Merge pull request #2080 from crosbymichael/metrics

Update prometheus client and go-metrics

vendor.conf

@@ -3,13 +3,13 @@ github.com/containerd/go-runc 4f6e87ae043f859a38255247b49c9abc262d002f
 github.com/containerd/console 84eeaae905fa414d03e07bcd6c8d3f19e7cf180e
 github.com/containerd/cgroups 29da22c6171a4316169f9205ab6c49f59b5b852f
 github.com/containerd/typeurl f6943554a7e7e88b3c14aad190bf05932da84788
-github.com/docker/go-metrics 8fd5772bf1584597834c6f7961a530f06cbfbb87
+github.com/docker/go-metrics 4ea375f7759c82740c893fc030bc37088d2ec098
 github.com/docker/go-events 9461782956ad83b30282bf90e31fa6a70c255ba9
 github.com/godbus/dbus c7fdd8b5cd55e87b4e1f4e372cdb1db61dd6c66f
-github.com/prometheus/client_golang v0.8.0
+github.com/prometheus/client_golang f4fb1b73fb099f396a7f0036bf86aa8def4ed823
-github.com/prometheus/client_model fa8ad6fec33561be4280a8f0514318c79d7f6cb6
+github.com/prometheus/client_model 99fa1f4be8e564e8a6b613da7fa6f46c9edafc6c
-github.com/prometheus/common 195bde7883f7c39ea62b0d92ab7359b5327065cb
+github.com/prometheus/common 89604d197083d4781071d3c65855d24ecfb0a563
-github.com/prometheus/procfs fcdb11ccb4389efb1b210b7ffb623ab71c5fdd60
+github.com/prometheus/procfs cb4147076ac75738c9a7d279075a253c0cc5acbd
 github.com/beorn7/perks 4c0e84591b9aa9e6dcfdf3e020114cd81f89d5f9
 github.com/matttproud/golang_protobuf_extensions v1.0.0
 github.com/docker/go-units v0.3.1

vendor/github.com/docker/go-metrics/README.md

@@ -70,7 +70,7 @@ Package documentation can be found [here](https://godoc.org/github.com/docker/go
 
 ## Additional Metrics
 
-Additional metrics are also defined here that are not avaliable in the prometheus client.
+Additional metrics are also defined here that are not available in the prometheus client.
 If you need a custom metrics and it is generic enough to be used by multiple projects, define it here.
 
 

vendor/github.com/docker/go-metrics/namespace.go

@@ -66,7 +66,7 @@ func (n *Namespace) newCounterOpts(name, help string) prometheus.CounterOpts {
 	return prometheus.CounterOpts{
 		Namespace:   n.name,
 		Subsystem:   n.subsystem,
-		Name:        fmt.Sprintf("%s_%s", name, Total),
+		Name:        makeName(name, Total),
 		Help:        help,
 		ConstLabels: prometheus.Labels(n.labels),
 	}
@@ -92,7 +92,7 @@ func (n *Namespace) newTimerOpts(name, help string) prometheus.HistogramOpts {
 	return prometheus.HistogramOpts{
 		Namespace:   n.name,
 		Subsystem:   n.subsystem,
-		Name:        fmt.Sprintf("%s_%s", name, Seconds),
+		Name:        makeName(name, Seconds),
 		Help:        help,
 		ConstLabels: prometheus.Labels(n.labels),
 	}
@@ -118,7 +118,7 @@ func (n *Namespace) newGaugeOpts(name, help string, unit Unit) prometheus.GaugeO
 	return prometheus.GaugeOpts{
 		Namespace:   n.name,
 		Subsystem:   n.subsystem,
-		Name:        fmt.Sprintf("%s_%s", name, unit),
+		Name:        makeName(name, unit),
 		Help:        help,
 		ConstLabels: prometheus.Labels(n.labels),
 	}
@@ -149,9 +149,7 @@ func (n *Namespace) Add(collector prometheus.Collector) {
 }
 
 func (n *Namespace) NewDesc(name, help string, unit Unit, labels ...string) *prometheus.Desc {
-	if string(unit) != "" {
+	name = makeName(name, unit)
-		name = fmt.Sprintf("%s_%s", name, unit)
-	}
 	namespace := n.name
 	if n.subsystem != "" {
 		namespace = fmt.Sprintf("%s_%s", namespace, n.subsystem)
@@ -173,3 +171,11 @@ func mergeLabels(lbs ...Labels) Labels {
 
 	return merged
 }
+
+func makeName(name string, unit Unit) string {
+	if unit == "" {
+		return name
+	}
+
+	return fmt.Sprintf("%s_%s", name, unit)
+}

vendor/github.com/docker/go-metrics/timer.go

@@ -28,15 +28,27 @@ type Timer interface {
 
 // LabeledTimer is a timer that must have label values populated before use.
 type LabeledTimer interface {
-	WithValues(labels ...string) Timer
+	WithValues(labels ...string) *labeledTimerObserver
 }
 
 type labeledTimer struct {
 	m *prometheus.HistogramVec
 }
 
-func (lt *labeledTimer) WithValues(labels ...string) Timer {
+type labeledTimerObserver struct {
-	return &timer{m: lt.m.WithLabelValues(labels...)}
+	m prometheus.Observer
+}
+
+func (lbo *labeledTimerObserver) Update(duration time.Duration) {
+	lbo.m.Observe(duration.Seconds())
+}
+
+func (lbo *labeledTimerObserver) UpdateSince(since time.Time) {
+	lbo.m.Observe(time.Since(since).Seconds())
+}
+
+func (lt *labeledTimer) WithValues(labels ...string) *labeledTimerObserver {
+	return &labeledTimerObserver{m: lt.m.WithLabelValues(labels...)}
 }
 
 func (lt *labeledTimer) Describe(c chan<- *prometheus.Desc) {
@@ -48,7 +60,7 @@ func (lt *labeledTimer) Collect(c chan<- prometheus.Metric) {
 }
 
 type timer struct {
-	m prometheus.Histogram
+	m prometheus.Observer
 }
 
 func (t *timer) Update(duration time.Duration) {
@@ -60,9 +72,14 @@ func (t *timer) UpdateSince(since time.Time) {
 }
 
 func (t *timer) Describe(c chan<- *prometheus.Desc) {
-	t.m.Describe(c)
+	c <- t.m.(prometheus.Metric).Desc()
 }
 
 func (t *timer) Collect(c chan<- prometheus.Metric) {
-	t.m.Collect(c)
+	// Are there any observers that don't implement Collector? It is really
+	// unclear what the point of the upstream change was, but we'll let this
+	// panic if we get an observer that doesn't implement collector. In this
+	// case, we should almost always see metricVec objects, so this should
+	// never panic.
+	t.m.(prometheus.Collector).Collect(c)
 }

vendor/github.com/prometheus/client_golang/README.md

@@ -1,12 +1,15 @@
 # Prometheus Go client library
 
 [![Build Status](https://travis-ci.org/prometheus/client_golang.svg?branch=master)](https://travis-ci.org/prometheus/client_golang)
+[![Go Report Card](https://goreportcard.com/badge/github.com/prometheus/client_golang)](https://goreportcard.com/report/github.com/prometheus/client_golang)
 
 This is the [Go](http://golang.org) client library for
 [Prometheus](http://prometheus.io). It has two separate parts, one for
 instrumenting application code, and one for creating clients that talk to the
 Prometheus HTTP API.
 
+__This library requires Go1.7 or later.__
+
 ## Instrumenting applications
 
 [![code-coverage](http://gocover.io/_badge/github.com/prometheus/client_golang/prometheus)](http://gocover.io/github.com/prometheus/client_golang/prometheus) [![go-doc](https://godoc.org/github.com/prometheus/client_golang/prometheus?status.svg)](https://godoc.org/github.com/prometheus/client_golang/prometheus)
@@ -29,7 +32,8 @@ The
 [`api/prometheus` directory](https://github.com/prometheus/client_golang/tree/master/api/prometheus)
 contains the client for the
 [Prometheus HTTP API](http://prometheus.io/docs/querying/api/). It allows you
-to write Go applications that query time series data from a Prometheus server.
+to write Go applications that query time series data from a Prometheus
+server. It is still in alpha stage.
 
 ## Where is `model`, `extraction`, and `text`?
 

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

@@ -15,6 +15,10 @@ package prometheus
 
 import (
 	"errors"
+	"math"
+	"sync/atomic"
+
+	dto "github.com/prometheus/client_model/go"
 )
 
 // Counter is a Metric that represents a single numerical value that only ever
@@ -30,16 +34,8 @@ type Counter interface {
 	Metric
 	Collector
 
-	// Set is used to set the Counter to an arbitrary value. It is only used
+	// Inc increments the counter by 1. Use Add to increment it by arbitrary
-	// if you have to transfer a value from an external counter into this
+	// non-negative values.
-	// 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.
@@ -50,6 +46,14 @@ type Counter interface {
 type CounterOpts Opts
 
 // NewCounter creates a new Counter based on the provided CounterOpts.
+//
+// The returned implementation tracks the counter value in two separate
+// variables, a float64 and a uint64. The latter is used to track calls of the
+// Inc method and calls of the Add method with a value that can be represented
+// as a uint64. This allows atomic increments of the counter with optimal
+// performance. (It is common to have an Inc call in very hot execution paths.)
+// Both internal tracking values are added up in the Write method. This has to
+// be taken into account when it comes to precision and overflow behavior.
 func NewCounter(opts CounterOpts) Counter {
 	desc := NewDesc(
 		BuildFQName(opts.Namespace, opts.Subsystem, opts.Name),
@@ -57,20 +61,58 @@ func NewCounter(opts CounterOpts) Counter {
 		nil,
 		opts.ConstLabels,
 	)
-	result := &counter{value: value{desc: desc, valType: CounterValue, labelPairs: desc.constLabelPairs}}
+	result := &counter{desc: desc, labelPairs: desc.constLabelPairs}
 	result.init(result) // Init self-collection.
 	return result
 }
 
 type counter struct {
-	value
+	// valBits contains the bits of the represented float64 value, while
+	// valInt stores values that are exact integers. Both have to go first
+	// in the struct to guarantee alignment for atomic operations.
+	// http://golang.org/pkg/sync/atomic/#pkg-note-BUG
+	valBits uint64
+	valInt  uint64
+
+	selfCollector
+	desc *Desc
+
+	labelPairs []*dto.LabelPair
+}
+
+func (c *counter) Desc() *Desc {
+	return c.desc
 }
 
 func (c *counter) Add(v float64) {
 	if v < 0 {
 		panic(errors.New("counter cannot decrease in value"))
 	}
-	c.value.Add(v)
+	ival := uint64(v)
+	if float64(ival) == v {
+		atomic.AddUint64(&c.valInt, ival)
+		return
+	}
+
+	for {
+		oldBits := atomic.LoadUint64(&c.valBits)
+		newBits := math.Float64bits(math.Float64frombits(oldBits) + v)
+		if atomic.CompareAndSwapUint64(&c.valBits, oldBits, newBits) {
+			return
+		}
+	}
+}
+
+func (c *counter) Inc() {
+	atomic.AddUint64(&c.valInt, 1)
+}
+
+func (c *counter) Write(out *dto.Metric) error {
+	fval := math.Float64frombits(atomic.LoadUint64(&c.valBits))
+	ival := atomic.LoadUint64(&c.valInt)
+	val := fval + float64(ival)
+
+	return populateMetric(CounterValue, val, c.labelPairs, out)
 }
 
 // CounterVec is a Collector that bundles a set of Counters that all share the
@@ -78,16 +120,12 @@ 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. At least one label name must be
+// partitioned by the given label names.
-// provided.
 func NewCounterVec(opts CounterOpts, labelNames []string) *CounterVec {
 	desc := NewDesc(
 		BuildFQName(opts.Namespace, opts.Subsystem, opts.Name),
@@ -96,34 +134,62 @@ 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{
+			if len(lvs) != len(desc.variableLabels) {
-				desc:       desc,
+				panic(errInconsistentCardinality)
-				valType:    CounterValue,
+			}
-				labelPairs: makeLabelPairs(desc, lvs),
+			result := &counter{desc: desc, labelPairs: makeLabelPairs(desc, lvs)}
-			}}
 			result.init(result) // Init self-collection.
 			return result
 		}),
 	}
 }
 
-// GetMetricWithLabelValues replaces the method of the same name in
+// GetMetricWithLabelValues returns the Counter for the given slice of label
-// MetricVec. The difference is that this method returns a Counter and not a
+// values (same order as the VariableLabels in Desc). If that combination of
-// Metric so that no type conversion is required.
+// label values is accessed for the first time, a new Counter is created.
-func (m *CounterVec) GetMetricWithLabelValues(lvs ...string) (Counter, error) {
+//
-	metric, err := m.MetricVec.GetMetricWithLabelValues(lvs...)
+// 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 (minus any curried labels).
+//
+// Note that for more than one label value, this method is prone to mistakes
+// caused by an incorrect order of arguments. Consider GetMetricWith(Labels) as
+// an alternative to avoid that type of mistake. For higher label numbers, the
+// latter has a much more readable (albeit more verbose) syntax, but it comes
+// with a performance overhead (for creating and processing the Labels map).
+// See also the GaugeVec example.
+func (v *CounterVec) GetMetricWithLabelValues(lvs ...string) (Counter, error) {
+	metric, err := v.metricVec.getMetricWithLabelValues(lvs...)
 	if metric != nil {
 		return metric.(Counter), err
 	}
 	return nil, err
 }
 
-// GetMetricWith replaces the method of the same name in MetricVec. The
+// GetMetricWith returns the Counter for the given Labels map (the label names
-// difference is that this method returns a Counter and not a Metric so that no
+// must match those of the VariableLabels in Desc). If that label map is
-// type conversion is required.
+// accessed for the first time, a new Counter is created. Implications of
-func (m *CounterVec) GetMetricWith(labels Labels) (Counter, error) {
+// creating a Counter without using it and keeping the Counter for later use are
-	metric, err := m.MetricVec.GetMetricWith(labels)
+// 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 (minus any curried labels).
+//
+// This method is used for the same purpose as
+// GetMetricWithLabelValues(...string). See there for pros and cons of the two
+// methods.
+func (v *CounterVec) GetMetricWith(labels Labels) (Counter, error) {
+	metric, err := v.metricVec.getMetricWith(labels)
 	if metric != nil {
 		return metric.(Counter), err
 	}
@@ -131,18 +197,57 @@ func (m *CounterVec) GetMetricWith(labels Labels) (Counter, error) {
 }
 
 // WithLabelValues works as GetMetricWithLabelValues, but panics where
-// GetMetricWithLabelValues would have returned an error. By not returning an
+// GetMetricWithLabelValues would have returned an error. Not returning an
-// error, WithLabelValues allows shortcuts like
+// error allows shortcuts like
 //     myVec.WithLabelValues("404", "GET").Add(42)
-func (m *CounterVec) WithLabelValues(lvs ...string) Counter {
+func (v *CounterVec) WithLabelValues(lvs ...string) Counter {
-	return m.MetricVec.WithLabelValues(lvs...).(Counter)
+	c, err := v.GetMetricWithLabelValues(lvs...)
+	if err != nil {
+		panic(err)
+	}
+	return c
 }
 
 // With works as GetMetricWith, but panics where GetMetricWithLabels would have
-// returned an error. By not returning an error, With allows shortcuts like
+// returned an error. Not returning an error allows shortcuts like
-//     myVec.With(Labels{"code": "404", "method": "GET"}).Add(42)
+//     myVec.With(prometheus.Labels{"code": "404", "method": "GET"}).Add(42)
-func (m *CounterVec) With(labels Labels) Counter {
+func (v *CounterVec) With(labels Labels) Counter {
-	return m.MetricVec.With(labels).(Counter)
+	c, err := v.GetMetricWith(labels)
+	if err != nil {
+		panic(err)
+	}
+	return c
+}
+
+// CurryWith returns a vector curried with the provided labels, i.e. the
+// returned vector has those labels pre-set for all labeled operations performed
+// on it. The cardinality of the curried vector is reduced accordingly. The
+// order of the remaining labels stays the same (just with the curried labels
+// taken out of the sequence – which is relevant for the
+// (GetMetric)WithLabelValues methods). It is possible to curry a curried
+// vector, but only with labels not yet used for currying before.
+//
+// The metrics contained in the CounterVec are shared between the curried and
+// uncurried vectors. They are just accessed differently. Curried and uncurried
+// vectors behave identically in terms of collection. Only one must be
+// registered with a given registry (usually the uncurried version). The Reset
+// method deletes all metrics, even if called on a curried vector.
+func (v *CounterVec) CurryWith(labels Labels) (*CounterVec, error) {
+	vec, err := v.curryWith(labels)
+	if vec != nil {
+		return &CounterVec{vec}, err
+	}
+	return nil, err
+}
+
+// MustCurryWith works as CurryWith but panics where CurryWith would have
+// returned an error.
+func (v *CounterVec) MustCurryWith(labels Labels) *CounterVec {
+	vec, err := v.CurryWith(labels)
+	if err != nil {
+		panic(err)
+	}
+	return vec
 }
 
 // CounterFunc is a Counter whose value is determined at collect time by calling a

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

@@ -16,33 +16,15 @@ 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
@@ -78,7 +60,7 @@ type Desc struct {
 	// Help string. Each Desc with the same fqName must have the same
 	// dimHash.
 	dimHash uint64
-	// err is an error that occured during construction. It is reported on
+	// err is an error that occurred during construction. It is reported on
 	// registration time.
 	err error
 }
@@ -91,8 +73,7 @@ type Desc struct {
 // and therefore not part of the Desc. (They are managed within the Metric.)
 //
 // For constLabels, the label values are constant. Therefore, they are fully
-// specified in the Desc. See the Opts documentation for the implications of
+// specified in the Desc. See the Collector example for a usage pattern.
-// constant labels.
 func NewDesc(fqName, help string, variableLabels []string, constLabels Labels) *Desc {
 	d := &Desc{
 		fqName:         fqName,
@@ -103,7 +84,7 @@ func NewDesc(fqName, help string, variableLabels []string, constLabels Labels) *
 		d.err = errors.New("empty help string")
 		return d
 	}
-	if !metricNameRE.MatchString(fqName) {
+	if !model.IsValidMetricName(model.LabelValue(fqName)) {
 		d.err = fmt.Errorf("%q is not a valid metric name", fqName)
 		return d
 	}
@@ -127,6 +108,12 @@ 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.
@@ -142,6 +129,7 @@ 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)
@@ -198,8 +186,3 @@ 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
 //
@@ -26,6 +26,7 @@
 //    package main
 //
 //    import (
+//    	"log"
 //    	"net/http"
 //
 //    	"github.com/prometheus/client_golang/prometheus"
@@ -59,7 +60,7 @@
 //    	// 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())
-//    	http.ListenAndServe(":8080", nil)
+//    	log.Fatal(http.ListenAndServe(":8080", nil))
 //    }
 //
 //
@@ -69,7 +70,7 @@
 // Metrics
 //
 // The number of exported identifiers in this package might appear a bit
-// overwhelming. Hovever, in addition to the basic plumbing shown in the example
+// overwhelming. However, in addition to the basic plumbing shown in the example
 // above, you only need to understand the different metric types and their
 // vector versions for basic usage.
 //
@@ -95,8 +96,8 @@
 // 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,
+// …Opts struct, i.e. GaugeOpts, CounterOpts, SummaryOpts, HistogramOpts, or
-// HistogramOpts, or UntypedOpts.
+// UntypedOpts.
 //
 // Custom Collectors and constant Metrics
 //
@@ -114,8 +115,8 @@
 // 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
+// instances, representative of the “throw-away” metrics to be created later.
-// later. NewDesc comes in handy to create those Desc instances.
+// 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
@@ -129,34 +130,34 @@
 // 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
+// sometimes you might want to handle the errors the registration might cause.
-// cause. As suggested by the name, MustRegister panics if an error occurs. With
+// As suggested by the name, MustRegister panics if an error occurs. With the
-// the Register function, the error is returned and can be handled.
+// 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
+// consistency of the collected metrics according to the Prometheus data model.
-// model. Inconsistencies are ideally detected at registration time, not at
+// Inconsistencies are ideally detected at registration time, not at collect
-// collect time. The former will usually be detected at start-up time of a
+// time. The former will usually be detected at start-up time of a program,
-// program, while the latter will only happen at scrape time, possibly not even
+// while the latter will only happen at scrape time, possibly not even on the
-// on the first scrape if the inconsistency only becomes relevant later. That is
+// first scrape if the inconsistency only becomes relevant later. That is the
-// the main reason why a Collector and a Metric have to describe themselves to
+// main reason why a Collector and a Metric have to describe themselves to the
-// the registry.
+// registry.
 //
 // So far, everything we did operated on the so-called default registry, as it
-// can be found in the global DefaultRegistry variable. With NewRegistry, you
+// can be found in the global DefaultRegisterer 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
+// Gatherer interfaces yourself. The methods Register and Unregister work in the
-// the same way on a custom registry as the global functions Register and
+// same way on a custom registry as the global functions Register and Unregister
-// Unregister on the default registry.
+// on the default registry.
 //
-// There are a number of uses for custom registries: You can use registries
+// There are a number of uses for custom registries: You can use registries with
-// with special properties, see NewPedanticRegistry. You can avoid global state,
+// special properties, see NewPedanticRegistry. You can avoid global state, as
-// as it is imposed by the DefaultRegistry. You can use multiple registries at
+// 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
+// the same time to expose different metrics in different ways.  You can use
 // separate registries for testing purposes.
 //
-// Also note that the DefaultRegistry comes registered with a Collector for Go
+// Also note that the DefaultRegisterer 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.
@@ -166,16 +167,20 @@
 // 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
+// above. The tools to expose metrics via HTTP are in the promhttp sub-package.
-// sub-package. (The top-level functions in the prometheus package are
+// (The top-level functions in the prometheus package are deprecated.)
-// 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. Sending metrics to
+// More ways of exposing metrics can easily be added by following the approaches
-// Graphite would be an example that will soon be implemented.
+// of the existing implementations.
 package prometheus

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

@@ -13,6 +13,14 @@
 
 package prometheus
 
+import (
+	"math"
+	"sync/atomic"
+	"time"
+
+	dto "github.com/prometheus/client_model/go"
+)
+
 // Gauge is a Metric that represents a single numerical value that can
 // arbitrarily go up and down.
 //
@@ -27,29 +35,95 @@ type Gauge interface {
 
 	// Set sets the Gauge to an arbitrary value.
 	Set(float64)
-	// Inc increments the Gauge by 1.
+	// Inc increments the Gauge by 1. Use Add to increment it by arbitrary
+	// values.
 	Inc()
-	// Dec decrements the Gauge by 1.
+	// Dec decrements the Gauge by 1. Use Sub to decrement it by arbitrary
+	// values.
 	Dec()
-	// Add adds the given value to the Gauge. (The value can be
+	// Add adds the given value to the Gauge. (The value can be negative,
-	// negative, resulting in a decrease of the Gauge.)
+	// 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.
 type GaugeOpts Opts
 
