics otherwise. The Observe method of the Observer in the ObserverVec is +// called with the request duration in seconds. Partitioning happens by HTTP // status code and/or HTTP method if the respective instance label names are // present in the ObserverVec. For unpartitioned observations, use an // ObserverVec with zero labels. Note that partitioning of Histograms is @@ -77,14 +78,13 @@ func InstrumentHandlerDuration(obs prometheus.ObserverVec, next http.Handler) ht }) } -// InstrumentHandlerCounter is a middleware that wraps the provided -// http.Handler to observe the request result with the provided CounterVec. -// The CounterVec must have zero, one, or two labels. The only allowed label -// names are "code" and "method". The function panics if any other instance -// labels are provided. Partitioning of the CounterVec happens by HTTP status -// code and/or HTTP method if the respective instance label names are present -// in the CounterVec. For unpartitioned counting, use a CounterVec with -// zero labels. +// InstrumentHandlerCounter is a middleware that wraps the provided http.Handler +// to observe the request result with the provided CounterVec. The CounterVec +// must have zero, one, or two non-const non-curried labels. For those, the only +// allowed label names are "code" and "method". The function panics +// otherwise. Partitioning of the CounterVec happens by HTTP status code and/or +// HTTP method if the respective instance label names are present in the +// CounterVec. For unpartitioned counting, use a CounterVec with zero labels. // // If the wrapped Handler does not set a status code, a status code of 200 is assumed. // @@ -111,14 +111,13 @@ func InstrumentHandlerCounter(counter *prometheus.CounterVec, next http.Handler) // InstrumentHandlerTimeToWriteHeader is a middleware that wraps the provided // http.Handler to observe with the provided ObserverVec the request duration // until the response headers are written. The ObserverVec must have zero, one, -// or two labels. The only allowed label names are "code" and "method". The -// function panics if any other instance labels are provided. The Observe -// method of the Observer in the ObserverVec is called with the request -// duration in seconds. Partitioning happens by HTTP status code and/or HTTP -// method if the respective instance label names are present in the -// ObserverVec. For unpartitioned observations, use an ObserverVec with zero -// labels. Note that partitioning of Histograms is expensive and should be used -// judiciously. +// or two non-const non-curried labels. For those, the only allowed label names +// are "code" and "method". The function panics otherwise. The Observe method of +// the Observer in the ObserverVec is called with the request duration in +// seconds. Partitioning happens by HTTP status code and/or HTTP method if the +// respective instance label names are present in the ObserverVec. For +// unpartitioned observations, use an ObserverVec with zero labels. Note that +// partitioning of Histograms is expensive and should be used judiciously. // // If the wrapped Handler panics before calling WriteHeader, no value is // reported. @@ -140,15 +139,15 @@ func InstrumentHandlerTimeToWriteHeader(obs prometheus.ObserverVec, next http.Ha } // InstrumentHandlerRequestSize is a middleware that wraps the provided -// http.Handler to observe the request size with the provided ObserverVec. -// The ObserverVec must have zero, one, or two labels. The only allowed label -// names are "code" and "method". The function panics if any other instance -// labels are provided. The Observe method of the Observer in the ObserverVec -// is called with the request size in bytes. Partitioning happens by HTTP -// status code and/or HTTP method if the respective instance label names are -// present in the ObserverVec. For unpartitioned observations, use an -// ObserverVec with zero labels. Note that partitioning of Histograms is -// expensive and should be used judiciously. +// http.Handler to observe the request size with the provided ObserverVec. The +// ObserverVec must have zero, one, or two non-const non-curried labels. For +// those, the only allowed label names are "code" and "method". The function +// panics otherwise. The Observe method of the Observer in the ObserverVec is +// called with the request size in bytes. Partitioning happens by HTTP status +// code and/or HTTP method if the respective instance label names are present in +// the ObserverVec. For unpartitioned observations, use an ObserverVec with zero +// labels. Note that partitioning of Histograms is expensive and should be used +// judiciously. // // If the wrapped Handler does not set a status code, a status code of 200 is assumed. // @@ -175,15 +174,15 @@ func InstrumentHandlerRequestSize(obs prometheus.ObserverVec, next http.Handler) } // InstrumentHandlerResponseSize is a middleware that wraps the provided -// http.Handler to observe the response size with the provided ObserverVec. -// The ObserverVec must have zero, one, or two labels. The only allowed label -// names are "code" and "method". The function panics if any other instance -// labels are provided. The Observe method of the Observer in the ObserverVec -// is called with the response size in bytes. Partitioning happens by HTTP -// status code and/or HTTP method if the respective instance label names are -// present in the ObserverVec. For unpartitioned observations, use an -// ObserverVec with zero labels. Note that partitioning of Histograms