vendoring: Update client_golang/prometheus

This is mostly required to enable summaries without quantiles

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

@@ -30,16 +30,8 @@ type Counter interface {
 	Metric
 	Collector
 
-	// Set is used to set the Counter to an arbitrary value. It is only used
-	// if you have to transfer a value from an external counter into this
-	// Prometheus metric. Do not use it for regular handling of a
-	// Prometheus counter (as it can be used to break the contract of
-	// monotonically increasing values).
-	//
-	// Deprecated: Use NewConstMetric to create a counter for an external
-	// value. A Counter should never be set.
-	Set(float64)
-	// Inc increments the counter by 1.
+	// Inc increments the counter by 1. Use Add to increment it by arbitrary
+	// non-negative values.
 	Inc()
 	// Add adds the given value to the counter. It panics if the value is <
 	// 0.

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

@@ -16,20 +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 = "__"
@@ -78,7 +73,7 @@ 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
 }
@@ -103,7 +98,7 @@ 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
 	}
@@ -200,6 +195,6 @@ func (d *Desc) String() string {
 }
 
 func checkLabelName(l string) bool {
-	return labelNameRE.MatchString(l) &&
+	return model.LabelName(l).IsValid() &&
 		!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
 //
@@ -59,7 +59,7 @@
 //    	// The Handler function provides a default handler to expose metrics
 //    	// via an HTTP server. "/metrics" is the usual endpoint for that.
 //    	http.Handle("/metrics", promhttp.Handler())
-//    	http.ListenAndServe(":8080", nil)
+//      log.Fatal(http.ListenAndServe(":8080", nil))
 //    }
 //
 //
@@ -69,7 +69,7 @@
 // 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 +95,8 @@
 // SummaryVec, HistogramVec, and UntypedVec are not.
 //
 // To create instances of Metrics and their vector versions, you need a suitable
-// …Opts struct, i.e. GaugeOpts, CounterOpts, SummaryOpts,
-// HistogramOpts, or UntypedOpts.
+// …Opts struct, i.e. GaugeOpts, CounterOpts, SummaryOpts, HistogramOpts, or
+// UntypedOpts.
 //
 // Custom Collectors and constant Metrics
 //
@@ -114,8 +114,8 @@
 // Metric instances “on the fly” using NewConstMetric, NewConstHistogram, and
 // NewConstSummary (and their respective Must… versions). That will happen in
 // the Collect method. The Describe method has to return separate Desc
-// instances, representative of the “throw-away” metrics to be created
-// later. NewDesc comes in handy to create those Desc instances.
+// instances, representative of the “throw-away” metrics to be created later.
+// NewDesc comes in handy to create those Desc instances.
 //
 // The Collector example illustrates the use case. You can also look at the
 // source code of the processCollector (mirroring process metrics), the
@@ -129,32 +129,32 @@
 // Advanced Uses of the Registry
 //
 // While MustRegister is the by far most common way of registering a Collector,
-// sometimes you might want to handle the errors the registration might
-// cause. As suggested by the name, MustRegister panics if an error occurs. With
-// the Register function, the error is returned and can be handled.
+// sometimes you might want to handle the errors the registration might cause.
+// As suggested by the name, MustRegister panics if an error occurs. With the
+// Register function, the error is returned and can be handled.
 //
 // An error is returned if the registered Collector is incompatible or
 // inconsistent with already registered metrics. The registry aims for
-// consistency of the collected metrics according to the Prometheus data
-// model. Inconsistencies are ideally detected at registration time, not at
-// collect time. The former will usually be detected at start-up time of a
-// program, while the latter will only happen at scrape time, possibly not even
-// on the first scrape if the inconsistency only becomes relevant later. That is
-// the main reason why a Collector and a Metric have to describe themselves to
-// the registry.
+// consistency of the collected metrics according to the Prometheus data model.
+// Inconsistencies are ideally detected at registration time, not at collect
+// time. The former will usually be detected at start-up time of a program,
+// while the latter will only happen at scrape time, possibly not even on the
+// first scrape if the inconsistency only becomes relevant later. That is the
+// main reason why a Collector and a Metric have to describe themselves to the
+// registry.
 //
 // So far, everything we did operated on the so-called default registry, as it
 // can be found in the global DefaultRegistry variable. With NewRegistry, you
 // can create a custom registry, or you can even implement the Registerer or
-// Gatherer interfaces yourself. The methods Register and Unregister work in
-// the same way on a custom registry as the global functions Register and
-// Unregister on the default registry.
+// Gatherer interfaces yourself. The methods Register and Unregister work in the
+// same way on a custom registry as the global functions Register and Unregister
+// on the default registry.
 //
-// There are a number of uses for custom registries: You can use registries
-// with special properties, see NewPedanticRegistry. You can avoid global state,
-// as it is imposed by the DefaultRegistry. You can use multiple registries at
-// the same time to expose different metrics in different ways. You can use
-// separate registries for testing purposes.
+// There are a number of uses for custom registries: You can use registries with
+// special properties, see NewPedanticRegistry. You can avoid global state, as
+// it is imposed by the DefaultRegistry. You can use multiple registries at the
+// same time to expose different metrics in different ways. You can use separate
+// registries for testing purposes.
 //
 // Also note that the DefaultRegistry comes registered with a Collector for Go
 // runtime metrics (via NewGoCollector) and a Collector for process metrics (via
@@ -166,16 +166,20 @@
 // 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
-// sub-package. (The top-level functions in the prometheus package are
-// deprecated.)
+// above. The tools to expose metrics via HTTP are in the promhttp sub-package.
+// (The top-level functions in the prometheus package are deprecated.)
 //
 // Pushing to the Pushgateway
 //
 // Function for pushing to the Pushgateway can be found in the push sub-package.
 //
+// Graphite Bridge
+//
+// Functions and examples to push metrics from a Gatherer to Graphite can be
+// found in the graphite sub-package.
+//
 // Other Means of Exposition
 //
-// More ways of exposing metrics can easily be added. Sending metrics to
-// Graphite would be an example that will soon be implemented.
+// More ways of exposing metrics can easily be added by following the approaches
+// of the existing implementations.
 package prometheus

