vendor: upgrade "github.com/prometheus/client_golang"

Signed-off-by: Gyuho Lee <gyuhox@gmail.com>

Gopkg.lock

@@ -162,7 +162,8 @@
     "prometheus",
     "prometheus/promhttp"
   ]
-  revision = "5cec1d0429b02e4323e042eb04dafdb079ddf568"
+  revision = "c5b7fccd204277076155f10851dad72b76a49317"
+  version = "v0.8.0"
 
 [[projects]]
   name = "github.com/prometheus/client_model"

vendor/github.com/prometheus/client_golang/prometheus/counter.go

@@ -30,8 +30,16 @@ type Counter interface {
 	Metric
 	Collector
 
-	// Inc increments the counter by 1. Use Add to increment it by arbitrary
-	// non-negative values.
+	// Set is used to set the Counter to an arbitrary value. It is only used
+	// if you have to transfer a value from an external counter into this
+	// Prometheus metric. Do not use it for regular handling of a
+	// Prometheus counter (as it can be used to break the contract of
+	// monotonically increasing values).
+	//
+	// Deprecated: Use NewConstMetric to create a counter for an external
+	// value. A Counter should never be set.
+	Set(float64)
+	// Inc increments the counter by 1.
 	Inc()
 	// Add adds the given value to the counter. It panics if the value is <
 	// 0.
@@ -70,12 +78,16 @@ func (c *counter) Add(v float64) {
 // if you want to count the same thing partitioned by various dimensions
 // (e.g. number of HTTP requests, partitioned by response code and
 // method). Create instances with NewCounterVec.
+//
+// CounterVec embeds MetricVec. See there for a full list of methods with
+// detailed documentation.
 type CounterVec struct {
-	*metricVec
+	*MetricVec
 }
 
 // NewCounterVec creates a new CounterVec based on the provided CounterOpts and
-// partitioned by the given label names.
+// partitioned by the given label names. At least one label name must be
+// provided.
 func NewCounterVec(opts CounterOpts, labelNames []string) *CounterVec {
 	desc := NewDesc(
 		BuildFQName(opts.Namespace, opts.Subsystem, opts.Name),
@@ -84,7 +96,7 @@ func NewCounterVec(opts CounterOpts, labelNames []string) *CounterVec {
 		opts.ConstLabels,
 	)
 	return &CounterVec{
-		metricVec: newMetricVec(desc, func(lvs ...string) Metric {
+		MetricVec: newMetricVec(desc, func(lvs ...string) Metric {
 			result := &counter{value: value{
 				desc:       desc,
 				valType:    CounterValue,
@@ -96,51 +108,22 @@ func NewCounterVec(opts CounterOpts, labelNames []string) *CounterVec {
 	}
 }
 
-// GetMetricWithLabelValues returns the Counter for the given slice of label
-// values (same order as the VariableLabels in Desc). If that combination of
-// label values is accessed for the first time, a new Counter is created.
-//
-// It is possible to call this method without using the returned Counter to only
-// create the new Counter but leave it at its starting value 0. See also the
-// SummaryVec example.
-//
-// Keeping the Counter 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 Counter from the CounterVec. In that case,
-// the Counter will still exist, but it will not be exported anymore, even if a
-// 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.
-//
-// Note that for more than one label value, this method is prone to mistakes
-// caused by an incorrect order of arguments. Consider GetMetricWith(Labels) as
-// an alternative to avoid that type of mistake. For higher label numbers, the
-// latter has a much more readable (albeit more verbose) syntax, but it comes
-// with a performance overhead (for creating and processing the Labels map).
-// See also the GaugeVec example.
+// GetMetricWithLabelValues replaces the method of the same name in
+// MetricVec. The difference is that this method returns a Counter and not a
+// Metric so that no type conversion is required.
 func (m *CounterVec) GetMetricWithLabelValues(lvs ...string) (Counter, error) {
-	metric, err := m.metricVec.getMetricWithLabelValues(lvs...)
+	metric, err := m.MetricVec.GetMetricWithLabelValues(lvs...)
 	if metric != nil {
 		return metric.(Counter), err
 	}
 	return nil, err
 }
 
-// GetMetricWith returns the Counter for the given Labels map (the label names
-// must match those of the VariableLabels in Desc). If that label map is
-// accessed for the first time, a new Counter is created. Implications of
-// creating a Counter without using it and keeping the Counter for later use are
-// the same as for GetMetricWithLabelValues.
-//
-// An error is returned if the number and names of the Labels are inconsistent
-// with those of the VariableLabels in Desc.
-//
-// This method is used for the same purpose as
-// GetMetricWithLabelValues(...string). See there for pros and cons of the two
-// methods.
+// GetMetricWith replaces the method of the same name in MetricVec. The
+// difference is that this method returns a Counter and not a Metric so that no
+// type conversion is required.
 func (m *CounterVec) GetMetricWith(labels Labels) (Counter, error) {
-	metric, err := m.metricVec.getMetricWith(labels)
+	metric, err := m.MetricVec.GetMetricWith(labels)
 	if metric != nil {
 		return metric.(Counter), err
 	}
@@ -152,14 +135,14 @@ func (m *CounterVec) GetMetricWith(labels Labels) (Counter, error) {
 // error, WithLabelValues allows shortcuts like
 //     myVec.WithLabelValues("404", "GET").Add(42)
 func (m *CounterVec) WithLabelValues(lvs ...string) Counter {
-	return m.metricVec.withLabelValues(lvs...).(Counter)
+	return m.MetricVec.WithLabelValues(lvs...).(Counter)
 }
 
 // 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)
+	return m.MetricVec.With(labels).(Counter)
 }
 
 // CounterFunc is a Counter whose value is determined at collect time by calling a

vendor/github.com/prometheus/client_golang/prometheus/desc.go

@@ -16,15 +16,33 @@ package prometheus
 import (
 	"errors"
 	"fmt"
+	"regexp"
 	"sort"
 	"strings"
 
 	"github.com/golang/protobuf/proto"
-	"github.com/prometheus/common/model"
 
 	dto "github.com/prometheus/client_model/go"
 )
 
+var (
+	metricNameRE = regexp.MustCompile(`^[a-zA-Z_][a-zA-Z0-9_:]*$`)
+	labelNameRE  = regexp.MustCompile("^[a-zA-Z_][a-zA-Z0-9_]*$")
+)
+
+// reservedLabelPrefix is a prefix which is not legal in user-supplied
+// label names.
+const reservedLabelPrefix = "__"
+
+// Labels represents a collection of label name -> value mappings. This type is
+// commonly used with the With(Labels) and GetMetricWith(Labels) methods of
+// metric vector Collectors, e.g.:
+//     myVec.With(Labels{"code": "404", "method": "GET"}).Add(42)
+//
+// The other use-case is the specification of constant label pairs in Opts or to
+// create a Desc.
+type Labels map[string]string
+
 // Desc is the descriptor used by every Prometheus Metric. It is essentially
 // the immutable meta-data of a Metric. The normal Metric implementations
 // included in this package manage their Desc under the hood. Users only have to
@@ -60,7 +78,7 @@ type Desc struct {
 	// Help string. Each Desc with the same fqName must have the same
 	// dimHash.
 	dimHash uint64
-	// err is an error that occurred during construction. It is reported on
+	// err is an error that occured during construction. It is reported on
 	// registration time.
 	err error
 }
@@ -85,7 +103,7 @@ func NewDesc(fqName, help string, variableLabels []string, constLabels Labels) *
 		d.err = errors.New("empty help string")
 		return d
 	}
-	if !model.IsValidMetricName(model.LabelValue(fqName)) {
+	if !metricNameRE.MatchString(fqName) {
 		d.err = fmt.Errorf("%q is not a valid metric name", fqName)
 		return d
 	}
@@ -109,12 +127,6 @@ func NewDesc(fqName, help string, variableLabels []string, constLabels Labels) *
 	for _, labelName := range labelNames {
 		labelValues = append(labelValues, constLabels[labelName])
 	}
-	// Validate the const label values. They can't have a wrong cardinality, so
-	// use in len(labelValues) as expectedNumberOfValues.
-	if err := validateLabelValues(labelValues, len(labelValues)); err != nil {
-		d.err = err
-		return d
-	}
 	// Now add the variable label names, but prefix them with something that
 	// cannot be in a regular label name. That prevents matching the label
 	// dimension with a different mix between preset and variable labels.
@@ -130,7 +142,6 @@ func NewDesc(fqName, help string, variableLabels []string, constLabels Labels) *
 		d.err = errors.New("duplicate label names")
 		return d
 	}
-
 	vh := hashNew()
 	for _, val := range labelValues {
 		vh = hashAdd(vh, val)
@@ -187,3 +198,8 @@ func (d *Desc) String() string {
 		d.variableLabels,
 	)
 }
+
+func checkLabelName(l string) bool {
+	return labelNameRE.MatchString(l) &&
+		!strings.HasPrefix(l, reservedLabelPrefix)
+}

vendor/github.com/prometheus/client_golang/prometheus/doc.go

@@ -17,7 +17,7 @@
 // Pushgateway (package push).
 //
 // All exported functions and methods are safe to be used concurrently unless
-// specified otherwise.
+//specified otherwise.
 //
 // A Basic Example
 //
@@ -26,7 +26,6 @@
 //    package main
 //
 //    import (
-//    	"log"
 //    	"net/http"
 //
 //    	"github.com/prometheus/client_golang/prometheus"
@@ -60,7 +59,7 @@
 //    	// The Handler function provides a default handler to expose metrics
 //    	// via an HTTP server. "/metrics" is the usual endpoint for that.
 //    	http.Handle("/metrics", promhttp.Handler())
-//    	log.Fatal(http.ListenAndServe(":8080", nil))
+//    	http.ListenAndServe(":8080", nil)
 //    }
 //
 //
@@ -70,7 +69,7 @@
 // Metrics
 //
 // The number of exported identifiers in this package might appear a bit
-// overwhelming. However, in addition to the basic plumbing shown in the example
+// overwhelming. Hovever, 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.
 //
@@ -96,8 +95,8 @@
 // SummaryVec, HistogramVec, and UntypedVec are not.
 //
 // To create instances of Metrics and their vector versions, you need a suitable
-// …Opts struct, i.e. GaugeOpts, CounterOpts, SummaryOpts, HistogramOpts, or
-// UntypedOpts.
+// …Opts struct, i.e. GaugeOpts, CounterOpts, SummaryOpts,
+// HistogramOpts, or UntypedOpts.
 //
 // Custom Collectors and constant Metrics
 //
@@ -115,8 +114,8 @@
 // Metric instances “on the fly” using NewConstMetric, NewConstHistogram, and
 // NewConstSummary (and their respective Must… versions). That will happen in
 // the Collect method. The Describe method has to return separate Desc
-// instances, representative of the “throw-away” metrics to be created later.
-// NewDesc comes in handy to create those Desc instances.
+// instances, representative of the “throw-away” metrics to be created
+// later. NewDesc comes in handy to create those Desc instances.
 //
 // The Collector example illustrates the use case. You can also look at the
 // source code of the processCollector (mirroring process metrics), the
@@ -130,34 +129,34 @@
 // Advanced Uses of the Registry
 //
 // While MustRegister is the by far most common way of registering a Collector,
-// sometimes you might want to handle the errors the registration might cause.
-// As suggested by the name, MustRegister panics if an error occurs. With the
-// Register function, the error is returned and can be handled.
+// sometimes you might want to handle the errors the registration might
+// cause. As suggested by the name, MustRegister panics if an error occurs. With
+// the Register function, the error is returned and can be handled.
 //
 // An error is returned if the registered Collector is incompatible or
 // inconsistent with already registered metrics. The registry aims for
-// consistency of the collected metrics according to the Prometheus data model.
-// Inconsistencies are ideally detected at registration time, not at collect
-// time. The former will usually be detected at start-up time of a program,
-// while the latter will only happen at scrape time, possibly not even on the
-// first scrape if the inconsistency only becomes relevant later. That is the
-// main reason why a Collector and a Metric have to describe themselves to the
-// registry.
+// consistency of the collected metrics according to the Prometheus data
+// model. Inconsistencies are ideally detected at registration time, not at
+// collect time. The former will usually be detected at start-up time of a
+// program, while the latter will only happen at scrape time, possibly not even
+// on the first scrape if the inconsistency only becomes relevant later. That is
+// the main reason why a Collector and a Metric have to describe themselves to
+// the registry.
 //
 // So far, everything we did operated on the so-called default registry, as it
-// can be found in the global DefaultRegisterer variable. With NewRegistry, you
+// can be found in the global DefaultRegistry variable. With NewRegistry, you
 // can create a custom registry, or you can even implement the Registerer or
-// Gatherer interfaces yourself. The methods Register and Unregister work in the
-// same way on a custom registry as the global functions Register and Unregister
-// on the default registry.
-//
-// There are a number of uses for custom registries: You can use registries with
-// special properties, see NewPedanticRegistry. You can avoid global state, as
-// it is imposed by the DefaultRegisterer. You can use multiple registries at
-// the same time to expose different metrics in different ways.  You can use
+// Gatherer interfaces yourself. The methods Register and Unregister work in
+// the same way on a custom registry as the global functions Register and
+// Unregister on the default registry.
+//
+// There are a number of uses for custom registries: You can use registries
+// with special properties, see NewPedanticRegistry. You can avoid global state,
+// as it is imposed by the DefaultRegistry. You can use multiple registries at
+// the same time to expose different metrics in different ways. You can use
 // separate registries for testing purposes.
 //
-// Also note that the DefaultRegisterer comes registered with a Collector for Go
+// Also note that the DefaultRegistry comes registered with a Collector for Go
 // runtime metrics (via NewGoCollector) and a Collector for process metrics (via
 // NewProcessCollector). With a custom registry, you are in control and decide
 // yourself about the Collectors to register.
@@ -167,20 +166,16 @@
 // The Registry implements the Gatherer interface. The caller of the Gather
 // method can then expose the gathered metrics in some way. Usually, the metrics
 // are served via HTTP on the /metrics endpoint. That's happening in the example
-// above. The tools to expose metrics via HTTP are in the promhttp sub-package.
-// (The top-level functions in the prometheus package are deprecated.)
+// above. The tools to expose metrics via HTTP are in the promhttp
+// sub-package. (The top-level functions in the prometheus package are
+// deprecated.)
 //
 // Pushing to the Pushgateway
 //
 // Function for pushing to the Pushgateway can be found in the push sub-package.
 //
-// Graphite Bridge
-//
-// Functions and examples to push metrics from a Gatherer to Graphite can be
-// found in the graphite sub-package.
-//
 // Other Means of Exposition
 //
-// More ways of exposing metrics can easily be added by following the approaches
-// of the existing implementations.
+// More ways of exposing metrics can easily be added. Sending metrics to
+// Graphite would be an example that will soon be implemented.
 package prometheus

vendor/github.com/prometheus/client_golang/prometheus/gauge.go

@@ -27,21 +27,16 @@ type Gauge interface {
 
 	// Set sets the Gauge to an arbitrary value.
 	Set(float64)
-	// Inc increments the Gauge by 1. Use Add to increment it by arbitrary
-	// values.
+	// Inc increments the Gauge by 1.
 	Inc()
-	// Dec decrements the Gauge by 1. Use Sub to decrement it by arbitrary
-	// values.
+	// Dec decrements the Gauge by 1.
 	Dec()
-	// Add adds the given value to the Gauge. (The value can be negative,
-	// resulting in a decrease of the Gauge.)
+	// Add adds the given value to the Gauge. (The value can be
+	// negative, resulting in a decrease of the Gauge.)
 	Add(float64)
 	// Sub subtracts the given value from the Gauge. (The value can be
 	// negative, resulting in an increase of the Gauge.)
 	Sub(float64)
-
-	// SetToCurrentTime sets the Gauge to the current Unix time in seconds.
-	SetToCurrentTime()
 }
 
