Update vendoring of client_golang and friends

Signed-off-by: beorn7 <beorn@soundcloud.com>

vendor/github.com/prometheus/client_golang/api/client.go

@@ -30,10 +30,10 @@ import (
 // DefaultRoundTripper is used if no RoundTripper is set in Config.
 var DefaultRoundTripper http.RoundTripper = &http.Transport{
 	Proxy: http.ProxyFromEnvironment,
-	Dial: (&net.Dialer{
+	DialContext: (&net.Dialer{
 		Timeout:   30 * time.Second,
 		KeepAlive: 30 * time.Second,
-	}).Dial,
+	}).DialContext,
 	TLSHandshakeTimeout: 10 * time.Second,
 }
 

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

@@ -29,27 +29,71 @@ type Collector interface {
 	// collected by this Collector to the provided channel and returns once
 	// the last descriptor has been sent. The sent descriptors fulfill the
 	// consistency and uniqueness requirements described in the Desc
-	// documentation. (It is valid if one and the same Collector sends
+	// documentation.
-	// duplicate descriptors. Those duplicates are simply ignored. However,
+	//
-	// two different Collectors must not send duplicate descriptors.) This
+	// It is valid if one and the same Collector sends duplicate
-	// method idempotently sends the same descriptors throughout the
+	// descriptors. Those duplicates are simply ignored. However, two
-	// lifetime of the Collector. If a Collector encounters an error while
+	// different Collectors must not send duplicate descriptors.
-	// executing this method, it must send an invalid descriptor (created
+	//
-	// with NewInvalidDesc) to signal the error to the registry.
+	// Sending no descriptor at all marks the Collector as “unchecked”,
+	// i.e. no checks will be performed at registration time, and the
+	// Collector may yield any Metric it sees fit in its Collect method.
+	//
+	// This method idempotently sends the same descriptors throughout the
+	// lifetime of the Collector.
+	//
+	// If a Collector encounters an error while executing this method, it
+	// must send an invalid descriptor (created with NewInvalidDesc) to
+	// signal the error to the registry.
 	Describe(chan<- *Desc)
 	// Collect is called by the Prometheus registry when collecting
 	// metrics. The implementation sends each collected metric via the
 	// provided channel and returns once the last metric has been sent. The
-	// descriptor of each sent metric is one of those returned by
+	// descriptor of each sent metric is one of those returned by Describe
-	// Describe. Returned metrics that share the same descriptor must differ
+	// (unless the Collector is unchecked, see above). Returned metrics that
-	// in their variable label values. This method may be called
+	// share the same descriptor must differ in their variable label
-	// concurrently and must therefore be implemented in a concurrency safe
+	// values.
-	// way. Blocking occurs at the expense of total performance of rendering
+	//
-	// all registered metrics. Ideally, Collector implementations support
+	// This method may be called concurrently and must therefore be
-	// concurrent readers.
+	// implemented in a concurrency safe way. Blocking occurs at the expense
+	// of total performance of rendering all registered metrics. Ideally,
+	// Collector implementations support concurrent readers.
 	Collect(chan<- Metric)
 }
 
+// DescribeByCollect is a helper to implement the Describe method of a custom
+// Collector. It collects the metrics from the provided Collector and sends
+// their descriptors to the provided channel.
+//
+// If a Collector collects the same metrics throughout its lifetime, its
+// Describe method can simply be implemented as:
+//
+//   func (c customCollector) Describe(ch chan<- *Desc) {
+//   	DescribeByCollect(c, ch)
+//   }
+//
+// However, this will not work if the metrics collected change dynamically over
+// the lifetime of the Collector in a way that their combined set of descriptors
+// changes as well. The shortcut implementation will then violate the contract
+// of the Describe method. If a Collector sometimes collects no metrics at all
+// (for example vectors like CounterVec, GaugeVec, etc., which only collect
+// metrics after a metric with a fully specified label set has been accessed),
+// it might even get registered as an unchecked Collecter (cf. the Register
+// method of the Registerer interface). Hence, only use this shortcut
+// implementation of Describe if you are certain to fulfill the contract.
+//
+// The Collector example demonstrates a use of DescribeByCollect.
+func DescribeByCollect(c Collector, descs chan<- *Desc) {
+	metrics := make(chan Metric)
+	go func() {
+		c.Collect(metrics)
+		close(metrics)
+	}()
+	for m := range metrics {
+		descs <- m.Desc()
+	}
+}
+
 // selfCollector implements Collector for a single Metric so that the Metric
 // collects itself. Add it as an anonymous field to a struct that implements
 // Metric, and call init with the Metric itself as an argument.