 // NewGauge creates a new Gauge based on the provided GaugeOpts.
+//
+// The returned implementation is optimized for a fast Set method. If you have a
+// choice for managing the value of a Gauge via Set vs. Inc/Dec/Add/Sub, pick
+// the former. For example, the Inc method of the returned Gauge is slower than
+// the Inc method of a Counter returned by NewCounter. This matches the typical
+// scenarios for Gauges and Counters, where the former tends to be Set-heavy and
+// the latter Inc-heavy.
 func NewGauge(opts GaugeOpts) Gauge {
-	return newValue(NewDesc(
+	desc := NewDesc(
 		BuildFQName(opts.Namespace, opts.Subsystem, opts.Name),
 		opts.Help,
 		nil,
 		opts.ConstLabels,
-	), GaugeValue, 0)
+	)
+	result := &gauge{desc: desc, labelPairs: desc.constLabelPairs}
+	result.init(result) // Init self-collection.
+	return result
+}
+
+type gauge struct {
+	// valBits contains the bits of the represented float64 value. It has
+	// to go first in the struct to guarantee alignment for atomic
+	// operations.  http://golang.org/pkg/sync/atomic/#pkg-note-BUG
+	valBits uint64
+
+	selfCollector
+
+	desc       *Desc
+	labelPairs []*dto.LabelPair
+}
+
+func (g *gauge) Desc() *Desc {
+	return g.desc
+}
+
+func (g *gauge) Set(val float64) {
+	atomic.StoreUint64(&g.valBits, math.Float64bits(val))
+}
+
+func (g *gauge) SetToCurrentTime() {
+	g.Set(float64(time.Now().UnixNano()) / 1e9)
+}
+
+func (g *gauge) Inc() {
+	g.Add(1)
+}
+
+func (g *gauge) Dec() {
+	g.Add(-1)
+}
+
+func (g *gauge) Add(val float64) {
+	for {
+		oldBits := atomic.LoadUint64(&g.valBits)
+		newBits := math.Float64bits(math.Float64frombits(oldBits) + val)
+		if atomic.CompareAndSwapUint64(&g.valBits, oldBits, newBits) {
+			return
+		}
+	}
+}
+
+func (g *gauge) Sub(val float64) {
+	g.Add(val * -1)
+}
+
+func (g *gauge) Write(out *dto.Metric) error {
+	val := math.Float64frombits(atomic.LoadUint64(&g.valBits))
+	return populateMetric(GaugeValue, val, g.labelPairs, out)
 }
 
 // GaugeVec is a Collector that bundles a set of Gauges that all share the same
@@ -58,12 +132,11 @@ 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. At least one label name must be
+// partitioned by the given label names.
-// provided.
 func NewGaugeVec(opts GaugeOpts, labelNames []string) *GaugeVec {
 	desc := NewDesc(
 		BuildFQName(opts.Namespace, opts.Subsystem, opts.Name),
@@ -72,28 +145,62 @@ 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...)
+			if len(lvs) != len(desc.variableLabels) {
+				panic(errInconsistentCardinality)
+			}
+			result := &gauge{desc: desc, labelPairs: makeLabelPairs(desc, lvs)}
+			result.init(result) // Init self-collection.
+			return result
 		}),
 	}
 }
 
-// GetMetricWithLabelValues replaces the method of the same name in
+// GetMetricWithLabelValues returns the Gauge for the given slice of label
-// MetricVec. The difference is that this method returns a Gauge and not a
+// values (same order as the VariableLabels in Desc). If that combination of
-// Metric so that no type conversion is required.
+// label values is accessed for the first time, a new Gauge is created.
-func (m *GaugeVec) GetMetricWithLabelValues(lvs ...string) (Gauge, error) {
+//
-	metric, err := m.MetricVec.GetMetricWithLabelValues(lvs...)
+// 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 (minus any curried labels).
+//
+// Note that for more than one label value, this method is prone to mistakes
+// caused by an incorrect order of arguments. Consider GetMetricWith(Labels) as
+// an alternative to avoid that type of mistake. For higher label numbers, the
+// latter has a much more readable (albeit more verbose) syntax, but it comes
+// with a performance overhead (for creating and processing the Labels map).
+func (v *GaugeVec) GetMetricWithLabelValues(lvs ...string) (Gauge, error) {
+	metric, err := v.metricVec.getMetricWithLabelValues(lvs...)
 	if metric != nil {
 		return metric.(Gauge), err
 	}
 	return nil, err
 }
 
-// GetMetricWith replaces the method of the same name in MetricVec. The
+// GetMetricWith returns the Gauge for the given Labels map (the label names
-// difference is that this method returns a Gauge and not a Metric so that no
+// must match those of the VariableLabels in Desc). If that label map is
-// type conversion is required.
+// accessed for the first time, a new Gauge is created. Implications of
-func (m *GaugeVec) GetMetricWith(labels Labels) (Gauge, error) {
+// creating a Gauge without using it and keeping the Gauge for later use are
-	metric, err := m.MetricVec.GetMetricWith(labels)
+// 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 (minus any curried labels).
+//
+// This method is used for the same purpose as
+// GetMetricWithLabelValues(...string). See there for pros and cons of the two
+// methods.
+func (v *GaugeVec) GetMetricWith(labels Labels) (Gauge, error) {
+	metric, err := v.metricVec.getMetricWith(labels)
 	if metric != nil {
 		return metric.(Gauge), err
 	}
@@ -101,18 +208,57 @@ func (m *GaugeVec) GetMetricWith(labels Labels) (Gauge, error) {
 }
 
 // WithLabelValues works as GetMetricWithLabelValues, but panics where
-// GetMetricWithLabelValues would have returned an error. By not returning an
+// GetMetricWithLabelValues would have returned an error. Not returning an
-// error, WithLabelValues allows shortcuts like
+// error allows shortcuts like
 //     myVec.WithLabelValues("404", "GET").Add(42)
-func (m *GaugeVec) WithLabelValues(lvs ...string) Gauge {
+func (v *GaugeVec) WithLabelValues(lvs ...string) Gauge {
-	return m.MetricVec.WithLabelValues(lvs...).(Gauge)
+	g, err := v.GetMetricWithLabelValues(lvs...)
+	if err != nil {
+		panic(err)
+	}
+	return g
 }
 
 // With works as GetMetricWith, but panics where GetMetricWithLabels would have
-// returned an error. By not returning an error, With allows shortcuts like
+// returned an error. Not returning an error allows shortcuts like
-//     myVec.With(Labels{"code": "404", "method": "GET"}).Add(42)
+//     myVec.With(prometheus.Labels{"code": "404", "method": "GET"}).Add(42)
-func (m *GaugeVec) With(labels Labels) Gauge {
+func (v *GaugeVec) With(labels Labels) Gauge {
-	return m.MetricVec.With(labels).(Gauge)
+	g, err := v.GetMetricWith(labels)
+	if err != nil {
+		panic(err)
+	}
+	return g
+}
+
+// CurryWith returns a vector curried with the provided labels, i.e. the
+// returned vector has those labels pre-set for all labeled operations performed
+// on it. The cardinality of the curried vector is reduced accordingly. The
+// order of the remaining labels stays the same (just with the curried labels
+// taken out of the sequence – which is relevant for the
+// (GetMetric)WithLabelValues methods). It is possible to curry a curried
+// vector, but only with labels not yet used for currying before.
+//
+// The metrics contained in the GaugeVec are shared between the curried and
+// uncurried vectors. They are just accessed differently. Curried and uncurried
+// vectors behave identically in terms of collection. Only one must be
+// registered with a given registry (usually the uncurried version). The Reset
+// method deletes all metrics, even if called on a curried vector.
+func (v *GaugeVec) CurryWith(labels Labels) (*GaugeVec, error) {
+	vec, err := v.curryWith(labels)
+	if vec != nil {
+		return &GaugeVec{vec}, err
+	}
+	return nil, err
+}
+
+// MustCurryWith works as CurryWith but panics where CurryWith would have
+// returned an error.
+func (v *GaugeVec) MustCurryWith(labels Labels) *GaugeVec {
+	vec, err := v.CurryWith(labels)
+	if err != nil {
+		panic(err)
+	}
+	return vec
 }
 
 // GaugeFunc is a Gauge whose value is determined at collect time by calling a

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

@@ -8,8 +8,10 @@ import (
 )
 
 type goCollector struct {
-	goroutines Gauge
+	goroutinesDesc *Desc
-	gcDesc     *Desc
+	threadsDesc    *Desc
+	gcDesc         *Desc
+	goInfoDesc     *Desc
 
 	// metrics to describe and collect
 	metrics memStatsMetrics
@@ -19,15 +21,22 @@ type goCollector struct {
 // go process.
 func NewGoCollector() Collector {
 	return &goCollector{
-		goroutines: NewGauge(GaugeOpts{
+		goroutinesDesc: NewDesc(
-			Namespace: "go",
+			"go_goroutines",
-			Name:      "goroutines",
+			"Number of goroutines that currently exist.",
-			Help:      "Number of goroutines that currently exist.",
+			nil, nil),
-		}),
+		threadsDesc: NewDesc(
+			"go_threads",
+			"Number of OS threads created.",
+			nil, nil),
 		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(
@@ -48,7 +57,7 @@ func NewGoCollector() Collector {
 			}, {
 				desc: NewDesc(
 					memstatNamespace("sys_bytes"),
-					"Number of bytes obtained by system. Sum of all system allocations.",
+					"Number of bytes obtained from system.",
 					nil, nil,
 				),
 				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.Sys) },
@@ -111,12 +120,12 @@ func NewGoCollector() Collector {
 				valType: GaugeValue,
 			}, {
 				desc: NewDesc(
-					memstatNamespace("heap_released_bytes_total"),
+					memstatNamespace("heap_released_bytes"),
-					"Total number of heap bytes released to OS.",
+					"Number of heap bytes released to OS.",
 					nil, nil,
 				),
 				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.HeapReleased) },
-				valType: CounterValue,
+				valType: GaugeValue,
 			}, {
 				desc: NewDesc(
 					memstatNamespace("heap_objects"),
@@ -213,6 +222,14 @@ 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,
 			},
 		},
 	}
@@ -224,9 +241,10 @@ func memstatNamespace(s string) string {
 
 // Describe returns all descriptions of the collector.
 func (c *goCollector) Describe(ch chan<- *Desc) {
-	ch <- c.goroutines.Desc()
+	ch <- c.goroutinesDesc
+	ch <- c.threadsDesc
 	ch <- c.gcDesc
-
+	ch <- c.goInfoDesc
 	for _, i := range c.metrics {
 		ch <- i.desc
 	}
@@ -234,8 +252,9 @@ 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) {
-	c.goroutines.Set(float64(runtime.NumGoroutine()))
+	ch <- MustNewConstMetric(c.goroutinesDesc, GaugeValue, float64(runtime.NumGoroutine()))
-	ch <- c.goroutines
+	n, _ := runtime.ThreadCreateProfile(nil)
+	ch <- MustNewConstMetric(c.threadsDesc, GaugeValue, float64(n))
 
 	var stats debug.GCStats
 	stats.PauseQuantiles = make([]time.Duration, 5)
@@ -248,6 +267,8 @@ 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

@@ -126,23 +126,16 @@ type HistogramOpts struct {
 	// string.
 	Help string
 
-	// ConstLabels are used to attach fixed labels to this
+	// ConstLabels are used to attach fixed labels to this metric. Metrics
-	// Histogram. Histograms with the same fully-qualified name must have the
+	// with the same fully-qualified name must have the same label names in
-	// same label names in their ConstLabels.
+	// their ConstLabels.
 	//
-	// Note that in most cases, labels have a value that varies during the
+	// ConstLabels are only used rarely. In particular, do not use them to
-	// lifetime of a process. Those labels are usually managed with a
+	// attach the same labels to all your metrics. Those use cases are
-	// HistogramVec. ConstLabels serve only special purposes. One is for the
+	// better covered by target labels set by the scraping Prometheus
-	// special case where the value of a label does not change during the
+	// server, or by one specific metric (e.g. a build_info or a
-	// lifetime of a process, e.g. if the revision of the running binary is
+	// machine_role metric). See also
-	// put into a label. Another, more advanced purpose is if more than one
+	// https://prometheus.io/docs/instrumenting/writing_exporters/#target-labels,-not-static-scraped-labels
-	// Collector needs to collect Histograms with the same fully-qualified
-	// name. In that case, those Summaries must differ in the values of
-	// their ConstLabels. See the Collector examples.
-	//
-	// If the value of a label never changes (not even between binaries),
-	// that label most likely should not be a label at all (but part of the
-	// metric name).
 	ConstLabels Labels
 
 	// Buckets defines the buckets into which observations are counted. Each
@@ -287,12 +280,11 @@ 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. At least one label name must be
+// partitioned by the given label names.
-// provided.
 func NewHistogramVec(opts HistogramOpts, labelNames []string) *HistogramVec {
 	desc := NewDesc(
 		BuildFQName(opts.Namespace, opts.Subsystem, opts.Name),
@@ -301,47 +293,116 @@ 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 replaces the method of the same name in
+// GetMetricWithLabelValues returns the Histogram for the given slice of label
-// MetricVec. The difference is that this method returns a Histogram and not a
+// values (same order as the VariableLabels in Desc). If that combination of
-// Metric so that no type conversion is required.
+// label values is accessed for the first time, a new Histogram is created.
-func (m *HistogramVec) GetMetricWithLabelValues(lvs ...string) (Histogram, error) {
+//
-	metric, err := m.MetricVec.GetMetricWithLabelValues(lvs...)
+// 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 (minus any curried labels).
+//
+// Note that for more than one label value, this method is prone to mistakes
+// caused by an incorrect order of arguments. Consider GetMetricWith(Labels) as
+// an alternative to avoid that type of mistake. For higher label numbers, the
+// latter has a much more readable (albeit more verbose) syntax, but it comes
+// with a performance overhead (for creating and processing the Labels map).
+// See also the GaugeVec example.
+func (v *HistogramVec) GetMetricWithLabelValues(lvs ...string) (Observer, error) {
+	metric, err := v.metricVec.getMetricWithLabelValues(lvs...)
 	if metric != nil {
-		return metric.(Histogram), err
+		return metric.(Observer), err
 	}
 	return nil, err
 }
 
-// GetMetricWith replaces the method of the same name in MetricVec. The
+// GetMetricWith returns the Histogram for the given Labels map (the label names
-// difference is that this method returns a Histogram and not a Metric so that no
+// must match those of the VariableLabels in Desc). If that label map is
-// type conversion is required.
+// accessed for the first time, a new Histogram is created. Implications of
-func (m *HistogramVec) GetMetricWith(labels Labels) (Histogram, error) {
+// creating a Histogram without using it and keeping the Histogram for later use
-	metric, err := m.MetricVec.GetMetricWith(labels)
+// 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 (minus any curried labels).
+//
+// This method is used for the same purpose as
+// GetMetricWithLabelValues(...string). See there for pros and cons of the two
+// methods.
+func (v *HistogramVec) GetMetricWith(labels Labels) (Observer, error) {
+	metric, err := v.metricVec.getMetricWith(labels)
 	if metric != nil {
-		return metric.(Histogram), err
+		return metric.(Observer), err
 	}
 	return nil, err
 }
 
 // WithLabelValues works as GetMetricWithLabelValues, but panics where
-// GetMetricWithLabelValues would have returned an error. By not returning an
+// GetMetricWithLabelValues would have returned an error. Not returning an
-// error, WithLabelValues allows shortcuts like
+// error allows shortcuts like
 //     myVec.WithLabelValues("404", "GET").Observe(42.21)
-func (m *HistogramVec) WithLabelValues(lvs ...string) Histogram {
+func (v *HistogramVec) WithLabelValues(lvs ...string) Observer {
-	return m.MetricVec.WithLabelValues(lvs...).(Histogram)
+	h, err := v.GetMetricWithLabelValues(lvs...)
+	if err != nil {
+		panic(err)
+	}
+	return h
 }
 
-// With works as GetMetricWith, but panics where GetMetricWithLabels would have
+// With works as GetMetricWith but panics where GetMetricWithLabels would have
-// returned an error. By not returning an error, With allows shortcuts like
+// returned an error. Not returning an error allows shortcuts like
-//     myVec.With(Labels{"code": "404", "method": "GET"}).Observe(42.21)
+//     myVec.With(prometheus.Labels{"code": "404", "method": "GET"}).Observe(42.21)
-func (m *HistogramVec) With(labels Labels) Histogram {
+func (v *HistogramVec) With(labels Labels) Observer {
-	return m.MetricVec.With(labels).(Histogram)
+	h, err := v.GetMetricWith(labels)
+	if err != nil {
+		panic(err)
+	}
+	return h
+}
+
+// CurryWith returns a vector curried with the provided labels, i.e. the
+// returned vector has those labels pre-set for all labeled operations performed
+// on it. The cardinality of the curried vector is reduced accordingly. The
+// order of the remaining labels stays the same (just with the curried labels
+// taken out of the sequence – which is relevant for the
+// (GetMetric)WithLabelValues methods). It is possible to curry a curried
+// vector, but only with labels not yet used for currying before.
+//
+// The metrics contained in the HistogramVec are shared between the curried and
+// uncurried vectors. They are just accessed differently. Curried and uncurried
+// vectors behave identically in terms of collection. Only one must be
+// registered with a given registry (usually the uncurried version). The Reset
+// method deletes all metrics, even if called on a curried vector.
+func (v *HistogramVec) CurryWith(labels Labels) (ObserverVec, error) {
+	vec, err := v.curryWith(labels)
+	if vec != nil {
+		return &HistogramVec{vec}, err
+	}
+	return nil, err
+}
+
+// MustCurryWith works as CurryWith but panics where CurryWith would have
+// returned an error.
+func (v *HistogramVec) MustCurryWith(labels Labels) ObserverVec {
+	vec, err := v.CurryWith(labels)
+	if err != nil {
+		panic(err)
+	}
+	return vec
 }
 
 type constHistogram struct {
@@ -401,8 +462,8 @@ func NewConstHistogram(
 	buckets map[float64]uint64,
 	labelValues ...string,
 ) (Metric, error) {
-	if len(desc.variableLabels) != len(labelValues) {
+	if err := validateLabelValues(labelValues, len(desc.variableLabels)); err != nil {
-		return nil, errInconsistentCardinality
+		return nil, err
 	}
 	return &constHistogram{
 		desc:       desc,

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

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

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

@@ -0,0 +1,57 @@
+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/metric.go

@@ -79,20 +79,12 @@ type Opts struct {
 	// with the same fully-qualified name must have the same label names in
 	// their ConstLabels.
 	//
-	// Note that in most cases, labels have a value that varies during the
+	// ConstLabels are only used rarely. In particular, do not use them to
-	// lifetime of a process. Those labels are usually managed with a metric
+	// attach the same labels to all your metrics. Those use cases are
-	// vector collector (like CounterVec, GaugeVec, UntypedVec). ConstLabels
+	// better covered by target labels set by the scraping Prometheus
-	// serve only special purposes. One is for the special case where the
+	// server, or by one specific metric (e.g. a build_info or a
-	// value of a label does not change during the lifetime of a process,
+	// machine_role metric). See also
-	// e.g. if the revision of the running binary is put into a
+	// https://prometheus.io/docs/instrumenting/writing_exporters/#target-labels,-not-static-scraped-labels
-	// label. Another, more advanced purpose is if more than one Collector
-	// needs to collect Metrics with the same fully-qualified name. In that
-	// case, those Metrics must differ in the values of their
-	// ConstLabels. See the Collector examples.
-	//
-	// If the value of a label never changes (not even between binaries),
-	// that label most likely should not be a label at all (but part of the
-	// metric name).
 	ConstLabels Labels
 }
 

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

@@ -0,0 +1,52 @@
+// 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
+	CurryWith(Labels) (ObserverVec, error)
+	MustCurryWith(Labels) ObserverVec
+
+	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        Counter
+	cpuTotal        *Desc
-	openFDs, maxFDs Gauge
+	openFDs, maxFDs *Desc
-	vsize, rss      Gauge
+	vsize, rss      *Desc
-	startTime       Gauge
+	startTime       *Desc
 }
 
 // NewProcessCollector returns a collector which exports the current state of
@@ -44,40 +44,45 @@ 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: NewCounter(CounterOpts{
+		cpuTotal: NewDesc(
-			Namespace: namespace,
+			ns+"process_cpu_seconds_total",
-			Name:      "process_cpu_seconds_total",
+			"Total user and system CPU time spent in seconds.",
-			Help:      "Total user and system CPU time spent in seconds.",
+			nil, nil,
-		}),
+		),
-		openFDs: NewGauge(GaugeOpts{
+		openFDs: NewDesc(
-			Namespace: namespace,
+			ns+"process_open_fds",
-			Name:      "process_open_fds",
+			"Number of open file descriptors.",
-			Help:      "Number of open file descriptors.",
+			nil, nil,
-		}),
+		),
-		maxFDs: NewGauge(GaugeOpts{
+		maxFDs: NewDesc(
-			Namespace: namespace,
+			ns+"process_max_fds",
-			Name:      "process_max_fds",
+			"Maximum number of open file descriptors.",
-			Help:      "Maximum number of open file descriptors.",
+			nil, nil,
-		}),
+		),
-		vsize: NewGauge(GaugeOpts{
+		vsize: NewDesc(
-			Namespace: namespace,
+			ns+"process_virtual_memory_bytes",
-			Name:      "process_virtual_memory_bytes",
+			"Virtual memory size in bytes.",
-			Help:      "Virtual memory size in bytes.",
+			nil, nil,
-		}),
+		),
-		rss: NewGauge(GaugeOpts{
+		rss: NewDesc(
-			Namespace: namespace,
+			ns+"process_resident_memory_bytes",
-			Name:      "process_resident_memory_bytes",
+			"Resident memory size in bytes.",
-			Help:      "Resident memory size in bytes.",
+			nil, nil,
-		}),
+		),
-		startTime: NewGauge(GaugeOpts{
+		startTime: NewDesc(
-			Namespace: namespace,
+			ns+"process_start_time_seconds",
-			Name:      "process_start_time_seconds",
+			"Start time of the process since unix epoch in seconds.",
-			Help:      "Start time of the process since unix epoch in seconds.",
+			nil, nil,
-		}),
+		),
 	}
 
 	// Set up process metric collection if supported by the runtime.
@@ -90,12 +95,12 @@ func NewProcessCollectorPIDFn(
 
 // Describe returns all descriptions of the collector.
 func (c *processCollector) Describe(ch chan<- *Desc) {
-	ch <- c.cpuTotal.Desc()
+	ch <- c.cpuTotal
-	ch <- c.openFDs.Desc()
+	ch <- c.openFDs
-	ch <- c.maxFDs.Desc()
+	ch <- c.maxFDs
-	ch <- c.vsize.Desc()
+	ch <- c.vsize
-	ch <- c.rss.Desc()
+	ch <- c.rss
-	ch <- c.startTime.Desc()
+	ch <- c.startTime
 }
 