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

@@ -27,16 +27,21 @@ 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
-	// negative, resulting in a decrease of the Gauge.)
+	// Add adds the given value to the Gauge. (The value can be negative,
+	// resulting in a decrease of the Gauge.)
 	Add(float64)
 	// Sub subtracts the given value from the Gauge. (The value can be
 	// negative, resulting in an increase of the Gauge.)
 	Sub(float64)
+
+	// SetToCurrentTime sets the Gauge to the current Unix time in seconds.
+	SetToCurrentTime()
 }
 
 // GaugeOpts is an alias for Opts. See there for doc comments.

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

@@ -8,7 +8,8 @@ import (
 )
 
 type goCollector struct {
-	goroutines Gauge
+	goroutinesDesc *Desc
+	threadsDesc    *Desc
 	gcDesc         *Desc
 
 	// metrics to describe and collect
@@ -19,11 +20,14 @@ type goCollector struct {
 // go process.
 func NewGoCollector() Collector {
 	return &goCollector{
-		goroutines: NewGauge(GaugeOpts{
-			Namespace: "go",
-			Name:      "goroutines",
-			Help:      "Number of goroutines that currently exist.",
-		}),
+		goroutinesDesc: NewDesc(
+			"go_goroutines",
+			"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.",
@@ -48,7 +52,7 @@ 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 +115,12 @@ func NewGoCollector() Collector {
 				valType: GaugeValue,
 			}, {
 				desc: NewDesc(
-					memstatNamespace("heap_released_bytes_total"),
-					"Total number of heap bytes released to OS.",
+					memstatNamespace("heap_released_bytes"),
+					"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 +217,14 @@ 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 +236,9 @@ 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
-
 	for _, i := range c.metrics {
 		ch <- i.desc
 	}
@@ -234,8 +246,9 @@ 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 <- c.goroutines
+	ch <- MustNewConstMetric(c.goroutinesDesc, GaugeValue, float64(runtime.NumGoroutine()))
+	n, _ := runtime.ThreadCreateProfile(nil)
+	ch <- MustNewConstMetric(c.threadsDesc, GaugeValue, float64(n))
 
 	var stats debug.GCStats
 	stats.PauseQuantiles = make([]time.Duration, 5)