 // GaugeOpts is an alias for Opts. See there for doc comments.
@@ -63,11 +58,12 @@ func NewGauge(opts GaugeOpts) Gauge {
 // (e.g. number of operations queued, partitioned by user and operation
 // type). Create instances with NewGaugeVec.
 type GaugeVec struct {
-	*metricVec
+	*MetricVec
 }
 
 // NewGaugeVec creates a new GaugeVec based on the provided GaugeOpts and
-// partitioned by the given label names.
+// partitioned by the given label names. At least one label name must be
+// provided.
 func NewGaugeVec(opts GaugeOpts, labelNames []string) *GaugeVec {
 	desc := NewDesc(
 		BuildFQName(opts.Namespace, opts.Subsystem, opts.Name),
@@ -76,57 +72,28 @@ func NewGaugeVec(opts GaugeOpts, labelNames []string) *GaugeVec {
 		opts.ConstLabels,
 	)
 	return &GaugeVec{
-		metricVec: newMetricVec(desc, func(lvs ...string) Metric {
+		MetricVec: newMetricVec(desc, func(lvs ...string) Metric {
 			return newValue(desc, GaugeValue, 0, lvs...)
 		}),
 	}
 }
 
-// GetMetricWithLabelValues returns the Gauge for the given slice of label
-// values (same order as the VariableLabels in Desc). If that combination of
-// label values is accessed for the first time, a new Gauge is created.
-//
-// It is possible to call this method without using the returned Gauge to only
-// create the new Gauge but leave it at its starting value 0. See also the
-// SummaryVec example.
-//
-// Keeping the Gauge for later use is possible (and should be considered if
-// performance is critical), but keep in mind that Reset, DeleteLabelValues and
-// Delete can be used to delete the Gauge from the GaugeVec. In that case, the
-// Gauge will still exist, but it will not be exported anymore, even if a
-// Gauge with the same label values is created later. See also the CounterVec
-// example.
-//
-// An error is returned if the number of label values is not the same as the
-// number of VariableLabels in Desc.
-//
-// 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).
+// GetMetricWithLabelValues replaces the method of the same name in
+// MetricVec. The difference is that this method returns a Gauge and not a
+// Metric so that no type conversion is required.
 func (m *GaugeVec) GetMetricWithLabelValues(lvs ...string) (Gauge, error) {
-	metric, err := m.metricVec.getMetricWithLabelValues(lvs...)
+	metric, err := m.MetricVec.GetMetricWithLabelValues(lvs...)
 	if metric != nil {
 		return metric.(Gauge), err
 	}
 	return nil, err
 }
 
-// GetMetricWith returns the Gauge for the given Labels map (the label names
-// must match those of the VariableLabels in Desc). If that label map is
-// accessed for the first time, a new Gauge is created. Implications of
-// creating a Gauge without using it and keeping the Gauge for later use are
-// the same as for GetMetricWithLabelValues.
-//
-// An error is returned if the number and names of the Labels are inconsistent
-// with those of the VariableLabels in Desc.
-//
-// This method is used for the same purpose as
-// GetMetricWithLabelValues(...string). See there for pros and cons of the two
-// methods.
+// GetMetricWith replaces the method of the same name in MetricVec. The
+// difference is that this method returns a Gauge and not a Metric so that no
+// type conversion is required.
 func (m *GaugeVec) GetMetricWith(labels Labels) (Gauge, error) {
-	metric, err := m.metricVec.getMetricWith(labels)
+	metric, err := m.MetricVec.GetMetricWith(labels)
 	if metric != nil {
 		return metric.(Gauge), err
 	}
@@ -138,14 +105,14 @@ func (m *GaugeVec) GetMetricWith(labels Labels) (Gauge, error) {
 // error, WithLabelValues allows shortcuts like
 //     myVec.WithLabelValues("404", "GET").Add(42)
 func (m *GaugeVec) WithLabelValues(lvs ...string) Gauge {
-	return m.metricVec.withLabelValues(lvs...).(Gauge)
+	return m.MetricVec.WithLabelValues(lvs...).(Gauge)
 }
 
 // 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)
+	return m.MetricVec.With(labels).(Gauge)
 }
 
 // GaugeFunc is a Gauge whose value is determined at collect time by calling a

vendor/github.com/prometheus/client_golang/prometheus/go_collector.go

@@ -8,10 +8,8 @@ import (
 )
 
 type goCollector struct {
-	goroutinesDesc *Desc
-	threadsDesc    *Desc
-	gcDesc         *Desc
-	goInfoDesc     *Desc
+	goroutines Gauge
+	gcDesc     *Desc
 
 	// metrics to describe and collect
 	metrics memStatsMetrics
@@ -21,22 +19,15 @@ type goCollector struct {
 // go process.
 func NewGoCollector() Collector {
 	return &goCollector{
-		goroutinesDesc: NewDesc(
-			"go_goroutines",
-			"Number of goroutines that currently exist.",
-			nil, nil),
-		threadsDesc: NewDesc(
-			"go_threads",
-			"Number of OS threads created.",
-			nil, nil),
+		goroutines: NewGauge(GaugeOpts{
+			Namespace: "go",
+			Name:      "goroutines",
+			Help:      "Number of goroutines that currently exist.",
+		}),
 		gcDesc: NewDesc(
 			"go_gc_duration_seconds",
 			"A summary of the GC invocation durations.",
 			nil, nil),
-		goInfoDesc: NewDesc(
-			"go_info",
-			"Information about the Go environment.",
-			nil, Labels{"version": runtime.Version()}),
 		metrics: memStatsMetrics{
 			{
 				desc: NewDesc(
@@ -57,7 +48,7 @@ func NewGoCollector() Collector {
 			}, {
 				desc: NewDesc(
 					memstatNamespace("sys_bytes"),
-					"Number of bytes obtained from system.",
+					"Number of bytes obtained by system. Sum of all system allocations.",
 					nil, nil,
 				),
 				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.Sys) },
@@ -120,12 +111,12 @@ func NewGoCollector() Collector {
 				valType: GaugeValue,
 			}, {
 				desc: NewDesc(
-					memstatNamespace("heap_released_bytes"),
-					"Number of heap bytes released to OS.",
+					memstatNamespace("heap_released_bytes_total"),
+					"Total number of heap bytes released to OS.",
 					nil, nil,
 				),
 				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.HeapReleased) },
-				valType: GaugeValue,
+				valType: CounterValue,
 			}, {
 				desc: NewDesc(
 					memstatNamespace("heap_objects"),
@@ -222,14 +213,6 @@ func NewGoCollector() Collector {
 				),
 				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.LastGC) / 1e9 },
 				valType: GaugeValue,
-			}, {
-				desc: NewDesc(
-					memstatNamespace("gc_cpu_fraction"),
-					"The fraction of this program's available CPU time used by the GC since the program started.",
-					nil, nil,
-				),
-				eval:    func(ms *runtime.MemStats) float64 { return ms.GCCPUFraction },
-				valType: GaugeValue,
 			},
 		},
 	}
@@ -241,10 +224,9 @@ func memstatNamespace(s string) string {
 
 // Describe returns all descriptions of the collector.
 func (c *goCollector) Describe(ch chan<- *Desc) {
-	ch <- c.goroutinesDesc
-	ch <- c.threadsDesc
+	ch <- c.goroutines.Desc()
 	ch <- c.gcDesc
-	ch <- c.goInfoDesc
+
 	for _, i := range c.metrics {
 		ch <- i.desc
 	}
@@ -252,9 +234,8 @@ func (c *goCollector) Describe(ch chan<- *Desc) {
 
 // Collect returns the current state of all metrics of the collector.
 func (c *goCollector) Collect(ch chan<- Metric) {
-	ch <- MustNewConstMetric(c.goroutinesDesc, GaugeValue, float64(runtime.NumGoroutine()))
-	n, _ := runtime.ThreadCreateProfile(nil)
-	ch <- MustNewConstMetric(c.threadsDesc, GaugeValue, float64(n))
+	c.goroutines.Set(float64(runtime.NumGoroutine()))
+	ch <- c.goroutines
 
 	var stats debug.GCStats
 	stats.PauseQuantiles = make([]time.Duration, 5)
@@ -267,8 +248,6 @@ func (c *goCollector) Collect(ch chan<- Metric) {
 	quantiles[0.0] = stats.PauseQuantiles[0].Seconds()
 	ch <- MustNewConstSummary(c.gcDesc, uint64(stats.NumGC), float64(stats.PauseTotal.Seconds()), quantiles)
 
-	ch <- MustNewConstMetric(c.goInfoDesc, GaugeValue, 1)
-
 	ms := &runtime.MemStats{}
 	runtime.ReadMemStats(ms)
 	for _, i := range c.metrics {

vendor/github.com/prometheus/client_golang/prometheus/histogram.go

@@ -287,11 +287,12 @@ func (h *histogram) Write(out *dto.Metric) error {
 // (e.g. HTTP request latencies, partitioned by status code and method). Create
 // instances with NewHistogramVec.
 type HistogramVec struct {
-	*metricVec
+	*MetricVec
 }
 
 // NewHistogramVec creates a new HistogramVec based on the provided HistogramOpts and
-// partitioned by the given label names.
+// partitioned by the given label names. At least one label name must be
+// provided.
 func NewHistogramVec(opts HistogramOpts, labelNames []string) *HistogramVec {
 	desc := NewDesc(
 		BuildFQName(opts.Namespace, opts.Subsystem, opts.Name),
@@ -300,60 +301,30 @@ func NewHistogramVec(opts HistogramOpts, labelNames []string) *HistogramVec {
 		opts.ConstLabels,
 	)
 	return &HistogramVec{
-		metricVec: newMetricVec(desc, func(lvs ...string) Metric {
+		MetricVec: newMetricVec(desc, func(lvs ...string) Metric {
 			return newHistogram(desc, opts, lvs...)
 		}),
 	}
 }
 
-// GetMetricWithLabelValues returns the Histogram for the given slice of label
-// values (same order as the VariableLabels in Desc). If that combination of
-// label values is accessed for the first time, a new Histogram is created.
-//
-// It is possible to call this method without using the returned Histogram to only
-// create the new Histogram but leave it at its starting value, a Histogram without
-// any observations.
-//
-// Keeping the Histogram 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 Histogram from the HistogramVec. In that case, the
-// Histogram will still exist, but it will not be exported anymore, even if a
-// Histogram with the same label values is created later. See also the CounterVec
-// example.
-//
-// An error is returned if the number of label values is not the same as the
-// number of VariableLabels in Desc.
-//
-// Note that for more than one label value, this method is prone to mistakes
-// caused by an incorrect order of arguments. Consider GetMetricWith(Labels) as
-// an alternative to avoid that type of mistake. For higher label numbers, the
-// latter has a much more readable (albeit more verbose) syntax, but it comes
-// with a performance overhead (for creating and processing the Labels map).
-// See also the GaugeVec example.
-func (m *HistogramVec) GetMetricWithLabelValues(lvs ...string) (Observer, error) {
-	metric, err := m.metricVec.getMetricWithLabelValues(lvs...)
+// GetMetricWithLabelValues replaces the method of the same name in
+// MetricVec. The difference is that this method returns a Histogram and not a
+// Metric so that no type conversion is required.
+func (m *HistogramVec) GetMetricWithLabelValues(lvs ...string) (Histogram, error) {
+	metric, err := m.MetricVec.GetMetricWithLabelValues(lvs...)
 	if metric != nil {
-		return metric.(Observer), err
+		return metric.(Histogram), err
 	}
 	return nil, err
 }
 
-// GetMetricWith returns the Histogram for the given Labels map (the label names
-// must match those of the VariableLabels in Desc). If that label map is
-// accessed for the first time, a new Histogram is created. Implications of
-// creating a Histogram without using it and keeping the Histogram for later use
-// are the same as for GetMetricWithLabelValues.
-//
-// An error is returned if the number and names of the Labels are inconsistent
-// with those of the VariableLabels in Desc.
-//
-// This method is used for the same purpose as
-// GetMetricWithLabelValues(...string). See there for pros and cons of the two
-// methods.
-func (m *HistogramVec) GetMetricWith(labels Labels) (Observer, error) {
-	metric, err := m.metricVec.getMetricWith(labels)
+// GetMetricWith replaces the method of the same name in MetricVec. The
+// difference is that this method returns a Histogram and not a Metric so that no
+// type conversion is required.
+func (m *HistogramVec) GetMetricWith(labels Labels) (Histogram, error) {
+	metric, err := m.MetricVec.GetMetricWith(labels)
 	if metric != nil {
-		return metric.(Observer), err
+		return metric.(Histogram), err
 	}
 	return nil, err
 }
@@ -362,15 +333,15 @@ func (m *HistogramVec) GetMetricWith(labels Labels) (Observer, error) {
 // GetMetricWithLabelValues would have returned an error. By not returning an
 // error, WithLabelValues allows shortcuts like
 //     myVec.WithLabelValues("404", "GET").Observe(42.21)
-func (m *HistogramVec) WithLabelValues(lvs ...string) Observer {
-	return m.metricVec.withLabelValues(lvs...).(Observer)
+func (m *HistogramVec) WithLabelValues(lvs ...string) Histogram {
+	return m.MetricVec.WithLabelValues(lvs...).(Histogram)
 }
 