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

@@ -67,7 +67,7 @@ type Desc struct {
 
 // NewDesc allocates and initializes a new Desc. Errors are recorded in the Desc
 // and will be reported on registration time. variableLabels and constLabels can
-// be nil if no such labels should be set. fqName and help must not be empty.
+// be nil if no such labels should be set. fqName must not be empty.
 //
 // variableLabels only contain the label names. Their label values are variable
 // and therefore not part of the Desc. (They are managed within the Metric.)
@@ -80,10 +80,6 @@ func NewDesc(fqName, help string, variableLabels []string, constLabels Labels) *
 		help:           help,
 		variableLabels: variableLabels,
 	}
-	if help == "" {
-		d.err = errors.New("empty help string")
-		return d
-	}
 	if !model.IsValidMetricName(model.LabelValue(fqName)) {
 		d.err = fmt.Errorf("%q is not a valid metric name", fqName)
 		return d
@@ -156,7 +152,7 @@ func NewDesc(fqName, help string, variableLabels []string, constLabels Labels) *
 			Value: proto.String(v),
 		})
 	}
-	sort.Sort(LabelPairSorter(d.constLabelPairs))
+	sort.Sort(labelPairSorter(d.constLabelPairs))
 	return d
 }
 

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

@@ -121,7 +121,17 @@
 // 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.
+// NewDesc comes in handy to create those Desc instances. Alternatively, you
+// could return no Desc at all, which will marke the Collector “unchecked”.  No
+// checks are porformed at registration time, but metric consistency will still
+// be ensured at scrape time, i.e. any inconsistencies will lead to scrape
+// errors. Thus, with unchecked Collectors, the responsibility to not collect
+// metrics that lead to inconsistencies in the total scrape result lies with the
+// implementer of the Collector. While this is not a desirable state, it is
+// sometimes necessary. The typical use case is a situatios where the exact
+// metrics to be returned by a Collector cannot be predicted at registration
+// time, but the implementer has sufficient knowledge of the whole system to
+// guarantee metric consistency.
 //
 // The Collector example illustrates the use case. You can also look at the
 // source code of the processCollector (mirroring process metrics), the

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

@@ -1,3 +1,16 @@
+// 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 prometheus
 
 // Inline and byte-free variant of hash/fnv's fnv64a.

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

@@ -1,3 +1,16 @@
+// 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 prometheus
 
 import (

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

@@ -16,7 +16,9 @@ package prometheus
 import (
 	"fmt"
 	"math"
+	"runtime"
 	"sort"
+	"sync"
 	"sync/atomic"
 
 	"github.com/golang/protobuf/proto"
@@ -108,8 +110,9 @@ func ExponentialBuckets(start, factor float64, count int) []float64 {
 }
 
 // HistogramOpts bundles the options for creating a Histogram metric. It is
-// mandatory to set Name and Help to a non-empty string. All other fields are
+// mandatory to set Name to a non-empty string. All other fields are optional
-// optional and can safely be left at their zero value.
+// and can safely be left at their zero value, although it is strongly
+// encouraged to set a Help string.
 type HistogramOpts struct {
 	// Namespace, Subsystem, and Name are components of the fully-qualified
 	// name of the Histogram (created by joining these components with
@@ -120,7 +123,7 @@ type HistogramOpts struct {
 	Subsystem string
 	Name      string
 