is -// expensive and should be used judiciously. +// http.Handler to observe the response size with the provided ObserverVec. The +// ObserverVec must have zero, one, or two non-const non-curried labels. For +// those, the only allowed label names are "code" and "method". The function +// panics otherwise. The Observe method of the Observer in the ObserverVec is +// called with the response size in bytes. Partitioning happens by HTTP status +// code and/or HTTP method if the respective instance label names are present in +// the ObserverVec. For unpartitioned observations, use an ObserverVec with zero +// labels. Note that partitioning of Histograms is expensive and should be used +// judiciously. // // If the wrapped Handler does not set a status code, a status code of 200 is assumed. // @@ -204,9 +203,12 @@ func checkLabels(c prometheus.Collector) (code bool, method bool) { // once Descriptors can have their dimensionality queried. var ( desc *prometheus.Desc + m prometheus.Metric pm dto.Metric + lvs []string ) + // Get the Desc from the Collector. descc := make(chan *prometheus.Desc, 1) c.Describe(descc) @@ -223,49 +225,54 @@ func checkLabels(c prometheus.Collector) (code bool, method bool) { close(descc) - if _, err := prometheus.NewConstMetric(desc, prometheus.UntypedValue, 0); err == nil { - return + // Create a ConstMetric with the Desc. Since we don't know how many + // variable labels there are, try for as long as it needs. + for err := errors.New("dummy"); err != nil; lvs = append(lvs, magicString) { + m, err = prometheus.NewConstMetric(desc, prometheus.UntypedValue, 0, lvs...) + } + + // Write out the metric into a proto message and look at the labels. + // If the value is not the magicString, it is a constLabel, which doesn't interest us. + // If the label is curried, it doesn't interest us. + // In all other cases, only "code" or "method" is allowed. + if err := m.Write(&pm); err != nil { + panic("error checking metric for labels") } - if m, err := prometheus.NewConstMetric(desc, prometheus.UntypedValue, 0, magicString); err == nil { - if err := m.Write(&pm); err != nil { - panic("error checking metric for labels") + for _, label := range pm.Label { + name, value := label.GetName(), label.GetValue() + if value != magicString || isLabelCurried(c, name) { + continue } - for _, label := range pm.Label { - name, value := label.GetName(), label.GetValue() - if value != magicString { - continue - } - switch name { - case "code": - code = true - case "method": - method = true - default: - panic("metric partitioned with non-supported labels") - } - return + switch name { + case "code": + code = true + case "method": + method = true + default: + panic("metric partitioned with non-supported labels") } - panic("previously set label not found – this must never happen") } - if m, err := prometheus.NewConstMetric(desc, prometheus.UntypedValue, 0, magicString, magicString); err == nil { - if err := m.Write(&pm); err != nil { - panic("error checking metric for labels") + return +} + +func isLabelCurried(c prometheus.Collector, label string) bool { + // This is even hackier than the label test above. + // We essentially try to curry again and see if it works. + // But for that, we need to type-convert to the two + // types we use here, ObserverVec or *CounterVec. + switch v := c.(type) { + case *prometheus.CounterVec: + if _, err := v.CurryWith(prometheus.Labels{label: "dummy"}); err == nil { + return false } - for _, label := range pm.Label { - name, value := label.GetName(), label.GetValue() - if value != magicString { - continue - } - if name == "code" || name == "method" { - continue - } - panic("metric partitioned with non-supported labels") + case prometheus.ObserverVec: + if _, err := v.CurryWith(prometheus.Labels{label: "dummy"}); err == nil { + return false } - code = true - method = true - return + default: + panic("unsupported metric vec type") } - panic("metric partitioned with non-supported labels") + return true } // emptyLabels is a one-time allocation for non-partitioned metrics to avoid diff --git a/vendor/github.com/prometheus/client_golang/prometheus/registry.go b/vendor/github.com/prometheus/client_golang/prometheus/registry.go index c84a442..fdb7bad 100644 --- a/vendor/github.com/prometheus/client_golang/prometheus/registry.go +++ b/vendor/github.com/prometheus/client_golang/prometheus/registry.go @@ -18,6 +18,7 @@ import ( "errors" "fmt" "os" + "runtime" "sort" "sync" "unicode/utf8" @@ -36,13 +37,14 @@ const ( // DefaultRegisterer and DefaultGatherer are the implementations of the // Registerer and Gatherer interface a number of convenience functions in this // package act on. Initially, both variables point to the same Registry, which -// has a process collector (see NewProcessCollector) and a Go collector (see -// NewGoCollector) already registered. This approach to keep default instances -// as global state mirrors the approach of other packages in the Go standard -// library. Note that there are caveats. Change the variables with caution and -// only if you understand the consequences. Users who want to avoid global state -// altogether should not use the convenience function and act on custom -// instances instead. +// has a process collector (currently on Linux only, see NewProcessCollector) +// and a Go collector (see NewGoCollector, in particular the note about +// stop-the-world implication with Go versions older than 1.9) already +// registered. This approach to keep default instances as global state mirrors +// the