 // 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)
+func (m *HistogramVec) With(labels Labels) Histogram {
+	return m.MetricVec.With(labels).(Histogram)
 }
 
 type constHistogram struct {
@@ -430,8 +401,8 @@ func NewConstHistogram(
 	buckets map[float64]uint64,
 	labelValues ...string,
 ) (Metric, error) {
-	if err := validateLabelValues(labelValues, len(desc.variableLabels)); err != nil {
-		return nil, err
+	if len(desc.variableLabels) != len(labelValues) {
+		return nil, errInconsistentCardinality
 	}
 	return &constHistogram{
 		desc:       desc,

vendor/github.com/prometheus/client_golang/prometheus/http.go

@@ -62,8 +62,7 @@ func giveBuf(buf *bytes.Buffer) {
 //
 // 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).
+// (which is non instrumented).
 func Handler() http.Handler {
 	return InstrumentHandler("prometheus", UninstrumentedHandler())
 }
@@ -96,7 +95,7 @@ func UninstrumentedHandler() http.Handler {
 			closer.Close()
 		}
 		if lastErr != nil && buf.Len() == 0 {
-			http.Error(w, "No metrics encoded, last error:\n\n"+lastErr.Error(), http.StatusInternalServerError)
+			http.Error(w, "No metrics encoded, last error:\n\n"+err.Error(), http.StatusInternalServerError)
 			return
 		}
 		header := w.Header()
@@ -159,8 +158,7 @@ func nowSeries(t ...time.Time) nower {
 // value. http_requests_total is a metric vector partitioned by HTTP method
 // (label name "method") and HTTP status code (label name "code").
 //
-// Deprecated: InstrumentHandler has several issues. Use the tooling provided in
-// package promhttp instead. The issues are the following:
+// Deprecated: InstrumentHandler has several issues:
 //
 // - It uses Summaries rather than Histograms. Summaries are not useful if
 // aggregation across multiple instances is required.
@@ -174,8 +172,9 @@ func nowSeries(t ...time.Time) nower {
 // httputil.ReverseProxy is a prominent example for a handler
 // performing such writes.
 //
-// - It has additional issues with HTTP/2, cf.
-// https://github.com/prometheus/client_golang/issues/272.
+// Upcoming versions of this package will provide ways of instrumenting HTTP
+// handlers that are more flexible and have fewer issues. Please prefer direct
+// instrumentation in the meantime.
 func InstrumentHandler(handlerName string, handler http.Handler) http.HandlerFunc {
 	return InstrumentHandlerFunc(handlerName, handler.ServeHTTP)
 }
@@ -185,13 +184,12 @@ func InstrumentHandler(handlerName string, handler http.Handler) http.HandlerFun
 // issues).
 //
 // Deprecated: InstrumentHandlerFunc is deprecated for the same reasons as
-// InstrumentHandler is. Use the tooling provided in package promhttp instead.
+// InstrumentHandler is.
 func InstrumentHandlerFunc(handlerName string, handlerFunc func(http.ResponseWriter, *http.Request)) http.HandlerFunc {
 	return InstrumentHandlerFuncWithOpts(
 		SummaryOpts{
 			Subsystem:   "http",
 			ConstLabels: Labels{"handler": handlerName},
-			Objectives:  map[float64]float64{0.5: 0.05, 0.9: 0.01, 0.99: 0.001},
 		},
 		handlerFunc,
 	)
@@ -224,7 +222,7 @@ func InstrumentHandlerFunc(handlerName string, handlerFunc func(http.ResponseWri
 // SummaryOpts.
 //
 // Deprecated: InstrumentHandlerWithOpts is deprecated for the same reasons as
-// InstrumentHandler is. Use the tooling provided in package promhttp instead.
+// InstrumentHandler is.
 func InstrumentHandlerWithOpts(opts SummaryOpts, handler http.Handler) http.HandlerFunc {
 	return InstrumentHandlerFuncWithOpts(opts, handler.ServeHTTP)
 }
@@ -235,7 +233,7 @@ func InstrumentHandlerWithOpts(opts SummaryOpts, handler http.Handler) http.Hand
 // SummaryOpts are used.
 //
 // Deprecated: InstrumentHandlerFuncWithOpts is deprecated for the same reasons
-// as InstrumentHandler is. Use the tooling provided in package promhttp instead.
+// as InstrumentHandler is.
 func InstrumentHandlerFuncWithOpts(opts SummaryOpts, handlerFunc func(http.ResponseWriter, *http.Request)) http.HandlerFunc {
 	reqCnt := NewCounterVec(
 		CounterOpts{
@@ -247,52 +245,34 @@ func InstrumentHandlerFuncWithOpts(opts SummaryOpts, handlerFunc func(http.Respo
 		},
 		instLabels,
 	)
-	if err := Register(reqCnt); err != nil {
-		if are, ok := err.(AlreadyRegisteredError); ok {
-			reqCnt = are.ExistingCollector.(*CounterVec)
-		} else {
-			panic(err)
-		}
-	}
 
 	opts.Name = "request_duration_microseconds"
 	opts.Help = "The HTTP request latencies in microseconds."
 	reqDur := NewSummary(opts)
-	if err := Register(reqDur); err != nil {
-		if are, ok := err.(AlreadyRegisteredError); ok {
-			reqDur = are.ExistingCollector.(Summary)
-		} else {
-			panic(err)
-		}
-	}
 
 	opts.Name = "request_size_bytes"
 	opts.Help = "The HTTP request sizes in bytes."
 	reqSz := NewSummary(opts)
-	if err := Register(reqSz); err != nil {
-		if are, ok := err.(AlreadyRegisteredError); ok {
-			reqSz = are.ExistingCollector.(Summary)
-		} else {
-			panic(err)
-		}
-	}
 
 	opts.Name = "response_size_bytes"
 	opts.Help = "The HTTP response sizes in bytes."
 	resSz := NewSummary(opts)
-	if err := Register(resSz); err != nil {
-		if are, ok := err.(AlreadyRegisteredError); ok {
-			resSz = are.ExistingCollector.(Summary)
-		} else {
-			panic(err)
-		}
-	}
+
+	regReqCnt := MustRegisterOrGet(reqCnt).(*CounterVec)
+	regReqDur := MustRegisterOrGet(reqDur).(Summary)
+	regReqSz := MustRegisterOrGet(reqSz).(Summary)
+	regResSz := MustRegisterOrGet(resSz).(Summary)
 
 	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		now := time.Now()
 
 		delegate := &responseWriterDelegator{ResponseWriter: w}
-		out := computeApproximateRequestSize(r)
+		out := make(chan int)
+		urlLen := 0
+		if r.URL != nil {
+			urlLen = len(r.URL.String())
+		}
+		go computeApproximateRequestSize(r, out, urlLen)
 
 		_, cn := w.(http.CloseNotifier)
 		_, fl := w.(http.Flusher)
@@ -310,44 +290,30 @@ func InstrumentHandlerFuncWithOpts(opts SummaryOpts, handlerFunc func(http.Respo
 
 		method := sanitizeMethod(r.Method)
 		code := sanitizeCode(delegate.status)
-		reqCnt.WithLabelValues(method, code).Inc()
-		reqDur.Observe(elapsed)
-		resSz.Observe(float64(delegate.written))
-		reqSz.Observe(float64(<-out))
+		regReqCnt.WithLabelValues(method, code).Inc()
+		regReqDur.Observe(elapsed)
+		regResSz.Observe(float64(delegate.written))
+		regReqSz.Observe(float64(<-out))
 	})
 }
 
-func computeApproximateRequestSize(r *http.Request) <-chan int {
-	// Get URL length in current go routine for avoiding a race condition.
-	// HandlerFunc that runs in parallel may modify the URL.
-	s := 0
-	if r.URL != nil {
-		s += len(r.URL.String())
-	}
-
-	out := make(chan int, 1)
-
-	go func() {
-		s += len(r.Method)
-		s += len(r.Proto)
-		for name, values := range r.Header {
-			s += len(name)
-			for _, value := range values {
-				s += len(value)
-			}
+func computeApproximateRequestSize(r *http.Request, out chan int, s int) {
+	s += len(r.Method)
+	s += len(r.Proto)
+	for name, values := range r.Header {
+		s += len(name)
+		for _, value := range values {
+			s += len(value)
 		}
-		s += len(r.Host)
+	}
+	s += len(r.Host)
 
-		// N.B. r.Form and r.MultipartForm are assumed to be included in r.URL.
+	// N.B. r.Form and r.MultipartForm are assumed to be included in r.URL.
 
-		if r.ContentLength != -1 {
-			s += int(r.ContentLength)
-		}
-		out <- s
-		close(out)
-	}()
-
-	return out
+	if r.ContentLength != -1 {
+		s += int(r.ContentLength)
+	}
+	out <- s
 }
 
 type responseWriterDelegator struct {

vendor/github.com/prometheus/client_golang/prometheus/labels.go

@@ -1,57 +0,0 @@
-package prometheus
-
-import (
-	"errors"
-	"fmt"
-	"strings"
-	"unicode/utf8"
-
-	"github.com/prometheus/common/model"
-)
-
-// Labels represents a collection of label name -> value mappings. This type is
-// commonly used with the With(Labels) and GetMetricWith(Labels) methods of
-// metric vector Collectors, e.g.:
-//     myVec.With(Labels{"code": "404", "method": "GET"}).Add(42)
-//
-// The other use-case is the specification of constant label pairs in Opts or to
-// create a Desc.
-type Labels map[string]string
-
-// reservedLabelPrefix is a prefix which is not legal in user-supplied
-// label names.
-const reservedLabelPrefix = "__"
-
-var errInconsistentCardinality = errors.New("inconsistent label cardinality")
-
-func validateValuesInLabels(labels Labels, expectedNumberOfValues int) error {
-	if len(labels) != expectedNumberOfValues {
-		return errInconsistentCardinality
-	}
-
-	for name, val := range labels {
-		if !utf8.ValidString(val) {
-			return fmt.Errorf("label %s: value %q is not valid UTF-8", name, val)
-		}
-	}
-
-	return nil
-}
-
-func validateLabelValues(vals []string, expectedNumberOfValues int) error {
-	if len(vals) != expectedNumberOfValues {
-		return errInconsistentCardinality
-	}
-
-	for _, val := range vals {
-		if !utf8.ValidString(val) {
-			return fmt.Errorf("label value %q is not valid UTF-8", val)
-		}
-	}
-
-	return nil
-}
-
-func checkLabelName(l string) bool {
-	return model.LabelName(l).IsValid() && !strings.HasPrefix(l, reservedLabelPrefix)
-}

vendor/github.com/prometheus/client_golang/prometheus/observer.go

@@ -1,50 +0,0 @@
-// Copyright 2017 The Prometheus Authors
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-// http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-package prometheus
-
-// Observer is the interface that wraps the Observe method, which is used by
-// Histogram and Summary to add observations.
-type Observer interface {
-	Observe(float64)
-}
-
-// The ObserverFunc type is an adapter to allow the use of ordinary
-// functions as Observers. If f is a function with the appropriate
-// signature, ObserverFunc(f) is an Observer that calls f.
-//
-// This adapter is usually used in connection with the Timer type, and there are
-// two general use cases:
-//
-// The most common one is to use a Gauge as the Observer for a Timer.
-// See the "Gauge" Timer example.
-//
-// The more advanced use case is to create a function that dynamically decides
-// which Observer to use for observing the duration. See the "Complex" Timer
-// example.
-type ObserverFunc func(float64)
-
-// Observe calls f(value). It implements Observer.
-func (f ObserverFunc) Observe(value float64) {
-	f(value)
-}
-
-// ObserverVec is an interface implemented by `HistogramVec` and `SummaryVec`.
-type ObserverVec interface {
-	GetMetricWith(Labels) (Observer, error)
-	GetMetricWithLabelValues(lvs ...string) (Observer, error)
-	With(Labels) Observer
-	WithLabelValues(...string) Observer
-
-	Collector
-}

vendor/github.com/prometheus/client_golang/prometheus/process_collector.go

@@ -19,10 +19,10 @@ type processCollector struct {
 	pid             int
 	collectFn       func(chan<- Metric)
 	pidFn           func() (int, error)
-	cpuTotal        *Desc
-	openFDs, maxFDs *Desc
-	vsize, rss      *Desc
-	startTime       *Desc
+	cpuTotal        Counter
+	openFDs, maxFDs Gauge
+	vsize, rss      Gauge
+	startTime       Gauge
 }
 
 // NewProcessCollector returns a collector which exports the current state of
@@ -44,45 +44,40 @@ func NewProcessCollectorPIDFn(
 	pidFn func() (int, error),
 	namespace string,
 ) Collector {
-	ns := ""
-	if len(namespace) > 0 {
-		ns = namespace + "_"
-	}
-
 	c := processCollector{
 		pidFn:     pidFn,
 		collectFn: func(chan<- Metric) {},
 