 // Collect returns the current state of all metrics of the collector.
@@ -117,26 +122,19 @@ func (c *processCollector) processCollect(ch chan<- Metric) {
 	}
 
 	if stat, err := p.NewStat(); err == nil {
-		c.cpuTotal.Set(stat.CPUTime())
+		ch <- MustNewConstMetric(c.cpuTotal, CounterValue, stat.CPUTime())
-		ch <- c.cpuTotal
+		ch <- MustNewConstMetric(c.vsize, GaugeValue, float64(stat.VirtualMemory()))
-		c.vsize.Set(float64(stat.VirtualMemory()))
+		ch <- MustNewConstMetric(c.rss, GaugeValue, float64(stat.ResidentMemory()))
-		ch <- c.vsize
-		c.rss.Set(float64(stat.ResidentMemory()))
-		ch <- c.rss
-
 		if startTime, err := stat.StartTime(); err == nil {
-			c.startTime.Set(startTime)
+			ch <- MustNewConstMetric(c.startTime, GaugeValue, startTime)
-			ch <- c.startTime
 		}
 	}
 
 	if fds, err := p.FileDescriptorsLen(); err == nil {
-		c.openFDs.Set(float64(fds))
+		ch <- MustNewConstMetric(c.openFDs, GaugeValue, float64(fds))
-		ch <- c.openFDs
 	}
 
 	if limits, err := p.NewLimits(); err == nil {
-		c.maxFDs.Set(float64(limits.OpenFiles))
+		ch <- MustNewConstMetric(c.maxFDs, GaugeValue, float64(limits.OpenFiles))
-		ch <- c.maxFDs
 	}
 }

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

@@ -18,8 +18,10 @@ import (
 	"errors"
 	"fmt"
 	"os"
+	"runtime"
 	"sort"
 	"sync"
+	"unicode/utf8"
 
 	"github.com/golang/protobuf/proto"
 
@@ -80,7 +82,7 @@ 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 then the Registry type
+// Registerer as type for registration purposes (rather than the Registry type
 // directly). In that way, they are free to use custom Registerer implementation
 // (e.g. for testing purposes).
 type Registerer interface {
@@ -152,38 +154,6 @@ 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.
 //
@@ -201,25 +171,6 @@ 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
@@ -252,6 +203,13 @@ func (errs MultiError) Error() string {
 	return buf.String()
 }
 
+// Append appends the provided error if it is not nil.
+func (errs *MultiError) Append(err error) {
+	if err != nil {
+		*errs = append(*errs, err)
+	}
+}
+
 // MaybeUnwrap returns nil if len(errs) is 0. It returns the first and only
 // contained error as error if len(errs is 1). In all other cases, it returns
 // the MultiError directly. This is helpful for returning a MultiError in a way
@@ -294,7 +252,7 @@ func (r *Registry) Register(c Collector) error {
 	}()
 	r.mtx.Lock()
 	defer r.mtx.Unlock()
-	// Coduct various tests...
+	// Conduct various tests...
 	for desc := range descChan {
 
 		// Is the descriptor valid at all?
@@ -418,22 +376,12 @@ func (r *Registry) Gather() ([]*dto.MetricFamily, error) {
 	)
 
 	r.mtx.RLock()
+	goroutineBudget := len(r.collectorsByID)
 	metricFamiliesByName := make(map[string]*dto.MetricFamily, len(r.dimHashesByName))
-
+	collectors := make(chan Collector, len(r.collectorsByID))
-	// Scatter.
-	// (Collectors could be complex and slow, so we call them all at once.)
-	wg.Add(len(r.collectorsByID))
-	go func() {
-		wg.Wait()
-		close(metricChan)
-	}()
 	for _, collector := range r.collectorsByID {
-		go func(collector Collector) {
+		collectors <- collector
-			defer wg.Done()
-			collector.Collect(metricChan)
-		}(collector)
 	}
-
 	// In case pedantic checks are enabled, we have to copy the map before
 	// giving up the RLock.
 	if r.pedanticChecksEnabled {
@@ -442,129 +390,176 @@ func (r *Registry) Gather() ([]*dto.MetricFamily, error) {
 			registeredDescIDs[id] = struct{}{}
 		}
 	}
-
 	r.mtx.RUnlock()
 
+	wg.Add(goroutineBudget)
+
+	collectWorker := func() {
+		for {
+			select {
+			case collector := <-collectors:
+				collector.Collect(metricChan)
+				wg.Done()
+			default:
+				return
+			}
+		}
+	}
+
+	// Start the first worker now to make sure at least one is running.
+	go collectWorker()
+	goroutineBudget--
+
+	// Close the metricChan once all collectors are collected.
+	go func() {
+		wg.Wait()
+		close(metricChan)
+	}()
+
 	// Drain metricChan in case of premature return.
 	defer func() {
-		for _ = range metricChan {
+		for range metricChan {
 		}
 	}()
 
-	// Gather.
+collectLoop:
-	for metric := range metricChan {
+	for {
-		// This could be done concurrently, too, but it required locking
+		select {
-		// of metricFamiliesByName (and of metricHashes if checks are
+		case metric, ok := <-metricChan:
-		// enabled). Most likely not worth it.
+			if !ok {
-		desc := metric.Desc()
+				// metricChan is closed, we are done.
-		dtoMetric := &dto.Metric{}
+				break collectLoop
-		if err := metric.Write(dtoMetric); err != nil {
+			}
-			errs = append(errs, fmt.Errorf(
+			errs.Append(processMetric(
-				"error collecting metric %v: %s", desc, err,
+				metric, metricFamiliesByName,
+				metricHashes, dimHashes,
+				registeredDescIDs,
 			))
-			continue
+		default:
+			if goroutineBudget <= 0 || len(collectors) == 0 {
+				// All collectors are aleady being worked on or
+				// we have already as many goroutines started as
+				// there are collectors. Just process metrics
+				// from now on.
+				for metric := range metricChan {
+					errs.Append(processMetric(
+						metric, metricFamiliesByName,
+						metricHashes, dimHashes,
+						registeredDescIDs,
+					))
+				}
+				break collectLoop
+			}
+			// Start more workers.
+			go collectWorker()
+			goroutineBudget--
+			runtime.Gosched()
 		}
-		metricFamily, ok := metricFamiliesByName[desc.fqName]
-		if ok {
-			if metricFamily.GetHelp() != desc.help {
-				errs = append(errs, fmt.Errorf(
-					"collected metric %s %s has help %q but should have %q",
-					desc.fqName, dtoMetric, desc.help, metricFamily.GetHelp(),
-				))
-				continue
-			}
-			// TODO(beorn7): Simplify switch once Desc has type.
-			switch metricFamily.GetType() {
-			case dto.MetricType_COUNTER:
-				if dtoMetric.Counter == nil {
-					errs = append(errs, fmt.Errorf(
-						"collected metric %s %s should be a Counter",
-						desc.fqName, dtoMetric,
-					))
-					continue
-				}
-			case dto.MetricType_GAUGE:
-				if dtoMetric.Gauge == nil {
-					errs = append(errs, fmt.Errorf(
-						"collected metric %s %s should be a Gauge",
-						desc.fqName, dtoMetric,
-					))
-					continue
-				}
-			case dto.MetricType_SUMMARY:
-				if dtoMetric.Summary == nil {
-					errs = append(errs, fmt.Errorf(
-						"collected metric %s %s should be a Summary",
-						desc.fqName, dtoMetric,
-					))
-					continue
-				}
-			case dto.MetricType_UNTYPED:
-				if dtoMetric.Untyped == nil {
-					errs = append(errs, fmt.Errorf(
-						"collected metric %s %s should be Untyped",
-						desc.fqName, dtoMetric,
-					))
-					continue
-				}
-			case dto.MetricType_HISTOGRAM:
-				if dtoMetric.Histogram == nil {
-					errs = append(errs, fmt.Errorf(
-						"collected metric %s %s should be a Histogram",
-						desc.fqName, dtoMetric,
-					))
-					continue
-				}
-			default:
-				panic("encountered MetricFamily with invalid type")
-			}
-		} else {
-			metricFamily = &dto.MetricFamily{}
-			metricFamily.Name = proto.String(desc.fqName)
-			metricFamily.Help = proto.String(desc.help)
-			// TODO(beorn7): Simplify switch once Desc has type.
-			switch {
-			case dtoMetric.Gauge != nil:
-				metricFamily.Type = dto.MetricType_GAUGE.Enum()
-			case dtoMetric.Counter != nil:
-				metricFamily.Type = dto.MetricType_COUNTER.Enum()
-			case dtoMetric.Summary != nil:
-				metricFamily.Type = dto.MetricType_SUMMARY.Enum()
-			case dtoMetric.Untyped != nil:
-				metricFamily.Type = dto.MetricType_UNTYPED.Enum()
-			case dtoMetric.Histogram != nil:
-				metricFamily.Type = dto.MetricType_HISTOGRAM.Enum()
-			default:
-				errs = append(errs, fmt.Errorf(
-					"empty metric collected: %s", dtoMetric,
-				))
-				continue
-			}
-			metricFamiliesByName[desc.fqName] = metricFamily
-		}
-		if err := checkMetricConsistency(metricFamily, dtoMetric, metricHashes, dimHashes); err != nil {
-			errs = append(errs, err)
-			continue
-		}
-		if r.pedanticChecksEnabled {
-			// Is the desc registered at all?
-			if _, exist := registeredDescIDs[desc.id]; !exist {
-				errs = append(errs, fmt.Errorf(
-					"collected metric %s %s with unregistered descriptor %s",
-					metricFamily.GetName(), dtoMetric, desc,
-				))
-				continue
-			}
-			if err := checkDescConsistency(metricFamily, dtoMetric, desc); err != nil {
-				errs = append(errs, err)
-				continue
-			}
-		}
-		metricFamily.Metric = append(metricFamily.Metric, dtoMetric)
 	}
 	return normalizeMetricFamilies(metricFamiliesByName), errs.MaybeUnwrap()
 }
 
+// processMetric is an internal helper method only used by the Gather method.
+func processMetric(
+	metric Metric,
+	metricFamiliesByName map[string]*dto.MetricFamily,
+	metricHashes map[uint64]struct{},
+	dimHashes map[string]uint64,
+	registeredDescIDs map[uint64]struct{},
+) error {
+	desc := metric.Desc()
+	dtoMetric := &dto.Metric{}
+	if err := metric.Write(dtoMetric); err != nil {
+		return fmt.Errorf("error collecting metric %v: %s", desc, err)
+	}
+	metricFamily, ok := metricFamiliesByName[desc.fqName]
+	if ok {
+		if metricFamily.GetHelp() != desc.help {
+			return fmt.Errorf(
+				"collected metric %s %s has help %q but should have %q",
+				desc.fqName, dtoMetric, desc.help, metricFamily.GetHelp(),
+			)
+		}
+		// TODO(beorn7): Simplify switch once Desc has type.
+		switch metricFamily.GetType() {
+		case dto.MetricType_COUNTER:
+			if dtoMetric.Counter == nil {
+				return fmt.Errorf(
+					"collected metric %s %s should be a Counter",
+					desc.fqName, dtoMetric,
+				)
+			}
+		case dto.MetricType_GAUGE:
+			if dtoMetric.Gauge == nil {
+				return fmt.Errorf(
+					"collected metric %s %s should be a Gauge",
+					desc.fqName, dtoMetric,
+				)
+			}
+		case dto.MetricType_SUMMARY:
+			if dtoMetric.Summary == nil {
+				return fmt.Errorf(
+					"collected metric %s %s should be a Summary",
+					desc.fqName, dtoMetric,
+				)
+			}
+		case dto.MetricType_UNTYPED:
+			if dtoMetric.Untyped == nil {
+				return fmt.Errorf(
+					"collected metric %s %s should be Untyped",
+					desc.fqName, dtoMetric,
+				)
+			}
+		case dto.MetricType_HISTOGRAM:
+			if dtoMetric.Histogram == nil {
+				return fmt.Errorf(
+					"collected metric %s %s should be a Histogram",
+					desc.fqName, dtoMetric,
+				)
+			}
+		default:
+			panic("encountered MetricFamily with invalid type")
+		}
+	} else {
+		metricFamily = &dto.MetricFamily{}
+		metricFamily.Name = proto.String(desc.fqName)
+		metricFamily.Help = proto.String(desc.help)
+		// TODO(beorn7): Simplify switch once Desc has type.
+		switch {
+		case dtoMetric.Gauge != nil:
+			metricFamily.Type = dto.MetricType_GAUGE.Enum()
+		case dtoMetric.Counter != nil:
+			metricFamily.Type = dto.MetricType_COUNTER.Enum()
+		case dtoMetric.Summary != nil:
+			metricFamily.Type = dto.MetricType_SUMMARY.Enum()
+		case dtoMetric.Untyped != nil:
+			metricFamily.Type = dto.MetricType_UNTYPED.Enum()
+		case dtoMetric.Histogram != nil:
+			metricFamily.Type = dto.MetricType_HISTOGRAM.Enum()
+		default:
+			return fmt.Errorf("empty metric collected: %s", dtoMetric)
+		}
+		metricFamiliesByName[desc.fqName] = metricFamily
+	}
+	if err := checkMetricConsistency(metricFamily, dtoMetric, metricHashes, dimHashes); err != nil {
+		return err
+	}
+	if registeredDescIDs != nil {
+		// Is the desc registered at all?
+		if _, exist := registeredDescIDs[desc.id]; !exist {
+			return fmt.Errorf(
+				"collected metric %s %s with unregistered descriptor %s",
+				metricFamily.GetName(), dtoMetric, desc,
+			)
+		}
+		if err := checkDescConsistency(metricFamily, dtoMetric, desc); err != nil {
+			return err
+		}
+	}
+	metricFamily.Metric = append(metricFamily.Metric, dtoMetric)
+	return nil
+}
+
 // Gatherers is a slice of Gatherer instances that implements the Gatherer
 // interface itself. Its Gather method calls Gather on all Gatherers in the
 // slice in order and returns the merged results. Errors returned from the
@@ -683,7 +678,7 @@ func (s metricSorter) Less(i, j int) bool {
 	return s[i].GetTimestampMs() < s[j].GetTimestampMs()
 }
 
-// normalizeMetricFamilies returns a MetricFamily slice whith empty
+// normalizeMetricFamilies returns a MetricFamily slice with 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 {
@@ -706,7 +701,7 @@ 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 alread in the provided metricHashes, an error
+// name. If the resulting hash is already in the provided metricHashes, an error
 // is returned. If not, it is added to metricHashes. The provided dimHashes maps
 // MetricFamily names to their dimHash (hashed sorted label names). If dimHashes
 // doesn't yet contain a hash for the provided MetricFamily, it is
@@ -730,6 +725,12 @@ 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

@@ -36,7 +36,10 @@ 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.
+// 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.
 //
 // 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
@@ -54,6 +57,9 @@ 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}
 
@@ -75,8 +81,10 @@ const (
 )
 
 // SummaryOpts bundles the options for creating a Summary metric. It is
-// mandatory to set Name and Help to a non-empty string. All other fields are
+// mandatory to set Name and Help to a non-empty string. While all other fields
-// optional and can safely be left at their zero value.
+// 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.
 type SummaryOpts struct {
 	// Namespace, Subsystem, and Name are components of the fully-qualified
 	// name of the Summary (created by joining these components with
@@ -93,29 +101,28 @@ type SummaryOpts struct {
 	// string.
 	Help string
 
-	// ConstLabels are used to attach fixed labels to this
+	// ConstLabels are used to attach fixed labels to this metric. Metrics
-	// Summary. Summaries with the same fully-qualified name must have the
+	// with the same fully-qualified name must have the same label names in
-	// same label names in their ConstLabels.
+	// their ConstLabels.
 	//
-	// Note that in most cases, labels have a value that varies during the
+	// ConstLabels are only used rarely. In particular, do not use them to
-	// lifetime of a process. Those labels are usually managed with a
+	// attach the same labels to all your metrics. Those use cases are
-	// SummaryVec. ConstLabels serve only special purposes. One is for the
+	// better covered by target labels set by the scraping Prometheus
-	// special case where the value of a label does not change during the
+	// server, or by one specific metric (e.g. a build_info or a
-	// lifetime of a process, e.g. if the revision of the running binary is
+	// machine_role metric). See also
-	// put into a label. Another, more advanced purpose is if more than one
+	// https://prometheus.io/docs/instrumenting/writing_exporters/#target-labels,-not-static-scraped-labels
-	// Collector needs to collect Summaries with the same fully-qualified
-	// name. In that case, those Summaries must differ in the values of
-	// their ConstLabels. See the Collector examples.
-	//
-	// If the value of a label never changes (not even between binaries),
-	// that label most likely should not be a label at all (but part of the
-	// metric name).
 	ConstLabels Labels
 
 	// Objectives defines the quantile rank estimates with their respective
-	// absolute error. If Objectives[q] = e, then the value reported
+	// absolute error. If Objectives[q] = e, then the value reported for q
-	// for q will be the φ-quantile value for some φ between q-e and q+e.
+	// will be the φ-quantile value for some φ between q-e and q+e.  The
-	// The default value is DefObjectives.
+	// 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.
 	Objectives map[float64]float64
 
 	// MaxAge defines the duration for which an observation stays relevant
@@ -183,7 +190,7 @@ func newSummary(desc *Desc, opts SummaryOpts, labelValues ...string) Summary {
 		}
 	}
 
-	if len(opts.Objectives) == 0 {
+	if opts.Objectives == nil {
 		opts.Objectives = DefObjectives
 	}
 
@@ -390,12 +397,11 @@ 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. At least one label name must be
+// partitioned by the given label names.
-// provided.
 func NewSummaryVec(opts SummaryOpts, labelNames []string) *SummaryVec {
 	desc := NewDesc(
 		BuildFQName(opts.Namespace, opts.Subsystem, opts.Name),
@@ -404,47 +410,116 @@ 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 replaces the method of the same name in
+// GetMetricWithLabelValues returns the Summary for the given slice of label
-// MetricVec. The difference is that this method returns a Summary and not a
+// values (same order as the VariableLabels in Desc). If that combination of
-// Metric so that no type conversion is required.
+// label values is accessed for the first time, a new Summary is created.
-func (m *SummaryVec) GetMetricWithLabelValues(lvs ...string) (Summary, error) {
+//
-	metric, err := m.MetricVec.GetMetricWithLabelValues(lvs...)
+// 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 (minus any curried labels).
+//
+// Note that for more than one label value, this method is prone to mistakes
+// caused by an incorrect order of arguments. Consider GetMetricWith(Labels) as
+// an alternative to avoid that type of mistake. For higher label numbers, the
+// latter has a much more readable (albeit more verbose) syntax, but it comes
+// with a performance overhead (for creating and processing the Labels map).
+// See also the GaugeVec example.
+func (v *SummaryVec) GetMetricWithLabelValues(lvs ...string) (Observer, error) {
+	metric, err := v.metricVec.getMetricWithLabelValues(lvs...)
 	if metric != nil {
-		return metric.(Summary), err
+		return metric.(Observer), err
 	}
 	return nil, err
 }
 
-// GetMetricWith replaces the method of the same name in MetricVec. The
+// GetMetricWith returns the Summary for the given Labels map (the label names
-// difference is that this method returns a Summary and not a Metric so that no
+// must match those of the VariableLabels in Desc). If that label map is
-// type conversion is required.
+// accessed for the first time, a new Summary is created. Implications of
-func (m *SummaryVec) GetMetricWith(labels Labels) (Summary, error) {
+// creating a Summary without using it and keeping the Summary for later use are
-	metric, err := m.MetricVec.GetMetricWith(labels)
+// 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 (minus any curried labels).
+//
+// This method is used for the same purpose as
+// GetMetricWithLabelValues(...string). See there for pros and cons of the two
+// methods.
+func (v *SummaryVec) GetMetricWith(labels Labels) (Observer, error) {
+	metric, err := v.metricVec.getMetricWith(labels)
 	if metric != nil {
-		return metric.(Summary), err
+		return metric.(Observer), err
 	}
 	return nil, err
 }
 
 // WithLabelValues works as GetMetricWithLabelValues, but panics where
-// GetMetricWithLabelValues would have returned an error. By not returning an
+// GetMetricWithLabelValues would have returned an error. Not returning an
-// error, WithLabelValues allows shortcuts like
+// error allows shortcuts like
 //     myVec.WithLabelValues("404", "GET").Observe(42.21)
-func (m *SummaryVec) WithLabelValues(lvs ...string) Summary {
+func (v *SummaryVec) WithLabelValues(lvs ...string) Observer {
-	return m.MetricVec.WithLabelValues(lvs...).(Summary)
+	s, err := v.GetMetricWithLabelValues(lvs...)
+	if err != nil {
+		panic(err)
+	}
+	return s
 }
 
 // With works as GetMetricWith, but panics where GetMetricWithLabels would have
-// returned an error. By not returning an error, With allows shortcuts like
+// returned an error. Not returning an error allows shortcuts like
-//     myVec.With(Labels{"code": "404", "method": "GET"}).Observe(42.21)
+//     myVec.With(prometheus.Labels{"code": "404", "method": "GET"}).Observe(42.21)
-func (m *SummaryVec) With(labels Labels) Summary {
+func (v *SummaryVec) With(labels Labels) Observer {
-	return m.MetricVec.With(labels).(Summary)
+	s, err := v.GetMetricWith(labels)
+	if err != nil {
+		panic(err)
+	}
+	return s
+}
+
+// CurryWith returns a vector curried with the provided labels, i.e. the
+// returned vector has those labels pre-set for all labeled operations performed
+// on it. The cardinality of the curried vector is reduced accordingly. The
+// order of the remaining labels stays the same (just with the curried labels
+// taken out of the sequence – which is relevant for the
+// (GetMetric)WithLabelValues methods). It is possible to curry a curried
+// vector, but only with labels not yet used for currying before.
+//
+// The metrics contained in the SummaryVec are shared between the curried and
+// uncurried vectors. They are just accessed differently. Curried and uncurried
+// vectors behave identically in terms of collection. Only one must be
+// registered with a given registry (usually the uncurried version). The Reset
+// method deletes all metrics, even if called on a curried vector.
+func (v *SummaryVec) CurryWith(labels Labels) (ObserverVec, error) {
+	vec, err := v.curryWith(labels)
+	if vec != nil {
+		return &SummaryVec{vec}, err
+	}
+	return nil, err
+}
+
+// MustCurryWith works as CurryWith but panics where CurryWith would have
+// returned an error.
+func (v *SummaryVec) MustCurryWith(labels Labels) ObserverVec {
+	vec, err := v.CurryWith(labels)
+	if err != nil {
+		panic(err)
+	}
+	return vec
 }
 
 type constSummary struct {
@@ -505,8 +580,8 @@ func NewConstSummary(
 	quantiles map[float64]float64,
 	labelValues ...string,
 ) (Metric, error) {
-	if len(desc.variableLabels) != len(labelValues) {
+	if err := validateLabelValues(labelValues, len(desc.variableLabels)); err != nil {
-		return nil, errInconsistentCardinality
+		return nil, err
 	}
 	return &constSummary{
 		desc:       desc,

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

@@ -0,0 +1,51 @@
+// 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

@@ -13,108 +13,12 @@
 
 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
 
-// NewUntyped creates a new Untyped metric from the provided UntypedOpts.
+// UntypedFunc works like GaugeFunc but the collected metric is of type
-func NewUntyped(opts UntypedOpts) Untyped {
+// "Untyped". UntypedFunc is useful to mirror an external metric of unknown
-	return newValue(NewDesc(
+// type.
-		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 +14,8 @@
 package prometheus
 
 import (
-	"errors"
 	"fmt"
-	"math"
 	"sort"
-	"sync/atomic"
 
 	dto "github.com/prometheus/client_model/go"
 