-	// Help provides information about this Histogram. Mandatory!
+	// Help provides information about this Histogram.
 	//
 	// Metrics with the same fully-qualified name must have the same Help
 	// string.
@@ -200,28 +203,49 @@ func newHistogram(desc *Desc, opts HistogramOpts, labelValues ...string) Histogr
 			}
 		}
 	}
-	// Finally we know the final length of h.upperBounds and can make counts.
+	// Finally we know the final length of h.upperBounds and can make counts
-	h.counts = make([]uint64, len(h.upperBounds))
+	// for both states:
+	h.counts[0].buckets = make([]uint64, len(h.upperBounds))
+	h.counts[1].buckets = make([]uint64, len(h.upperBounds))
 
 	h.init(h) // Init self-collection.
 	return h
 }
 
-type histogram struct {
+type histogramCounts struct {
 	// sumBits contains the bits of the float64 representing the sum of all
 	// observations. sumBits and count have to go first in the struct to
 	// guarantee alignment for atomic operations.
 	// http://golang.org/pkg/sync/atomic/#pkg-note-BUG
 	sumBits uint64
 	count   uint64
+	buckets []uint64
+}
 
+type histogram struct {
 	selfCollector
-	// Note that there is no mutex required.
+	desc     *Desc
-
+	writeMtx sync.Mutex // Only used in the Write method.
-	desc *Desc
 
 	upperBounds []float64
-	counts      []uint64
+
+	// Two counts, one is "hot" for lock-free observations, the other is
+	// "cold" for writing out a dto.Metric.
+	counts [2]histogramCounts
+
+	hotIdx int // Index of currently-hot counts. Only used within Write.
+
+	// This is a complicated one. For lock-free yet atomic observations, we
+	// need to save the total count of observations again, combined with the
+	// index of the currently-hot counts struct, so that we can perform the
+	// operation on both values atomically. The least significant bit
+	// defines the hot counts struct. The remaining 63 bits represent the
+	// total count of observations. This happens under the assumption that
+	// the 63bit count will never overflow. Rationale: An observations takes
+	// about 30ns. Let's assume it could happen in 10ns. Overflowing the
+	// counter will then take at least (2^63)*10ns, which is about 3000
+	// years.
+	countAndHotIdx uint64
 
 	labelPairs []*dto.LabelPair
 }
@@ -241,36 +265,113 @@ func (h *histogram) Observe(v float64) {
 	// 100 buckets: 78.1 ns/op linear - binary 54.9 ns/op
 	// 300 buckets: 154 ns/op linear - binary 61.6 ns/op
 	i := sort.SearchFloat64s(h.upperBounds, v)
-	if i < len(h.counts) {
+
-		atomic.AddUint64(&h.counts[i], 1)
+	// We increment h.countAndHotIdx by 2 so that the counter in the upper
+	// 63 bits gets incremented by 1. At the same time, we get the new value
+	// back, which we can use to find the currently-hot counts.
+	n := atomic.AddUint64(&h.countAndHotIdx, 2)
+	hotCounts := &h.counts[n%2]
+
+	if i < len(h.upperBounds) {
+		atomic.AddUint64(&hotCounts.buckets[i], 1)
 	}
-	atomic.AddUint64(&h.count, 1)
 	for {
-		oldBits := atomic.LoadUint64(&h.sumBits)
+		oldBits := atomic.LoadUint64(&hotCounts.sumBits)
 		newBits := math.Float64bits(math.Float64frombits(oldBits) + v)
-		if atomic.CompareAndSwapUint64(&h.sumBits, oldBits, newBits) {
+		if atomic.CompareAndSwapUint64(&hotCounts.sumBits, oldBits, newBits) {
 			break
 		}
 	}
+	// Increment count last as we take it as a signal that the observation
+	// is complete.
+	atomic.AddUint64(&hotCounts.count, 1)
 }
 
 func (h *histogram) Write(out *dto.Metric) error {
-	his := &dto.Histogram{}
+	var (
-	buckets := make([]*dto.Bucket, len(h.upperBounds))
+		his                   = &dto.Histogram{}
+		buckets               = make([]*dto.Bucket, len(h.upperBounds))
+		hotCounts, coldCounts *histogramCounts
+		count                 uint64
+	)
 