-		cpuTotal: NewDesc(
-			ns+"process_cpu_seconds_total",
-			"Total user and system CPU time spent in seconds.",
-			nil, nil,
-		),
-		openFDs: NewDesc(
-			ns+"process_open_fds",
-			"Number of open file descriptors.",
-			nil, nil,
-		),
-		maxFDs: NewDesc(
-			ns+"process_max_fds",
-			"Maximum number of open file descriptors.",
-			nil, nil,
-		),
-		vsize: NewDesc(
-			ns+"process_virtual_memory_bytes",
-			"Virtual memory size in bytes.",
-			nil, nil,
-		),
-		rss: NewDesc(
-			ns+"process_resident_memory_bytes",
-			"Resident memory size in bytes.",
-			nil, nil,
-		),
-		startTime: NewDesc(
-			ns+"process_start_time_seconds",
-			"Start time of the process since unix epoch in seconds.",
-			nil, nil,
-		),
+		cpuTotal: NewCounter(CounterOpts{
+			Namespace: namespace,
+			Name:      "process_cpu_seconds_total",
+			Help:      "Total user and system CPU time spent in seconds.",
+		}),
+		openFDs: NewGauge(GaugeOpts{
+			Namespace: namespace,
+			Name:      "process_open_fds",
+			Help:      "Number of open file descriptors.",
+		}),
+		maxFDs: NewGauge(GaugeOpts{
+			Namespace: namespace,
+			Name:      "process_max_fds",
+			Help:      "Maximum number of open file descriptors.",
+		}),
+		vsize: NewGauge(GaugeOpts{
+			Namespace: namespace,
+			Name:      "process_virtual_memory_bytes",
+			Help:      "Virtual memory size in bytes.",
+		}),
+		rss: NewGauge(GaugeOpts{
+			Namespace: namespace,
+			Name:      "process_resident_memory_bytes",
+			Help:      "Resident memory size in bytes.",
+		}),
+		startTime: NewGauge(GaugeOpts{
+			Namespace: namespace,
+			Name:      "process_start_time_seconds",
+			Help:      "Start time of the process since unix epoch in seconds.",
+		}),
 	}
 
 	// Set up process metric collection if supported by the runtime.
@@ -95,12 +90,12 @@ func NewProcessCollectorPIDFn(
 
 // Describe returns all descriptions of the collector.
 func (c *processCollector) Describe(ch chan<- *Desc) {
-	ch <- c.cpuTotal
-	ch <- c.openFDs
-	ch <- c.maxFDs
-	ch <- c.vsize
-	ch <- c.rss
-	ch <- c.startTime
+	ch <- c.cpuTotal.Desc()
+	ch <- c.openFDs.Desc()
+	ch <- c.maxFDs.Desc()
+	ch <- c.vsize.Desc()
+	ch <- c.rss.Desc()
+	ch <- c.startTime.Desc()
 }
 
 // Collect returns the current state of all metrics of the collector.
@@ -122,19 +117,26 @@ func (c *processCollector) processCollect(ch chan<- Metric) {
 	}
 
 	if stat, err := p.NewStat(); err == nil {
-		ch <- MustNewConstMetric(c.cpuTotal, CounterValue, stat.CPUTime())
-		ch <- MustNewConstMetric(c.vsize, GaugeValue, float64(stat.VirtualMemory()))
-		ch <- MustNewConstMetric(c.rss, GaugeValue, float64(stat.ResidentMemory()))
+		c.cpuTotal.Set(stat.CPUTime())
+		ch <- c.cpuTotal
+		c.vsize.Set(float64(stat.VirtualMemory()))
+		ch <- c.vsize
+		c.rss.Set(float64(stat.ResidentMemory()))
+		ch <- c.rss
+
 		if startTime, err := stat.StartTime(); err == nil {
-			ch <- MustNewConstMetric(c.startTime, GaugeValue, startTime)
+			c.startTime.Set(startTime)
+			ch <- c.startTime
 		}
 	}
 
 	if fds, err := p.FileDescriptorsLen(); err == nil {
-		ch <- MustNewConstMetric(c.openFDs, GaugeValue, float64(fds))
+		c.openFDs.Set(float64(fds))
+		ch <- c.openFDs
 	}
 
 	if limits, err := p.NewLimits(); err == nil {
-		ch <- MustNewConstMetric(c.maxFDs, GaugeValue, float64(limits.OpenFiles))
+		c.maxFDs.Set(float64(limits.OpenFiles))
+		ch <- c.maxFDs
 	}
 }

vendor/github.com/prometheus/client_golang/prometheus/promhttp/delegator.go

@@ -1,199 +0,0 @@
-// Copyright 2017 The Prometheus Authors
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-// http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-package promhttp
-
-import (
-	"bufio"
-	"io"
-	"net"
-	"net/http"
-)
-
-const (
-	closeNotifier = 1 << iota
-	flusher
-	hijacker
-	readerFrom
-	pusher
-)
-
-type delegator interface {
-	http.ResponseWriter
-
-	Status() int
-	Written() int64
-}
-
-type responseWriterDelegator struct {
-	http.ResponseWriter
-
-	handler, method    string
-	status             int
-	written            int64
-	wroteHeader        bool
-	observeWriteHeader func(int)
-}
-
-func (r *responseWriterDelegator) Status() int {
-	return r.status
-}
-
-func (r *responseWriterDelegator) Written() int64 {
-	return r.written
-}
-
-func (r *responseWriterDelegator) WriteHeader(code int) {
-	r.status = code
-	r.wroteHeader = true
-	r.ResponseWriter.WriteHeader(code)
-	if r.observeWriteHeader != nil {
-		r.observeWriteHeader(code)
-	}
-}
-
-func (r *responseWriterDelegator) Write(b []byte) (int, error) {
-	if !r.wroteHeader {
-		r.WriteHeader(http.StatusOK)
-	}
-	n, err := r.ResponseWriter.Write(b)
-	r.written += int64(n)
-	return n, err
-}
-
-type closeNotifierDelegator struct{ *responseWriterDelegator }
-type flusherDelegator struct{ *responseWriterDelegator }
-type hijackerDelegator struct{ *responseWriterDelegator }
-type readerFromDelegator struct{ *responseWriterDelegator }
-
-func (d *closeNotifierDelegator) CloseNotify() <-chan bool {
-	return d.ResponseWriter.(http.CloseNotifier).CloseNotify()
-}
-func (d *flusherDelegator) Flush() {
-	d.ResponseWriter.(http.Flusher).Flush()
-}
-func (d *hijackerDelegator) Hijack() (net.Conn, *bufio.ReadWriter, error) {
-	return d.ResponseWriter.(http.Hijacker).Hijack()
-}
-func (d *readerFromDelegator) ReadFrom(re io.Reader) (int64, error) {
-	if !d.wroteHeader {
-		d.WriteHeader(http.StatusOK)
-	}
-	n, err := d.ResponseWriter.(io.ReaderFrom).ReadFrom(re)
-	d.written += n
-	return n, err
-}
-
-var pickDelegator = make([]func(*responseWriterDelegator) delegator, 32)
-
-func init() {
-	// TODO(beorn7): Code generation would help here.
-	pickDelegator[0] = func(d *responseWriterDelegator) delegator { // 0
-		return d
-	}
-	pickDelegator[closeNotifier] = func(d *responseWriterDelegator) delegator { // 1
-		return closeNotifierDelegator{d}
-	}
-	pickDelegator[flusher] = func(d *responseWriterDelegator) delegator { // 2
-		return flusherDelegator{d}
-	}
-	pickDelegator[flusher+closeNotifier] = func(d *responseWriterDelegator) delegator { // 3
-		return struct {
-			*responseWriterDelegator
-			http.Flusher
-			http.CloseNotifier
-		}{d, &flusherDelegator{d}, &closeNotifierDelegator{d}}
-	}
-	pickDelegator[hijacker] = func(d *responseWriterDelegator) delegator { // 4
-		return hijackerDelegator{d}
-	}
-	pickDelegator[hijacker+closeNotifier] = func(d *responseWriterDelegator) delegator { // 5
-		return struct {
-			*responseWriterDelegator
-			http.Hijacker
-			http.CloseNotifier
-		}{d, &hijackerDelegator{d}, &closeNotifierDelegator{d}}
-	}
-	pickDelegator[hijacker+flusher] = func(d *responseWriterDelegator) delegator { // 6
-		return struct {
-			*responseWriterDelegator
-			http.Hijacker
-			http.Flusher
-		}{d, &hijackerDelegator{d}, &flusherDelegator{d}}
-	}
-	pickDelegator[hijacker+flusher+closeNotifier] = func(d *responseWriterDelegator) delegator { // 7
-		return struct {
-			*responseWriterDelegator
-			http.Hijacker
-			http.Flusher
-			http.CloseNotifier
-		}{d, &hijackerDelegator{d}, &flusherDelegator{d}, &closeNotifierDelegator{d}}
-	}
-	pickDelegator[readerFrom] = func(d *responseWriterDelegator) delegator { // 8
-		return readerFromDelegator{d}
-	}
-	pickDelegator[readerFrom+closeNotifier] = func(d *responseWriterDelegator) delegator { // 9
-		return struct {
-			*responseWriterDelegator
-			io.ReaderFrom
-			http.CloseNotifier
-		}{d, &readerFromDelegator{d}, &closeNotifierDelegator{d}}
-	}
-	pickDelegator[readerFrom+flusher] = func(d *responseWriterDelegator) delegator { // 10
-		return struct {
-			*responseWriterDelegator
-			io.ReaderFrom
-			http.Flusher
-		}{d, &readerFromDelegator{d}, &flusherDelegator{d}}
-	}
-	pickDelegator[readerFrom+flusher+closeNotifier] = func(d *responseWriterDelegator) delegator { // 11
-		return struct {
-			*responseWriterDelegator
-			io.ReaderFrom
-			http.Flusher
-			http.CloseNotifier
-		}{d, &readerFromDelegator{d}, &flusherDelegator{d}, &closeNotifierDelegator{d}}
-	}
-	pickDelegator[readerFrom+hijacker] = func(d *responseWriterDelegator) delegator { // 12
-		return struct {
-			*responseWriterDelegator
-			io.ReaderFrom
-			http.Hijacker
-		}{d, &readerFromDelegator{d}, &hijackerDelegator{d}}
-	}
-	pickDelegator[readerFrom+hijacker+closeNotifier] = func(d *responseWriterDelegator) delegator { // 13
-		return struct {
-			*responseWriterDelegator
-			io.ReaderFrom
-			http.Hijacker
-			http.CloseNotifier
-		}{d, &readerFromDelegator{d}, &hijackerDelegator{d}, &closeNotifierDelegator{d}}
-	}
-	pickDelegator[readerFrom+hijacker+flusher] = func(d *responseWriterDelegator) delegator { // 14
-		return struct {
-			*responseWriterDelegator
-			io.ReaderFrom
-			http.Hijacker
-			http.Flusher
-		}{d, &readerFromDelegator{d}, &hijackerDelegator{d}, &flusherDelegator{d}}
-	}
-	pickDelegator[readerFrom+hijacker+flusher+closeNotifier] = func(d *responseWriterDelegator) delegator { // 15
-		return struct {
-			*responseWriterDelegator
-			io.ReaderFrom
-			http.Hijacker
-			http.Flusher
-			http.CloseNotifier
-		}{d, &readerFromDelegator{d}, &hijackerDelegator{d}, &flusherDelegator{d}, &closeNotifierDelegator{d}}
-	}
-}

vendor/github.com/prometheus/client_golang/prometheus/promhttp/delegator_1_8.go

@@ -1,181 +0,0 @@
-// Copyright 2017 The Prometheus Authors
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-// http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-// +build go1.8
-
-package promhttp
-
-import (
-	"io"
-	"net/http"
-)
-
-type pusherDelegator struct{ *responseWriterDelegator }
-
-func (d *pusherDelegator) Push(target string, opts *http.PushOptions) error {
-	return d.ResponseWriter.(http.Pusher).Push(target, opts)
-}
-
-func init() {
-	pickDelegator[pusher] = func(d *responseWriterDelegator) delegator { // 16
-		return pusherDelegator{d}
-	}
-	pickDelegator[pusher+closeNotifier] = func(d *responseWriterDelegator) delegator { // 17
-		return struct {
-			*responseWriterDelegator
-			http.Pusher
-			http.CloseNotifier
-		}{d, &pusherDelegator{d}, &closeNotifierDelegator{d}}
-	}
-	pickDelegator[pusher+flusher] = func(d *responseWriterDelegator) delegator { // 18
-		return struct {
-			*responseWriterDelegator
-			http.Pusher
-			http.Flusher
-		}{d, &pusherDelegator{d}, &flusherDelegator{d}}
-	}
-	pickDelegator[pusher+flusher+closeNotifier] = func(d *responseWriterDelegator) delegator { // 19
-		return struct {
-			*responseWriterDelegator
-			http.Pusher
-			http.Flusher
-			http.CloseNotifier
-		}{d, &pusherDelegator{d}, &flusherDelegator{d}, &closeNotifierDelegator{d}}
-	}
-	pickDelegator[pusher+hijacker] = func(d *responseWriterDelegator) delegator { // 20
-		return struct {
-			*responseWriterDelegator
-			http.Pusher
-			http.Hijacker
-		}{d, &pusherDelegator{d}, &hijackerDelegator{d}}
-	}
-	pickDelegator[pusher+hijacker+closeNotifier] = func(d *responseWriterDelegator) delegator { // 21
-		return struct {
-			*responseWriterDelegator
-			http.Pusher
-			http.Hijacker
-			http.CloseNotifier
-		}{d, &pusherDelegator{d}, &hijackerDelegator{d}, &closeNotifierDelegator{d}}
-	}
-	pickDelegator[pusher+hijacker+flusher] = func(d *responseWriterDelegator) delegator { // 22
-		return struct {
-			*responseWriterDelegator
-			http.Pusher
-			http.Hijacker
-			http.Flusher
-		}{d, &pusherDelegator{d}, &hijackerDelegator{d}, &flusherDelegator{d}}
-	}
-	pickDelegator[pusher+hijacker+flusher+closeNotifier] = func(d *responseWriterDelegator) delegator { //23
-		return struct {
-			*responseWriterDelegator
-			http.Pusher
-			http.Hijacker
-			http.Flusher
-			http.CloseNotifier
-		}{d, &pusherDelegator{d}, &hijackerDelegator{d}, &flusherDelegator{d}, &closeNotifierDelegator{d}}
-	}
-	pickDelegator[pusher+readerFrom] = func(d *responseWriterDelegator) delegator { // 24
-		return struct {
-			*responseWriterDelegator
-			http.Pusher
-			io.ReaderFrom
-		}{d, &pusherDelegator{d}, &readerFromDelegator{d}}
-	}
-	pickDelegator[pusher+readerFrom+closeNotifier] = func(d *responseWriterDelegator) delegator { // 25
-		return struct {
-			*responseWriterDelegator
-			http.Pusher
-			io.ReaderFrom
-			http.CloseNotifier
-		}{d, &pusherDelegator{d}, &readerFromDelegator{d}, &closeNotifierDelegator{d}}
-	}
-	pickDelegator[pusher+readerFrom+flusher] = func(d *responseWriterDelegator) delegator { // 26
-		return struct {
-			*responseWriterDelegator
-			http.Pusher
-			io.ReaderFrom
-			http.Flusher
-		}{d, &pusherDelegator{d}, &readerFromDelegator{d}, &flusherDelegator{d}}
-	}
-	pickDelegator[pusher+readerFrom+flusher+closeNotifier] = func(d *responseWriterDelegator) delegator { // 27
-		return struct {
-			*responseWriterDelegator
-			http.Pusher
-			io.ReaderFrom
-			http.Flusher
-			http.CloseNotifier
-		}{d, &pusherDelegator{d}, &readerFromDelegator{d}, &flusherDelegator{d}, &closeNotifierDelegator{d}}
-	}
-	pickDelegator[pusher+readerFrom+hijacker] = func(d *responseWriterDelegator) delegator { // 28
-		return struct {
-			*responseWriterDelegator
-			http.Pusher
-			io.ReaderFrom
-			http.Hijacker
-		}{d, &pusherDelegator{d}, &readerFromDelegator{d}, &hijackerDelegator{d}}
-	}
-	pickDelegator[pusher+readerFrom+hijacker+closeNotifier] = func(d *responseWriterDelegator) delegator { // 29
-		return struct {
-			*responseWriterDelegator
-			http.Pusher
-			io.ReaderFrom
-			http.Hijacker
-			http.CloseNotifier
-		}{d, &pusherDelegator{d}, &readerFromDelegator{d}, &hijackerDelegator{d}, &closeNotifierDelegator{d}}
-	}
-	pickDelegator[pusher+readerFrom+hijacker+flusher] = func(d *responseWriterDelegator) delegator { // 30
-		return struct {
-			*responseWriterDelegator
-			http.Pusher
-			io.ReaderFrom
-			http.Hijacker
-			http.Flusher
-		}{d, &pusherDelegator{d}, &readerFromDelegator{d}, &hijackerDelegator{d}, &flusherDelegator{d}}
-	}
-	pickDelegator[pusher+readerFrom+hijacker+flusher+closeNotifier] = func(d *responseWriterDelegator) delegator { // 31
-		return struct {
-			*responseWriterDelegator
-			http.Pusher
-			io.ReaderFrom
-			http.Hijacker
-			http.Flusher
-			http.CloseNotifier
-		}{d, &pusherDelegator{d}, &readerFromDelegator{d}, &hijackerDelegator{d}, &flusherDelegator{d}, &closeNotifierDelegator{d}}
-	}
-}
-
-func newDelegator(w http.ResponseWriter, observeWriteHeaderFunc func(int)) delegator {
-	d := &responseWriterDelegator{
-		ResponseWriter:     w,
-		observeWriteHeader: observeWriteHeaderFunc,
-	}
-
-	id := 0
-	if _, ok := w.(http.CloseNotifier); ok {
-		id += closeNotifier
-	}
-	if _, ok := w.(http.Flusher); ok {
-		id += flusher
-	}
-	if _, ok := w.(http.Hijacker); ok {
-		id += hijacker
-	}
-	if _, ok := w.(io.ReaderFrom); ok {
-		id += readerFrom
-	}
-	if _, ok := w.(http.Pusher); ok {
-		id += pusher
-	}
-
-	return pickDelegator[id](d)
-}