@@ -36,77 +33,6 @@ 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 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
-
-	selfCollector
-
-	desc       *Desc
-	valType    ValueType
-	labelPairs []*dto.LabelPair
-}
-
-// newValue returns a newly allocated value with the given Desc, ValueType,
-// sample value and label values. It panics if the number of label
-// values is different from the number of variable labels in Desc.
-func newValue(desc *Desc, valueType ValueType, val float64, labelValues ...string) *value {
-	if len(labelValues) != len(desc.variableLabels) {
-		panic(errInconsistentCardinality)
-	}
-	result := &value{
-		desc:       desc,
-		valType:    valueType,
-		valBits:    math.Float64bits(val),
-		labelPairs: makeLabelPairs(desc, labelValues),
-	}
-	result.init(result)
-	return result
-}
-
-func (v *value) Desc() *Desc {
-	return v.desc
-}
-
-func (v *value) Set(val float64) {
-	atomic.StoreUint64(&v.valBits, math.Float64bits(val))
-}
-
-func (v *value) Inc() {
-	v.Add(1)
-}
-
-func (v *value) Dec() {
-	v.Add(-1)
-}
-
-func (v *value) Add(val float64) {
-	for {
-		oldBits := atomic.LoadUint64(&v.valBits)
-		newBits := math.Float64bits(math.Float64frombits(oldBits) + val)
-		if atomic.CompareAndSwapUint64(&v.valBits, oldBits, newBits) {
-			return
-		}
-	}
-}
-
-func (v *value) Sub(val float64) {
-	v.Add(val * -1)
-}
-
-func (v *value) Write(out *dto.Metric) error {
-	val := math.Float64frombits(atomic.LoadUint64(&v.valBits))
-	return populateMetric(v.valType, val, v.labelPairs, out)
-}
-
 // valueFunc is a generic metric for simple values retrieved on collect time
 // from a function. It implements Metric and Collector. Its effective type is
 // determined by ValueType. This is a low-level building block used by the
@@ -153,8 +79,8 @@ 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 len(desc.variableLabels) != len(labelValues) {
+	if err := validateLabelValues(labelValues, len(desc.variableLabels)); err != nil {
-		return nil, errInconsistentCardinality
+		return nil, err
 	}
 	return &constMetric{
 		desc:       desc,

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

@@ -20,33 +20,180 @@ import (
 	"github.com/prometheus/common/model"
 )
 
-// MetricVec is a Collector to bundle metrics of the same name that
+// metricVec is a Collector to bundle metrics of the same name that differ in
-// differ in their label values. MetricVec is usually not used directly but as a
+// their label values. metricVec is not used directly (and therefore
-// building block for implementations of vectors of a given metric
+// unexported). It is used as a building block for implementations of vectors of
-// type. GaugeVec, CounterVec, SummaryVec, and UntypedVec are examples already
+// a given metric type, like GaugeVec, CounterVec, SummaryVec, and HistogramVec.
-// provided in this package.
+// It also handles label currying. It uses basicMetricVec internally.
-type MetricVec struct {
+type metricVec struct {
-	mtx      sync.RWMutex // Protects the children.
+	*metricMap
-	children map[uint64][]metricWithLabelValues
-	desc     *Desc
 
-	newMetric   func(labelValues ...string) Metric
+	curry []curriedLabelValue
-	hashAdd     func(h uint64, s string) uint64 // replace hash function for testing collision handling
+
+	// hashAdd and hashAddByte can be replaced for testing collision handling.
+	hashAdd     func(h uint64, s string) uint64
 	hashAddByte func(h uint64, b byte) uint64
 }
 
-// newMetricVec returns an initialized MetricVec. The concrete value is
+// newMetricVec returns an initialized metricVec.
-// returned for embedding into another struct.
+func newMetricVec(desc *Desc, newMetric func(lvs ...string) Metric) *metricVec {
-func newMetricVec(desc *Desc, newMetric func(lvs ...string) Metric) *MetricVec {
+	return &metricVec{
-	return &MetricVec{
+		metricMap: &metricMap{
-		children:    map[uint64][]metricWithLabelValues{},
+			metrics:   map[uint64][]metricWithLabelValues{},
-		desc:        desc,
+			desc:      desc,
-		newMetric:   newMetric,
+			newMetric: newMetric,
+		},
 		hashAdd:     hashAdd,
 		hashAddByte: hashAddByte,
 	}
 }
 
+// DeleteLabelValues removes the metric where the variable labels are the same
+// as those passed in as labels (same order as the VariableLabels in Desc). It
+// returns true if a metric was deleted.
+//
+// It is not an error if the number of label values is not the same as the
+// number of VariableLabels in Desc. However, such inconsistent label count can
+// never match an actual metric, so the method will always return false in that
+// case.
+//
+// Note that for more than one label value, this method is prone to mistakes
+// caused by an incorrect order of arguments. Consider Delete(Labels) as an
+// alternative to avoid that type of mistake. For higher label numbers, the
+// latter has a much more readable (albeit more verbose) syntax, but it comes
+// with a performance overhead (for creating and processing the Labels map).
+// See also the CounterVec example.
+func (m *metricVec) DeleteLabelValues(lvs ...string) bool {
+	h, err := m.hashLabelValues(lvs)
+	if err != nil {
+		return false
+	}
+
+	return m.metricMap.deleteByHashWithLabelValues(h, lvs, m.curry)
+}
+
+// Delete deletes the metric where the variable labels are the same as those
+// passed in as labels. It returns true if a metric was deleted.
+//
+// It is not an error if the number and names of the Labels are inconsistent
+// with those of the VariableLabels in Desc. However, such inconsistent Labels
+// can never match an actual metric, so the method will always return false in
+// that case.
+//
+// This method is used for the same purpose as DeleteLabelValues(...string). See
+// there for pros and cons of the two methods.
+func (m *metricVec) Delete(labels Labels) bool {
+	h, err := m.hashLabels(labels)
+	if err != nil {
+		return false
+	}
+
+	return m.metricMap.deleteByHashWithLabels(h, labels, m.curry)
+}
+
+func (m *metricVec) curryWith(labels Labels) (*metricVec, error) {
+	var (
+		newCurry []curriedLabelValue
+		oldCurry = m.curry
+		iCurry   int
+	)
+	for i, label := range m.desc.variableLabels {
+		val, ok := labels[label]
+		if iCurry < len(oldCurry) && oldCurry[iCurry].index == i {
+			if ok {
+				return nil, fmt.Errorf("label name %q is already curried", label)
+			}
+			newCurry = append(newCurry, oldCurry[iCurry])
+			iCurry++
+		} else {
+			if !ok {
+				continue // Label stays uncurried.
+			}
+			newCurry = append(newCurry, curriedLabelValue{i, val})
+		}
+	}
+	if l := len(oldCurry) + len(labels) - len(newCurry); l > 0 {
+		return nil, fmt.Errorf("%d unknown label(s) found during currying", l)
+	}
+
+	return &metricVec{
+		metricMap:   m.metricMap,
+		curry:       newCurry,
+		hashAdd:     m.hashAdd,
+		hashAddByte: m.hashAddByte,
+	}, nil
+}
+
+func (m *metricVec) getMetricWithLabelValues(lvs ...string) (Metric, error) {
+	h, err := m.hashLabelValues(lvs)
+	if err != nil {
+		return nil, err
+	}
+
+	return m.metricMap.getOrCreateMetricWithLabelValues(h, lvs, m.curry), nil
+}
+
+func (m *metricVec) getMetricWith(labels Labels) (Metric, error) {
+	h, err := m.hashLabels(labels)
+	if err != nil {
+		return nil, err
+	}
+
+	return m.metricMap.getOrCreateMetricWithLabels(h, labels, m.curry), nil
+}
+
+func (m *metricVec) hashLabelValues(vals []string) (uint64, error) {
+	if err := validateLabelValues(vals, len(m.desc.variableLabels)-len(m.curry)); err != nil {
+		return 0, err
+	}
+
+	var (
+		h             = hashNew()
+		curry         = m.curry
+		iVals, iCurry int
+	)
+	for i := 0; i < len(m.desc.variableLabels); i++ {
+		if iCurry < len(curry) && curry[iCurry].index == i {
+			h = m.hashAdd(h, curry[iCurry].value)
+			iCurry++
+		} else {
+			h = m.hashAdd(h, vals[iVals])
+			iVals++
+		}
+		h = m.hashAddByte(h, model.SeparatorByte)
+	}
+	return h, nil
+}
+
+func (m *metricVec) hashLabels(labels Labels) (uint64, error) {
+	if err := validateValuesInLabels(labels, len(m.desc.variableLabels)-len(m.curry)); err != nil {
+		return 0, err
+	}
+
+	var (
+		h      = hashNew()
+		curry  = m.curry
+		iCurry int
+	)
+	for i, label := range m.desc.variableLabels {
+		val, ok := labels[label]
+		if iCurry < len(curry) && curry[iCurry].index == i {
+			if ok {
+				return 0, fmt.Errorf("label name %q is already curried", label)
+			}
+			h = m.hashAdd(h, curry[iCurry].value)
+			iCurry++
+		} else {
+			if !ok {
+				return 0, fmt.Errorf("label name %q missing in label map", label)
+			}
+			h = m.hashAdd(h, val)
+		}
+		h = m.hashAddByte(h, model.SeparatorByte)
+	}
+	return h, nil
+}
+
 // metricWithLabelValues provides the metric and its label values for
 // disambiguation on hash collision.
 type metricWithLabelValues struct {
@@ -54,166 +201,72 @@ type metricWithLabelValues struct {
 	metric Metric
 }
 
-// Describe implements Collector. The length of the returned slice
+// curriedLabelValue sets the curried value for a label at the given index.
-// is always one.
+type curriedLabelValue struct {
-func (m *MetricVec) Describe(ch chan<- *Desc) {
+	index int
+	value string
+}
+
+// metricMap is a helper for metricVec and shared between differently curried
+// metricVecs.
+type metricMap struct {
+	mtx       sync.RWMutex // Protects metrics.
+	metrics   map[uint64][]metricWithLabelValues
+	desc      *Desc
+	newMetric func(labelValues ...string) Metric
+}
+
+// Describe implements Collector. It will send exactly one Desc to the provided
+// channel.
+func (m *metricMap) Describe(ch chan<- *Desc) {
 	ch <- m.desc
 }
 
 // Collect implements Collector.
-func (m *MetricVec) Collect(ch chan<- Metric) {
+func (m *metricMap) Collect(ch chan<- Metric) {
 	m.mtx.RLock()
 	defer m.mtx.RUnlock()
 
-	for _, metrics := range m.children {
+	for _, metrics := range m.metrics {
 		for _, metric := range metrics {
 			ch <- metric.metric
 		}
 	}
 }
 
-// GetMetricWithLabelValues returns the Metric for the given slice of label
+// Reset deletes all metrics in this vector.
-// values (same order as the VariableLabels in Desc). If that combination of
+func (m *metricMap) Reset() {
-// 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
-	}
-
-	return m.getOrCreateMetricWithLabelValues(h, lvs), nil
-}
-
-// GetMetricWith returns the Metric for the given Labels map (the label names
-// must match those of the VariableLabels in Desc). If that label map is
-// accessed for the first time, a new Metric is created. Implications of
-// creating a Metric without using it and keeping the Metric for later use are
-// the same as for GetMetricWithLabelValues.
-//
-// An error is returned if the number and names of the Labels are inconsistent
-// with those of the VariableLabels in Desc.
-//
-// This method is used for the same purpose as
-// GetMetricWithLabelValues(...string). See there for pros and cons of the two
-// methods.
-func (m *MetricVec) GetMetricWith(labels Labels) (Metric, error) {
-	h, err := m.hashLabels(labels)
-	if err != nil {
-		return nil, err
-	}
-
-	return m.getOrCreateMetricWithLabels(h, labels), nil
-}
-
-// WithLabelValues works as GetMetricWithLabelValues, but panics if an error
-// occurs. The method allows neat syntax like:
-//     httpReqs.WithLabelValues("404", "POST").Inc()
-func (m *MetricVec) WithLabelValues(lvs ...string) Metric {
-	metric, err := m.GetMetricWithLabelValues(lvs...)
-	if err != nil {
-		panic(err)
-	}
-	return metric
-}
-
-// With works as GetMetricWith, but panics if an error occurs. The method allows
-// neat syntax like:
-//     httpReqs.With(Labels{"status":"404", "method":"POST"}).Inc()
-func (m *MetricVec) With(labels Labels) Metric {
-	metric, err := m.GetMetricWith(labels)
-	if err != nil {
-		panic(err)
-	}
-	return metric
-}
-
-// DeleteLabelValues removes the metric where the variable labels are the same
-// as those passed in as labels (same order as the VariableLabels in Desc). It
-// returns true if a metric was deleted.
-//
-// It is not an error if the number of label values is not the same as the
-// number of VariableLabels in Desc.  However, such inconsistent label count can
-// never match an actual Metric, so the method will always return false in that
-// case.
-//
-// Note that for more than one label value, this method is prone to mistakes
-// caused by an incorrect order of arguments. Consider Delete(Labels) as an
-// alternative to avoid that type of mistake. For higher label numbers, the
-// latter has a much more readable (albeit more verbose) syntax, but it comes
-// with a performance overhead (for creating and processing the Labels map).
-// See also the CounterVec example.
-func (m *MetricVec) DeleteLabelValues(lvs ...string) bool {
 	m.mtx.Lock()
 	defer m.mtx.Unlock()
 
-	h, err := m.hashLabelValues(lvs)
+	for h := range m.metrics {
-	if err != nil {
+		delete(m.metrics, h)
-		return false
 	}
-	return m.deleteByHashWithLabelValues(h, lvs)
-}
-
-// Delete deletes the metric where the variable labels are the same as those
-// passed in as labels. It returns true if a metric was deleted.
-//
-// It is not an error if the number and names of the Labels are inconsistent
-// with those of the VariableLabels in 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 {
-	m.mtx.Lock()
-	defer m.mtx.Unlock()
-
-	h, err := m.hashLabels(labels)
-	if err != nil {
-		return false
-	}
-
-	return m.deleteByHashWithLabels(h, labels)
 }
 
 // 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 *metricMap) deleteByHashWithLabelValues(
-	metrics, ok := m.children[h]
+	h uint64, lvs []string, curry []curriedLabelValue,
+) bool {
+	m.mtx.Lock()
+	defer m.mtx.Unlock()
+
+	metrics, ok := m.metrics[h]
 	if !ok {
 		return false
 	}
 
-	i := m.findMetricWithLabelValues(metrics, lvs)
+	i := findMetricWithLabelValues(metrics, lvs, curry)
 	if i >= len(metrics) {
 		return false
 	}
 
 	if len(metrics) > 1 {
-		m.children[h] = append(metrics[:i], metrics[i+1:]...)
+		m.metrics[h] = append(metrics[:i], metrics[i+1:]...)
 	} else {
-		delete(m.children, h)
+		delete(m.metrics, h)
 	}
 	return true
 }
@@ -221,69 +274,35 @@ 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 *metricMap) deleteByHashWithLabels(
-	metrics, ok := m.children[h]
+	h uint64, labels Labels, curry []curriedLabelValue,
+) bool {
+	metrics, ok := m.metrics[h]
 	if !ok {
 		return false
 	}
-	i := m.findMetricWithLabels(metrics, labels)
+	i := findMetricWithLabels(m.desc, metrics, labels, curry)
 	if i >= len(metrics) {
 		return false
 	}
 
 	if len(metrics) > 1 {
-		m.children[h] = append(metrics[:i], metrics[i+1:]...)
+		m.metrics[h] = append(metrics[:i], metrics[i+1:]...)
 	} else {
-		delete(m.children, h)
+		delete(m.metrics, h)
 	}
 	return true
 }
 
-// Reset deletes all metrics in this vector.
-func (m *MetricVec) Reset() {
-	m.mtx.Lock()
-	defer m.mtx.Unlock()
-
-	for h := range m.children {
-		delete(m.children, h)
-	}
-}
-
-func (m *MetricVec) hashLabelValues(vals []string) (uint64, error) {
-	if len(vals) != len(m.desc.variableLabels) {
-		return 0, errInconsistentCardinality
-	}
-	h := hashNew()
-	for _, val := range vals {
-		h = m.hashAdd(h, val)
-		h = m.hashAddByte(h, model.SeparatorByte)
-	}
-	return h, nil
-}
-
-func (m *MetricVec) hashLabels(labels Labels) (uint64, error) {
-	if len(labels) != len(m.desc.variableLabels) {
-		return 0, errInconsistentCardinality
-	}
-	h := hashNew()
-	for _, label := range m.desc.variableLabels {
-		val, ok := labels[label]
-		if !ok {
-			return 0, fmt.Errorf("label name %q missing in label map", label)
-		}
-		h = m.hashAdd(h, val)
-		h = m.hashAddByte(h, model.SeparatorByte)
-	}
-	return h, nil
-}
-
 // getOrCreateMetricWithLabelValues retrieves the metric by hash and label value
 // or creates it and returns the new one.
 //
 // This function holds the mutex.
-func (m *MetricVec) getOrCreateMetricWithLabelValues(hash uint64, lvs []string) Metric {
+func (m *metricMap) getOrCreateMetricWithLabelValues(
+	hash uint64, lvs []string, curry []curriedLabelValue,
+) Metric {
 	m.mtx.RLock()
-	metric, ok := m.getMetricWithLabelValues(hash, lvs)
+	metric, ok := m.getMetricWithHashAndLabelValues(hash, lvs, curry)
 	m.mtx.RUnlock()
 	if ok {
 		return metric
@@ -291,13 +310,11 @@ func (m *MetricVec) getOrCreateMetricWithLabelValues(hash uint64, lvs []string)
 
 	m.mtx.Lock()
 	defer m.mtx.Unlock()
-	metric, ok = m.getMetricWithLabelValues(hash, lvs)
+	metric, ok = m.getMetricWithHashAndLabelValues(hash, lvs, curry)
 	if !ok {
-		// Copy to avoid allocation in case wo don't go down this code path.
+		inlinedLVs := inlineLabelValues(lvs, curry)
-		copiedLVs := make([]string, len(lvs))
+		metric = m.newMetric(inlinedLVs...)
-		copy(copiedLVs, lvs)
+		m.metrics[hash] = append(m.metrics[hash], metricWithLabelValues{values: inlinedLVs, metric: metric})
-		metric = m.newMetric(copiedLVs...)
-		m.children[hash] = append(m.children[hash], metricWithLabelValues{values: copiedLVs, metric: metric})
 	}
 	return metric
 }
@@ -306,9 +323,11 @@ func (m *MetricVec) getOrCreateMetricWithLabelValues(hash uint64, lvs []string)
 // or creates it and returns the new one.
 //
 // This function holds the mutex.
-func (m *MetricVec) getOrCreateMetricWithLabels(hash uint64, labels Labels) Metric {
+func (m *metricMap) getOrCreateMetricWithLabels(
+	hash uint64, labels Labels, curry []curriedLabelValue,
+) Metric {
 	m.mtx.RLock()
-	metric, ok := m.getMetricWithLabels(hash, labels)
+	metric, ok := m.getMetricWithHashAndLabels(hash, labels, curry)
 	m.mtx.RUnlock()
 	if ok {
 		return metric
@@ -316,33 +335,37 @@ func (m *MetricVec) getOrCreateMetricWithLabels(hash uint64, labels Labels) Metr
 
 	m.mtx.Lock()
 	defer m.mtx.Unlock()
-	metric, ok = m.getMetricWithLabels(hash, labels)
+	metric, ok = m.getMetricWithHashAndLabels(hash, labels, curry)
 	if !ok {
-		lvs := m.extractLabelValues(labels)
+		lvs := extractLabelValues(m.desc, labels, curry)
 		metric = m.newMetric(lvs...)
-		m.children[hash] = append(m.children[hash], metricWithLabelValues{values: lvs, metric: metric})
+		m.metrics[hash] = append(m.metrics[hash], metricWithLabelValues{values: lvs, metric: metric})
 	}
 	return metric
 }
 
-// getMetricWithLabelValues gets a metric while handling possible collisions in
+// getMetricWithHashAndLabelValues gets a metric while handling possible
-// the hash space. Must be called while holding read mutex.
+// collisions in the hash space. Must be called while holding the read mutex.
-func (m *MetricVec) getMetricWithLabelValues(h uint64, lvs []string) (Metric, bool) {
+func (m *metricMap) getMetricWithHashAndLabelValues(
-	metrics, ok := m.children[h]
+	h uint64, lvs []string, curry []curriedLabelValue,
+) (Metric, bool) {
+	metrics, ok := m.metrics[h]
 	if ok {
-		if i := m.findMetricWithLabelValues(metrics, lvs); i < len(metrics) {
+		if i := findMetricWithLabelValues(metrics, lvs, curry); i < len(metrics) {
 			return metrics[i].metric, true
 		}
 	}
 	return nil, false
 }
 
-// getMetricWithLabels gets a metric while handling possible collisions in
+// getMetricWithHashAndLabels gets a metric while handling possible collisions in
 // the hash space. Must be called while holding read mutex.
-func (m *MetricVec) getMetricWithLabels(h uint64, labels Labels) (Metric, bool) {
+func (m *metricMap) getMetricWithHashAndLabels(
-	metrics, ok := m.children[h]
+	h uint64, labels Labels, curry []curriedLabelValue,
+) (Metric, bool) {
+	metrics, ok := m.metrics[h]
 	if ok {
-		if i := m.findMetricWithLabels(metrics, labels); i < len(metrics) {
+		if i := findMetricWithLabels(m.desc, metrics, labels, curry); i < len(metrics) {
 			return metrics[i].metric, true
 		}
 	}
@@ -351,9 +374,11 @@ func (m *MetricVec) getMetricWithLabels(h uint64, labels Labels) (Metric, bool)
 
 // findMetricWithLabelValues returns the index of the matching metric or
 // len(metrics) if not found.
-func (m *MetricVec) findMetricWithLabelValues(metrics []metricWithLabelValues, lvs []string) int {
+func findMetricWithLabelValues(
+	metrics []metricWithLabelValues, lvs []string, curry []curriedLabelValue,
+) int {
 	for i, metric := range metrics {
-		if m.matchLabelValues(metric.values, lvs) {
+		if matchLabelValues(metric.values, lvs, curry) {
 			return i
 		}
 	}
@@ -362,32 +387,51 @@ func (m *MetricVec) findMetricWithLabelValues(metrics []metricWithLabelValues, l
 
 // findMetricWithLabels returns the index of the matching metric or len(metrics)
 // if not found.
-func (m *MetricVec) findMetricWithLabels(metrics []metricWithLabelValues, labels Labels) int {
+func findMetricWithLabels(
+	desc *Desc, metrics []metricWithLabelValues, labels Labels, curry []curriedLabelValue,
+) int {
 	for i, metric := range metrics {
-		if m.matchLabels(metric.values, labels) {
+		if matchLabels(desc, metric.values, labels, curry) {
 			return i
 		}
 	}
 	return len(metrics)
 }
 
-func (m *MetricVec) matchLabelValues(values []string, lvs []string) bool {
+func matchLabelValues(values []string, lvs []string, curry []curriedLabelValue) bool {
-	if len(values) != len(lvs) {
+	if len(values) != len(lvs)+len(curry) {
 		return false
 	}
+	var iLVs, iCurry int
 	for i, v := range values {
-		if v != lvs[i] {
+		if iCurry < len(curry) && curry[iCurry].index == i {
+			if v != curry[iCurry].value {
+				return false
+			}
+			iCurry++
+			continue
+		}
+		if v != lvs[iLVs] {
 			return false
 		}
+		iLVs++
 	}
 	return true
 }
 
-func (m *MetricVec) matchLabels(values []string, labels Labels) bool {
+func matchLabels(desc *Desc, values []string, labels Labels, curry []curriedLabelValue) bool {
-	if len(labels) != len(values) {
+	if len(values) != len(labels)+len(curry) {
 		return false
 	}
-	for i, k := range m.desc.variableLabels {
+	iCurry := 0
+	for i, k := range desc.variableLabels {
+		if iCurry < len(curry) && curry[iCurry].index == i {
+			if values[i] != curry[iCurry].value {
+				return false
+			}
+			iCurry++
+			continue
+		}
 		if values[i] != labels[k] {
 			return false
 		}
@@ -395,10 +439,31 @@ func (m *MetricVec) matchLabels(values []string, labels Labels) bool {
 	return true
 }
 
-func (m *MetricVec) extractLabelValues(labels Labels) []string {
+func extractLabelValues(desc *Desc, labels Labels, curry []curriedLabelValue) []string {
-	labelValues := make([]string, len(labels))
+	labelValues := make([]string, len(labels)+len(curry))
-	for i, k := range m.desc.variableLabels {
+	iCurry := 0
+	for i, k := range desc.variableLabels {
+		if iCurry < len(curry) && curry[iCurry].index == i {
+			labelValues[i] = curry[iCurry].value
+			iCurry++
+			continue
+		}
 		labelValues[i] = labels[k]
 	}
 	return labelValues
 }
+
+func inlineLabelValues(lvs []string, curry []curriedLabelValue) []string {
+	labelValues := make([]string, len(lvs)+len(curry))
+	var iCurry, iLVs int
+	for i := range labelValues {
+		if iCurry < len(curry) && curry[iCurry].index == i {
+			labelValues[i] = curry[iCurry].value
+			iCurry++
+			continue
+		}
+		labelValues[i] = lvs[iLVs]
+		iLVs++
+	}
+	return labelValues
+}

vendor/github.com/prometheus/common/README.md

@@ -6,7 +6,7 @@ components and libraries.
 