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

@@ -62,7 +62,7 @@ func giveBuf(buf *bytes.Buffer) {
 //
 // Deprecated: Please note the issues described in the doc comment of
 // InstrumentHandler. You might want to consider using promhttp.Handler instead
-// (which is non instrumented).
+// (which is not instrumented).
 func Handler() http.Handler {
 	return InstrumentHandler("prometheus", UninstrumentedHandler())
 }
@@ -172,6 +172,9 @@ func nowSeries(t ...time.Time) nower {
 // httputil.ReverseProxy is a prominent example for a handler
 // performing such writes.
 //
+// - It has additional issues with HTTP/2, cf.
+// https://github.com/prometheus/client_golang/issues/272.
+//
 // Upcoming versions of this package will provide ways of instrumenting HTTP
 // handlers that are more flexible and have fewer issues. Please prefer direct
 // instrumentation in the meantime.
@@ -190,6 +193,7 @@ func InstrumentHandlerFunc(handlerName string, handlerFunc func(http.ResponseWri
 		SummaryOpts{
 			Subsystem:   "http",
 			ConstLabels: Labels{"handler": handlerName},
+			Objectives:  map[float64]float64{0.5: 0.05, 0.9: 0.01, 0.99: 0.001},
 		},
 		handlerFunc,
 	)
@@ -245,34 +249,52 @@ 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)
-
-	regReqCnt := MustRegisterOrGet(reqCnt).(*CounterVec)
-	regReqDur := MustRegisterOrGet(reqDur).(Summary)
-	regReqSz := MustRegisterOrGet(reqSz).(Summary)
-	regResSz := MustRegisterOrGet(resSz).(Summary)
+	if err := Register(resSz); err != nil {
+		if are, ok := err.(AlreadyRegisteredError); ok {
+			resSz = are.ExistingCollector.(Summary)
+		} else {
+			panic(err)
+		}
+	}
 
 	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		now := time.Now()
 
 		delegate := &responseWriterDelegator{ResponseWriter: w}
-		out := make(chan int)
-		urlLen := 0
-		if r.URL != nil {
-			urlLen = len(r.URL.String())
-		}
-		go computeApproximateRequestSize(r, out, urlLen)
+		out := computeApproximateRequestSize(r)
 
 		_, cn := w.(http.CloseNotifier)
 		_, fl := w.(http.Flusher)
@@ -290,14 +312,24 @@ func InstrumentHandlerFuncWithOpts(opts SummaryOpts, handlerFunc func(http.Respo
 
 		method := sanitizeMethod(r.Method)
 		code := sanitizeCode(delegate.status)
-		regReqCnt.WithLabelValues(method, code).Inc()
-		regReqDur.Observe(elapsed)
-		regResSz.Observe(float64(delegate.written))
-		regReqSz.Observe(float64(<-out))
+		reqCnt.WithLabelValues(method, code).Inc()
+		reqDur.Observe(elapsed)
+		resSz.Observe(float64(delegate.written))
+		reqSz.Observe(float64(<-out))
 	})
 }
 
-func computeApproximateRequestSize(r *http.Request, out chan int, s int) {
+func computeApproximateRequestSize(r *http.Request) <-chan int {
+	// Get URL length in current go routine for avoiding a race condition.
+	// HandlerFunc that runs in parallel may modify the URL.
+	s := 0
+	if r.URL != nil {
+		s += len(r.URL.String())
+	}
+
+	out := make(chan int, 1)
+
+	go func() {
 		s += len(r.Method)
 		s += len(r.Proto)
 		for name, values := range r.Header {
@@ -314,6 +346,10 @@ func computeApproximateRequestSize(r *http.Request, out chan int, s int) {
 			s += int(r.ContentLength)
 		}
 		out <- s
+		close(out)
+	}()
+
+	return out
 }
 