approach of other packages in the Go standard library. Note that there +// are caveats. Change the variables with caution and only if you understand the +// consequences. Users who want to avoid global state altogether should not use +// the convenience functions and act on custom instances instead. var ( defaultRegistry = NewRegistry() DefaultRegisterer Registerer = defaultRegistry @@ -124,15 +126,23 @@ type Registerer interface { type Gatherer interface { // Gather calls the Collect method of the registered Collectors and then // gathers the collected metrics into a lexicographically sorted slice - // of MetricFamily protobufs. Even if an error occurs, Gather attempts - // to gather as many metrics as possible. Hence, if a non-nil error is - // returned, the returned MetricFamily slice could be nil (in case of a - // fatal error that prevented any meaningful metric collection) or - // contain a number of MetricFamily protobufs, some of which might be - // incomplete, and some might be missing altogether. The returned error - // (which might be a MultiError) explains the details. In scenarios - // where complete collection is critical, the returned MetricFamily - // protobufs should be disregarded if the returned error is non-nil. + // of uniquely named MetricFamily protobufs. Gather ensures that the + // returned slice is valid and self-consistent so that it can be used + // for valid exposition. As an exception to the strict consistency + // requirements described for metric.Desc, Gather will tolerate + // different sets of label names for metrics of the same metric family. + // + // Even if an error occurs, Gather attempts to gather as many metrics as + // possible. Hence, if a non-nil error is returned, the returned + // MetricFamily slice could be nil (in case of a fatal error that + // prevented any meaningful metric collection) or contain a number of + // MetricFamily protobufs, some of which might be incomplete, and some + // might be missing altogether. The returned error (which might be a + // MultiError) explains the details. Note that this is mostly useful for + // debugging purposes. If the gathered protobufs are to be used for + // exposition in actual monitoring, it is almost always better to not + // expose an incomplete result and instead disregard the returned + // MetricFamily protobufs in case the returned error is non-nil. Gather() ([]*dto.MetricFamily, error) } @@ -202,6 +212,13 @@ func (errs MultiError) Error() string { return buf.String() } +// Append appends the provided error if it is not nil. +func (errs *MultiError) Append(err error) { + if err != nil { + *errs = append(*errs, err) + } +} + // MaybeUnwrap returns nil if len(errs) is 0. It returns the first and only // contained error as error if len(errs is 1). In all other cases, it returns // the MultiError directly. This is helpful for returning a MultiError in a way @@ -361,29 +378,18 @@ func (r *Registry) Gather() ([]*dto.MetricFamily, error) { var ( metricChan = make(chan Metric, capMetricChan) metricHashes = map[uint64]struct{}{} - dimHashes = map[string]uint64{} wg sync.WaitGroup errs MultiError // The collected errors to return in the end. registeredDescIDs map[uint64]struct{} // Only used for pedantic checks ) r.mtx.RLock() + goroutineBudget := len(r.collectorsByID) metricFamiliesByName := make(map[string]*dto.MetricFamily, len(r.dimHashesByName)) - - // Scatter. - // (Collectors could be complex and slow, so we call them all at once.) - wg.Add(len(r.collectorsByID)) - go func() { - wg.Wait() - close(metricChan) - }() + collectors := make(chan Collector, len(r.collectorsByID)) for _, collector := range r.collectorsByID { - go func(collector Collector) { - defer wg.Done() - collector.Collect(metricChan) - }(collector) + collectors <- collector } - // In case pedantic checks are enabled, we have to copy the map before // giving up the RLock. if r.pedanticChecksEnabled { @@ -392,127 +398,173 @@ func (r *Registry) Gather() ([]*dto.MetricFamily, error) { registeredDescIDs[id] = struct{}{} } } - r.mtx.RUnlock() + wg.Add(goroutineBudget) + + collectWorker := func() { + for { + select { + case collector := <-collectors: + collector.Collect(metricChan) + wg.Done() + default: + return + } + } + } + + // Start the first worker now to make sure at least one is running. + go collectWorker() + goroutineBudget-- + + // Close the metricChan once all collectors are collected. + go func() { + wg.Wait() + close(metricChan) + }() + // Drain metricChan in case of premature return. defer func() { for range metricChan { } }() - // Gather. - for metric := range metricChan { - // This could be done concurrently, too, but it required locking - // of metricFamiliesByName (and of metricHashes if checks are - // enabled). Most likely not worth it. - desc := metric.Desc() - dtoMetric := &dto.Metric{} - if err := metric.Write(dtoMetric); err != nil { - errs = append(errs, fmt.Errorf( - "error collecting metric %v: %s", desc, err, - )) - continue - } - metricFamily, ok := metricFamiliesByName[desc.fqName] - if ok { - if metricFamily.GetHelp() != desc.help { - errs = append(errs, fmt.Errorf( - "collected metric %s %s has help %q but should have %q", - desc.fqName, dtoMetric, desc.help, metricFamily.GetHelp(), - )) - continue +collectLoop: + for { + select { + case metric, ok := <-metricChan: + if !ok { + // metricChan is closed, we are done. + break collectLoop } - // TODO(beorn7): Simplify switch once Desc has type. - switch metricFamily.GetType() { - case dto.MetricType_COUNTER: - if