 * **config**: Common configuration structures
 * **expfmt**: Decoding and encoding for the exposition format
-* **log**: A logging wrapper around [logrus](https://github.com/Sirupsen/logrus)
+* **log**: A logging wrapper around [logrus](https://github.com/sirupsen/logrus)
 * **model**: Shared data structures
 * **route**: A routing wrapper around [httprouter](https://github.com/julienschmidt/httprouter) using `context.Context`
 * **version**: Version informations and metric

vendor/github.com/prometheus/common/expfmt/decode.go

@@ -31,6 +31,7 @@ type Decoder interface {
 	Decode(*dto.MetricFamily) error
 }
 
+// DecodeOptions contains options used by the Decoder and in sample extraction.
 type DecodeOptions struct {
 	// Timestamp is added to each value from the stream that has no explicit timestamp set.
 	Timestamp model.Time
@@ -142,6 +143,8 @@ func (d *textDecoder) Decode(v *dto.MetricFamily) error {
 	return nil
 }
 
+// SampleDecoder wraps a Decoder to extract samples from the metric families
+// decoded by the wrapped Decoder.
 type SampleDecoder struct {
 	Dec  Decoder
 	Opts *DecodeOptions
@@ -149,37 +152,51 @@ type SampleDecoder struct {
 	f dto.MetricFamily
 }
 
+// Decode calls the Decode method of the wrapped Decoder and then extracts the
+// samples from the decoded MetricFamily into the provided model.Vector.
 func (sd *SampleDecoder) Decode(s *model.Vector) error {
-	if err := sd.Dec.Decode(&sd.f); err != nil {
+	err := sd.Dec.Decode(&sd.f)
+	if err != nil {
 		return err
 	}
-	*s = extractSamples(&sd.f, sd.Opts)
+	*s, err = extractSamples(&sd.f, sd.Opts)
-	return nil
+	return err
 }
 
-// Extract samples builds a slice of samples from the provided metric families.
+// ExtractSamples builds a slice of samples from the provided metric
-func ExtractSamples(o *DecodeOptions, fams ...*dto.MetricFamily) model.Vector {
+// families. If an error occurs during sample extraction, it continues to
-	var all model.Vector
+// extract from the remaining metric families. The returned error is the last
+// error that has occured.
+func ExtractSamples(o *DecodeOptions, fams ...*dto.MetricFamily) (model.Vector, error) {
+	var (
+		all     model.Vector
+		lastErr error
+	)
 	for _, f := range fams {
-		all = append(all, extractSamples(f, o)...)
+		some, err := extractSamples(f, o)
+		if err != nil {
+			lastErr = err
+			continue
+		}
+		all = append(all, some...)
 	}
-	return all
+	return all, lastErr
 }
 
-func extractSamples(f *dto.MetricFamily, o *DecodeOptions) model.Vector {
+func extractSamples(f *dto.MetricFamily, o *DecodeOptions) (model.Vector, error) {
 	switch f.GetType() {
 	case dto.MetricType_COUNTER:
-		return extractCounter(o, f)
+		return extractCounter(o, f), nil
 	case dto.MetricType_GAUGE:
-		return extractGauge(o, f)
+		return extractGauge(o, f), nil
 	case dto.MetricType_SUMMARY:
-		return extractSummary(o, f)
+		return extractSummary(o, f), nil
 	case dto.MetricType_UNTYPED:
-		return extractUntyped(o, f)
+		return extractUntyped(o, f), nil
 	case dto.MetricType_HISTOGRAM:
-		return extractHistogram(o, f)
+		return extractHistogram(o, f), nil
 	}
-	panic("expfmt.extractSamples: unknown metric family type")
+	return nil, fmt.Errorf("expfmt.extractSamples: unknown metric family type %v", f.GetType())
 }
 
 func extractCounter(o *DecodeOptions, f *dto.MetricFamily) model.Vector {

vendor/github.com/prometheus/common/expfmt/expfmt.go

@@ -11,14 +11,15 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-// A package for reading and writing Prometheus metrics.
+// Package expfmt contains tools for reading and writing Prometheus metrics.
 package expfmt
 
+// Format specifies the HTTP content type of the different wire protocols.
 type Format string
 
+// Constants to assemble the Content-Type values for the different wire protocols.
 const (
-	TextVersion = "0.0.4"
+	TextVersion   = "0.0.4"
-
 	ProtoType     = `application/vnd.google.protobuf`
 	ProtoProtocol = `io.prometheus.client.MetricFamily`
 	ProtoFmt      = ProtoType + "; proto=" + ProtoProtocol + ";"

vendor/github.com/prometheus/common/expfmt/text_parse.go

@@ -315,6 +315,10 @@ func (p *TextParser) startLabelValue() stateFn {
 	if p.readTokenAsLabelValue(); p.err != nil {
 		return nil
 	}
+	if !model.LabelValue(p.currentToken.String()).IsValid() {
+		p.parseError(fmt.Sprintf("invalid label value %q", p.currentToken.String()))
+		return nil
+	}
 	p.currentLabelPair.Value = proto.String(p.currentToken.String())
 	// Special treatment of summaries:
 	// - Quantile labels are special, will result in dto.Quantile later.

vendor/github.com/prometheus/common/model/metric.go

@@ -44,7 +44,7 @@ func (m Metric) Before(o Metric) bool {
 
 // Clone returns a copy of the Metric.
 func (m Metric) Clone() Metric {
-	clone := Metric{}
+	clone := make(Metric, len(m))
 	for k, v := range m {
 		clone[k] = v
 	}

vendor/github.com/prometheus/common/model/time.go

@@ -163,9 +163,21 @@ func (t *Time) UnmarshalJSON(b []byte) error {
 // This type should not propagate beyond the scope of input/output processing.
 type Duration time.Duration
 
+// Set implements pflag/flag.Value
+func (d *Duration) Set(s string) error {
+	var err error
+	*d, err = ParseDuration(s)
+	return err
+}
+
+// Type implements pflag.Value
+func (d *Duration) Type() string {
+	return "duration"
+}
+
 var durationRE = regexp.MustCompile("^([0-9]+)(y|w|d|h|m|s|ms)$")
 
-// StringToDuration parses a string into a time.Duration, assuming that a year
+// ParseDuration parses a string into a time.Duration, assuming that a year
 // always has 365d, a week always has 7d, and a day always has 24h.
 func ParseDuration(durationStr string) (Duration, error) {
 	matches := durationRE.FindStringSubmatch(durationStr)
@@ -202,6 +214,9 @@ func (d Duration) String() string {
 		ms   = int64(time.Duration(d) / time.Millisecond)
 		unit = "ms"
 	)
+	if ms == 0 {
+		return "0s"
+	}
 	factors := map[string]int64{
 		"y":  1000 * 60 * 60 * 24 * 365,
 		"w":  1000 * 60 * 60 * 24 * 7,

vendor/github.com/prometheus/common/model/value.go

@@ -129,11 +129,8 @@ func (s *Sample) Equal(o *Sample) bool {
 	if !s.Timestamp.Equal(o.Timestamp) {
 		return false
 	}
-	if s.Value.Equal(o.Value) {
-		return false
-	}
 
-	return true
+	return s.Value.Equal(o.Value)
 }
 
 func (s Sample) String() string {

vendor/github.com/prometheus/procfs/README.md

@@ -8,3 +8,4 @@ backwards-incompatible ways without warnings. Use it at your own risk.
 
 [![GoDoc](https://godoc.org/github.com/prometheus/procfs?status.png)](https://godoc.org/github.com/prometheus/procfs)
 [![Build Status](https://travis-ci.org/prometheus/procfs.svg?branch=master)](https://travis-ci.org/prometheus/procfs)
+[![Go Report Card](https://goreportcard.com/badge/github.com/prometheus/procfs)](https://goreportcard.com/report/github.com/prometheus/procfs)

vendor/github.com/prometheus/procfs/buddyinfo.go

@@ -0,0 +1,95 @@
+// 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 procfs
+
+import (
+	"bufio"
+	"fmt"
+	"io"
+	"os"
+	"strconv"
+	"strings"
+)
+
+// A BuddyInfo is the details parsed from /proc/buddyinfo.
+// The data is comprised of an array of free fragments of each size.
+// The sizes are 2^n*PAGE_SIZE, where n is the array index.
+type BuddyInfo struct {
+	Node  string
+	Zone  string
+	Sizes []float64
+}
+
+// NewBuddyInfo reads the buddyinfo statistics.
+func NewBuddyInfo() ([]BuddyInfo, error) {
+	fs, err := NewFS(DefaultMountPoint)
+	if err != nil {
+		return nil, err
+	}
+
+	return fs.NewBuddyInfo()
+}
+
+// NewBuddyInfo reads the buddyinfo statistics from the specified `proc` filesystem.
+func (fs FS) NewBuddyInfo() ([]BuddyInfo, error) {
+	file, err := os.Open(fs.Path("buddyinfo"))
+	if err != nil {
+		return nil, err
+	}
+	defer file.Close()
+
+	return parseBuddyInfo(file)
+}
+
+func parseBuddyInfo(r io.Reader) ([]BuddyInfo, error) {
+	var (
+		buddyInfo   = []BuddyInfo{}
+		scanner     = bufio.NewScanner(r)
+		bucketCount = -1
+	)
+
+	for scanner.Scan() {
+		var err error
+		line := scanner.Text()
+		parts := strings.Fields(line)
+
+		if len(parts) < 4 {
+			return nil, fmt.Errorf("invalid number of fields when parsing buddyinfo")
+		}
+
+		node := strings.TrimRight(parts[1], ",")
+		zone := strings.TrimRight(parts[3], ",")
+		arraySize := len(parts[4:])
+
+		if bucketCount == -1 {
+			bucketCount = arraySize
+		} else {
+			if bucketCount != arraySize {
+				return nil, fmt.Errorf("mismatch in number of buddyinfo buckets, previous count %d, new count %d", bucketCount, arraySize)
+			}
+		}
+
+		sizes := make([]float64, arraySize)
+		for i := 0; i < arraySize; i++ {
+			sizes[i], err = strconv.ParseFloat(parts[i+4], 64)
+			if err != nil {
+				return nil, fmt.Errorf("invalid value in buddyinfo: %s", err)
+			}
+		}
+
+		buddyInfo = append(buddyInfo, BuddyInfo{node, zone, sizes})
+	}
+
+	return buddyInfo, scanner.Err()
+}

vendor/github.com/prometheus/procfs/fs.go

@@ -4,6 +4,9 @@ import (
 	"fmt"
 	"os"
 	"path"
+
+	"github.com/prometheus/procfs/nfs"
+	"github.com/prometheus/procfs/xfs"
 )
 
 // FS represents the pseudo-filesystem proc, which provides an interface to
@@ -31,3 +34,36 @@ func NewFS(mountPoint string) (FS, error) {
 func (fs FS) Path(p ...string) string {
 	return path.Join(append([]string{string(fs)}, p...)...)
 }
+
+// XFSStats retrieves XFS filesystem runtime statistics.
+func (fs FS) XFSStats() (*xfs.Stats, error) {
+	f, err := os.Open(fs.Path("fs/xfs/stat"))
+	if err != nil {
+		return nil, err
+	}
+	defer f.Close()
+
+	return xfs.ParseStats(f)
+}
+
+// NFSdClientRPCStats retrieves NFS daemon RPC statistics.
+func (fs FS) NFSdClientRPCStats() (*nfs.ClientRPCStats, error) {
+	f, err := os.Open(fs.Path("net/rpc/nfs"))
+	if err != nil {
+		return nil, err
+	}
+	defer f.Close()
+
+	return nfs.ParseClientRPCStats(f)
+}
+
+// NFSdServerRPCStats retrieves NFS daemon RPC statistics.
+func (fs FS) NFSdServerRPCStats() (*nfs.ServerRPCStats, error) {
+	f, err := os.Open(fs.Path("net/rpc/nfsd"))
+	if err != nil {
+		return nil, err
+	}
+	defer f.Close()
+
+	return nfs.ParseServerRPCStats(f)
+}

vendor/github.com/prometheus/procfs/internal/util/parse.go

@@ -0,0 +1,46 @@
+// Copyright 2018 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 util
+
+import "strconv"
+
+// ParseUint32s parses a slice of strings into a slice of uint32s.
+func ParseUint32s(ss []string) ([]uint32, error) {
+	us := make([]uint32, 0, len(ss))
+	for _, s := range ss {
+		u, err := strconv.ParseUint(s, 10, 32)
+		if err != nil {
+			return nil, err
+		}
+
+		us = append(us, uint32(u))
+	}
+
+	return us, nil
+}
+
+// ParseUint64s parses a slice of strings into a slice of uint64s.
+func ParseUint64s(ss []string) ([]uint64, error) {
+	us := make([]uint64, 0, len(ss))
+	for _, s := range ss {
+		u, err := strconv.ParseUint(s, 10, 64)
+		if err != nil {
+			return nil, err
+		}
+
+		us = append(us, u)
+	}
+
+	return us, nil
+}

vendor/github.com/prometheus/procfs/ipvs.go

@@ -31,14 +31,16 @@ type IPVSStats struct {
 type IPVSBackendStatus struct {
 	// The local (virtual) IP address.
 	LocalAddress net.IP
-	// The local (virtual) port.
-	LocalPort uint16
-	// The transport protocol (TCP, UDP).
-	Proto string
 	// The remote (real) IP address.
 	RemoteAddress net.IP
+	// The local (virtual) port.
+	LocalPort uint16
 	// The remote (real) port.
 	RemotePort uint16
+	// The local firewall mark
+	LocalMark string
+	// The transport protocol (TCP, UDP).
+	Proto string
 	// The current number of active connections for this virtual/real address pair.
 	ActiveConn uint64
 	// The current number of inactive connections for this virtual/real address pair.
@@ -142,13 +144,14 @@ func parseIPVSBackendStatus(file io.Reader) ([]IPVSBackendStatus, error) {
 		status       []IPVSBackendStatus
 		scanner      = bufio.NewScanner(file)
 		proto        string
+		localMark    string
 		localAddress net.IP
 		localPort    uint16
 		err          error
 	)
 
 	for scanner.Scan() {
-		fields := strings.Fields(string(scanner.Text()))
+		fields := strings.Fields(scanner.Text())
 		if len(fields) == 0 {
 			continue
 		}
@@ -160,10 +163,19 @@ func parseIPVSBackendStatus(file io.Reader) ([]IPVSBackendStatus, error) {
 				continue
 			}
 			proto = fields[0]
+			localMark = ""
 			localAddress, localPort, err = parseIPPort(fields[1])
 			if err != nil {
 				return nil, err
 			}
+		case fields[0] == "FWM":
+			if len(fields) < 2 {
+				continue
+			}
+			proto = fields[0]
+			localMark = fields[1]
+			localAddress = nil
+			localPort = 0
 		case fields[0] == "->":
 			if len(fields) < 6 {
 				continue
@@ -187,6 +199,7 @@ func parseIPVSBackendStatus(file io.Reader) ([]IPVSBackendStatus, error) {
 			status = append(status, IPVSBackendStatus{
 				LocalAddress:  localAddress,
 				LocalPort:     localPort,
+				LocalMark:     localMark,
 				RemoteAddress: remoteAddress,
 				RemotePort:    remotePort,
 				Proto:         proto,
@@ -200,22 +213,31 @@ func parseIPVSBackendStatus(file io.Reader) ([]IPVSBackendStatus, error) {
 }
 
 func parseIPPort(s string) (net.IP, uint16, error) {
-	tmp := strings.SplitN(s, ":", 2)
+	var (
+		ip  net.IP
+		err error
+	)
 
-	if len(tmp) != 2 {
+	switch len(s) {
-		return nil, 0, fmt.Errorf("invalid IP:Port: %s", s)
+	case 13:
+		ip, err = hex.DecodeString(s[0:8])
+		if err != nil {
+			return nil, 0, err
+		}
+	case 46:
+		ip = net.ParseIP(s[1:40])
+		if ip == nil {
+			return nil, 0, fmt.Errorf("invalid IPv6 address: %s", s[1:40])
+		}
+	default:
+		return nil, 0, fmt.Errorf("unexpected IP:Port: %s", s)
 	}
 
-	if len(tmp[0]) != 8 && len(tmp[0]) != 32 {
+	portString := s[len(s)-4:]
-		return nil, 0, fmt.Errorf("invalid IP: %s", tmp[0])
+	if len(portString) != 4 {
+		return nil, 0, fmt.Errorf("unexpected port string format: %s", portString)
 	}
-
+	port, err := strconv.ParseUint(portString, 16, 16)
-	ip, err := hex.DecodeString(tmp[0])
-	if err != nil {
-		return nil, 0, err
-	}
-
-	port, err := strconv.ParseUint(tmp[1], 16, 16)
 	if err != nil {
 		return nil, 0, err
 	}

vendor/github.com/prometheus/procfs/mountstats.go

@@ -72,80 +72,80 @@ func (m MountStatsNFS) mountStats() {}
 // by an NFS client to and from an NFS server.
 type NFSBytesStats struct {
 	// Number of bytes read using the read() syscall.
-	Read int
+	Read uint64
 	// Number of bytes written using the write() syscall.
-	Write int
+	Write uint64
 	// Number of bytes read using the read() syscall in O_DIRECT mode.
-	DirectRead int
+	DirectRead uint64
 	// Number of bytes written using the write() syscall in O_DIRECT mode.
-	DirectWrite int
+	DirectWrite uint64
 	// Number of bytes read from the NFS server, in total.
-	ReadTotal int
+	ReadTotal uint64
 	// Number of bytes written to the NFS server, in total.
-	WriteTotal int
+	WriteTotal uint64
 	// Number of pages read directly via mmap()'d files.
-	ReadPages int
+	ReadPages uint64
 	// Number of pages written directly via mmap()'d files.
-	WritePages int
+	WritePages uint64
 }
 
 // A NFSEventsStats contains statistics about NFS event occurrences.
 type NFSEventsStats struct {
 	// Number of times cached inode attributes are re-validated from the server.
-	InodeRevalidate int
+	InodeRevalidate uint64
 	// Number of times cached dentry nodes are re-validated from the server.
-	DnodeRevalidate int
+	DnodeRevalidate uint64
 	// Number of times an inode cache is cleared.
-	DataInvalidate int
+	DataInvalidate uint64
 	// Number of times cached inode attributes are invalidated.
-	AttributeInvalidate int
+	AttributeInvalidate uint64
 	// Number of times files or directories have been open()'d.
-	VFSOpen int
+	VFSOpen uint64
 	// Number of times a directory lookup has occurred.
-	VFSLookup int
+	VFSLookup uint64
 	// Number of times permissions have been checked.
-	VFSAccess int
+	VFSAccess uint64
 	// Number of updates (and potential writes) to pages.
-	VFSUpdatePage int
+	VFSUpdatePage uint64
 	// Number of pages read directly via mmap()'d files.
-	VFSReadPage int
+	VFSReadPage uint64
 	// Number of times a group of pages have been read.
-	VFSReadPages int
+	VFSReadPages uint64
 	// Number of pages written directly via mmap()'d files.
-	VFSWritePage int
+	VFSWritePage uint64
 	// Number of times a group of pages have been written.
-	VFSWritePages int
+	VFSWritePages uint64
 	// Number of times directory entries have been read with getdents().
-	VFSGetdents int
+	VFSGetdents uint64
 	// Number of times attributes have been set on inodes.
-	VFSSetattr int
+	VFSSetattr uint64
 	// Number of pending writes that have been forcefully flushed to the server.
-	VFSFlush int
+	VFSFlush uint64
 	// Number of times fsync() has been called on directories and files.
-	VFSFsync int
+	VFSFsync uint64
-	// Number of times locking has been attemped on a file.
+	// Number of times locking has been attempted on a file.
-	VFSLock int
+	VFSLock uint64
 	// Number of times files have been closed and released.
-	VFSFileRelease int
+	VFSFileRelease uint64
 	// Unknown.  Possibly unused.
-	CongestionWait int
+	CongestionWait uint64
 	// Number of times files have been truncated.
-	Truncation int
+	Truncation uint64
 	// Number of times a file has been grown due to writes beyond its existing end.
-	WriteExtension int
+	WriteExtension uint64
 	// Number of times a file was removed while still open by another process.
-	SillyRename int
+	SillyRename uint64
 	// Number of times the NFS server gave less data than expected while reading.
-	ShortRead int
+	ShortRead uint64
 	// Number of times the NFS server wrote less data than expected while writing.
-	ShortWrite int
+	ShortWrite uint64
 	// Number of times the NFS server indicated EJUKEBOX; retrieving data from
 	// offline storage.
-	JukeboxDelay int
+	JukeboxDelay uint64
 	// Number of NFS v4.1+ pNFS reads.
-	PNFSRead int
+	PNFSRead uint64
 	// Number of NFS v4.1+ pNFS writes.
-	PNFSWrite int
+	PNFSWrite uint64
 }
 
 // A NFSOperationStats contains statistics for a single operation.
@@ -153,15 +153,15 @@ type NFSOperationStats struct {
 	// The name of the operation.
 	Operation string
 	// Number of requests performed for this operation.
-	Requests int
+	Requests uint64
 	// Number of times an actual RPC request has been transmitted for this operation.
-	Transmissions int
+	Transmissions uint64
 	// Number of times a request has had a major timeout.
-	MajorTimeouts int
+	MajorTimeouts uint64
 	// Number of bytes sent for this operation, including RPC headers and payload.
-	BytesSent int
+	BytesSent uint64
 	// Number of bytes received for this operation, including RPC headers and payload.
-	BytesReceived int
+	BytesReceived uint64
 	// Duration all requests spent queued for transmission before they were sent.
 	CumulativeQueueTime time.Duration
 	// Duration it took to get a reply back after the request was transmitted.
@@ -174,41 +174,41 @@ type NFSOperationStats struct {
 // responses.
 type NFSTransportStats struct {
 	// The local port used for the NFS mount.
-	Port int
+	Port uint64
 	// Number of times the client has had to establish a connection from scratch
 	// to the NFS server.
-	Bind int
+	Bind uint64
 	// Number of times the client has made a TCP connection to the NFS server.
-	Connect int
+	Connect uint64
 	// Duration (in jiffies, a kernel internal unit of time) the NFS mount has
 	// spent waiting for connections to the server to be established.
-	ConnectIdleTime int
+	ConnectIdleTime uint64
 	// Duration since the NFS mount last saw any RPC traffic.
 	IdleTime time.Duration
 	// Number of RPC requests for this mount sent to the NFS server.
-	Sends int
+	Sends uint64
 	// Number of RPC responses for this mount received from the NFS server.
-	Receives int
+	Receives uint64
 	// Number of times the NFS server sent a response with a transaction ID
 	// unknown to this client.
-	BadTransactionIDs int
+	BadTransactionIDs uint64
 	// A running counter, incremented on each request as the current difference
 	// ebetween sends and receives.
-	CumulativeActiveRequests int
+	CumulativeActiveRequests uint64
 	// A running counter, incremented on each request by the current backlog
 	// queue size.
-	CumulativeBacklog int
+	CumulativeBacklog uint64
 
 	// Stats below only available with stat version 1.1.
 