-	his.SampleSum = proto.Float64(math.Float64frombits(atomic.LoadUint64(&h.sumBits)))
+	// For simplicity, we mutex the rest of this method. It is not in the
-	his.SampleCount = proto.Uint64(atomic.LoadUint64(&h.count))
+	// hot path, i.e.  Observe is called much more often than Write. The
-	var count uint64
+	// complication of making Write lock-free isn't worth it.
+	h.writeMtx.Lock()
+	defer h.writeMtx.Unlock()
+
+	// This is a bit arcane, which is why the following spells out this if
+	// clause in English:
+	//
+	// If the currently-hot counts struct is #0, we atomically increment
+	// h.countAndHotIdx by 1 so that from now on Observe will use the counts
+	// struct #1. Furthermore, the atomic increment gives us the new value,
+	// which, in its most significant 63 bits, tells us the count of
+	// observations done so far up to and including currently ongoing
+	// observations still using the counts struct just changed from hot to
+	// cold. To have a normal uint64 for the count, we bitshift by 1 and
+	// save the result in count. We also set h.hotIdx to 1 for the next
+	// Write call, and we will refer to counts #1 as hotCounts and to counts
+	// #0 as coldCounts.
+	//
+	// If the currently-hot counts struct is #1, we do the corresponding
+	// things the other way round. We have to _decrement_ h.countAndHotIdx
+	// (which is a bit arcane in itself, as we have to express -1 with an
+	// unsigned int...).
+	if h.hotIdx == 0 {
+		count = atomic.AddUint64(&h.countAndHotIdx, 1) >> 1
+		h.hotIdx = 1
+		hotCounts = &h.counts[1]
+		coldCounts = &h.counts[0]
+	} else {
+		count = atomic.AddUint64(&h.countAndHotIdx, ^uint64(0)) >> 1 // Decrement.
+		h.hotIdx = 0
+		hotCounts = &h.counts[0]
+		coldCounts = &h.counts[1]
+	}
+
+	// Now we have to wait for the now-declared-cold counts to actually cool
+	// down, i.e. wait for all observations still using it to finish. That's
+	// the case once the count in the cold counts struct is the same as the
+	// one atomically retrieved from the upper 63bits of h.countAndHotIdx.
+	for {
+		if count == atomic.LoadUint64(&coldCounts.count) {
+			break
+		}
+		runtime.Gosched() // Let observations get work done.
+	}
+
+	his.SampleCount = proto.Uint64(count)
+	his.SampleSum = proto.Float64(math.Float64frombits(atomic.LoadUint64(&coldCounts.sumBits)))
+	var cumCount uint64
 	for i, upperBound := range h.upperBounds {
-		count += atomic.LoadUint64(&h.counts[i])
+		cumCount += atomic.LoadUint64(&coldCounts.buckets[i])
 		buckets[i] = &dto.Bucket{
-			CumulativeCount: proto.Uint64(count),
+			CumulativeCount: proto.Uint64(cumCount),
 			UpperBound:      proto.Float64(upperBound),
 		}
 	}
+
 	his.Bucket = buckets
 	out.Histogram = his
 	out.Label = h.labelPairs
+
+	// Finally add all the cold counts to the new hot counts and reset the cold counts.
+	atomic.AddUint64(&hotCounts.count, count)
+	atomic.StoreUint64(&coldCounts.count, 0)
+	for {
+		oldBits := atomic.LoadUint64(&hotCounts.sumBits)
+		newBits := math.Float64bits(math.Float64frombits(oldBits) + his.GetSampleSum())
+		if atomic.CompareAndSwapUint64(&hotCounts.sumBits, oldBits, newBits) {
+			atomic.StoreUint64(&coldCounts.sumBits, 0)
+			break
+		}
+	}
+	for i := range h.upperBounds {
+		atomic.AddUint64(&hotCounts.buckets[i], atomic.LoadUint64(&coldCounts.buckets[i]))
+		atomic.StoreUint64(&coldCounts.buckets[i], 0)
+	}
 	return nil
 }
 