dtoMetric.Counter == nil { - errs = append(errs, fmt.Errorf( - "collected metric %s %s should be a Counter", - desc.fqName, dtoMetric, - )) - continue - } - case dto.MetricType_GAUGE: - if dtoMetric.Gauge == nil { - errs = append(errs, fmt.Errorf( - "collected metric %s %s should be a Gauge", - desc.fqName, dtoMetric, - )) - continue - } - case dto.MetricType_SUMMARY: - if dtoMetric.Summary == nil { - errs = append(errs, fmt.Errorf( - "collected metric %s %s should be a Summary", - desc.fqName, dtoMetric, - )) - continue - } - case dto.MetricType_UNTYPED: - if dtoMetric.Untyped == nil { - errs = append(errs, fmt.Errorf( - "collected metric %s %s should be Untyped", - desc.fqName, dtoMetric, - )) - continue - } - case dto.MetricType_HISTOGRAM: - if dtoMetric.Histogram == nil { - errs = append(errs, fmt.Errorf( - "collected metric %s %s should be a Histogram", - desc.fqName, dtoMetric, + errs.Append(processMetric( + metric, metricFamiliesByName, + metricHashes, + registeredDescIDs, + )) + default: + if goroutineBudget <= 0 || len(collectors) == 0 { + // All collectors are already being worked on or + // we have already as many goroutines started as + // there are collectors. Just process metrics + // from now on. + for metric := range metricChan { + errs.Append(processMetric( + metric, metricFamiliesByName, + metricHashes, + registeredDescIDs, )) - continue } - default: - panic("encountered MetricFamily with invalid type") - } - } else { - metricFamily = &dto.MetricFamily{} - metricFamily.Name = proto.String(desc.fqName) - metricFamily.Help = proto.String(desc.help) - // TODO(beorn7): Simplify switch once Desc has type. - switch { - case dtoMetric.Gauge != nil: - metricFamily.Type = dto.MetricType_GAUGE.Enum() - case dtoMetric.Counter != nil: - metricFamily.Type = dto.MetricType_COUNTER.Enum() - case dtoMetric.Summary != nil: - metricFamily.Type = dto.MetricType_SUMMARY.Enum() - case dtoMetric.Untyped != nil: - metricFamily.Type = dto.MetricType_UNTYPED.Enum() - case dtoMetric.Histogram != nil: - metricFamily.Type = dto.MetricType_HISTOGRAM.Enum() - default: - errs = append(errs, fmt.Errorf( - "empty metric collected: %s", dtoMetric, - )) - continue + break collectLoop } - metricFamiliesByName[desc.fqName] = metricFamily + // Start more workers. + go collectWorker() + goroutineBudget-- + runtime.Gosched() } - if err := checkMetricConsistency(metricFamily, dtoMetric, metricHashes, dimHashes); err != nil { - errs = append(errs, err) - continue + } + return normalizeMetricFamilies(metricFamiliesByName), errs.MaybeUnwrap() +} + +// processMetric is an internal helper method only used by the Gather method. +func processMetric( + metric Metric, + metricFamiliesByName map[string]*dto.MetricFamily, + metricHashes map[uint64]struct{}, + registeredDescIDs map[uint64]struct{}, +) error { + desc := metric.Desc() + dtoMetric := &dto.Metric{} + if err := metric.Write(dtoMetric); err != nil { + return fmt.Errorf("error collecting metric %v: %s", desc, err) + } + metricFamily, ok := metricFamiliesByName[desc.fqName] + if ok { + if metricFamily.GetHelp() != desc.help { + return fmt.Errorf( + "collected metric %s %s has help %q but should have %q", + desc.fqName, dtoMetric, desc.help, metricFamily.GetHelp(), + ) } - if r.pedanticChecksEnabled { - // Is the desc registered at all? - if _, exist := registeredDescIDs[desc.id]; !exist { - errs = append(errs, fmt.Errorf( - "collected metric %s %s with unregistered descriptor %s", - metricFamily.GetName(), dtoMetric, desc, - )) - continue + // TODO(beorn7): Simplify switch once Desc has type. + switch metricFamily.GetType() { + case dto.MetricType_COUNTER: + if dtoMetric.Counter == nil { + return fmt.Errorf( + "collected metric %s %s should be a Counter", + desc.fqName, dtoMetric, + ) + } + case dto.MetricType_GAUGE: + if dtoMetric.Gauge == nil { + return fmt.Errorf( + "collected metric %s %s should be a Gauge", + desc.fqName, dtoMetric, + ) } - if err := checkDescConsistency(metricFamily, dtoMetric, desc); err != nil { - errs = append(errs, err) - continue + case dto.MetricType_SUMMARY: + if dtoMetric.Summary == nil { + return fmt.Errorf( + "collected metric %s %s should be a Summary", + desc.fqName, dtoMetric, + ) } + case dto.MetricType_UNTYPED: + if dtoMetric.Untyped == nil { + return fmt.Errorf( + "collected metric %s %s should be Untyped", + desc.fqName, dtoMetric, + ) + } + case dto.MetricType_HISTOGRAM: + if dtoMetric.Histogram == nil { + return fmt.Errorf( + "collected metric %s %s should be a Histogram", + desc.fqName, dtoMetric, + ) + } + default: + panic("encountered MetricFamily with invalid type") } - metricFamily.Metric = append(metricFamily.Metric, dtoMetric) + } else { + metricFamily = &dto.MetricFamily{} + metricFamily.Name = proto.String(desc.fqName) + metricFamily.Help = proto.String(desc.help) + // TODO(beorn7): Simplify switch once Desc has type. + switch { + case dtoMetric.Gauge != nil: + metricFamily.Type = dto.MetricType_GAUGE.Enum() + case dtoMetric.Counter != nil: + metricFamily.Type = dto.MetricType_COUNTER.Enum() + case dtoMetric.Summary != nil: + metricFamily.Type = dto.MetricType_SUMMARY.Enum() + case dtoMetric.Untyped != nil: + metricFamily.Type = dto.MetricType_UNTYPED.Enum() + case dtoMetric.Histogram != nil: + metricFamily.Type = dto.MetricType_HISTOGRAM.Enum() + default: + return fmt.Errorf("empty metric collected: %s", dtoMetric) + } + metricFamiliesByName[desc.fqName] = metricFamily } - return normalizeMetricFamilies(metricFamiliesByName), errs.MaybeUnwrap() + if err := checkMetricConsistency(metricFamily, dtoMetric, metricHashes); err != nil { + return err + } + if registeredDescIDs != nil { + // Is the desc registered at all? + if _, exist := registeredDescIDs[desc.id]; !exist { + return fmt.Errorf( + "collected metric %s %s with unregistered descriptor %s", + metricFamily.GetName(), dtoMetric, desc, + ) + } + if err := checkDescConsistency(metricFamily, dtoMetric, desc); err != nil { + return err + } + } + metricFamily.Metric = append(metricFamily.Metric, dtoMetric) + return nil } // Gatherers is a slice of Gatherer instances that implements the Gatherer @@ -538,7 +590,6 @@ func (gs Gatherers) Gather() ([]*dto.MetricFamily, error) { var ( metricFamiliesByName = map[string]*dto.MetricFamily{} metricHashes = map[uint64]struct{}{} - dimHashes = map[string]uint64{} errs MultiError // The collected errors to return in the end. ) @@ -578,7 +629,7 @@ func (gs Gatherers) Gather() ([]*dto.MetricFamily, error) { metricFamiliesByName[mf.GetName()] = existingMF } for _, m := range mf.Metric { - if err := checkMetricConsistency(existingMF, m, metricHashes, dimHashes); err != nil { + if err := checkMetricConsistency(existingMF, m, metricHashes); err != nil { errs = append(errs, err) continue } @@ -655,18 +706,13 @@ func normalizeMetricFamilies(metricFamiliesByName map[string]*dto.MetricFamily) } // checkMetricConsistency checks if the provided Metric is consistent with the -// provided MetricFamily. It also hashed the Metric labels and the MetricFamily +// provided MetricFamily. It also hashes the Metric labels and the MetricFamily // name. If the resulting hash is already in the provided metricHashes, an error -// is returned. If not, it is added to metricHashes. The provided dimHashes maps -// MetricFamily names to their dimHash (hashed sorted label names). If dimHashes -// doesn't yet contain a hash for the provided MetricFamily, it is -// added. Otherwise, an error is returned if the existing dimHashes in not equal -// the calculated dimHash. +// is returned. If not, it is added to metricHashes. func checkMetricConsistency( metricFamily *dto.MetricFamily, dtoMetric *dto.Metric, metricHashes map[uint64]struct{}, - dimHashes map[string]uint64, ) error { // Type consistency with metric family. if metricFamily.GetType() == dto.MetricType_GAUGE && dtoMetric.Gauge == nil || @@ -681,24 +727,23 @@ func checkMetricConsistency( } for _, labelPair := range dtoMetric.GetLabel() { - if !utf8.ValidString(*labelPair.Value) { - return fmt.Errorf("collected metric's label %s is not utf8: %#v", *labelPair.Name, *labelPair.Value) + if !utf8.ValidString(labelPair.GetValue()) { + return fmt.Errorf("collected metric's label %s is not utf8: %#v", labelPair.GetName(), labelPair.GetValue()) } } - // Is the metric unique (i.e. no other metric with the same name and the same label values)? + // Is the metric unique (i.e. no other metric with the same name and the same labels)? h := hashNew() h = hashAdd(h, metricFamily.GetName()) h = hashAddByte(h, separatorByte) - dh := hashNew() // Make sure label pairs are sorted. We depend on it for the consistency // check. sort.Sort(LabelPairSorter(dtoMetric.Label)) for _, lp := range dtoMetric.Label { + h = hashAdd(h, lp.GetName()) + h = hashAddByte(h, separatorByte) h = hashAdd(h, lp.GetValue()) h = hashAddByte(h, separatorByte) - dh = hashAdd(dh, lp.GetName()) - dh = hashAddByte(dh, separatorByte) } if _, exists := metricHashes[h]; exists { return fmt.Errorf( @@ -706,16 +751,6 @@ func checkMetricConsistency( metricFamily.GetName(), dtoMetric, ) } - if dimHash, ok := dimHashes[metricFamily.GetName()]; ok { - if dimHash != dh { - return fmt.Errorf( - "collected metric %s %s has label dimensions inconsistent with previously collected metrics in the same metric family", - metricFamily.GetName(), dtoMetric, - ) - } - } else { - dimHashes[metricFamily.GetName()] = dh - } metricHashes[h] = struct{}{} return nil } diff --git a/vendor/github.com/prometheus/client_golang/prometheus/summary.go b/vendor/github.com/prometheus/client_golang/prometheus/summary.go index 21c031e..f7dc85b 100644 --- a/vendor/github.com/prometheus/client_golang/prometheus/summary.go +++ b/vendor/github.com/prometheus/client_golang/prometheus/summary.go @@ -101,23 +101,16 @@ type SummaryOpts struct { // string. Help string - // ConstLabels are used to attach fixed labels to this - // Summary. Summaries with the same fully-qualified name must have the - // same label names in their ConstLabels. + // ConstLabels are used to attach fixed labels to this metric. Metrics + // with the same fully-qualified name must have the same label names in + // their ConstLabels. // - // Note that in most cases, labels have a value that varies during the - // lifetime of a process. Those labels are usually managed with a - // SummaryVec. ConstLabels serve only special purposes. One is for the - // special case where the value of a label does not change during the - // lifetime of a process, e.g. if the revision of the running binary is - // put into a label. Another, more advanced purpose is if more than one - // Collector needs to collect Summaries with the same fully-qualified - // name. In that case, those Summaries must differ in the values of - // their ConstLabels. See the Collector examples. - // - // If the value of a label never changes (not even between binaries), - // that label most likely should not be a label at all (but part of the - // metric name). + // ConstLabels are only used rarely. In particular, do not use them to + // attach the same labels to all your