 	// Maximum number of simultaneously active RPC requests ever used.
-	MaximumRPCSlotsUsed int
+	MaximumRPCSlotsUsed uint64
 	// A running counter, incremented on each request as the current size of the
 	// sending queue.
-	CumulativeSendingQueue int
+	CumulativeSendingQueue uint64
 	// A running counter, incremented on each request as the current size of the
 	// pending queue.
-	CumulativePendingQueue int
+	CumulativePendingQueue uint64
 }
 
 // parseMountStats parses a /proc/[pid]/mountstats file and returns a slice
@@ -356,7 +356,7 @@ func parseMountStatsNFS(s *bufio.Scanner, statVersion string) (*MountStatsNFS, e
 		}
 
 		// When encountering "per-operation statistics", we must break this
-		// loop and parse them seperately to ensure we can terminate parsing
+		// loop and parse them separately to ensure we can terminate parsing
 		// before reaching another device entry; hence why this 'if' statement
 		// is not just another switch case
 		if ss[0] == fieldPerOpStats {
@@ -386,9 +386,9 @@ func parseNFSBytesStats(ss []string) (*NFSBytesStats, error) {
 		return nil, fmt.Errorf("invalid NFS bytes stats: %v", ss)
 	}
 
-	ns := make([]int, 0, fieldBytesLen)
+	ns := make([]uint64, 0, fieldBytesLen)
 	for _, s := range ss {
-		n, err := strconv.Atoi(s)
+		n, err := strconv.ParseUint(s, 10, 64)
 		if err != nil {
 			return nil, err
 		}
@@ -415,9 +415,9 @@ func parseNFSEventsStats(ss []string) (*NFSEventsStats, error) {
 		return nil, fmt.Errorf("invalid NFS events stats: %v", ss)
 	}
 
-	ns := make([]int, 0, fieldEventsLen)
+	ns := make([]uint64, 0, fieldEventsLen)
 	for _, s := range ss {
-		n, err := strconv.Atoi(s)
+		n, err := strconv.ParseUint(s, 10, 64)
 		if err != nil {
 			return nil, err
 		}
@@ -480,9 +480,9 @@ func parseNFSOperationStats(s *bufio.Scanner) ([]NFSOperationStats, error) {
 		}
 
 		// Skip string operation name for integers
-		ns := make([]int, 0, numFields-1)
+		ns := make([]uint64, 0, numFields-1)
 		for _, st := range ss[1:] {
-			n, err := strconv.Atoi(st)
+			n, err := strconv.ParseUint(st, 10, 64)
 			if err != nil {
 				return nil, err
 			}
@@ -523,15 +523,19 @@ func parseNFSTransportStats(ss []string, statVersion string) (*NFSTransportStats
 	}
 
 	// Allocate enough for v1.1 stats since zero value for v1.1 stats will be okay
-	// in a v1.0 response
+	// in a v1.0 response.
-	ns := make([]int, 0, fieldTransport11Len)
+	//
-	for _, s := range ss {
+	// Note: slice length must be set to length of v1.1 stats to avoid a panic when
-		n, err := strconv.Atoi(s)
+	// only v1.0 stats are present.
+	// See: https://github.com/prometheus/node_exporter/issues/571.
+	ns := make([]uint64, fieldTransport11Len)
+	for i, s := range ss {
+		n, err := strconv.ParseUint(s, 10, 64)
 		if err != nil {
 			return nil, err
 		}
 
-		ns = append(ns, n)
+		ns[i] = n
 	}
 
 	return &NFSTransportStats{

vendor/github.com/prometheus/procfs/net_dev.go

@@ -0,0 +1,203 @@
+package procfs
+
+import (
+	"bufio"
+	"errors"
+	"os"
+	"sort"
+	"strconv"
+	"strings"
+)
+
+// NetDevLine is single line parsed from /proc/net/dev or /proc/[pid]/net/dev.
+type NetDevLine struct {
+	Name         string `json:"name"`          // The name of the interface.
+	RxBytes      uint64 `json:"rx_bytes"`      // Cumulative count of bytes received.
+	RxPackets    uint64 `json:"rx_packets"`    // Cumulative count of packets received.
+	RxErrors     uint64 `json:"rx_errors"`     // Cumulative count of receive errors encountered.
+	RxDropped    uint64 `json:"rx_dropped"`    // Cumulative count of packets dropped while receiving.
+	RxFIFO       uint64 `json:"rx_fifo"`       // Cumulative count of FIFO buffer errors.
+	RxFrame      uint64 `json:"rx_frame"`      // Cumulative count of packet framing errors.
+	RxCompressed uint64 `json:"rx_compressed"` // Cumulative count of compressed packets received by the device driver.
+	RxMulticast  uint64 `json:"rx_multicast"`  // Cumulative count of multicast frames received by the device driver.
+	TxBytes      uint64 `json:"tx_bytes"`      // Cumulative count of bytes transmitted.
+	TxPackets    uint64 `json:"tx_packets"`    // Cumulative count of packets transmitted.
+	TxErrors     uint64 `json:"tx_errors"`     // Cumulative count of transmit errors encountered.
+	TxDropped    uint64 `json:"tx_dropped"`    // Cumulative count of packets dropped while transmitting.
+	TxFIFO       uint64 `json:"tx_fifo"`       // Cumulative count of FIFO buffer errors.
+	TxCollisions uint64 `json:"tx_collisions"` // Cumulative count of collisions detected on the interface.
+	TxCarrier    uint64 `json:"tx_carrier"`    // Cumulative count of carrier losses detected by the device driver.
+	TxCompressed uint64 `json:"tx_compressed"` // Cumulative count of compressed packets transmitted by the device driver.
+}
+
+// NetDev is parsed from /proc/net/dev or /proc/[pid]/net/dev. The map keys
+// are interface names.
+type NetDev map[string]NetDevLine
+
+// NewNetDev returns kernel/system statistics read from /proc/net/dev.
+func NewNetDev() (NetDev, error) {
+	fs, err := NewFS(DefaultMountPoint)
+	if err != nil {
+		return nil, err
+	}
+
+	return fs.NewNetDev()
+}
+
+// NewNetDev returns kernel/system statistics read from /proc/net/dev.
+func (fs FS) NewNetDev() (NetDev, error) {
+	return newNetDev(fs.Path("net/dev"))
+}
+
+// NewNetDev returns kernel/system statistics read from /proc/[pid]/net/dev.
+func (p Proc) NewNetDev() (NetDev, error) {
+	return newNetDev(p.path("net/dev"))
+}
+
+// newNetDev creates a new NetDev from the contents of the given file.
+func newNetDev(file string) (NetDev, error) {
+	f, err := os.Open(file)
+	if err != nil {
+		return NetDev{}, err
+	}
+	defer f.Close()
+
+	nd := NetDev{}
+	s := bufio.NewScanner(f)
+	for n := 0; s.Scan(); n++ {
+		// Skip the 2 header lines.
+		if n < 2 {
+			continue
+		}
+
+		line, err := nd.parseLine(s.Text())
+		if err != nil {
+			return nd, err
+		}
+
+		nd[line.Name] = *line
+	}
+
+	return nd, s.Err()
+}
+
+// parseLine parses a single line from the /proc/net/dev file. Header lines
+// must be filtered prior to calling this method.
+func (nd NetDev) parseLine(rawLine string) (*NetDevLine, error) {
+	parts := strings.SplitN(rawLine, ":", 2)
+	if len(parts) != 2 {
+		return nil, errors.New("invalid net/dev line, missing colon")
+	}
+	fields := strings.Fields(strings.TrimSpace(parts[1]))
+
+	var err error
+	line := &NetDevLine{}
+
+	// Interface Name
+	line.Name = strings.TrimSpace(parts[0])
+	if line.Name == "" {
+		return nil, errors.New("invalid net/dev line, empty interface name")
+	}
+
+	// RX
+	line.RxBytes, err = strconv.ParseUint(fields[0], 10, 64)
+	if err != nil {
+		return nil, err
+	}
+	line.RxPackets, err = strconv.ParseUint(fields[1], 10, 64)
+	if err != nil {
+		return nil, err
+	}
+	line.RxErrors, err = strconv.ParseUint(fields[2], 10, 64)
+	if err != nil {
+		return nil, err
+	}
+	line.RxDropped, err = strconv.ParseUint(fields[3], 10, 64)
+	if err != nil {
+		return nil, err
+	}
+	line.RxFIFO, err = strconv.ParseUint(fields[4], 10, 64)
+	if err != nil {
+		return nil, err
+	}
+	line.RxFrame, err = strconv.ParseUint(fields[5], 10, 64)
+	if err != nil {
+		return nil, err
+	}
+	line.RxCompressed, err = strconv.ParseUint(fields[6], 10, 64)
+	if err != nil {
+		return nil, err
+	}
+	line.RxMulticast, err = strconv.ParseUint(fields[7], 10, 64)
+	if err != nil {
+		return nil, err
+	}
+
+	// TX
+	line.TxBytes, err = strconv.ParseUint(fields[8], 10, 64)
+	if err != nil {
+		return nil, err
+	}
+	line.TxPackets, err = strconv.ParseUint(fields[9], 10, 64)
+	if err != nil {
+		return nil, err
+	}
+	line.TxErrors, err = strconv.ParseUint(fields[10], 10, 64)
+	if err != nil {
+		return nil, err
+	}
+	line.TxDropped, err = strconv.ParseUint(fields[11], 10, 64)
+	if err != nil {
+		return nil, err
+	}
+	line.TxFIFO, err = strconv.ParseUint(fields[12], 10, 64)
+	if err != nil {
+		return nil, err
+	}
+	line.TxCollisions, err = strconv.ParseUint(fields[13], 10, 64)
+	if err != nil {
+		return nil, err
+	}
+	line.TxCarrier, err = strconv.ParseUint(fields[14], 10, 64)
+	if err != nil {
+		return nil, err
+	}
+	line.TxCompressed, err = strconv.ParseUint(fields[15], 10, 64)
+	if err != nil {
+		return nil, err
+	}
+
+	return line, nil
+}
+
+// Total aggregates the values across interfaces and returns a new NetDevLine.
+// The Name field will be a sorted comma seperated list of interface names.
+func (nd NetDev) Total() NetDevLine {
+	total := NetDevLine{}
+
+	names := make([]string, 0, len(nd))
+	for _, ifc := range nd {
+		names = append(names, ifc.Name)
+		total.RxBytes += ifc.RxBytes
+		total.RxPackets += ifc.RxPackets
+		total.RxPackets += ifc.RxPackets
+		total.RxErrors += ifc.RxErrors
+		total.RxDropped += ifc.RxDropped
+		total.RxFIFO += ifc.RxFIFO
+		total.RxFrame += ifc.RxFrame
+		total.RxCompressed += ifc.RxCompressed
+		total.RxMulticast += ifc.RxMulticast
+		total.TxBytes += ifc.TxBytes
+		total.TxPackets += ifc.TxPackets
+		total.TxErrors += ifc.TxErrors
+		total.TxDropped += ifc.TxDropped
+		total.TxFIFO += ifc.TxFIFO
+		total.TxCollisions += ifc.TxCollisions
+		total.TxCarrier += ifc.TxCarrier
+		total.TxCompressed += ifc.TxCompressed
+	}
+	sort.Strings(names)
+	total.Name = strings.Join(names, ", ")
+
+	return total
+}

vendor/github.com/prometheus/procfs/nfs/nfs.go

@@ -0,0 +1,263 @@
+// Copyright 2018 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 nfsd implements parsing of /proc/net/rpc/nfsd.
+// Fields are documented in https://www.svennd.be/nfsd-stats-explained-procnetrpcnfsd/
+package nfs
+
+// ReplyCache models the "rc" line.
+type ReplyCache struct {
+	Hits    uint64
+	Misses  uint64
+	NoCache uint64
+}
+
+// FileHandles models the "fh" line.
+type FileHandles struct {
+	Stale        uint64
+	TotalLookups uint64
+	AnonLookups  uint64
+	DirNoCache   uint64
+	NoDirNoCache uint64
+}
+
+// InputOutput models the "io" line.
+type InputOutput struct {
+	Read  uint64
+	Write uint64
+}
+
+// Threads models the "th" line.
+type Threads struct {
+	Threads uint64
+	FullCnt uint64
+}
+
+// ReadAheadCache models the "ra" line.
+type ReadAheadCache struct {
+	CacheSize      uint64
+	CacheHistogram []uint64
+	NotFound       uint64
+}
+
+// Network models the "net" line.
+type Network struct {
+	NetCount   uint64
+	UDPCount   uint64
+	TCPCount   uint64
+	TCPConnect uint64
+}
+
+// ClientRPC models the nfs "rpc" line.
+type ClientRPC struct {
+	RPCCount        uint64
+	Retransmissions uint64
+	AuthRefreshes   uint64
+}
+
+// ServerRPC models the nfsd "rpc" line.
+type ServerRPC struct {
+	RPCCount uint64
+	BadCnt   uint64
+	BadFmt   uint64
+	BadAuth  uint64
+	BadcInt  uint64
+}
+
+// V2Stats models the "proc2" line.
+type V2Stats struct {
+	Null     uint64
+	GetAttr  uint64
+	SetAttr  uint64
+	Root     uint64
+	Lookup   uint64
+	ReadLink uint64
+	Read     uint64
+	WrCache  uint64
+	Write    uint64
+	Create   uint64
+	Remove   uint64
+	Rename   uint64
+	Link     uint64
+	SymLink  uint64
+	MkDir    uint64
+	RmDir    uint64
+	ReadDir  uint64
+	FsStat   uint64
+}
+
+// V3Stats models the "proc3" line.
+type V3Stats struct {
+	Null        uint64
+	GetAttr     uint64
+	SetAttr     uint64
+	Lookup      uint64
+	Access      uint64
+	ReadLink    uint64
+	Read        uint64
+	Write       uint64
+	Create      uint64
+	MkDir       uint64
+	SymLink     uint64
+	MkNod       uint64
+	Remove      uint64
+	RmDir       uint64
+	Rename      uint64
+	Link        uint64
+	ReadDir     uint64
+	ReadDirPlus uint64
+	FsStat      uint64
+	FsInfo      uint64
+	PathConf    uint64
+	Commit      uint64
+}
+
+// ClientV4Stats models the nfs "proc4" line.
+type ClientV4Stats struct {
+	Null               uint64
+	Read               uint64
+	Write              uint64
+	Commit             uint64
+	Open               uint64
+	OpenConfirm        uint64
+	OpenNoattr         uint64
+	OpenDowngrade      uint64
+	Close              uint64
+	Setattr            uint64
+	FsInfo             uint64
+	Renew              uint64
+	SetClientId        uint64
+	SetClientIdConfirm uint64
+	Lock               uint64
+	Lockt              uint64
+	Locku              uint64
+	Access             uint64
+	Getattr            uint64
+	Lookup             uint64
+	LookupRoot         uint64
+	Remove             uint64
+	Rename             uint64
+	Link               uint64
+	Symlink            uint64
+	Create             uint64
+	Pathconf           uint64
+	StatFs             uint64
+	ReadLink           uint64
+	ReadDir            uint64
+	ServerCaps         uint64
+	DelegReturn        uint64
+	GetAcl             uint64
+	SetAcl             uint64
+	FsLocations        uint64
+	ReleaseLockowner   uint64
+	Secinfo            uint64
+	FsidPresent        uint64
+	ExchangeId         uint64
+	CreateSession      uint64
+	DestroySession     uint64
+	Sequence           uint64
+	GetLeaseTime       uint64
+	ReclaimComplete    uint64
+	LayoutGet          uint64
+	GetDeviceInfo      uint64
+	LayoutCommit       uint64
+	LayoutReturn       uint64
+	SecinfoNoName      uint64
+	TestStateId        uint64
+	FreeStateId        uint64
+	GetDeviceList      uint64
+	BindConnToSession  uint64
+	DestroyClientId    uint64
+	Seek               uint64
+	Allocate           uint64
+	DeAllocate         uint64
+	LayoutStats        uint64
+	Clone              uint64
+}
+
+// ServerV4Stats models the nfsd "proc4" line.
+type ServerV4Stats struct {
+	Null     uint64
+	Compound uint64
+}
+
+// V4Ops models the "proc4ops" line: NFSv4 operations
+// Variable list, see:
+// v4.0 https://tools.ietf.org/html/rfc3010 (38 operations)
+// v4.1 https://tools.ietf.org/html/rfc5661 (58 operations)
+// v4.2 https://tools.ietf.org/html/draft-ietf-nfsv4-minorversion2-41 (71 operations)
+type V4Ops struct {
+	//Values       uint64 // Variable depending on v4.x sub-version. TODO: Will this always at least include the fields in this struct?
+	Op0Unused    uint64
+	Op1Unused    uint64
+	Op2Future    uint64
+	Access       uint64
+	Close        uint64
+	Commit       uint64
+	Create       uint64
+	DelegPurge   uint64
+	DelegReturn  uint64
+	GetAttr      uint64
+	GetFH        uint64
+	Link         uint64
+	Lock         uint64
+	Lockt        uint64
+	Locku        uint64
+	Lookup       uint64
+	LookupRoot   uint64
+	Nverify      uint64
+	Open         uint64
+	OpenAttr     uint64
+	OpenConfirm  uint64
+	OpenDgrd     uint64
+	PutFH        uint64
+	PutPubFH     uint64
+	PutRootFH    uint64
+	Read         uint64
+	ReadDir      uint64
+	ReadLink     uint64
+	Remove       uint64
+	Rename       uint64
+	Renew        uint64
+	RestoreFH    uint64
+	SaveFH       uint64
+	SecInfo      uint64
+	SetAttr      uint64
+	Verify       uint64
+	Write        uint64
+	RelLockOwner uint64
+}
+
+// RPCStats models all stats from /proc/net/rpc/nfs.
+type ClientRPCStats struct {
+	Network       Network
+	ClientRPC     ClientRPC
+	V2Stats       V2Stats
+	V3Stats       V3Stats
+	ClientV4Stats ClientV4Stats
+}
+
+// ServerRPCStats models all stats from /proc/net/rpc/nfsd.
+type ServerRPCStats struct {
+	ReplyCache     ReplyCache
+	FileHandles    FileHandles
+	InputOutput    InputOutput
+	Threads        Threads
+	ReadAheadCache ReadAheadCache
+	Network        Network
+	ServerRPC      ServerRPC
+	V2Stats        V2Stats
+	V3Stats        V3Stats
+	ServerV4Stats  ServerV4Stats
+	V4Ops          V4Ops
+}