 type responseWriterDelegator struct {

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
-	openFDs, maxFDs Gauge
-	vsize, rss      Gauge
-	startTime       Gauge
+	cpuTotal        *Desc
+	openFDs, maxFDs *Desc
+	vsize, rss      *Desc
+	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{
-			Namespace: namespace,
-			Name:      "process_cpu_seconds_total",
-			Help:      "Total user and system CPU time spent in seconds.",
-		}),
-		openFDs: NewGauge(GaugeOpts{
-			Namespace: namespace,
-			Name:      "process_open_fds",
-			Help:      "Number of open file descriptors.",
-		}),
-		maxFDs: NewGauge(GaugeOpts{
-			Namespace: namespace,
-			Name:      "process_max_fds",
-			Help:      "Maximum number of open file descriptors.",
-		}),
-		vsize: NewGauge(GaugeOpts{
-			Namespace: namespace,
-			Name:      "process_virtual_memory_bytes",
-			Help:      "Virtual memory size in bytes.",
-		}),
-		rss: NewGauge(GaugeOpts{
-			Namespace: namespace,
-			Name:      "process_resident_memory_bytes",
-			Help:      "Resident memory size in bytes.",
-		}),
-		startTime: NewGauge(GaugeOpts{
-			Namespace: namespace,
-			Name:      "process_start_time_seconds",
-			Help:      "Start time of the process since unix epoch in seconds.",
-		}),
+		cpuTotal: NewDesc(
+			ns+"process_cpu_seconds_total",
+			"Total user and system CPU time spent in seconds.",
+			nil, nil,
+		),
+		openFDs: NewDesc(
+			ns+"process_open_fds",
+			"Number of open file descriptors.",
+			nil, nil,
+		),
+		maxFDs: NewDesc(
+			ns+"process_max_fds",
+			"Maximum number of open file descriptors.",
+			nil, nil,
+		),
+		vsize: NewDesc(
+			ns+"process_virtual_memory_bytes",
+			"Virtual memory size in bytes.",
+			nil, nil,
+		),
+		rss: NewDesc(
+			ns+"process_resident_memory_bytes",
+			"Resident memory size in bytes.",
+			nil, nil,
+		),
+		startTime: NewDesc(
+			ns+"process_start_time_seconds",
+			"Start time of the process since unix epoch in seconds.",
+			nil, nil,
+		),
 	}
 
 	// 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.openFDs.Desc()
-	ch <- c.maxFDs.Desc()
-	ch <- c.vsize.Desc()
-	ch <- c.rss.Desc()
-	ch <- c.startTime.Desc()
+	ch <- c.cpuTotal
+	ch <- c.openFDs
+	ch <- c.maxFDs
+	ch <- c.vsize
+	ch <- c.rss
+	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 <- c.cpuTotal
-		c.vsize.Set(float64(stat.VirtualMemory()))
-		ch <- c.vsize
-		c.rss.Set(float64(stat.ResidentMemory()))
-		ch <- c.rss
-
+		ch <- MustNewConstMetric(c.cpuTotal, CounterValue, stat.CPUTime())
+		ch <- MustNewConstMetric(c.vsize, GaugeValue, float64(stat.VirtualMemory()))
+		ch <- MustNewConstMetric(c.rss, GaugeValue, float64(stat.ResidentMemory()))
 		if startTime, err := stat.StartTime(); err == nil {
-			c.startTime.Set(startTime)
-			ch <- c.startTime
+			ch <- MustNewConstMetric(c.startTime, GaugeValue, startTime)
 		}
 	}
 
 	if fds, err := p.FileDescriptorsLen(); err == nil {
-		c.openFDs.Set(float64(fds))
-		ch <- c.openFDs
+		ch <- MustNewConstMetric(c.openFDs, GaugeValue, float64(fds))
 	}
 
 	if limits, err := p.NewLimits(); err == nil {
-		c.maxFDs.Set(float64(limits.OpenFiles))
-		ch <- c.maxFDs
+		ch <- MustNewConstMetric(c.maxFDs, GaugeValue, float64(limits.OpenFiles))
 	}
 }

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

@@ -152,38 +152,6 @@ 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 +169,6 @@ 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
@@ -294,7 +243,7 @@ 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?
@@ -447,7 +396,7 @@ func (r *Registry) Gather() ([]*dto.MetricFamily, error) {
 
 	// Drain metricChan in case of premature return.
 	defer func() {
-		for _ = range metricChan {
+		for range metricChan {
 		}
 	}()
 
@@ -683,7 +632,7 @@ 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 {

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

@@ -54,6 +54,9 @@ 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}
 
@@ -113,9 +116,15 @@ type SummaryOpts struct {
 	ConstLabels Labels
 
 	// Objectives defines the quantile rank estimates with their respective
-	// absolute error. If Objectives[q] = e, then the value reported
-	// for q will be the φ-quantile value for some φ between q-e and q+e.
-	// The default value is DefObjectives.
+	// absolute error. If Objectives[q] = e, then the value reported for q
+	// will be the φ-quantile value for some φ between q-e and q+e.  The
+	// default value is DefObjectives. It is used if Objectives is left at
+	// its zero value (i.e. nil). To create a Summary without Objectives,
+	// set it to an empty map (i.e. map[float64]float64{}).
+	//
+	// Deprecated: Note that the current value of DefObjectives is
+	// deprecated. It will be replaced by an empty map in v0.10 of the
+	// library. Please explicitly set Objectives to the desired value.
 	Objectives map[float64]float64
 