vendor/github.com/prometheus/client_golang/prometheus/promhttp/delegator_pre_1_8.go

@@ -1,44 +0,0 @@
-// Copyright 2017 The Prometheus Authors
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-// http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-// +build !go1.8
-
-package promhttp
-
-import (
-	"io"
-	"net/http"
-)
-
-func newDelegator(w http.ResponseWriter, observeWriteHeaderFunc func(int)) delegator {
-	d := &responseWriterDelegator{
-		ResponseWriter:     w,
-		observeWriteHeader: observeWriteHeaderFunc,
-	}
-
-	id := 0
-	if _, ok := w.(http.CloseNotifier); ok {
-		id += closeNotifier
-	}
-	if _, ok := w.(http.Flusher); ok {
-		id += flusher
-	}
-	if _, ok := w.(http.Hijacker); ok {
-		id += hijacker
-	}
-	if _, ok := w.(io.ReaderFrom); ok {
-		id += readerFrom
-	}
-
-	return pickDelegator[id](d)
-}

vendor/github.com/prometheus/client_golang/prometheus/promhttp/http.go

@@ -11,24 +11,21 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-// Package promhttp provides tooling around HTTP servers and clients.
+// Copyright (c) 2013, The Prometheus Authors
+// All rights reserved.
 //
-// First, the package allows the creation of http.Handler instances to expose
-// Prometheus metrics via HTTP. promhttp.Handler acts on the
-// prometheus.DefaultGatherer. With HandlerFor, you can create a handler for a
-// custom registry or anything that implements the Gatherer interface. It also
-// allows the creation of handlers that act differently on errors or allow to
-// log errors.
-//
-// Second, the package provides tooling to instrument instances of http.Handler
-// via middleware. Middleware wrappers follow the naming scheme
-// InstrumentHandlerX, where X describes the intended use of the middleware.
-// See each function's doc comment for specific details.
+// Use of this source code is governed by a BSD-style license that can be found
+// in the LICENSE file.
+
+// Package promhttp contains functions to create http.Handler instances to
+// expose Prometheus metrics via HTTP. In later versions of this package, it
+// will also contain tooling to instrument instances of http.Handler and
+// http.RoundTripper.
 //
-// Finally, the package allows for an http.RoundTripper to be instrumented via
-// middleware. Middleware wrappers follow the naming scheme
-// InstrumentRoundTripperX, where X describes the intended use of the
-// middleware. See each function's doc comment for specific details.
+// promhttp.Handler acts on the prometheus.DefaultGatherer. With HandlerFor,
+// you can create a handler for a custom registry or anything that implements
+// the Gatherer interface. It also allows to create handlers that act
+// differently on errors or allow to log errors.
 package promhttp
 
 import (
@@ -128,7 +125,7 @@ func HandlerFor(reg prometheus.Gatherer, opts HandlerOpts) http.Handler {
 			closer.Close()
 		}
 		if lastErr != nil && buf.Len() == 0 {
-			http.Error(w, "No metrics encoded, last error:\n\n"+lastErr.Error(), http.StatusInternalServerError)
+			http.Error(w, "No metrics encoded, last error:\n\n"+err.Error(), http.StatusInternalServerError)
 			return
 		}
 		header := w.Header()

vendor/github.com/prometheus/client_golang/prometheus/promhttp/instrument_client.go

@@ -1,98 +0,0 @@
-// Copyright 2017 The Prometheus Authors
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-// http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-package promhttp
-
-import (
-	"net/http"
-	"time"
-
-	"github.com/prometheus/client_golang/prometheus"
-)
-
-// The RoundTripperFunc type is an adapter to allow the use of ordinary
-// functions as RoundTrippers. If f is a function with the appropriate
-// signature, RountTripperFunc(f) is a RoundTripper that calls f.
-type RoundTripperFunc func(req *http.Request) (*http.Response, error)
-
-// RoundTrip implements the RoundTripper interface.
-func (rt RoundTripperFunc) RoundTrip(r *http.Request) (*http.Response, error) {
-	return rt(r)
-}
-
-// InstrumentRoundTripperInFlight is a middleware that wraps the provided
-// http.RoundTripper. It sets the provided prometheus.Gauge to the number of
-// requests currently handled by the wrapped http.RoundTripper.
-//
-// See the example for ExampleInstrumentRoundTripperDuration for example usage.
-func InstrumentRoundTripperInFlight(gauge prometheus.Gauge, next http.RoundTripper) RoundTripperFunc {
-	return RoundTripperFunc(func(r *http.Request) (*http.Response, error) {
-		gauge.Inc()
-		defer gauge.Dec()
-		return next.RoundTrip(r)
-	})
-}
-
-// 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.
-//
-// If the wrapped RoundTripper panics or returns a non-nil error, the Counter
-// is not incremented.
-//
-// See the example for ExampleInstrumentRoundTripperDuration for example usage.
-func InstrumentRoundTripperCounter(counter *prometheus.CounterVec, next http.RoundTripper) RoundTripperFunc {
-	code, method := checkLabels(counter)
-
-	return RoundTripperFunc(func(r *http.Request) (*http.Response, error) {
-		resp, err := next.RoundTrip(r)
-		if err == nil {
-			counter.With(labels(code, method, r.Method, resp.StatusCode)).Inc()
-		}
-		return resp, err
-	})
-}
-
-// 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.
-//
-// If the wrapped RoundTripper panics or returns a non-nil error, no values are
-// reported.
-//
-// Note that this method is only guaranteed to never observe negative durations
-// if used with Go1.9+.
-func InstrumentRoundTripperDuration(obs prometheus.ObserverVec, next http.RoundTripper) RoundTripperFunc {
-	code, method := checkLabels(obs)
-
-	return RoundTripperFunc(func(r *http.Request) (*http.Response, error) {
-		start := time.Now()
-		resp, err := next.RoundTrip(r)
-		if err == nil {
-			obs.With(labels(code, method, r.Method, resp.StatusCode)).Observe(time.Since(start).Seconds())
-		}
-		return resp, err
-	})
-}

vendor/github.com/prometheus/client_golang/prometheus/promhttp/instrument_client_1_8.go

@@ -1,144 +0,0 @@
-// Copyright 2017 The Prometheus Authors
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-// http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-// +build go1.8
-
-package promhttp
-
-import (
-	"context"
-	"crypto/tls"
-	"net/http"
-	"net/http/httptrace"
-	"time"
-)
-
-// InstrumentTrace is used to offer flexibility in instrumenting the available
-// httptrace.ClientTrace hook functions. Each function is passed a float64
-// representing the time in seconds since the start of the http request. A user
-// may choose to use separately buckets Histograms, or implement custom
-// instance labels on a per function basis.
-type InstrumentTrace struct {
-	GotConn              func(float64)
-	PutIdleConn          func(float64)
-	GotFirstResponseByte func(float64)
-	Got100Continue       func(float64)
-	DNSStart             func(float64)
-	DNSDone              func(float64)
-	ConnectStart         func(float64)
-	ConnectDone          func(float64)
-	TLSHandshakeStart    func(float64)
-	TLSHandshakeDone     func(float64)
-	WroteHeaders         func(float64)
-	Wait100Continue      func(float64)
-	WroteRequest         func(float64)
-}
-
-// InstrumentRoundTripperTrace is a middleware that wraps the provided
-// RoundTripper and reports times to hook functions provided in the
-// InstrumentTrace struct. Hook functions that are not present in the provided
-// InstrumentTrace struct are ignored. Times reported to the hook functions are
-// time since the start of the request. Only with Go1.9+, those times are
-// guaranteed to never be negative. (Earlier Go versions are not using a
-// monotonic clock.) Note that partitioning of Histograms is expensive and
-// should be used judiciously.
-//
-// For hook functions that receive an error as an argument, no observations are
-// made in the event of a non-nil error value.
-//
-// See the example for ExampleInstrumentRoundTripperDuration for example usage.
-func InstrumentRoundTripperTrace(it *InstrumentTrace, next http.RoundTripper) RoundTripperFunc {
-	return RoundTripperFunc(func(r *http.Request) (*http.Response, error) {
-		start := time.Now()
-
-		trace := &httptrace.ClientTrace{
-			GotConn: func(_ httptrace.GotConnInfo) {
-				if it.GotConn != nil {
-					it.GotConn(time.Since(start).Seconds())
-				}
-			},
-			PutIdleConn: func(err error) {
-				if err != nil {
-					return
-				}
-				if it.PutIdleConn != nil {
-					it.PutIdleConn(time.Since(start).Seconds())
-				}
-			},
-			DNSStart: func(_ httptrace.DNSStartInfo) {
-				if it.DNSStart != nil {
-					it.DNSStart(time.Since(start).Seconds())
-				}
-			},
-			DNSDone: func(_ httptrace.DNSDoneInfo) {
-				if it.DNSStart != nil {
-					it.DNSStart(time.Since(start).Seconds())
-				}
-			},
-			ConnectStart: func(_, _ string) {
-				if it.ConnectStart != nil {
-					it.ConnectStart(time.Since(start).Seconds())
-				}
-			},
-			ConnectDone: func(_, _ string, err error) {
-				if err != nil {
-					return
-				}
-				if it.ConnectDone != nil {
-					it.ConnectDone(time.Since(start).Seconds())
-				}
-			},
-			GotFirstResponseByte: func() {
-				if it.GotFirstResponseByte != nil {
-					it.GotFirstResponseByte(time.Since(start).Seconds())
-				}
-			},
-			Got100Continue: func() {
-				if it.Got100Continue != nil {
-					it.Got100Continue(time.Since(start).Seconds())
-				}
-			},
-			TLSHandshakeStart: func() {
-				if it.TLSHandshakeStart != nil {
-					it.TLSHandshakeStart(time.Since(start).Seconds())
-				}
-			},
-			TLSHandshakeDone: func(_ tls.ConnectionState, err error) {
-				if err != nil {
-					return
-				}
-				if it.TLSHandshakeDone != nil {
-					it.TLSHandshakeDone(time.Since(start).Seconds())
-				}
-			},
-			WroteHeaders: func() {
-				if it.WroteHeaders != nil {
-					it.WroteHeaders(time.Since(start).Seconds())
-				}
-			},
-			Wait100Continue: func() {
-				if it.Wait100Continue != nil {
-					it.Wait100Continue(time.Since(start).Seconds())
-				}
-			},
-			WroteRequest: func(_ httptrace.WroteRequestInfo) {
-				if it.WroteRequest != nil {
-					it.WroteRequest(time.Since(start).Seconds())
-				}
-			},
-		}
-		r = r.WithContext(httptrace.WithClientTrace(context.Background(), trace))
-
-		return next.RoundTrip(r)
-	})
-}

vendor/github.com/prometheus/client_golang/prometheus/promhttp/instrument_server.go