vendor/github.com/prometheus/procfs/nfs/parse.go

@@ -0,0 +1,308 @@
+// Copyright 2018 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 nfs
+
+import (
+	"fmt"
+)
+
+func parseReplyCache(v []uint64) (ReplyCache, error) {
+	if len(v) != 3 {
+		return ReplyCache{}, fmt.Errorf("invalid ReplyCache line %q", v)
+	}
+
+	return ReplyCache{
+		Hits:    v[0],
+		Misses:  v[1],
+		NoCache: v[2],
+	}, nil
+}
+
+func parseFileHandles(v []uint64) (FileHandles, error) {
+	if len(v) != 5 {
+		return FileHandles{}, fmt.Errorf("invalid FileHandles, line %q", v)
+	}
+
+	return FileHandles{
+		Stale:        v[0],
+		TotalLookups: v[1],
+		AnonLookups:  v[2],
+		DirNoCache:   v[3],
+		NoDirNoCache: v[4],
+	}, nil
+}
+
+func parseInputOutput(v []uint64) (InputOutput, error) {
+	if len(v) != 2 {
+		return InputOutput{}, fmt.Errorf("invalid InputOutput line %q", v)
+	}
+
+	return InputOutput{
+		Read:  v[0],
+		Write: v[1],
+	}, nil
+}
+
+func parseThreads(v []uint64) (Threads, error) {
+	if len(v) != 2 {
+		return Threads{}, fmt.Errorf("invalid Threads line %q", v)
+	}
+
+	return Threads{
+		Threads: v[0],
+		FullCnt: v[1],
+	}, nil
+}
+
+func parseReadAheadCache(v []uint64) (ReadAheadCache, error) {
+	if len(v) != 12 {
+		return ReadAheadCache{}, fmt.Errorf("invalid ReadAheadCache line %q", v)
+	}
+
+	return ReadAheadCache{
+		CacheSize:      v[0],
+		CacheHistogram: v[1:11],
+		NotFound:       v[11],
+	}, nil
+}
+
+func parseNetwork(v []uint64) (Network, error) {
+	if len(v) != 4 {
+		return Network{}, fmt.Errorf("invalid Network line %q", v)
+	}
+
+	return Network{
+		NetCount:   v[0],
+		UDPCount:   v[1],
+		TCPCount:   v[2],
+		TCPConnect: v[3],
+	}, nil
+}
+
+func parseServerRPC(v []uint64) (ServerRPC, error) {
+	if len(v) != 5 {
+		return ServerRPC{}, fmt.Errorf("invalid RPC line %q", v)
+	}
+
+	return ServerRPC{
+		RPCCount: v[0],
+		BadCnt:   v[1],
+		BadFmt:   v[2],
+		BadAuth:  v[3],
+		BadcInt:  v[4],
+	}, nil
+}
+
+func parseClientRPC(v []uint64) (ClientRPC, error) {
+	if len(v) != 3 {
+		return ClientRPC{}, fmt.Errorf("invalid RPC line %q", v)
+	}
+
+	return ClientRPC{
+		RPCCount:        v[0],
+		Retransmissions: v[1],
+		AuthRefreshes:   v[2],
+	}, nil
+}
+
+func parseV2Stats(v []uint64) (V2Stats, error) {
+	values := int(v[0])
+	if len(v[1:]) != values || values != 18 {
+		return V2Stats{}, fmt.Errorf("invalid V2Stats line %q", v)
+	}
+
+	return V2Stats{
+		Null:     v[1],
+		GetAttr:  v[2],
+		SetAttr:  v[3],
+		Root:     v[4],
+		Lookup:   v[5],
+		ReadLink: v[6],
+		Read:     v[7],
+		WrCache:  v[8],
+		Write:    v[9],
+		Create:   v[10],
+		Remove:   v[11],
+		Rename:   v[12],
+		Link:     v[13],
+		SymLink:  v[14],
+		MkDir:    v[15],
+		RmDir:    v[16],
+		ReadDir:  v[17],
+		FsStat:   v[18],
+	}, nil
+}
+
+func parseV3Stats(v []uint64) (V3Stats, error) {
+	values := int(v[0])
+	if len(v[1:]) != values || values != 22 {
+		return V3Stats{}, fmt.Errorf("invalid V3Stats line %q", v)
+	}
+
+	return V3Stats{
+		Null:        v[1],
+		GetAttr:     v[2],
+		SetAttr:     v[3],
+		Lookup:      v[4],
+		Access:      v[5],
+		ReadLink:    v[6],
+		Read:        v[7],
+		Write:       v[8],
+		Create:      v[9],
+		MkDir:       v[10],
+		SymLink:     v[11],
+		MkNod:       v[12],
+		Remove:      v[13],
+		RmDir:       v[14],
+		Rename:      v[15],
+		Link:        v[16],
+		ReadDir:     v[17],
+		ReadDirPlus: v[18],
+		FsStat:      v[19],
+		FsInfo:      v[20],
+		PathConf:    v[21],
+		Commit:      v[22],
+	}, nil
+}
+
+func parseClientV4Stats(v []uint64) (ClientV4Stats, error) {
+	values := int(v[0])
+	if len(v[1:]) != values || values < 59 {
+		return ClientV4Stats{}, fmt.Errorf("invalid V4Stats line %q", v)
+	}
+
+	return ClientV4Stats{
+		Null:               v[1],
+		Read:               v[2],
+		Write:              v[3],
+		Commit:             v[4],
+		Open:               v[5],
+		OpenConfirm:        v[6],
+		OpenNoattr:         v[7],
+		OpenDowngrade:      v[8],
+		Close:              v[9],
+		Setattr:            v[10],
+		FsInfo:             v[11],
+		Renew:              v[12],
+		SetClientId:        v[13],
+		SetClientIdConfirm: v[14],
+		Lock:               v[15],
+		Lockt:              v[16],
+		Locku:              v[17],
+		Access:             v[18],
+		Getattr:            v[19],
+		Lookup:             v[20],
+		LookupRoot:         v[21],
+		Remove:             v[22],
+		Rename:             v[23],
+		Link:               v[24],
+		Symlink:            v[25],
+		Create:             v[26],
+		Pathconf:           v[27],
+		StatFs:             v[28],
+		ReadLink:           v[29],
+		ReadDir:            v[30],
+		ServerCaps:         v[31],
+		DelegReturn:        v[32],
+		GetAcl:             v[33],
+		SetAcl:             v[34],
+		FsLocations:        v[35],
+		ReleaseLockowner:   v[36],
+		Secinfo:            v[37],
+		FsidPresent:        v[38],
+		ExchangeId:         v[39],
+		CreateSession:      v[40],
+		DestroySession:     v[41],
+		Sequence:           v[42],
+		GetLeaseTime:       v[43],
+		ReclaimComplete:    v[44],
+		LayoutGet:          v[45],
+		GetDeviceInfo:      v[46],
+		LayoutCommit:       v[47],
+		LayoutReturn:       v[48],
+		SecinfoNoName:      v[49],
+		TestStateId:        v[50],
+		FreeStateId:        v[51],
+		GetDeviceList:      v[52],
+		BindConnToSession:  v[53],
+		DestroyClientId:    v[54],
+		Seek:               v[55],
+		Allocate:           v[56],
+		DeAllocate:         v[57],
+		LayoutStats:        v[58],
+		Clone:              v[59],
+	}, nil
+}
+
+func parseServerV4Stats(v []uint64) (ServerV4Stats, error) {
+	values := int(v[0])
+	if len(v[1:]) != values || values != 2 {
+		return ServerV4Stats{}, fmt.Errorf("invalid V4Stats line %q", v)
+	}
+
+	return ServerV4Stats{
+		Null:     v[1],
+		Compound: v[2],
+	}, nil
+}
+
+func parseV4Ops(v []uint64) (V4Ops, error) {
+	values := int(v[0])
+	if len(v[1:]) != values || values < 39 {
+		return V4Ops{}, fmt.Errorf("invalid V4Ops line %q", v)
+	}
+
+	stats := V4Ops{
+		Op0Unused:    v[1],
+		Op1Unused:    v[2],
+		Op2Future:    v[3],
+		Access:       v[4],
+		Close:        v[5],
+		Commit:       v[6],
+		Create:       v[7],
+		DelegPurge:   v[8],
+		DelegReturn:  v[9],
+		GetAttr:      v[10],
+		GetFH:        v[11],
+		Link:         v[12],
+		Lock:         v[13],
+		Lockt:        v[14],
+		Locku:        v[15],
+		Lookup:       v[16],
+		LookupRoot:   v[17],
+		Nverify:      v[18],
+		Open:         v[19],
+		OpenAttr:     v[20],
+		OpenConfirm:  v[21],
+		OpenDgrd:     v[22],
+		PutFH:        v[23],
+		PutPubFH:     v[24],
+		PutRootFH:    v[25],
+		Read:         v[26],
+		ReadDir:      v[27],
+		ReadLink:     v[28],
+		Remove:       v[29],
+		Rename:       v[30],
+		Renew:        v[31],
+		RestoreFH:    v[32],
+		SaveFH:       v[33],
+		SecInfo:      v[34],
+		SetAttr:      v[35],
+		Verify:       v[36],
+		Write:        v[37],
+		RelLockOwner: v[38],
+	}
+
+	return stats, nil
+}

vendor/github.com/prometheus/procfs/nfs/parse_nfs.go

@@ -0,0 +1,67 @@
+// Copyright 2018 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 nfs
+
+import (
+	"bufio"
+	"fmt"
+	"io"
+	"strings"
+
+	"github.com/prometheus/procfs/internal/util"
+)
+
+// ParseClientRPCStats returns stats read from /proc/net/rpc/nfs
+func ParseClientRPCStats(r io.Reader) (*ClientRPCStats, error) {
+	stats := &ClientRPCStats{}
+
+	scanner := bufio.NewScanner(r)
+	for scanner.Scan() {
+		line := scanner.Text()
+		parts := strings.Fields(scanner.Text())
+		// require at least <key> <value>
+		if len(parts) < 2 {
+			return nil, fmt.Errorf("invalid NFSd metric line %q", line)
+		}
+
+		values, err := util.ParseUint64s(parts[1:])
+		if err != nil {
+			return nil, fmt.Errorf("error parsing NFSd metric line: %s", err)
+		}
+
+		switch metricLine := parts[0]; metricLine {
+		case "net":
+			stats.Network, err = parseNetwork(values)
+		case "rpc":
+			stats.ClientRPC, err = parseClientRPC(values)
+		case "proc2":
+			stats.V2Stats, err = parseV2Stats(values)
+		case "proc3":
+			stats.V3Stats, err = parseV3Stats(values)
+		case "proc4":
+			stats.ClientV4Stats, err = parseClientV4Stats(values)
+		default:
+			return nil, fmt.Errorf("unknown NFSd metric line %q", metricLine)
+		}
+		if err != nil {
+			return nil, fmt.Errorf("errors parsing NFSd metric line: %s", err)
+		}
+	}
+
+	if err := scanner.Err(); err != nil {
+		return nil, fmt.Errorf("error scanning NFSd file: %s", err)
+	}
+
+	return stats, nil
+}

vendor/github.com/prometheus/procfs/nfs/parse_nfsd.go

@@ -0,0 +1,89 @@
+// Copyright 2018 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 nfs
+
+import (
+	"bufio"
+	"fmt"
+	"io"
+	"strings"
+
+	"github.com/prometheus/procfs/internal/util"
+)
+
+// ParseServerRPCStats returns stats read from /proc/net/rpc/nfsd
+func ParseServerRPCStats(r io.Reader) (*ServerRPCStats, error) {
+	stats := &ServerRPCStats{}
+
+	scanner := bufio.NewScanner(r)
+	for scanner.Scan() {
+		line := scanner.Text()
+		parts := strings.Fields(scanner.Text())
+		// require at least <key> <value>
+		if len(parts) < 2 {
+			return nil, fmt.Errorf("invalid NFSd metric line %q", line)
+		}
+		label := parts[0]
+
+		var values []uint64
+		var err error
+		if label == "th" {
+			if len(parts) < 3 {
+				return nil, fmt.Errorf("invalid NFSd th metric line %q", line)
+			}
+			values, err = util.ParseUint64s(parts[1:3])
+		} else {
+			values, err = util.ParseUint64s(parts[1:])
+		}
+		if err != nil {
+			return nil, fmt.Errorf("error parsing NFSd metric line: %s", err)
+		}
+
+		switch metricLine := parts[0]; metricLine {
+		case "rc":
+			stats.ReplyCache, err = parseReplyCache(values)
+		case "fh":
+			stats.FileHandles, err = parseFileHandles(values)
+		case "io":
+			stats.InputOutput, err = parseInputOutput(values)
+		case "th":
+			stats.Threads, err = parseThreads(values)
+		case "ra":
+			stats.ReadAheadCache, err = parseReadAheadCache(values)
+		case "net":
+			stats.Network, err = parseNetwork(values)
+		case "rpc":
+			stats.ServerRPC, err = parseServerRPC(values)
+		case "proc2":
+			stats.V2Stats, err = parseV2Stats(values)
+		case "proc3":
+			stats.V3Stats, err = parseV3Stats(values)
+		case "proc4":
+			stats.ServerV4Stats, err = parseServerV4Stats(values)
+		case "proc4ops":
+			stats.V4Ops, err = parseV4Ops(values)
+		default:
+			return nil, fmt.Errorf("unknown NFSd metric line %q", metricLine)
+		}
+		if err != nil {
+			return nil, fmt.Errorf("errors parsing NFSd metric line: %s", err)
+		}
+	}
+
+	if err := scanner.Err(); err != nil {
+		return nil, fmt.Errorf("error scanning NFSd file: %s", err)
+	}
+
+	return stats, nil
+}

vendor/github.com/prometheus/procfs/proc_io.go

@@ -47,9 +47,6 @@ func (p Proc) NewIO() (ProcIO, error) {
 
 	_, err = fmt.Sscanf(string(data), ioFormat, &pio.RChar, &pio.WChar, &pio.SyscR,
 		&pio.SyscW, &pio.ReadBytes, &pio.WriteBytes, &pio.CancelledWriteBytes)
-	if err != nil {
-		return pio, err
-	}
 
-	return pio, nil
+	return pio, err
 }

vendor/github.com/prometheus/procfs/proc_limits.go

@@ -13,46 +13,46 @@ import (
 // http://man7.org/linux/man-pages/man2/getrlimit.2.html.
 type ProcLimits struct {
 	// CPU time limit in seconds.
-	CPUTime int
+	CPUTime int64
 	// Maximum size of files that the process may create.
-	FileSize int
+	FileSize int64
 	// Maximum size of the process's data segment (initialized data,
 	// uninitialized data, and heap).
-	DataSize int
+	DataSize int64
 	// Maximum size of the process stack in bytes.
-	StackSize int
+	StackSize int64
 	// Maximum size of a core file.
-	CoreFileSize int
+	CoreFileSize int64
 	// Limit of the process's resident set in pages.
-	ResidentSet int
+	ResidentSet int64
 	// Maximum number of processes that can be created for the real user ID of
 	// the calling process.
-	Processes int
+	Processes int64
 	// Value one greater than the maximum file descriptor number that can be
 	// opened by this process.
-	OpenFiles int
+	OpenFiles int64
 	// Maximum number of bytes of memory that may be locked into RAM.
-	LockedMemory int
+	LockedMemory int64
 	// Maximum size of the process's virtual memory address space in bytes.
-	AddressSpace int
+	AddressSpace int64
 	// Limit on the combined number of flock(2) locks and fcntl(2) leases that
 	// this process may establish.
-	FileLocks int
+	FileLocks int64
 	// Limit of signals that may be queued for the real user ID of the calling
 	// process.
-	PendingSignals int
+	PendingSignals int64
 	// Limit on the number of bytes that can be allocated for POSIX message
 	// queues for the real user ID of the calling process.
-	MsqqueueSize int
+	MsqqueueSize int64
 	// Limit of the nice priority set using setpriority(2) or nice(2).
-	NicePriority int
+	NicePriority int64
 	// Limit of the real-time priority set using sched_setscheduler(2) or
 	// sched_setparam(2).
-	RealtimePriority int
+	RealtimePriority int64
 	// Limit (in microseconds) on the amount of CPU time that a process
 	// scheduled under a real-time scheduling policy may consume without making
 	// a blocking system call.
-	RealtimeTimeout int
+	RealtimeTimeout int64
 }
 
 const (
@@ -125,13 +125,13 @@ func (p Proc) NewLimits() (ProcLimits, error) {
 	return l, s.Err()
 }
 
-func parseInt(s string) (int, error) {
+func parseInt(s string) (int64, error) {
 	if s == limitsUnlimited {
 		return -1, nil
 	}
-	i, err := strconv.ParseInt(s, 10, 32)
+	i, err := strconv.ParseInt(s, 10, 64)
 	if err != nil {
 		return 0, fmt.Errorf("couldn't parse value %s: %s", s, err)
 	}
-	return int(i), nil
+	return i, nil
 }

vendor/github.com/prometheus/procfs/proc_ns.go

@@ -0,0 +1,55 @@
+package procfs
+
+import (
+	"fmt"
+	"os"
+	"strconv"
+	"strings"
+)
+
+// Namespace represents a single namespace of a process.
+type Namespace struct {
+	Type  string // Namespace type.
+	Inode uint32 // Inode number of the namespace. If two processes are in the same namespace their inodes will match.
+}
+
+// Namespaces contains all of the namespaces that the process is contained in.
+type Namespaces map[string]Namespace
+
+// NewNamespaces reads from /proc/[pid/ns/* to get the namespaces of which the
+// process is a member.
+func (p Proc) NewNamespaces() (Namespaces, error) {
+	d, err := os.Open(p.path("ns"))
+	if err != nil {
+		return nil, err
+	}
+	defer d.Close()
+
+	names, err := d.Readdirnames(-1)
+	if err != nil {
+		return nil, fmt.Errorf("failed to read contents of ns dir: %v", err)
+	}
+
+	ns := make(Namespaces, len(names))
+	for _, name := range names {
+		target, err := os.Readlink(p.path("ns", name))
+		if err != nil {
+			return nil, err
+		}
+
+		fields := strings.SplitN(target, ":", 2)
+		if len(fields) != 2 {
+			return nil, fmt.Errorf("failed to parse namespace type and inode from '%v'", target)
+		}
+
+		typ := fields[0]
+		inode, err := strconv.ParseUint(strings.Trim(fields[1], "[]"), 10, 32)
+		if err != nil {
+			return nil, fmt.Errorf("failed to parse inode from '%v': %v", fields[1], err)
+		}
+
+		ns[name] = Namespace{typ, uint32(inode)}
+	}
+
+	return ns, nil
+}

vendor/github.com/prometheus/procfs/stat.go

@@ -3,15 +3,66 @@ package procfs
 import (
 	"bufio"
 	"fmt"
+	"io"
 	"os"
 	"strconv"
 	"strings"
 )
 
+// CPUStat shows how much time the cpu spend in various stages.
+type CPUStat struct {
+	User      float64
+	Nice      float64
+	System    float64
+	Idle      float64
+	Iowait    float64
+	IRQ       float64
+	SoftIRQ   float64
+	Steal     float64
+	Guest     float64
+	GuestNice float64
+}
+
+// SoftIRQStat represent the softirq statistics as exported in the procfs stat file.
+// A nice introduction can be found at https://0xax.gitbooks.io/linux-insides/content/interrupts/interrupts-9.html
+// It is possible to get per-cpu stats by reading /proc/softirqs
+type SoftIRQStat struct {
+	Hi          uint64
+	Timer       uint64
+	NetTx       uint64
+	NetRx       uint64
+	Block       uint64
+	BlockIoPoll uint64
+	Tasklet     uint64
+	Sched       uint64
+	Hrtimer     uint64
+	Rcu         uint64
+}
+
 // Stat represents kernel/system statistics.
 type Stat struct {
 	// Boot time in seconds since the Epoch.
-	BootTime int64
+	BootTime uint64
+	// Summed up cpu statistics.
+	CPUTotal CPUStat
+	// Per-CPU statistics.
+	CPU []CPUStat
+	// Number of times interrupts were handled, which contains numbered and unnumbered IRQs.
+	IRQTotal uint64
+	// Number of times a numbered IRQ was triggered.
+	IRQ []uint64
+	// Number of times a context switch happened.
+	ContextSwitches uint64
+	// Number of times a process was created.
+	ProcessCreated uint64
+	// Number of processes currently running.
+	ProcessesRunning uint64
+	// Number of processes currently blocked (waiting for IO).
+	ProcessesBlocked uint64
+	// Number of times a softirq was scheduled.
+	SoftIRQTotal uint64
+	// Detailed softirq statistics.
+	SoftIRQ SoftIRQStat
 }
 
 // NewStat returns kernel/system statistics read from /proc/stat.
@@ -24,33 +75,145 @@ func NewStat() (Stat, error) {
 	return fs.NewStat()
 }
 
+// Parse a cpu statistics line and returns the CPUStat struct plus the cpu id (or -1 for the overall sum).
+func parseCPUStat(line string) (CPUStat, int64, error) {
+	cpuStat := CPUStat{}
+	var cpu string
+
+	count, err := fmt.Sscanf(line, "%s %f %f %f %f %f %f %f %f %f %f",
+		&cpu,
+		&cpuStat.User, &cpuStat.Nice, &cpuStat.System, &cpuStat.Idle,
+		&cpuStat.Iowait, &cpuStat.IRQ, &cpuStat.SoftIRQ, &cpuStat.Steal,
+		&cpuStat.Guest, &cpuStat.GuestNice)
+
+	if err != nil && err != io.EOF {
+		return CPUStat{}, -1, fmt.Errorf("couldn't parse %s (cpu): %s", line, err)
+	}
+	if count == 0 {
+		return CPUStat{}, -1, fmt.Errorf("couldn't parse %s (cpu): 0 elements parsed", line)
+	}
+
+	cpuStat.User /= userHZ
+	cpuStat.Nice /= userHZ
+	cpuStat.System /= userHZ
+	cpuStat.Idle /= userHZ
+	cpuStat.Iowait /= userHZ
+	cpuStat.IRQ /= userHZ
+	cpuStat.SoftIRQ /= userHZ
+	cpuStat.Steal /= userHZ
+	cpuStat.Guest /= userHZ
+	cpuStat.GuestNice /= userHZ
+
+	if cpu == "cpu" {
+		return cpuStat, -1, nil
+	}
+
+	cpuID, err := strconv.ParseInt(cpu[3:], 10, 64)
+	if err != nil {
+		return CPUStat{}, -1, fmt.Errorf("couldn't parse %s (cpu/cpuid): %s", line, err)
+	}
+
+	return cpuStat, cpuID, nil
+}
+
+// Parse a softirq line.
+func parseSoftIRQStat(line string) (SoftIRQStat, uint64, error) {
+	softIRQStat := SoftIRQStat{}
+	var total uint64
+	var prefix string
+
+	_, err := fmt.Sscanf(line, "%s %d %d %d %d %d %d %d %d %d %d %d",
+		&prefix, &total,
+		&softIRQStat.Hi, &softIRQStat.Timer, &softIRQStat.NetTx, &softIRQStat.NetRx,
+		&softIRQStat.Block, &softIRQStat.BlockIoPoll,
+		&softIRQStat.Tasklet, &softIRQStat.Sched,
+		&softIRQStat.Hrtimer, &softIRQStat.Rcu)
+
+	if err != nil {
+		return SoftIRQStat{}, 0, fmt.Errorf("couldn't parse %s (softirq): %s", line, err)
+	}
+
+	return softIRQStat, total, nil
+}
+
 // NewStat returns an information about current kernel/system statistics.
 func (fs FS) NewStat() (Stat, error) {
+	// See https://www.kernel.org/doc/Documentation/filesystems/proc.txt
+
 	f, err := os.Open(fs.Path("stat"))
 	if err != nil {
 		return Stat{}, err
 	}
 	defer f.Close()
 
-	s := bufio.NewScanner(f)
+	stat := Stat{}
-	for s.Scan() {
+
-		line := s.Text()
+	scanner := bufio.NewScanner(f)
-		if !strings.HasPrefix(line, "btime") {
+	for scanner.Scan() {
+		line := scanner.Text()
+		parts := strings.Fields(scanner.Text())
+		// require at least <key> <value>
+		if len(parts) < 2 {
 			continue
 		}
-		fields := strings.Fields(line)
+		switch {
-		if len(fields) != 2 {
+		case parts[0] == "btime":
-			return Stat{}, fmt.Errorf("couldn't parse %s line %s", f.Name(), line)
+			if stat.BootTime, err = strconv.ParseUint(parts[1], 10, 64); err != nil {
+				return Stat{}, fmt.Errorf("couldn't parse %s (btime): %s", parts[1], err)
+			}
+		case parts[0] == "intr":
+			if stat.IRQTotal, err = strconv.ParseUint(parts[1], 10, 64); err != nil {
+				return Stat{}, fmt.Errorf("couldn't parse %s (intr): %s", parts[1], err)
+			}
+			numberedIRQs := parts[2:]
+			stat.IRQ = make([]uint64, len(numberedIRQs))
+			for i, count := range numberedIRQs {
+				if stat.IRQ[i], err = strconv.ParseUint(count, 10, 64); err != nil {
+					return Stat{}, fmt.Errorf("couldn't parse %s (intr%d): %s", count, i, err)
+				}
+			}
+		case parts[0] == "ctxt":
+			if stat.ContextSwitches, err = strconv.ParseUint(parts[1], 10, 64); err != nil {
+				return Stat{}, fmt.Errorf("couldn't parse %s (ctxt): %s", parts[1], err)
+			}
+		case parts[0] == "processes":
+			if stat.ProcessCreated, err = strconv.ParseUint(parts[1], 10, 64); err != nil {
+				return Stat{}, fmt.Errorf("couldn't parse %s (processes): %s", parts[1], err)
+			}
+		case parts[0] == "procs_running":
+			if stat.ProcessesRunning, err = strconv.ParseUint(parts[1], 10, 64); err != nil {
+				return Stat{}, fmt.Errorf("couldn't parse %s (procs_running): %s", parts[1], err)
+			}
+		case parts[0] == "procs_blocked":
+			if stat.ProcessesBlocked, err = strconv.ParseUint(parts[1], 10, 64); err != nil {
+				return Stat{}, fmt.Errorf("couldn't parse %s (procs_blocked): %s", parts[1], err)
+			}
+		case parts[0] == "softirq":
+			softIRQStats, total, err := parseSoftIRQStat(line)
+			if err != nil {
+				return Stat{}, err
+			}
+			stat.SoftIRQTotal = total
+			stat.SoftIRQ = softIRQStats
+		case strings.HasPrefix(parts[0], "cpu"):
+			cpuStat, cpuID, err := parseCPUStat(line)
+			if err != nil {
+				return Stat{}, err
+			}
+			if cpuID == -1 {
+				stat.CPUTotal = cpuStat
+			} else {
+				for int64(len(stat.CPU)) <= cpuID {
+					stat.CPU = append(stat.CPU, CPUStat{})
+				}
+				stat.CPU[cpuID] = cpuStat
+			}
 		}
-		i, err := strconv.ParseInt(fields[1], 10, 32)
-		if err != nil {
-			return Stat{}, fmt.Errorf("couldn't parse %s: %s", fields[1], err)
-		}
-		return Stat{BootTime: i}, nil
 	}
-	if err := s.Err(); err != nil {
+
+	if err := scanner.Err(); err != nil {
 		return Stat{}, fmt.Errorf("couldn't parse %s: %s", f.Name(), err)
 	}
 