 	// MaxAge defines the duration for which an observation stays relevant
@@ -183,7 +192,7 @@ func newSummary(desc *Desc, opts SummaryOpts, labelValues ...string) Summary {
 		}
 	}
 
-	if len(opts.Objectives) == 0 {
+	if opts.Objectives == nil {
 		opts.Objectives = DefObjectives
 	}
 

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

@@ -0,0 +1,74 @@
+// 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"
+
+// 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)
+}
+
+// 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.
+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

@@ -20,6 +20,11 @@ package prometheus
 // no type information is implied.
 //
 // To create Untyped instances, use NewUntyped.
+//
+// Deprecated: The Untyped type is deprecated because it doesn't make sense in
+// direct instrumentation. If you need to mirror an external metric of unknown
+// type (usually while writing exporters), Use MustNewConstMetric to create an
+// untyped metric instance on the fly.
 type Untyped interface {
 	Metric
 	Collector

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

@@ -19,6 +19,7 @@ import (
 	"math"
 	"sort"
 	"sync/atomic"
+	"time"
 
 	dto "github.com/prometheus/client_model/go"
 
@@ -43,7 +44,7 @@ var errInconsistentCardinality = errors.New("inconsistent label cardinality")
 // 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
+	// 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
@@ -80,6 +81,10 @@ func (v *value) Set(val float64) {
 	atomic.StoreUint64(&v.valBits, math.Float64bits(val))
 }
 
+func (v *value) SetToCurrentTime() {
+	v.Set(float64(time.Now().UnixNano()) / 1e9)
+}
+
 func (v *value) Inc() {
 	v.Add(1)
 }

vendor/vendor.json

@@ -519,10 +519,10 @@
 			"revisionTime": "2016-06-15T09:26:46Z"
 		},
 		{
-			"checksumSHA1": "KkB+77Ziom7N6RzSbyUwYGrmDeU=",
+			"checksumSHA1": "d2irkxoHgazkTuLIvJGiYwagl8o=",
 			"path": "github.com/prometheus/client_golang/prometheus",
-			"revision": "c5b7fccd204277076155f10851dad72b76a49317",
-			"revisionTime": "2016-08-17T15:48:24Z"
+			"revision": "08fd2e12372a66e68e30523c7642e0cbc3e4fbde",
+			"revisionTime": "2017-04-01T10:34:46Z"
 		},
 		{
 			"checksumSHA1": "DvwvOlPNAgRntBzt3b3OSRMS2N4=",
@@ -531,10 +531,10 @@
 			"revisionTime": "2015-02-12T10:17:44Z"
 		},
 		{
-			"checksumSHA1": "jG8qYuDUuaZeflt4JxBBdyQBsXw=",
+			"checksumSHA1": "Wtpzndm/+bdwwNU5PCTfb4oUhc8=",
 			"path": "github.com/prometheus/common/expfmt",
-			"revision": "dd2f054febf4a6c00f2343686efb775948a8bff4",
-			"revisionTime": "2017-01-08T23:12:12Z"
+			"revision": "49fee292b27bfff7f354ee0f64e1bc4850462edf",
+			"revisionTime": "2017-02-20T10:38:46Z"
 		},
 		{
 			"checksumSHA1": "GWlM3d2vPYyNATtTFgftS10/A9w=",
@@ -549,10 +549,10 @@
 			"revisionTime": "2017-01-08T23:12:12Z"
 		},
 		{
-			"checksumSHA1": "vopCLXHzYm+3l5fPKOf4/fQwrCM=",
+			"checksumSHA1": "0LL9u9tfv1KPBjNEiMDP6q7lpog=",
 			"path": "github.com/prometheus/common/model",
-			"revision": "3007b6072c17c8d985734e6e19b1dea9174e13d3",
-			"revisionTime": "2017-02-19T00:35:58+01:00"
+			"revision": "49fee292b27bfff7f354ee0f64e1bc4850462edf",
+			"revisionTime": "2017-02-20T10:38:46Z"
 		},
 		{
 			"checksumSHA1": "ZbbESWBHHcPUJ/A5yrzKhTHuPc8=",