@@ -1,440 +0,0 @@
-// Copyright 2017 The Prometheus Authors
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-// http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-package promhttp
-
-import (
-	"net/http"
-	"strconv"
-	"strings"
-	"time"
-
-	dto "github.com/prometheus/client_model/go"
-
-	"github.com/prometheus/client_golang/prometheus"
-)
-
-// magicString is used for the hacky label test in checkLabels. Remove once fixed.
-const magicString = "zZgWfBxLqvG8kc8IMv3POi2Bb0tZI3vAnBx+gBaFi9FyPzB/CzKUer1yufDa"
-
-// InstrumentHandlerInFlight is a middleware that wraps the provided
-// http.Handler. It sets the provided prometheus.Gauge to the number of
-// requests currently handled by the wrapped http.Handler.
-//
-// See the example for InstrumentHandlerDuration for example usage.
-func InstrumentHandlerInFlight(g prometheus.Gauge, next http.Handler) http.Handler {
-	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-		g.Inc()
-		defer g.Dec()
-		next.ServeHTTP(w, r)
-	})
-}
-
-// 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
-// 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.
-//
-// If the wrapped Handler panics, no values are reported.
-//
-// Note that this method is only guaranteed to never observe negative durations
-// if used with Go1.9+.
-func InstrumentHandlerDuration(obs prometheus.ObserverVec, next http.Handler) http.HandlerFunc {
-	code, method := checkLabels(obs)
-
-	if code {
-		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-			now := time.Now()
-			d := newDelegator(w, nil)
-			next.ServeHTTP(d, r)
-
-			obs.With(labels(code, method, r.Method, d.Status())).Observe(time.Since(now).Seconds())
-		})
-	}
-
-	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-		now := time.Now()
-		next.ServeHTTP(w, r)
-		obs.With(labels(code, method, r.Method, 0)).Observe(time.Since(now).Seconds())
-	})
-}
-
-// 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.
-//
-// If the wrapped Handler does not set a status code, a status code of 200 is assumed.
-//
-// If the wrapped Handler panics, the Counter is not incremented.
-//
-// See the example for InstrumentHandlerDuration for example usage.
-func InstrumentHandlerCounter(counter *prometheus.CounterVec, next http.Handler) http.HandlerFunc {
-	code, method := checkLabels(counter)
-
-	if code {
-		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-			d := newDelegator(w, nil)
-			next.ServeHTTP(d, r)
-			counter.With(labels(code, method, r.Method, d.Status())).Inc()
-		})
-	}
-
-	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-		next.ServeHTTP(w, r)
-		counter.With(labels(code, method, r.Method, 0)).Inc()
-	})
-}
-
-// 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.
-//
-// If the wrapped Handler panics before calling WriteHeader, no value is
-// reported.
-//
-// Note that this method is only guaranteed to never observe negative durations
-// if used with Go1.9+.
-//
-// See the example for InstrumentHandlerDuration for example usage.
-func InstrumentHandlerTimeToWriteHeader(obs prometheus.ObserverVec, next http.Handler) http.HandlerFunc {
-	code, method := checkLabels(obs)
-
-	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-		now := time.Now()
-		d := newDelegator(w, func(status int) {
-			obs.With(labels(code, method, r.Method, status)).Observe(time.Since(now).Seconds())
-		})
-		next.ServeHTTP(d, r)
-	})
-}
-
-// 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.
-//
-// If the wrapped Handler does not set a status code, a status code of 200 is assumed.
-//
-// If the wrapped Handler panics, no values are reported.
-//
-// See the example for InstrumentHandlerDuration for example usage.
-func InstrumentHandlerRequestSize(obs prometheus.ObserverVec, next http.Handler) http.HandlerFunc {
-	code, method := checkLabels(obs)
-
-	if code {
-		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-			d := newDelegator(w, nil)
-			next.ServeHTTP(d, r)
-			size := computeApproximateRequestSize(r)
-			obs.With(labels(code, method, r.Method, d.Status())).Observe(float64(size))
-		})
-	}
-
-	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-		next.ServeHTTP(w, r)
-		size := computeApproximateRequestSize(r)
-		obs.With(labels(code, method, r.Method, 0)).Observe(float64(size))
-	})
-}
-
-// 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.
-//
-// If the wrapped Handler does not set a status code, a status code of 200 is assumed.
-//
-// If the wrapped Handler panics, no values are reported.
-//
-// See the example for InstrumentHandlerDuration for example usage.
-func InstrumentHandlerResponseSize(obs prometheus.ObserverVec, next http.Handler) http.Handler {
-	code, method := checkLabels(obs)
-	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-		d := newDelegator(w, nil)
-		next.ServeHTTP(d, r)
-		obs.With(labels(code, method, r.Method, d.Status())).Observe(float64(d.Written()))
-	})
-}
-
-func checkLabels(c prometheus.Collector) (code bool, method bool) {
-	// TODO(beorn7): Remove this hacky way to check for instance labels
-	// once Descriptors can have their dimensionality queried.
-	var (
-		desc *prometheus.Desc
-		pm   dto.Metric
-	)
-
-	descc := make(chan *prometheus.Desc, 1)
-	c.Describe(descc)
-
-	select {
-	case desc = <-descc:
-	default:
-		panic("no description provided by collector")
-	}
-	select {
-	case <-descc:
-		panic("more than one description provided by collector")
-	default:
-	}
-
-	close(descc)
-
-	if _, err := prometheus.NewConstMetric(desc, prometheus.UntypedValue, 0); err == nil {
-		return
-	}
-	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 {
-				continue
-			}
-			switch name {
-			case "code":
-				code = true
-			case "method":
-				method = true
-			default:
-				panic("metric partitioned with non-supported labels")
-			}
-			return
-		}
-		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")
-		}
-		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")
-		}
-		code = true
-		method = true
-		return
-	}
-	panic("metric partitioned with non-supported labels")
-}
-
-// emptyLabels is a one-time allocation for non-partitioned metrics to avoid
-// unnecessary allocations on each request.
-var emptyLabels = prometheus.Labels{}
-
-func labels(code, method bool, reqMethod string, status int) prometheus.Labels {
-	if !(code || method) {
-		return emptyLabels
-	}
-	labels := prometheus.Labels{}
-
-	if code {
-		labels["code"] = sanitizeCode(status)
-	}
-	if method {
-		labels["method"] = sanitizeMethod(reqMethod)
-	}
-
-	return labels
-}
-
-func computeApproximateRequestSize(r *http.Request) int {
-	s := 0
-	if r.URL != nil {
-		s += len(r.URL.String())
-	}
-
-	s += len(r.Method)
-	s += len(r.Proto)
-	for name, values := range r.Header {
-		s += len(name)
-		for _, value := range values {
-			s += len(value)
-		}
-	}
-	s += len(r.Host)
-
-	// N.B. r.Form and r.MultipartForm are assumed to be included in r.URL.
-
-	if r.ContentLength != -1 {
-		s += int(r.ContentLength)
-	}
-	return s
-}
-
-func sanitizeMethod(m string) string {
-	switch m {
-	case "GET", "get":
-		return "get"
-	case "PUT", "put":
-		return "put"
-	case "HEAD", "head":
-		return "head"
-	case "POST", "post":
-		return "post"
-	case "DELETE", "delete":
-		return "delete"
-	case "CONNECT", "connect":
-		return "connect"
-	case "OPTIONS", "options":
-		return "options"
-	case "NOTIFY", "notify":
-		return "notify"
-	default:
-		return strings.ToLower(m)
-	}
-}
-
-// If the wrapped http.Handler has not set a status code, i.e. the value is
-// currently 0, santizeCode will return 200, for consistency with behavior in
-// the stdlib.
-func sanitizeCode(s int) string {
-	switch s {
-	case 100:
-		return "100"
-	case 101:
-		return "101"
-
-	case 200, 0:
-		return "200"
-	case 201:
-		return "201"
-	case 202:
-		return "202"
-	case 203:
-		return "203"
-	case 204:
-		return "204"
-	case 205:
-		return "205"
-	case 206:
-		return "206"
-
-	case 300:
-		return "300"
-	case 301:
-		return "301"
-	case 302:
-		return "302"
-	case 304:
-		return "304"
-	case 305:
-		return "305"
-	case 307:
-		return "307"
-
-	case 400:
-		return "400"
-	case 401:
-		return "401"
-	case 402:
-		return "402"
-	case 403:
-		return "403"
-	case 404:
-		return "404"
-	case 405:
-		return "405"
-	case 406:
-		return "406"
-	case 407:
-		return "407"
-	case 408:
-		return "408"
-	case 409:
-		return "409"
-	case 410:
-		return "410"
-	case 411:
-		return "411"
-	case 412:
-		return "412"
-	case 413:
-		return "413"
-	case 414:
-		return "414"
-	case 415:
-		return "415"
-	case 416:
-		return "416"
-	case 417:
-		return "417"
-	case 418:
-		return "418"
-
-	case 500:
-		return "500"
-	case 501:
-		return "501"
-	case 502:
-		return "502"
-	case 503:
-		return "503"
-	case 504:
-		return "504"
-	case 505:
-		return "505"
-
-	case 428:
-		return "428"
-	case 429:
-		return "429"
-	case 431:
-		return "431"
-	case 511:
-		return "511"
-
-	default:
-		return strconv.Itoa(s)
-	}
-}

vendor/github.com/prometheus/client_golang/prometheus/registry.go

@@ -20,7 +20,6 @@ import (
 	"os"
 	"sort"
 	"sync"
-	"unicode/utf8"
 
 	"github.com/golang/protobuf/proto"
 
@@ -81,7 +80,7 @@ func NewPedanticRegistry() *Registry {
 
 // Registerer is the interface for the part of a registry in charge of
 // registering and unregistering. Users of custom registries should use
-// Registerer as type for registration purposes (rather than the Registry type
+// Registerer as type for registration purposes (rather then the Registry type
 // directly). In that way, they are free to use custom Registerer implementation
 // (e.g. for testing purposes).
 type Registerer interface {
@@ -153,6 +152,38 @@ func MustRegister(cs ...Collector) {
 	DefaultRegisterer.MustRegister(cs...)
 }
 
+// RegisterOrGet registers the provided Collector with the DefaultRegisterer and
+// returns the Collector, unless an equal Collector was registered before, in
+// which case that Collector is returned.
+//
+// Deprecated: RegisterOrGet is merely a convenience function for the
+// implementation as described in the documentation for
+// AlreadyRegisteredError. As the use case is relatively rare, this function
+// will be removed in a future version of this package to clean up the
+// namespace.
+func RegisterOrGet(c Collector) (Collector, error) {
+	if err := Register(c); err != nil {
+		if are, ok := err.(AlreadyRegisteredError); ok {
+			return are.ExistingCollector, nil
+		}
+		return nil, err
+	}
+	return c, nil
+}
+
+// MustRegisterOrGet behaves like RegisterOrGet but panics instead of returning
+// an error.
+//
+// Deprecated: This is deprecated for the same reason RegisterOrGet is. See
+// there for details.
+func MustRegisterOrGet(c Collector) Collector {
+	c, err := RegisterOrGet(c)
+	if err != nil {
+		panic(err)
+	}
+	return c
+}
+
 // Unregister removes the registration of the provided Collector from the
 // DefaultRegisterer.
 //
@@ -170,6 +201,25 @@ func (gf GathererFunc) Gather() ([]*dto.MetricFamily, error) {
 	return gf()
 }
 
+// SetMetricFamilyInjectionHook replaces the DefaultGatherer with one that
+// gathers from the previous DefaultGatherers but then merges the MetricFamily
+// protobufs returned from the provided hook function with the MetricFamily
+// protobufs returned from the original DefaultGatherer.
+//
+// Deprecated: This function manipulates the DefaultGatherer variable. Consider
+// the implications, i.e. don't do this concurrently with any uses of the
+// DefaultGatherer. In the rare cases where you need to inject MetricFamily
+// protobufs directly, it is recommended to use a custom Registry and combine it
+// with a custom Gatherer using the Gatherers type (see
+// there). SetMetricFamilyInjectionHook only exists for compatibility reasons
+// with previous versions of this package.
+func SetMetricFamilyInjectionHook(hook func() []*dto.MetricFamily) {
+	DefaultGatherer = Gatherers{
+		DefaultGatherer,
+		GathererFunc(func() ([]*dto.MetricFamily, error) { return hook(), nil }),
+	}
+}
+
 // AlreadyRegisteredError is returned by the Register method if the Collector to
 // be registered has already been registered before, or a different Collector
 // that collects the same metrics has been registered before. Registration fails
@@ -244,7 +294,7 @@ func (r *Registry) Register(c Collector) error {
 	}()
 	r.mtx.Lock()
 	defer r.mtx.Unlock()
-	// Conduct various tests...
+	// Coduct various tests...
 	for desc := range descChan {
 
 		// Is the descriptor valid at all?
@@ -397,7 +447,7 @@ func (r *Registry) Gather() ([]*dto.MetricFamily, error) {
 
 	// Drain metricChan in case of premature return.
 	defer func() {
-		for range metricChan {
+		for _ = range metricChan {
 		}
 	}()
 
@@ -633,7 +683,7 @@ func (s metricSorter) Less(i, j int) bool {
 	return s[i].GetTimestampMs() < s[j].GetTimestampMs()
 }
 
-// normalizeMetricFamilies returns a MetricFamily slice with empty
+// normalizeMetricFamilies returns a MetricFamily slice whith empty
 // MetricFamilies pruned and the remaining MetricFamilies sorted by name within
 // the slice, with the contained Metrics sorted within each MetricFamily.
 func normalizeMetricFamilies(metricFamiliesByName map[string]*dto.MetricFamily) []*dto.MetricFamily {
@@ -656,7 +706,7 @@ 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
-// name. If the resulting hash is already in the provided metricHashes, an error
+// name. If the resulting hash is alread 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
@@ -680,12 +730,6 @@ 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)
-		}
-	}
-
 	// Is the metric unique (i.e. no other metric with the same name and the same label values)?
 	h := hashNew()
 	h = hashAdd(h, metricFamily.GetName())

vendor/github.com/prometheus/client_golang/prometheus/summary.go

@@ -36,10 +36,7 @@ const quantileLabel = "quantile"
 //
 // A typical use-case is the observation of request latencies. By default, a
 // Summary provides the median, the 90th and the 99th percentile of the latency
-// as rank estimations. However, the default behavior will change in the
-// upcoming v0.10 of the library. There will be no rank estiamtions at all by
-// default. For a sane transition, it is recommended to set the desired rank
-// estimations explicitly.
+// as rank estimations.
 //
 // Note that the rank estimations cannot be aggregated in a meaningful way with
 // the Prometheus query language (i.e. you cannot average or add them). If you
@@ -57,9 +54,6 @@ type Summary interface {
 }
 