@@ -454,7 +555,7 @@ func (h *constHistogram) Write(out *dto.Metric) error {
 // bucket.
 //
 // NewConstHistogram returns an error if the length of labelValues is not
-// consistent with the variable labels in Desc.
+// consistent with the variable labels in Desc or if Desc is invalid.
 func NewConstHistogram(
 	desc *Desc,
 	count uint64,
@@ -462,6 +563,9 @@ func NewConstHistogram(
 	buckets map[float64]uint64,
 	labelValues ...string,
 ) (Metric, error) {
+	if desc.err != nil {
+		return nil, desc.err
+	}
 	if err := validateLabelValues(labelValues, len(desc.variableLabels)); err != nil {
 		return nil, err
 	}

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

@@ -61,15 +61,15 @@ func giveBuf(buf *bytes.Buffer) {
 // name).
 //
 // Deprecated: Please note the issues described in the doc comment of
-// InstrumentHandler. You might want to consider using
+// InstrumentHandler. You might want to consider using promhttp.Handler instead.
-// promhttp.InstrumentedHandler instead.
 func Handler() http.Handler {
 	return InstrumentHandler("prometheus", UninstrumentedHandler())
 }
 
 // UninstrumentedHandler returns an HTTP handler for the DefaultGatherer.
 //
-// Deprecated: Use promhttp.Handler instead. See there for further documentation.
+// Deprecated: Use promhttp.HandlerFor(DefaultGatherer, promhttp.HandlerOpts{})
+// instead. See there for further documentation.
 func UninstrumentedHandler() http.Handler {
 	return http.HandlerFunc(func(w http.ResponseWriter, req *http.Request) {
 		mfs, err := DefaultGatherer.Gather()
@@ -149,21 +149,14 @@ var now nower = nowFunc(func() time.Time {
 // (label name "method") and HTTP status code (label name "code").
 //
 // Deprecated: InstrumentHandler has several issues. Use the tooling provided in
-// package promhttp instead. The issues are the following:
+// package promhttp instead. The issues are the following: (1) It uses Summaries
-//
+// rather than Histograms. Summaries are not useful if aggregation across
-// - It uses Summaries rather than Histograms. Summaries are not useful if
+// multiple instances is required. (2) It uses microseconds as unit, which is
-// aggregation across multiple instances is required.
+// deprecated and should be replaced by seconds. (3) The size of the request is
-//
+// calculated in a separate goroutine. Since this calculator requires access to
-// - It uses microseconds as unit, which is deprecated and should be replaced by
+// the request header, it creates a race with any writes to the header performed
-// seconds.
+// during request handling.  httputil.ReverseProxy is a prominent example for a
-//
+// handler performing such writes. (4) It has additional issues with HTTP/2, cf.
-// - The size of the request is calculated in a separate goroutine. Since this
-// calculator requires access to the request header, it creates a race with
-// any writes to the header performed during request handling.
-// 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.
 func InstrumentHandler(handlerName string, handler http.Handler) http.HandlerFunc {
 	return InstrumentHandlerFunc(handlerName, handler.ServeHTTP)
@@ -307,7 +300,7 @@ func InstrumentHandlerFuncWithOpts(opts SummaryOpts, handlerFunc func(http.Respo
 }
 
 func computeApproximateRequestSize(r *http.Request) <-chan int {
-	// Get URL length in current go routine for avoiding a race condition.
+	// Get URL length in current goroutine for avoiding a race condition.
 	// HandlerFunc that runs in parallel may modify the URL.
 	s := 0
 	if r.URL != nil {