metrics. Those use cases are + // better covered by target labels set by the scraping Prometheus + // server, or by one specific metric (e.g. a build_info or a + // machine_role metric). See also + // https://prometheus.io/docs/instrumenting/writing_exporters/#target-labels,-not-static-scraped-labels ConstLabels Labels // Objectives defines the quantile rank estimates with their respective @@ -433,13 +426,13 @@ func NewSummaryVec(opts SummaryOpts, labelNames []string) *SummaryVec { // // Keeping the Summary 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 Summary from the SummaryVec. In that case, the -// Summary will still exist, but it will not be exported anymore, even if a +// Delete can be used to delete the Summary from the SummaryVec. In that case, +// the Summary will still exist, but it will not be exported anymore, even if a // Summary 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. +// 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 @@ -447,8 +440,8 @@ func NewSummaryVec(opts SummaryOpts, labelNames []string) *SummaryVec { // 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 *SummaryVec) GetMetricWithLabelValues(lvs ...string) (Observer, error) { - metric, err := m.metricVec.getMetricWithLabelValues(lvs...) +func (v *SummaryVec) GetMetricWithLabelValues(lvs ...string) (Observer, error) { + metric, err := v.metricVec.getMetricWithLabelValues(lvs...) if metric != nil { return metric.(Observer), err } @@ -462,13 +455,13 @@ func (m *SummaryVec) GetMetricWithLabelValues(lvs ...string) (Observer, error) { // 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. +// 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 (m *SummaryVec) GetMetricWith(labels Labels) (Observer, error) { - metric, err := m.metricVec.getMetricWith(labels) +func (v *SummaryVec) GetMetricWith(labels Labels) (Observer, error) { + metric, err := v.metricVec.getMetricWith(labels) if metric != nil { return metric.(Observer), err } @@ -476,18 +469,57 @@ func (m *SummaryVec) GetMetricWith(labels Labels) (Observer, error) { } // WithLabelValues works as GetMetricWithLabelValues, but panics where -// GetMetricWithLabelValues would have returned an error. By not returning an -// error, WithLabelValues allows shortcuts like +// GetMetricWithLabelValues would have returned an error. Not returning an +// error allows shortcuts like // myVec.WithLabelValues("404", "GET").Observe(42.21) -func (m *SummaryVec) WithLabelValues(lvs ...string) Observer { - return m.metricVec.withLabelValues(lvs...).(Observer) +func (v *SummaryVec) WithLabelValues(lvs ...string) Observer { + s, err := v.GetMetricWithLabelValues(lvs...) + if err != nil { + panic(err) + } + return s } // With works as GetMetricWith, but panics where GetMetricWithLabels would have -// returned an error. By not returning an error, With allows shortcuts like -// myVec.With(Labels{"code": "404", "method": "GET"}).Observe(42.21) -func (m *SummaryVec) With(labels Labels) Observer { - return m.metricVec.with(labels).(Observer) +// returned an error. Not returning an error allows shortcuts like +// myVec.With(prometheus.Labels{"code": "404", "method": "GET"}).Observe(42.21) +func (v *SummaryVec) With(labels Labels) Observer { + s, err := v.GetMetricWith(labels) + if err != nil { + panic(err) + } + return s +} + +// 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 SummaryVec 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 *SummaryVec) CurryWith(labels Labels) (ObserverVec, error) { + vec, err := v.curryWith(labels) + if vec != nil { + return &SummaryVec{vec}, err + } + return nil, err +} + +// MustCurryWith works as CurryWith but panics where CurryWith would have +// returned an error. +func (v *SummaryVec) MustCurryWith(labels Labels) ObserverVec { + vec, err := v.CurryWith(labels) + if err != nil { + panic(err) + } + return vec } type constSummary struct { diff --git a/vendor/github.com/prometheus/client_golang/prometheus/value.go b/vendor/github.com/prometheus/client_golang/prometheus/value.go index 4a9cca6..9fb7eab 100644 --- a/vendor/github.com/prometheus/client_golang/prometheus/value.go +++ b/vendor/github.com/prometheus/client_golang/prometheus/value.go @@ -15,10 +15,7 @@ package prometheus import ( "fmt" - "math" "sort" - "sync/atomic" - "time" dto "github.com/prometheus/client_model/go" @@ -36,79 +33,6 @@ const ( UntypedValue ) -// value is a generic metric for simple values. It implements Metric, Collector, -// Counter, Gauge, and Untyped. Its effective type is determined by -// ValueType. This is a low-level building block used by the library to back the -// implementations of Counter, Gauge, and Untyped. -type value 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 - valType ValueType - labelPairs []*dto.LabelPair -} - -// newValue returns a newly allocated value with the given Desc, ValueType, -// sample value and label values. It panics if the number of label -// values is different from the number of variable labels in Desc. -func newValue(desc *Desc, valueType ValueType, val float64, labelValues ...string) *value { - if len(labelValues) != len(desc.variableLabels) { - panic(errInconsistentCardinality) - } - result := &value{ - desc: desc, - valType: valueType, - valBits: math.Float64bits(val), - labelPairs: makeLabelPairs(desc, labelValues), - } - result.init(result) - return result -} - -func (v *value) Desc() *Desc { - return v.desc -} - -func (v *value) Set(val float64) { - atomic.StoreUint64(&v.valBits, math.Float64bits(val)) -} - -func (v *value) SetToCurrentTime() { - v.Set(float64(time.Now().UnixNano()) / 