 // DefObjectives are the default Summary quantile values.
-//
-// Deprecated: DefObjectives will not be used as the default objectives in
-// v0.10 of the library. The default Summary will have no quantiles then.
 var (
 	DefObjectives = map[float64]float64{0.5: 0.05, 0.9: 0.01, 0.99: 0.001}
 
@@ -81,10 +75,8 @@ const (
 )
 
 // SummaryOpts bundles the options for creating a Summary metric. It is
-// mandatory to set Name and Help to a non-empty string. While all other fields
-// are optional and can safely be left at their zero value, it is recommended to
-// explicitly set the Objectives field to the desired value as the default value
-// will change in the upcoming v0.10 of the library.
+// mandatory to set Name and Help to a non-empty string. All other fields are
+// optional and can safely be left at their zero value.
 type SummaryOpts struct {
 	// Namespace, Subsystem, and Name are components of the fully-qualified
 	// name of the Summary (created by joining these components with
@@ -121,15 +113,9 @@ type SummaryOpts struct {
 	ConstLabels Labels
 
 	// Objectives defines the quantile rank estimates with their respective
-	// absolute error. If Objectives[q] = e, then the value reported for q
-	// will be the φ-quantile value for some φ between q-e and q+e.  The
-	// default value is DefObjectives. It is used if Objectives is left at
-	// its zero value (i.e. nil). To create a Summary without Objectives,
-	// set it to an empty map (i.e. map[float64]float64{}).
-	//
-	// Deprecated: Note that the current value of DefObjectives is
-	// deprecated. It will be replaced by an empty map in v0.10 of the
-	// library. Please explicitly set Objectives to the desired value.
+	// absolute error. If Objectives[q] = e, then the value reported
+	// for q will be the φ-quantile value for some φ between q-e and q+e.
+	// The default value is DefObjectives.
 	Objectives map[float64]float64
 
 	// MaxAge defines the duration for which an observation stays relevant
@@ -197,7 +183,7 @@ func newSummary(desc *Desc, opts SummaryOpts, labelValues ...string) Summary {
 		}
 	}
 
-	if opts.Objectives == nil {
+	if len(opts.Objectives) == 0 {
 		opts.Objectives = DefObjectives
 	}
 
@@ -404,11 +390,12 @@ func (s quantSort) Less(i, j int) bool {
 // (e.g. HTTP request latencies, partitioned by status code and method). Create
 // instances with NewSummaryVec.
 type SummaryVec struct {
-	*metricVec
+	*MetricVec
 }
 
 // NewSummaryVec creates a new SummaryVec based on the provided SummaryOpts and
-// partitioned by the given label names.
+// partitioned by the given label names. At least one label name must be
+// provided.
 func NewSummaryVec(opts SummaryOpts, labelNames []string) *SummaryVec {
 	desc := NewDesc(
 		BuildFQName(opts.Namespace, opts.Subsystem, opts.Name),
@@ -417,60 +404,30 @@ func NewSummaryVec(opts SummaryOpts, labelNames []string) *SummaryVec {
 		opts.ConstLabels,
 	)
 	return &SummaryVec{
-		metricVec: newMetricVec(desc, func(lvs ...string) Metric {
+		MetricVec: newMetricVec(desc, func(lvs ...string) Metric {
 			return newSummary(desc, opts, lvs...)
 		}),
 	}
 }
 
-// GetMetricWithLabelValues returns the Summary for the given slice of label
-// values (same order as the VariableLabels in Desc). If that combination of
-// label values is accessed for the first time, a new Summary is created.
-//
-// It is possible to call this method without using the returned Summary to only
-// create the new Summary but leave it at its starting value, a Summary without
-// any observations.
-//
-// 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
-// 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.
-//
-// Note that for more than one label value, this method is prone to mistakes
-// caused by an incorrect order of arguments. Consider GetMetricWith(Labels) as
-// an alternative to avoid that type of mistake. For higher label numbers, the
-// latter has a much more readable (albeit more verbose) syntax, but it comes
-// with a performance overhead (for creating and processing the Labels map).
-// See also the GaugeVec example.
-func (m *SummaryVec) GetMetricWithLabelValues(lvs ...string) (Observer, error) {
-	metric, err := m.metricVec.getMetricWithLabelValues(lvs...)
+// GetMetricWithLabelValues replaces the method of the same name in
+// MetricVec. The difference is that this method returns a Summary and not a
+// Metric so that no type conversion is required.
+func (m *SummaryVec) GetMetricWithLabelValues(lvs ...string) (Summary, error) {
+	metric, err := m.MetricVec.GetMetricWithLabelValues(lvs...)
 	if metric != nil {
-		return metric.(Observer), err
+		return metric.(Summary), err
 	}
 	return nil, err
 }
 
-// GetMetricWith returns the Summary for the given Labels map (the label names
-// must match those of the VariableLabels in Desc). If that label map is
-// accessed for the first time, a new Summary is created. Implications of
-// creating a Summary without using it and keeping the Summary for later use are
-// the same as for GetMetricWithLabelValues.
-//
-// An error is returned if the number and names of the Labels are inconsistent
-// with those of the VariableLabels in Desc.
-//
-// This method is used for the same purpose as
-// GetMetricWithLabelValues(...string). See there for pros and cons of the two
-// methods.
-func (m *SummaryVec) GetMetricWith(labels Labels) (Observer, error) {
-	metric, err := m.metricVec.getMetricWith(labels)
+// GetMetricWith replaces the method of the same name in MetricVec. The
+// difference is that this method returns a Summary and not a Metric so that no
+// type conversion is required.
+func (m *SummaryVec) GetMetricWith(labels Labels) (Summary, error) {
+	metric, err := m.MetricVec.GetMetricWith(labels)
 	if metric != nil {
-		return metric.(Observer), err
+		return metric.(Summary), err
 	}
 	return nil, err
 }
@@ -479,15 +436,15 @@ func (m *SummaryVec) GetMetricWith(labels Labels) (Observer, error) {
 // GetMetricWithLabelValues would have returned an error. By not returning an
 // error, WithLabelValues allows shortcuts like
 //     myVec.WithLabelValues("404", "GET").Observe(42.21)
-func (m *SummaryVec) WithLabelValues(lvs ...string) Observer {
-	return m.metricVec.withLabelValues(lvs...).(Observer)
+func (m *SummaryVec) WithLabelValues(lvs ...string) Summary {
+	return m.MetricVec.WithLabelValues(lvs...).(Summary)
 }
 
 // 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)
+func (m *SummaryVec) With(labels Labels) Summary {
+	return m.MetricVec.With(labels).(Summary)
 }
 
 type constSummary struct {
@@ -548,8 +505,8 @@ func NewConstSummary(
 	quantiles map[float64]float64,
 	labelValues ...string,
 ) (Metric, error) {
-	if err := validateLabelValues(labelValues, len(desc.variableLabels)); err != nil {
-		return nil, err
+	if len(desc.variableLabels) != len(labelValues) {
+		return nil, errInconsistentCardinality
 	}
 	return &constSummary{
 		desc:       desc,

vendor/github.com/prometheus/client_golang/prometheus/timer.go

@@ -1,51 +0,0 @@
-// Copyright 2016 The Prometheus Authors
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-// http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-package prometheus
-
-import "time"
-
-// Timer is a helper type to time functions. Use NewTimer to create new
-// instances.
-type Timer struct {
-	begin    time.Time
-	observer Observer
-}
-
-// NewTimer creates a new Timer. The provided Observer is used to observe a
-// duration in seconds. Timer is usually used to time a function call in the
-// following way:
-//    func TimeMe() {
-//        timer := NewTimer(myHistogram)
-//        defer timer.ObserveDuration()
-//        // Do actual work.
-//    }
-func NewTimer(o Observer) *Timer {
-	return &Timer{
-		begin:    time.Now(),
-		observer: o,
-	}
-}
-
-// ObserveDuration records the duration passed since the Timer was created with
-// NewTimer. It calls the Observe method of the Observer provided during
-// construction with the duration in seconds as an argument. ObserveDuration is
-// usually called with a defer statement.
-//
-// Note that this method is only guaranteed to never observe negative durations
-// if used with Go1.9+.
-func (t *Timer) ObserveDuration() {
-	if t.observer != nil {
-		t.observer.Observe(time.Since(t.begin).Seconds())
-	}
-}

vendor/github.com/prometheus/client_golang/prometheus/untyped.go

@@ -13,12 +13,108 @@
 
 package prometheus
 
+// Untyped is a Metric that represents a single numerical value that can
+// arbitrarily go up and down.
+//
+// An Untyped metric works the same as a Gauge. The only difference is that to
+// no type information is implied.
+//
+// To create Untyped instances, use NewUntyped.
+type Untyped interface {
+	Metric
+	Collector
+
+	// Set sets the Untyped metric to an arbitrary value.
+	Set(float64)
+	// Inc increments the Untyped metric by 1.
+	Inc()
+	// Dec decrements the Untyped metric by 1.
+	Dec()
+	// Add adds the given value to the Untyped metric. (The value can be
+	// negative, resulting in a decrease.)
+	Add(float64)
+	// Sub subtracts the given value from the Untyped metric. (The value can
+	// be negative, resulting in an increase.)
+	Sub(float64)
+}
+
 // UntypedOpts is an alias for Opts. See there for doc comments.
 type UntypedOpts Opts
 
-// UntypedFunc works like GaugeFunc but the collected metric is of type
-// "Untyped". UntypedFunc is useful to mirror an external metric of unknown
-// type.
+// NewUntyped creates a new Untyped metric from the provided UntypedOpts.
+func NewUntyped(opts UntypedOpts) Untyped {
+	return newValue(NewDesc(
+		BuildFQName(opts.Namespace, opts.Subsystem, opts.Name),
+		opts.Help,
+		nil,
+		opts.ConstLabels,
+	), UntypedValue, 0)
+}
+
+// UntypedVec is a Collector that bundles a set of Untyped metrics that all
+// share the same Desc, but have different values for their variable
+// labels. This is used if you want to count the same thing partitioned by
+// various dimensions. Create instances with NewUntypedVec.
+type UntypedVec struct {
+	*MetricVec
+}
+
+// NewUntypedVec creates a new UntypedVec based on the provided UntypedOpts and
+// partitioned by the given label names. At least one label name must be
+// provided.
+func NewUntypedVec(opts UntypedOpts, labelNames []string) *UntypedVec {
+	desc := NewDesc(
+		BuildFQName(opts.Namespace, opts.Subsystem, opts.Name),
+		opts.Help,
+		labelNames,
+		opts.ConstLabels,
+	)
+	return &UntypedVec{
+		MetricVec: newMetricVec(desc, func(lvs ...string) Metric {
+			return newValue(desc, UntypedValue, 0, lvs...)
+		}),
+	}
+}
+
+// GetMetricWithLabelValues replaces the method of the same name in
+// MetricVec. The difference is that this method returns an Untyped and not a
+// Metric so that no type conversion is required.
+func (m *UntypedVec) GetMetricWithLabelValues(lvs ...string) (Untyped, error) {
+	metric, err := m.MetricVec.GetMetricWithLabelValues(lvs...)
+	if metric != nil {
+		return metric.(Untyped), err
+	}
+	return nil, err
+}
+
+// GetMetricWith replaces the method of the same name in MetricVec. The
+// difference is that this method returns an Untyped and not a Metric so that no
+// type conversion is required.
+func (m *UntypedVec) GetMetricWith(labels Labels) (Untyped, error) {
+	metric, err := m.MetricVec.GetMetricWith(labels)
+	if metric != nil {
+		return metric.(Untyped), err
+	}
+	return nil, err
+}
+
+// WithLabelValues works as GetMetricWithLabelValues, but panics where
+// GetMetricWithLabelValues would have returned an error. By not returning an
+// error, WithLabelValues allows shortcuts like
+//     myVec.WithLabelValues("404", "GET").Add(42)
+func (m *UntypedVec) WithLabelValues(lvs ...string) Untyped {
+	return m.MetricVec.WithLabelValues(lvs...).(Untyped)
+}
+
+// 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 *UntypedVec) With(labels Labels) Untyped {
+	return m.MetricVec.With(labels).(Untyped)
+}
+
+// UntypedFunc is an Untyped whose value is determined at collect time by
+// calling a provided function.
 //
 // To create UntypedFunc instances, use NewUntypedFunc.
 type UntypedFunc interface {

vendor/github.com/prometheus/client_golang/prometheus/value.go

@@ -14,11 +14,11 @@
 package prometheus
 
 import (
+	"errors"
 	"fmt"
 	"math"
 	"sort"
 	"sync/atomic"
-	"time"
 
 	dto "github.com/prometheus/client_model/go"
 
@@ -36,12 +36,14 @@ const (
 	UntypedValue
 )
 
+var errInconsistentCardinality = errors.New("inconsistent label cardinality")
+
 // 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
+	// valBits containst 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
@@ -78,10 +80,6 @@ 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)
 }
@@ -155,8 +153,8 @@ func (v *valueFunc) Write(out *dto.Metric) error {
 // the Collect method. NewConstMetric returns an error if the length of
 // labelValues is not consistent with the variable labels in Desc.
 func NewConstMetric(desc *Desc, valueType ValueType, value float64, labelValues ...string) (Metric, error) {
-	if err := validateLabelValues(labelValues, len(desc.variableLabels)); err != nil {
-		return nil, err
+	if len(desc.variableLabels) != len(labelValues) {
+		return nil, errInconsistentCardinality
 	}
 	return &constMetric{
 		desc:       desc,

vendor/github.com/prometheus/client_golang/prometheus/vec.go

@@ -20,12 +20,12 @@ import (
 	"github.com/prometheus/common/model"
 )
 
-// metricVec is a Collector to bundle metrics of the same name that differ in
-// their label values. metricVec is not used directly (and therefore
-// unexported). It is used as a building block for implementations of vectors of
-// a given metric type, like GaugeVec, CounterVec, SummaryVec, HistogramVec, and
-// UntypedVec.
-type metricVec struct {
+// MetricVec is a Collector to bundle metrics of the same name that
+// differ in their label values. MetricVec is usually not used directly but as a
+// building block for implementations of vectors of a given metric
+// type. GaugeVec, CounterVec, SummaryVec, and UntypedVec are examples already
+// provided in this package.
+type MetricVec struct {
 	mtx      sync.RWMutex // Protects the children.
 	children map[uint64][]metricWithLabelValues
 	desc     *Desc
@@ -35,9 +35,10 @@ type metricVec struct {
 	hashAddByte func(h uint64, b byte) uint64
 }
 