-	return Stat{}, fmt.Errorf("couldn't parse %s, missing btime", f.Name())
+	return stat, nil
 }

vendor/github.com/prometheus/procfs/xfrm.go

@@ -0,0 +1,187 @@
+// Copyright 2017 Prometheus Team
+// 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 procfs
+
+import (
+	"bufio"
+	"fmt"
+	"os"
+	"strconv"
+	"strings"
+)
+
+// XfrmStat models the contents of /proc/net/xfrm_stat.
+type XfrmStat struct {
+	// All errors which are not matched by other
+	XfrmInError int
+	// No buffer is left
+	XfrmInBufferError int
+	// Header Error
+	XfrmInHdrError int
+	// No state found
+	// i.e. either inbound SPI, address, or IPSEC protocol at SA is wrong
+	XfrmInNoStates int
+	// Transformation protocol specific error
+	// e.g. SA Key is wrong
+	XfrmInStateProtoError int
+	// Transformation mode specific error
+	XfrmInStateModeError int
+	// Sequence error
+	// e.g. sequence number is out of window
+	XfrmInStateSeqError int
+	// State is expired
+	XfrmInStateExpired int
+	// State has mismatch option
+	// e.g. UDP encapsulation type is mismatched
+	XfrmInStateMismatch int
+	// State is invalid
+	XfrmInStateInvalid int
+	// No matching template for states
+	// e.g. Inbound SAs are correct but SP rule is wrong
+	XfrmInTmplMismatch int
+	// No policy is found for states
+	// e.g. Inbound SAs are correct but no SP is found
+	XfrmInNoPols int
+	// Policy discards
+	XfrmInPolBlock int
+	// Policy error
+	XfrmInPolError int
+	// All errors which are not matched by others
+	XfrmOutError int
+	// Bundle generation error
+	XfrmOutBundleGenError int
+	// Bundle check error
+	XfrmOutBundleCheckError int
+	// No state was found
+	XfrmOutNoStates int
+	// Transformation protocol specific error
+	XfrmOutStateProtoError int
+	// Transportation mode specific error
+	XfrmOutStateModeError int
+	// Sequence error
+	// i.e sequence number overflow
+	XfrmOutStateSeqError int
+	// State is expired
+	XfrmOutStateExpired int
+	// Policy discads
+	XfrmOutPolBlock int
+	// Policy is dead
+	XfrmOutPolDead int
+	// Policy Error
+	XfrmOutPolError     int
+	XfrmFwdHdrError     int
+	XfrmOutStateInvalid int
+	XfrmAcquireError    int
+}
+
+// NewXfrmStat reads the xfrm_stat statistics.
+func NewXfrmStat() (XfrmStat, error) {
+	fs, err := NewFS(DefaultMountPoint)
+	if err != nil {
+		return XfrmStat{}, err
+	}
+
+	return fs.NewXfrmStat()
+}
+
+// NewXfrmStat reads the xfrm_stat statistics from the 'proc' filesystem.
+func (fs FS) NewXfrmStat() (XfrmStat, error) {
+	file, err := os.Open(fs.Path("net/xfrm_stat"))
+	if err != nil {
+		return XfrmStat{}, err
+	}
+	defer file.Close()
+
+	var (
+		x = XfrmStat{}
+		s = bufio.NewScanner(file)
+	)
+
+	for s.Scan() {
+		fields := strings.Fields(s.Text())
+
+		if len(fields) != 2 {
+			return XfrmStat{}, fmt.Errorf(
+				"couldnt parse %s line %s", file.Name(), s.Text())
+		}
+
+		name := fields[0]
+		value, err := strconv.Atoi(fields[1])
+		if err != nil {
+			return XfrmStat{}, err
+		}
+
+		switch name {
+		case "XfrmInError":
+			x.XfrmInError = value
+		case "XfrmInBufferError":
+			x.XfrmInBufferError = value
+		case "XfrmInHdrError":
+			x.XfrmInHdrError = value
+		case "XfrmInNoStates":
+			x.XfrmInNoStates = value
+		case "XfrmInStateProtoError":
+			x.XfrmInStateProtoError = value
+		case "XfrmInStateModeError":
+			x.XfrmInStateModeError = value
+		case "XfrmInStateSeqError":
+			x.XfrmInStateSeqError = value
+		case "XfrmInStateExpired":
+			x.XfrmInStateExpired = value
+		case "XfrmInStateInvalid":
+			x.XfrmInStateInvalid = value
+		case "XfrmInTmplMismatch":
+			x.XfrmInTmplMismatch = value
+		case "XfrmInNoPols":
+			x.XfrmInNoPols = value
+		case "XfrmInPolBlock":
+			x.XfrmInPolBlock = value
+		case "XfrmInPolError":
+			x.XfrmInPolError = value
+		case "XfrmOutError":
+			x.XfrmOutError = value
+		case "XfrmInStateMismatch":
+			x.XfrmInStateMismatch = value
+		case "XfrmOutBundleGenError":
+			x.XfrmOutBundleGenError = value
+		case "XfrmOutBundleCheckError":
+			x.XfrmOutBundleCheckError = value
+		case "XfrmOutNoStates":
+			x.XfrmOutNoStates = value
+		case "XfrmOutStateProtoError":
+			x.XfrmOutStateProtoError = value
+		case "XfrmOutStateModeError":
+			x.XfrmOutStateModeError = value
+		case "XfrmOutStateSeqError":
+			x.XfrmOutStateSeqError = value
+		case "XfrmOutStateExpired":
+			x.XfrmOutStateExpired = value
+		case "XfrmOutPolBlock":
+			x.XfrmOutPolBlock = value
+		case "XfrmOutPolDead":
+			x.XfrmOutPolDead = value
+		case "XfrmOutPolError":
+			x.XfrmOutPolError = value
+		case "XfrmFwdHdrError":
+			x.XfrmFwdHdrError = value
+		case "XfrmOutStateInvalid":
+			x.XfrmOutStateInvalid = value
+		case "XfrmAcquireError":
+			x.XfrmAcquireError = value
+		}
+
+	}
+
+	return x, s.Err()
+}

vendor/github.com/prometheus/procfs/xfs/parse.go

@@ -0,0 +1,330 @@
+// 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 xfs
+
+import (
+	"bufio"
+	"fmt"
+	"io"
+	"strings"
+
+	"github.com/prometheus/procfs/internal/util"
+)
+
+// ParseStats parses a Stats from an input io.Reader, using the format
+// found in /proc/fs/xfs/stat.
+func ParseStats(r io.Reader) (*Stats, error) {
+	const (
+		// Fields parsed into stats structures.
+		fieldExtentAlloc = "extent_alloc"
+		fieldAbt         = "abt"
+		fieldBlkMap      = "blk_map"
+		fieldBmbt        = "bmbt"
+		fieldDir         = "dir"
+		fieldTrans       = "trans"
+		fieldIg          = "ig"
+		fieldLog         = "log"
+		fieldRw          = "rw"
+		fieldAttr        = "attr"
+		fieldIcluster    = "icluster"
+		fieldVnodes      = "vnodes"
+		fieldBuf         = "buf"
+		fieldXpc         = "xpc"
+
+		// Unimplemented at this time due to lack of documentation.
+		fieldPushAil = "push_ail"
+		fieldXstrat  = "xstrat"
+		fieldAbtb2   = "abtb2"
+		fieldAbtc2   = "abtc2"
+		fieldBmbt2   = "bmbt2"
+		fieldIbt2    = "ibt2"
+		fieldFibt2   = "fibt2"
+		fieldQm      = "qm"
+		fieldDebug   = "debug"
+	)
+
+	var xfss Stats
+
+	s := bufio.NewScanner(r)
+	for s.Scan() {
+		// Expect at least a string label and a single integer value, ex:
+		//   - abt 0
+		//   - rw 1 2
+		ss := strings.Fields(string(s.Bytes()))
+		if len(ss) < 2 {
+			continue
+		}
+		label := ss[0]
+
+		// Extended precision counters are uint64 values.
+		if label == fieldXpc {
+			us, err := util.ParseUint64s(ss[1:])
+			if err != nil {
+				return nil, err
+			}
+
+			xfss.ExtendedPrecision, err = extendedPrecisionStats(us)
+			if err != nil {
+				return nil, err
+			}
+
+			continue
+		}
+
+		// All other counters are uint32 values.
+		us, err := util.ParseUint32s(ss[1:])
+		if err != nil {
+			return nil, err
+		}
+
+		switch label {
+		case fieldExtentAlloc:
+			xfss.ExtentAllocation, err = extentAllocationStats(us)
+		case fieldAbt:
+			xfss.AllocationBTree, err = btreeStats(us)
+		case fieldBlkMap:
+			xfss.BlockMapping, err = blockMappingStats(us)
+		case fieldBmbt:
+			xfss.BlockMapBTree, err = btreeStats(us)
+		case fieldDir:
+			xfss.DirectoryOperation, err = directoryOperationStats(us)
+		case fieldTrans:
+			xfss.Transaction, err = transactionStats(us)
+		case fieldIg:
+			xfss.InodeOperation, err = inodeOperationStats(us)
+		case fieldLog:
+			xfss.LogOperation, err = logOperationStats(us)
+		case fieldRw:
+			xfss.ReadWrite, err = readWriteStats(us)
+		case fieldAttr:
+			xfss.AttributeOperation, err = attributeOperationStats(us)
+		case fieldIcluster:
+			xfss.InodeClustering, err = inodeClusteringStats(us)
+		case fieldVnodes:
+			xfss.Vnode, err = vnodeStats(us)
+		case fieldBuf:
+			xfss.Buffer, err = bufferStats(us)
+		}
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	return &xfss, s.Err()
+}
+
+// extentAllocationStats builds an ExtentAllocationStats from a slice of uint32s.
+func extentAllocationStats(us []uint32) (ExtentAllocationStats, error) {
+	if l := len(us); l != 4 {
+		return ExtentAllocationStats{}, fmt.Errorf("incorrect number of values for XFS extent allocation stats: %d", l)
+	}
+
+	return ExtentAllocationStats{
+		ExtentsAllocated: us[0],
+		BlocksAllocated:  us[1],
+		ExtentsFreed:     us[2],
+		BlocksFreed:      us[3],
+	}, nil
+}
+
+// btreeStats builds a BTreeStats from a slice of uint32s.
+func btreeStats(us []uint32) (BTreeStats, error) {
+	if l := len(us); l != 4 {
+		return BTreeStats{}, fmt.Errorf("incorrect number of values for XFS btree stats: %d", l)
+	}
+
+	return BTreeStats{
+		Lookups:         us[0],
+		Compares:        us[1],
+		RecordsInserted: us[2],
+		RecordsDeleted:  us[3],
+	}, nil
+}
+
+// BlockMappingStat builds a BlockMappingStats from a slice of uint32s.
+func blockMappingStats(us []uint32) (BlockMappingStats, error) {
+	if l := len(us); l != 7 {
+		return BlockMappingStats{}, fmt.Errorf("incorrect number of values for XFS block mapping stats: %d", l)
+	}
+
+	return BlockMappingStats{
+		Reads:                us[0],
+		Writes:               us[1],
+		Unmaps:               us[2],
+		ExtentListInsertions: us[3],
+		ExtentListDeletions:  us[4],
+		ExtentListLookups:    us[5],
+		ExtentListCompares:   us[6],
+	}, nil
+}
+
+// DirectoryOperationStats builds a DirectoryOperationStats from a slice of uint32s.
+func directoryOperationStats(us []uint32) (DirectoryOperationStats, error) {
+	if l := len(us); l != 4 {
+		return DirectoryOperationStats{}, fmt.Errorf("incorrect number of values for XFS directory operation stats: %d", l)
+	}
+
+	return DirectoryOperationStats{
+		Lookups:  us[0],
+		Creates:  us[1],
+		Removes:  us[2],
+		Getdents: us[3],
+	}, nil
+}
+
+// TransactionStats builds a TransactionStats from a slice of uint32s.
+func transactionStats(us []uint32) (TransactionStats, error) {
+	if l := len(us); l != 3 {
+		return TransactionStats{}, fmt.Errorf("incorrect number of values for XFS transaction stats: %d", l)
+	}
+
+	return TransactionStats{
+		Sync:  us[0],
+		Async: us[1],
+		Empty: us[2],
+	}, nil
+}
+
+// InodeOperationStats builds an InodeOperationStats from a slice of uint32s.
+func inodeOperationStats(us []uint32) (InodeOperationStats, error) {
+	if l := len(us); l != 7 {
+		return InodeOperationStats{}, fmt.Errorf("incorrect number of values for XFS inode operation stats: %d", l)
+	}
+
+	return InodeOperationStats{
+		Attempts:        us[0],
+		Found:           us[1],
+		Recycle:         us[2],
+		Missed:          us[3],
+		Duplicate:       us[4],
+		Reclaims:        us[5],
+		AttributeChange: us[6],
+	}, nil
+}
+
+// LogOperationStats builds a LogOperationStats from a slice of uint32s.
+func logOperationStats(us []uint32) (LogOperationStats, error) {
+	if l := len(us); l != 5 {
+		return LogOperationStats{}, fmt.Errorf("incorrect number of values for XFS log operation stats: %d", l)
+	}
+
+	return LogOperationStats{
+		Writes:            us[0],
+		Blocks:            us[1],
+		NoInternalBuffers: us[2],
+		Force:             us[3],
+		ForceSleep:        us[4],
+	}, nil
+}
+
+// ReadWriteStats builds a ReadWriteStats from a slice of uint32s.
+func readWriteStats(us []uint32) (ReadWriteStats, error) {
+	if l := len(us); l != 2 {
+		return ReadWriteStats{}, fmt.Errorf("incorrect number of values for XFS read write stats: %d", l)
+	}
+
+	return ReadWriteStats{
+		Read:  us[0],
+		Write: us[1],
+	}, nil
+}
+
+// AttributeOperationStats builds an AttributeOperationStats from a slice of uint32s.
+func attributeOperationStats(us []uint32) (AttributeOperationStats, error) {
+	if l := len(us); l != 4 {
+		return AttributeOperationStats{}, fmt.Errorf("incorrect number of values for XFS attribute operation stats: %d", l)
+	}
+
+	return AttributeOperationStats{
+		Get:    us[0],
+		Set:    us[1],
+		Remove: us[2],
+		List:   us[3],
+	}, nil
+}
+
+// InodeClusteringStats builds an InodeClusteringStats from a slice of uint32s.
+func inodeClusteringStats(us []uint32) (InodeClusteringStats, error) {
+	if l := len(us); l != 3 {
+		return InodeClusteringStats{}, fmt.Errorf("incorrect number of values for XFS inode clustering stats: %d", l)
+	}
+
+	return InodeClusteringStats{
+		Iflush:     us[0],
+		Flush:      us[1],
+		FlushInode: us[2],
+	}, nil
+}
+
+// VnodeStats builds a VnodeStats from a slice of uint32s.
+func vnodeStats(us []uint32) (VnodeStats, error) {
+	// The attribute "Free" appears to not be available on older XFS
+	// stats versions.  Therefore, 7 or 8 elements may appear in
+	// this slice.
+	l := len(us)
+	if l != 7 && l != 8 {
+		return VnodeStats{}, fmt.Errorf("incorrect number of values for XFS vnode stats: %d", l)
+	}
+
+	s := VnodeStats{
+		Active:   us[0],
+		Allocate: us[1],
+		Get:      us[2],
+		Hold:     us[3],
+		Release:  us[4],
+		Reclaim:  us[5],
+		Remove:   us[6],
+	}
+
+	// Skip adding free, unless it is present. The zero value will
+	// be used in place of an actual count.
+	if l == 7 {
+		return s, nil
+	}
+
+	s.Free = us[7]
+	return s, nil
+}
+
+// BufferStats builds a BufferStats from a slice of uint32s.
+func bufferStats(us []uint32) (BufferStats, error) {
+	if l := len(us); l != 9 {
+		return BufferStats{}, fmt.Errorf("incorrect number of values for XFS buffer stats: %d", l)
+	}
+
+	return BufferStats{
+		Get:             us[0],
+		Create:          us[1],
+		GetLocked:       us[2],
+		GetLockedWaited: us[3],
+		BusyLocked:      us[4],
+		MissLocked:      us[5],
+		PageRetries:     us[6],
+		PageFound:       us[7],
+		GetRead:         us[8],
+	}, nil
+}
+
+// ExtendedPrecisionStats builds an ExtendedPrecisionStats from a slice of uint32s.
+func extendedPrecisionStats(us []uint64) (ExtendedPrecisionStats, error) {
+	if l := len(us); l != 3 {
+		return ExtendedPrecisionStats{}, fmt.Errorf("incorrect number of values for XFS extended precision stats: %d", l)
+	}
+
+	return ExtendedPrecisionStats{
+		FlushBytes: us[0],
+		WriteBytes: us[1],
+		ReadBytes:  us[2],
+	}, nil
+}

vendor/github.com/prometheus/procfs/xfs/xfs.go

@@ -0,0 +1,163 @@
+// 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 xfs provides access to statistics exposed by the XFS filesystem.
+package xfs
+
+// Stats contains XFS filesystem runtime statistics, parsed from
+// /proc/fs/xfs/stat.
+//
+// The names and meanings of each statistic were taken from
+// http://xfs.org/index.php/Runtime_Stats and xfs_stats.h in the Linux
+// kernel source. Most counters are uint32s (same data types used in
+// xfs_stats.h), but some of the "extended precision stats" are uint64s.
+type Stats struct {
+	// The name of the filesystem used to source these statistics.
+	// If empty, this indicates aggregated statistics for all XFS
+	// filesystems on the host.
+	Name string
+
+	ExtentAllocation   ExtentAllocationStats
+	AllocationBTree    BTreeStats
+	BlockMapping       BlockMappingStats
+	BlockMapBTree      BTreeStats
+	DirectoryOperation DirectoryOperationStats
+	Transaction        TransactionStats
+	InodeOperation     InodeOperationStats
+	LogOperation       LogOperationStats
+	ReadWrite          ReadWriteStats
+	AttributeOperation AttributeOperationStats
+	InodeClustering    InodeClusteringStats
+	Vnode              VnodeStats
+	Buffer             BufferStats
+	ExtendedPrecision  ExtendedPrecisionStats
+}
+
+// ExtentAllocationStats contains statistics regarding XFS extent allocations.
+type ExtentAllocationStats struct {
+	ExtentsAllocated uint32
+	BlocksAllocated  uint32
+	ExtentsFreed     uint32
+	BlocksFreed      uint32
+}
+
+// BTreeStats contains statistics regarding an XFS internal B-tree.
+type BTreeStats struct {
+	Lookups         uint32
+	Compares        uint32
+	RecordsInserted uint32
+	RecordsDeleted  uint32
+}
+
+// BlockMappingStats contains statistics regarding XFS block maps.
+type BlockMappingStats struct {
+	Reads                uint32
+	Writes               uint32
+	Unmaps               uint32
+	ExtentListInsertions uint32
+	ExtentListDeletions  uint32
+	ExtentListLookups    uint32
+	ExtentListCompares   uint32
+}
+
+// DirectoryOperationStats contains statistics regarding XFS directory entries.
+type DirectoryOperationStats struct {
+	Lookups  uint32
+	Creates  uint32
+	Removes  uint32
+	Getdents uint32
+}
+
+// TransactionStats contains statistics regarding XFS metadata transactions.
+type TransactionStats struct {
+	Sync  uint32
+	Async uint32
+	Empty uint32
+}
+
+// InodeOperationStats contains statistics regarding XFS inode operations.
+type InodeOperationStats struct {
+	Attempts        uint32
+	Found           uint32
+	Recycle         uint32
+	Missed          uint32
+	Duplicate       uint32
+	Reclaims        uint32
+	AttributeChange uint32
+}
+
+// LogOperationStats contains statistics regarding the XFS log buffer.
+type LogOperationStats struct {
+	Writes            uint32
+	Blocks            uint32
+	NoInternalBuffers uint32
+	Force             uint32
+	ForceSleep        uint32
+}
+
+// ReadWriteStats contains statistics regarding the number of read and write
+// system calls for XFS filesystems.
+type ReadWriteStats struct {
+	Read  uint32
+	Write uint32
+}
+
+// AttributeOperationStats contains statistics regarding manipulation of
+// XFS extended file attributes.
+type AttributeOperationStats struct {
+	Get    uint32
+	Set    uint32
+	Remove uint32
+	List   uint32
+}
+
+// InodeClusteringStats contains statistics regarding XFS inode clustering
+// operations.
+type InodeClusteringStats struct {
+	Iflush     uint32
+	Flush      uint32
+	FlushInode uint32
+}
+
+// VnodeStats contains statistics regarding XFS vnode operations.
+type VnodeStats struct {
+	Active   uint32
+	Allocate uint32
+	Get      uint32
+	Hold     uint32
+	Release  uint32
+	Reclaim  uint32
+	Remove   uint32
+	Free     uint32
+}
+
+// BufferStats contains statistics regarding XFS read/write I/O buffers.
+type BufferStats struct {
+	Get             uint32
+	Create          uint32
+	GetLocked       uint32
+	GetLockedWaited uint32
+	BusyLocked      uint32
+	MissLocked      uint32
+	PageRetries     uint32
+	PageFound       uint32
+	GetRead         uint32
+}
+
+// ExtendedPrecisionStats contains high precision counters used to track the
+// total number of bytes read, written, or flushed, during XFS operations.
+type ExtendedPrecisionStats struct {
+	FlushBytes uint64
+	WriteBytes uint64
+	ReadBytes  uint64
+}