1e9) -} - -func (v *value) Inc() { - v.Add(1) -} - -func (v *value) Dec() { - v.Add(-1) -} - -func (v *value) Add(val float64) { - for { - oldBits := atomic.LoadUint64(&v.valBits) - newBits := math.Float64bits(math.Float64frombits(oldBits) + val) - if atomic.CompareAndSwapUint64(&v.valBits, oldBits, newBits) { - return - } - } -} - -func (v *value) Sub(val float64) { - v.Add(val * -1) -} - -func (v *value) Write(out *dto.Metric) error { - val := math.Float64frombits(atomic.LoadUint64(&v.valBits)) - return populateMetric(v.valType, val, v.labelPairs, out) -} - // 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 @@ -228,9 +152,7 @@ func makeLabelPairs(desc *Desc, labelValues []string) []*dto.LabelPair { Value: proto.String(labelValues[i]), }) } - for _, lp := range desc.constLabelPairs { - labelPairs = append(labelPairs, lp) - } + labelPairs = append(labelPairs, desc.constLabelPairs...) sort.Sort(LabelPairSorter(labelPairs)) return labelPairs } diff --git a/vendor/github.com/prometheus/client_golang/prometheus/vec.go b/vendor/github.com/prometheus/client_golang/prometheus/vec.go index 65d13fe..14ed9e8 100644 --- a/vendor/github.com/prometheus/client_golang/prometheus/vec.go +++ b/vendor/github.com/prometheus/client_golang/prometheus/vec.go @@ -23,88 +23,31 @@ import ( // 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. +// a given metric type, like GaugeVec, CounterVec, SummaryVec, and HistogramVec. +// It also handles label currying. It uses basicMetricVec internally. type metricVec struct { - mtx sync.RWMutex // Protects the children. - children map[uint64][]metricWithLabelValues - desc *Desc + *metricMap - newMetric func(labelValues ...string) Metric - hashAdd func(h uint64, s string) uint64 // replace hash function for testing collision handling + 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{ - children: map[uint64][]metricWithLabelValues{}, - desc: desc, - newMetric: newMetric, + metricMap: &metricMap{ + metrics: map[uint64][]metricWithLabelValues{}, + desc: desc, + newMetric: newMetric, + }, hashAdd: hashAdd, hashAddByte: hashAddByte, } } -// metricWithLabelValues provides the metric and its label values for -// disambiguation on hash collision. -type metricWithLabelValues struct { - values []string - metric Metric -} - -// Describe implements Collector. The length of the returned slice -// is always one. -func (m *metricVec) Describe(ch chan<- *Desc) { - ch <- m.desc -} - -// Collect implements Collector. -func (m *metricVec) Collect(ch chan<- Metric) { - m.mtx.RLock() - defer m.mtx.RUnlock() - - for _, metrics := range m.children { - for _, metric := range metrics { - ch <- metric.metric - } - } -} - -func (m *metricVec) getMetricWithLabelValues(lvs ...string) (Metric, error) { - h, err := m.hashLabelValues(lvs) - if err != nil { - return nil, err - } - - return m.getOrCreateMetricWithLabelValues(h, lvs), nil -} - -func (m *metricVec) getMetricWith(labels Labels) (Metric, error) { - h, err := m.hashLabels(labels) - if err != nil { - return nil, err - } - - return m.getOrCreateMetricWithLabels(h, labels), nil -} - -func (m *metricVec) withLabelValues(lvs ...string) Metric { - metric, err := m.getMetricWithLabelValues(lvs...) - if err != nil { - panic(err) - } - return metric -} - -func (m *metricVec) with(labels Labels) Metric { - metric, err := m.getMetricWith(labels) - if err != nil { - panic(err) - } - return metric -} - // 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. @@ -121,14 +64,12 @@ func (m *metricVec) with(labels Labels) Metric { // with a performance overhead (for creating and processing the Labels map). // See also the CounterVec example. func (m *metricVec) DeleteLabelValues(lvs ...string) bool { - m.mtx.Lock() - defer m.mtx.Unlock() - h, err := m.hashLabelValues(lvs) if err != nil { return false } - return m.deleteByHashWithLabelValues(h, lvs) + + return m.metricMap.deleteByHashWithLabelValues(h, lvs, m.curry) } // Delete deletes the metric where the variable labels are the same as those @@ -142,35 +83,190 @@ func (m *metricVec) DeleteLabelValues(lvs ...string) bool { // 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 { - m.mtx.Lock() - defer m.mtx.Unlock() - h, err := m.hashLabels(labels) if err != nil { return false } - return m.deleteByHashWithLabels(h, labels) + 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 *metricVec) deleteByHashWithLabelValues(h uint64, lvs []string) bool { - metrics, ok := m.children[h] +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 := m.findMetricWithLabelValues(metrics, lvs) + i := findMetricWithLabelValues(metrics, lvs, curry) if i >= len(metrics) { return false } if len(metrics) > 1 { - m.children[h] = append(metrics[:i], metrics[i+1:]...) + m.metrics[h] = append(metrics[:i], metrics[i+1:]...) } else { - delete(m.children, h) + delete(m.metrics, h) } return true } @@ -178,71 +274,38 @@ 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 { - metrics, ok := m.children[h] +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 := m.findMetricWithLabels(metrics, labels) + i := findMetricWithLabels(m.desc, metrics, labels, curry) if i >= len(metrics) { return false } if len(metrics) > 1 { - m.children[h] = append(metrics[:i], metrics[i+1:]...) + m.metrics[h] = append(metrics[:i], metrics[i+1:]...) } else { - delete(m.children, h) + delete(m.metrics, h) } return true } -// Reset deletes all metrics in this vector. -func (m *metricVec) Reset() { - m.mtx.Lock() - defer m.mtx.Unlock() - - for h := range m.children { - delete(m.children, h) - } -} - -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) - 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)); err != nil { - return 0, err - } - - h := hashNew() - for _, label := range m.desc.variableLabels { - val, ok := labels[label] - 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 -} - // getOrCreateMetricWithLabelValues retrieves the metric by hash and label value // or creates it and returns the new one. // // This function holds the mutex. -func (m *metricVec) getOrCreateMetricWithLabelValues(hash uint64, lvs []string) Metric { +func (m *metricMap) getOrCreateMetricWithLabelValues( + hash uint64, lvs []string, curry []curriedLabelValue, +) Metric { m.mtx.RLock() - metric, ok := m.getMetricWithHashAndLabelValues(hash, lvs) + metric, ok := m.getMetricWithHashAndLabelValues(hash, lvs, curry) m.mtx.RUnlock() if ok { return metric @@ -250,13 +313,11 @@ func (m *metricVec) getOrCreateMetricWithLabelValues(hash uint64, lvs []string) m.mtx.Lock() defer m.mtx.Unlock() - metric, ok = m.getMetricWithHashAndLabelValues(hash, lvs) + metric, ok = m.getMetricWithHashAndLabelValues(hash, lvs, curry) if !ok { - // Copy to avoid allocation in case wo don't go down this code path. - copiedLVs := make([]string, len(lvs)) - copy(copiedLVs, lvs) - metric = m.newMetric(copiedLVs...) - m.children[hash] = append(m.children[hash], metricWithLabelValues{values: copiedLVs, metric: metric}) + inlinedLVs := inlineLabelValues(lvs, curry) + metric = m.newMetric(inlinedLVs...) + m.metrics[hash] = append(m.metrics[hash], metricWithLabelValues{values: inlinedLVs, metric: metric}) } return metric } @@ -265,9 +326,11 @@ 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 *metricMap) getOrCreateMetricWithLabels( + hash uint64, labels Labels, curry []curriedLabelValue, +) Metric { m.mtx.RLock() - metric, ok := m.getMetricWithHashAndLabels(hash, labels) + metric, ok := m.getMetricWithHashAndLabels(hash, labels, curry) m.mtx.RUnlock() if ok { return metric @@ -275,21 +338,23 @@ func (m *metricVec) getOrCreateMetricWithLabels(hash uint64, labels Labels) Metr m.mtx.Lock() defer m.mtx.Unlock() - metric, ok = m.getMetricWithHashAndLabels(hash, labels) + metric, ok = m.getMetricWithHashAndLabels(hash, labels, curry) if !ok { - lvs := m.extractLabelValues(labels) + lvs := extractLabelValues(m.desc, labels, curry) metric = m.newMetric(lvs...) - m.children[hash] = append(m.children[hash], metricWithLabelValues{values: lvs, metric: metric}) + 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 *metricVec) getMetricWithHashAndLabelValues(h uint64, lvs []string) (Metric, bool) { - metrics, ok := m.children[h] +func (m *metricMap) getMetricWithHashAndLabelValues( + h uint64, lvs []string, curry []curriedLabelValue, +) (Metric, bool) { + metrics, ok := m.metrics[h] if ok { - if i := m.findMetricWithLabelValues(metrics, lvs); i < len(metrics) { + if i := findMetricWithLabelValues(metrics, lvs, curry); i < len(metrics) { return metrics[i].metric, true } } @@ -298,10 +363,12 @@ func (m *metricVec) getMetricWithHashAndLabelValues(h uint64, lvs []string) (Met // getMetricWithHashAndLabels gets a metric while handling possible collisions in // the hash space. Must be called while holding read mutex. -func (m *metricVec) getMetricWithHashAndLabels(h uint64, labels Labels) (Metric, bool) { - metrics, ok := m.children[h] +func (m *metricMap) getMetricWithHashAndLabels( + h uint64, labels Labels, curry []curriedLabelValue, +) (Metric, bool) { + metrics, ok := m.metrics[h] if ok { - if i := m.findMetricWithLabels(metrics, labels); i < len(metrics) { + if i := findMetricWithLabels(m.desc, metrics, labels, curry); i < len(metrics) { return metrics[i].metric, true } } @@ -310,9 +377,11 @@ func (m *metricVec) getMetricWithHashAndLabels(h uint64, labels Labels) (Metric, // findMetricWithLabelValues returns the index of the matching metric or // len(metrics) if not found. -func (m *metricVec) findMetricWithLabelValues(metrics []metricWithLabelValues, lvs []string) int { +func findMetricWithLabelValues( + metrics []metricWithLabelValues, lvs []string, curry []curriedLabelValue, +) int { for i, metric := range metrics { - if m.matchLabelValues(metric.values, lvs) { + if matchLabelValues(metric.values, lvs, curry) { return i } } @@ -321,32 +390,51 @@ 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 findMetricWithLabels( + desc *Desc, metrics []metricWithLabelValues, labels Labels, curry []curriedLabelValue, +) int { for i, metric := range metrics { - if m.matchLabels(metric.values, labels) { + if matchLabels(desc, metric.values, labels, curry) { return i } } return len(metrics) } -func (m *metricVec) matchLabelValues(values []string, lvs []string) bool { - if len(values) != len(lvs) { +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 v != lvs[i] { + 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 (m *metricVec) matchLabels(values []string, labels Labels) bool { - if len(labels) != len(values) { +func matchLabels(desc *Desc, values []string, labels Labels, curry []curriedLabelValue) bool { + if len(values) != len(labels)+len(curry) { return false } - for i, k := range m.desc.variableLabels { + 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 } @@ -354,10 +442,31 @@ func (m *metricVec) matchLabels(values []string, labels Labels) bool { return true } -func (m *metricVec) extractLabelValues(labels Labels) []string { - labelValues := make([]string, len(labels)) - for i, k := range m.desc.variableLabels { +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 +} |