-// newMetricVec returns an initialized metricVec.
-func newMetricVec(desc *Desc, newMetric func(lvs ...string) Metric) *metricVec {
-	return &metricVec{
+// newMetricVec returns an initialized MetricVec. The concrete value is
+// returned for embedding into another struct.
+func newMetricVec(desc *Desc, newMetric func(lvs ...string) Metric) *MetricVec {
+	return &MetricVec{
 		children:    map[uint64][]metricWithLabelValues{},
 		desc:        desc,
 		newMetric:   newMetric,
@@ -55,12 +56,12 @@ type metricWithLabelValues struct {
 
 // Describe implements Collector. The length of the returned slice
 // is always one.
-func (m *metricVec) Describe(ch chan<- *Desc) {
+func (m *MetricVec) Describe(ch chan<- *Desc) {
 	ch <- m.desc
 }
 
 // Collect implements Collector.
-func (m *metricVec) Collect(ch chan<- Metric) {
+func (m *MetricVec) Collect(ch chan<- Metric) {
 	m.mtx.RLock()
 	defer m.mtx.RUnlock()
 
@@ -71,7 +72,31 @@ func (m *metricVec) Collect(ch chan<- Metric) {
 	}
 }
 
-func (m *metricVec) getMetricWithLabelValues(lvs ...string) (Metric, error) {
+// GetMetricWithLabelValues returns the Metric for the given slice of label
+// values (same order as the VariableLabels in Desc). If that combination of
+// label values is accessed for the first time, a new Metric is created.
+//
+// It is possible to call this method without using the returned Metric to only
+// create the new Metric but leave it at its start value (e.g. a Summary or
+// Histogram without any observations). See also the SummaryVec example.
+//
+// Keeping the Metric for later use is possible (and should be considered if
+// performance is critical), but keep in mind that Reset, DeleteLabelValues and
+// Delete can be used to delete the Metric from the MetricVec. In that case, the
+// Metric will still exist, but it will not be exported anymore, even if a
+// Metric with the same label values is created later. See also the CounterVec
+// example.
+//
+// An error is returned if the number of label values is not the same as the
+// number of VariableLabels in Desc.
+//
+// Note that for more than one label value, this method is prone to mistakes
+// caused by an incorrect order of arguments. Consider GetMetricWith(Labels) as
+// an alternative to avoid that type of mistake. For higher label numbers, the
+// latter has a much more readable (albeit more verbose) syntax, but it comes
+// with a performance overhead (for creating and processing the Labels map).
+// See also the GaugeVec example.
+func (m *MetricVec) GetMetricWithLabelValues(lvs ...string) (Metric, error) {
 	h, err := m.hashLabelValues(lvs)
 	if err != nil {
 		return nil, err
@@ -80,7 +105,19 @@ func (m *metricVec) getMetricWithLabelValues(lvs ...string) (Metric, error) {
 	return m.getOrCreateMetricWithLabelValues(h, lvs), nil
 }
 
-func (m *metricVec) getMetricWith(labels Labels) (Metric, error) {
+// GetMetricWith returns the Metric for the given Labels map (the label names
+// must match those of the VariableLabels in Desc). If that label map is
+// accessed for the first time, a new Metric is created. Implications of
+// creating a Metric without using it and keeping the Metric for later use are
+// the same as for GetMetricWithLabelValues.
+//
+// An error is returned if the number and names of the Labels are inconsistent
+// with those of the VariableLabels in Desc.
+//
+// This method is used for the same purpose as
+// GetMetricWithLabelValues(...string). See there for pros and cons of the two
+// methods.
+func (m *MetricVec) GetMetricWith(labels Labels) (Metric, error) {
 	h, err := m.hashLabels(labels)
 	if err != nil {
 		return nil, err
@@ -89,16 +126,22 @@ func (m *metricVec) getMetricWith(labels Labels) (Metric, error) {
 	return m.getOrCreateMetricWithLabels(h, labels), nil
 }
 
-func (m *metricVec) withLabelValues(lvs ...string) Metric {
-	metric, err := m.getMetricWithLabelValues(lvs...)
+// WithLabelValues works as GetMetricWithLabelValues, but panics if an error
+// occurs. The method allows neat syntax like:
+//     httpReqs.WithLabelValues("404", "POST").Inc()
+func (m *MetricVec) WithLabelValues(lvs ...string) Metric {
+	metric, err := m.GetMetricWithLabelValues(lvs...)
 	if err != nil {
 		panic(err)
 	}
 	return metric
 }
 
-func (m *metricVec) with(labels Labels) Metric {
-	metric, err := m.getMetricWith(labels)
+// With works as GetMetricWith, but panics if an error occurs. The method allows
+// neat syntax like:
+//     httpReqs.With(Labels{"status":"404", "method":"POST"}).Inc()
+func (m *MetricVec) With(labels Labels) Metric {
+	metric, err := m.GetMetricWith(labels)
 	if err != nil {
 		panic(err)
 	}
@@ -110,8 +153,8 @@ func (m *metricVec) with(labels Labels) Metric {
 // returns true if a metric was deleted.
 //
 // It is not an error if the number of label values is not the same as the
-// number of VariableLabels in Desc. However, such inconsistent label count can
-// never match an actual metric, so the method will always return false in that
+// number of VariableLabels in Desc.  However, such inconsistent label count can
+// never match an actual Metric, so the method will always return false in that
 // case.
 //
 // Note that for more than one label value, this method is prone to mistakes
@@ -120,7 +163,7 @@ func (m *metricVec) with(labels Labels) Metric {
 // latter has a much more readable (albeit more verbose) syntax, but it comes
 // with a performance overhead (for creating and processing the Labels map).
 // See also the CounterVec example.
-func (m *metricVec) DeleteLabelValues(lvs ...string) bool {
+func (m *MetricVec) DeleteLabelValues(lvs ...string) bool {
 	m.mtx.Lock()
 	defer m.mtx.Unlock()
 
@@ -135,13 +178,13 @@ func (m *metricVec) DeleteLabelValues(lvs ...string) bool {
 // passed in as labels. It returns true if a metric was deleted.
 //
 // It is not an error if the number and names of the Labels are inconsistent
-// with those of the VariableLabels in Desc. However, such inconsistent Labels
-// can never match an actual metric, so the method will always return false in
-// that case.
+// with those of the VariableLabels in the Desc of the MetricVec. However, such
+// inconsistent Labels can never match an actual Metric, so the method will
+// always return false in that case.
 //
 // This method is used for the same purpose as DeleteLabelValues(...string). See
 // there for pros and cons of the two methods.
-func (m *metricVec) Delete(labels Labels) bool {
+func (m *MetricVec) Delete(labels Labels) bool {
 	m.mtx.Lock()
 	defer m.mtx.Unlock()
 
@@ -156,7 +199,7 @@ func (m *metricVec) Delete(labels Labels) bool {
 // deleteByHashWithLabelValues removes the metric from the hash bucket h. If
 // there are multiple matches in the bucket, use lvs to select a metric and
 // remove only that metric.
-func (m *metricVec) deleteByHashWithLabelValues(h uint64, lvs []string) bool {
+func (m *MetricVec) deleteByHashWithLabelValues(h uint64, lvs []string) bool {
 	metrics, ok := m.children[h]
 	if !ok {
 		return false
@@ -178,7 +221,7 @@ func (m *metricVec) deleteByHashWithLabelValues(h uint64, lvs []string) bool {
 // deleteByHashWithLabels removes the metric from the hash bucket h. If there
 // are multiple matches in the bucket, use lvs to select a metric and remove
 // only that metric.
-func (m *metricVec) deleteByHashWithLabels(h uint64, labels Labels) bool {
+func (m *MetricVec) deleteByHashWithLabels(h uint64, labels Labels) bool {
 	metrics, ok := m.children[h]
 	if !ok {
 		return false
@@ -197,7 +240,7 @@ func (m *metricVec) deleteByHashWithLabels(h uint64, labels Labels) bool {
 }
 
 // Reset deletes all metrics in this vector.
-func (m *metricVec) Reset() {
+func (m *MetricVec) Reset() {
 	m.mtx.Lock()
 	defer m.mtx.Unlock()
 
@@ -206,11 +249,10 @@ func (m *metricVec) Reset() {
 	}
 }
 
-func (m *metricVec) hashLabelValues(vals []string) (uint64, error) {
-	if err := validateLabelValues(vals, len(m.desc.variableLabels)); err != nil {
-		return 0, err
+func (m *MetricVec) hashLabelValues(vals []string) (uint64, error) {
+	if len(vals) != len(m.desc.variableLabels) {
+		return 0, errInconsistentCardinality
 	}
-
 	h := hashNew()
 	for _, val := range vals {
 		h = m.hashAdd(h, val)
@@ -219,11 +261,10 @@ func (m *metricVec) hashLabelValues(vals []string) (uint64, error) {
 	return h, nil
 }
 
-func (m *metricVec) hashLabels(labels Labels) (uint64, error) {
-	if err := validateValuesInLabels(labels, len(m.desc.variableLabels)); err != nil {
-		return 0, err
+func (m *MetricVec) hashLabels(labels Labels) (uint64, error) {
+	if len(labels) != len(m.desc.variableLabels) {
+		return 0, errInconsistentCardinality
 	}
-
 	h := hashNew()
 	for _, label := range m.desc.variableLabels {
 		val, ok := labels[label]
@@ -240,9 +281,9 @@ func (m *metricVec) hashLabels(labels Labels) (uint64, error) {
 // or creates it and returns the new one.
 //
 // This function holds the mutex.
-func (m *metricVec) getOrCreateMetricWithLabelValues(hash uint64, lvs []string) Metric {
+func (m *MetricVec) getOrCreateMetricWithLabelValues(hash uint64, lvs []string) Metric {
 	m.mtx.RLock()
-	metric, ok := m.getMetricWithHashAndLabelValues(hash, lvs)
+	metric, ok := m.getMetricWithLabelValues(hash, lvs)
 	m.mtx.RUnlock()
 	if ok {
 		return metric
@@ -250,7 +291,7 @@ func (m *metricVec) getOrCreateMetricWithLabelValues(hash uint64, lvs []string)
 
 	m.mtx.Lock()
 	defer m.mtx.Unlock()
-	metric, ok = m.getMetricWithHashAndLabelValues(hash, lvs)
+	metric, ok = m.getMetricWithLabelValues(hash, lvs)
 	if !ok {
 		// Copy to avoid allocation in case wo don't go down this code path.
 		copiedLVs := make([]string, len(lvs))
@@ -265,9 +306,9 @@ func (m *metricVec) getOrCreateMetricWithLabelValues(hash uint64, lvs []string)
 // or creates it and returns the new one.
 //
 // This function holds the mutex.
-func (m *metricVec) getOrCreateMetricWithLabels(hash uint64, labels Labels) Metric {
+func (m *MetricVec) getOrCreateMetricWithLabels(hash uint64, labels Labels) Metric {
 	m.mtx.RLock()
-	metric, ok := m.getMetricWithHashAndLabels(hash, labels)
+	metric, ok := m.getMetricWithLabels(hash, labels)
 	m.mtx.RUnlock()
 	if ok {
 		return metric
@@ -275,7 +316,7 @@ 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.getMetricWithLabels(hash, labels)
 	if !ok {
 		lvs := m.extractLabelValues(labels)
 		metric = m.newMetric(lvs...)
@@ -284,9 +325,9 @@ func (m *metricVec) getOrCreateMetricWithLabels(hash uint64, labels Labels) Metr
 	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) {
+// getMetricWithLabelValues gets a metric while handling possible collisions in
+// the hash space. Must be called while holding read mutex.
+func (m *MetricVec) getMetricWithLabelValues(h uint64, lvs []string) (Metric, bool) {
 	metrics, ok := m.children[h]
 	if ok {
 		if i := m.findMetricWithLabelValues(metrics, lvs); i < len(metrics) {
@@ -296,9 +337,9 @@ func (m *metricVec) getMetricWithHashAndLabelValues(h uint64, lvs []string) (Met
 	return nil, false
 }
 
-// getMetricWithHashAndLabels gets a metric while handling possible collisions in
+// getMetricWithLabels 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) {
+func (m *MetricVec) getMetricWithLabels(h uint64, labels Labels) (Metric, bool) {
 	metrics, ok := m.children[h]
 	if ok {
 		if i := m.findMetricWithLabels(metrics, labels); i < len(metrics) {
@@ -310,7 +351,7 @@ 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 (m *MetricVec) findMetricWithLabelValues(metrics []metricWithLabelValues, lvs []string) int {
 	for i, metric := range metrics {
 		if m.matchLabelValues(metric.values, lvs) {
 			return i
@@ -321,7 +362,7 @@ func (m *metricVec) findMetricWithLabelValues(metrics []metricWithLabelValues, l
 
 // findMetricWithLabels returns the index of the matching metric or len(metrics)
 // if not found.
-func (m *metricVec) findMetricWithLabels(metrics []metricWithLabelValues, labels Labels) int {
+func (m *MetricVec) findMetricWithLabels(metrics []metricWithLabelValues, labels Labels) int {
 	for i, metric := range metrics {
 		if m.matchLabels(metric.values, labels) {
 			return i
@@ -330,7 +371,7 @@ func (m *metricVec) findMetricWithLabels(metrics []metricWithLabelValues, labels
 	return len(metrics)
 }
 
-func (m *metricVec) matchLabelValues(values []string, lvs []string) bool {
+func (m *MetricVec) matchLabelValues(values []string, lvs []string) bool {
 	if len(values) != len(lvs) {
 		return false
 	}
@@ -342,7 +383,7 @@ func (m *metricVec) matchLabelValues(values []string, lvs []string) bool {
 	return true
 }
 
-func (m *metricVec) matchLabels(values []string, labels Labels) bool {
+func (m *MetricVec) matchLabels(values []string, labels Labels) bool {
 	if len(labels) != len(values) {
 		return false
 	}
@@ -354,7 +395,7 @@ func (m *metricVec) matchLabels(values []string, labels Labels) bool {
 	return true
 }
 
-func (m *metricVec) extractLabelValues(labels Labels) []string {
+func (m *MetricVec) extractLabelValues(labels Labels) []string {
 	labelValues := make([]string, len(labels))
 	for i, k := range m.desc.variableLabels {
 		labelValues[i] = labels[k]