vendor/github.com/prometheus/client_golang/prometheus/internal/metric.go

@@ -0,0 +1,85 @@
+// 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 internal
+
+import (
+	"sort"
+
+	dto "github.com/prometheus/client_model/go"
+)
+
+// metricSorter is a sortable slice of *dto.Metric.
+type metricSorter []*dto.Metric
+
+func (s metricSorter) Len() int {
+	return len(s)
+}
+
+func (s metricSorter) Swap(i, j int) {
+	s[i], s[j] = s[j], s[i]
+}
+
+func (s metricSorter) Less(i, j int) bool {
+	if len(s[i].Label) != len(s[j].Label) {
+		// This should not happen. The metrics are
+		// inconsistent. However, we have to deal with the fact, as
+		// people might use custom collectors or metric family injection
+		// to create inconsistent metrics. So let's simply compare the
+		// number of labels in this case. That will still yield
+		// reproducible sorting.
+		return len(s[i].Label) < len(s[j].Label)
+	}
+	for n, lp := range s[i].Label {
+		vi := lp.GetValue()
+		vj := s[j].Label[n].GetValue()
+		if vi != vj {
+			return vi < vj
+		}
+	}
+
+	// We should never arrive here. Multiple metrics with the same
+	// label set in the same scrape will lead to undefined ingestion
+	// behavior. However, as above, we have to provide stable sorting
+	// here, even for inconsistent metrics. So sort equal metrics
+	// by their timestamp, with missing timestamps (implying "now")
+	// coming last.
+	if s[i].TimestampMs == nil {
+		return false
+	}
+	if s[j].TimestampMs == nil {
+		return true
+	}
+	return s[i].GetTimestampMs() < s[j].GetTimestampMs()
+}
+
+// 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 {
+	for _, mf := range metricFamiliesByName {
+		sort.Sort(metricSorter(mf.Metric))
+	}
+	names := make([]string, 0, len(metricFamiliesByName))
+	for name, mf := range metricFamiliesByName {
+		if len(mf.Metric) > 0 {
+			names = append(names, name)
+		}
+	}
+	sort.Strings(names)
+	result := make([]*dto.MetricFamily, 0, len(names))
+	for _, name := range names {
+		result = append(result, metricFamiliesByName[name])
+	}
+	return result
+}

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

@@ -1,3 +1,16 @@
+// 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 prometheus
 
 import (

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

@@ -15,6 +15,9 @@ package prometheus
 
 import (
 	"strings"
+	"time"
+
+	"github.com/golang/protobuf/proto"
 
 	dto "github.com/prometheus/client_model/go"
 )
@@ -43,9 +46,8 @@ type Metric interface {
 	// While populating dto.Metric, it is the responsibility of the
 	// implementation to ensure validity of the Metric protobuf (like valid
 	// UTF-8 strings or syntactically valid metric and label names). It is
-	// recommended to sort labels lexicographically. (Implementers may find
+	// recommended to sort labels lexicographically. Callers of Write should
-	// LabelPairSorter useful for that.) Callers of Write should still make
+	// still make sure of sorting if they depend on it.
-	// sure of sorting if they depend on it.
 	Write(*dto.Metric) error
 	// TODO(beorn7): The original rationale of passing in a pre-allocated
 	// dto.Metric protobuf to save allocations has disappeared. The
@@ -57,8 +59,9 @@ type Metric interface {
 // implementation XXX has its own XXXOpts type, but in most cases, it is just be
 // an alias of this type (which might change when the requirement arises.)
 //
-// It is mandatory to set Name and Help to a non-empty string. All other fields
+// It is mandatory to set Name to a non-empty string. All other fields are
-// are optional and can safely be left at their zero value.
+// optional and can safely be left at their zero value, although it is strongly
+// encouraged to set a Help string.
 type Opts struct {
 	// Namespace, Subsystem, and Name are components of the fully-qualified
 	// name of the Metric (created by joining these components with
@@ -69,7 +72,7 @@ type Opts struct {
 	Subsystem string
 	Name      string
 
-	// Help provides information about this metric. Mandatory!
+	// Help provides information about this metric.
 	//
 	// Metrics with the same fully-qualified name must have the same Help
 	// string.
@@ -110,20 +113,19 @@ func BuildFQName(namespace, subsystem, name string) string {
 	return name
 }
 
-// LabelPairSorter implements sort.Interface. It is used to sort a slice of
+// labelPairSorter implements sort.Interface. It is used to sort a slice of
-// dto.LabelPair pointers. This is useful for implementing the Write method of
+// dto.LabelPair pointers.
-// custom metrics.
+type labelPairSorter []*dto.LabelPair
-type LabelPairSorter []*dto.LabelPair
 
-func (s LabelPairSorter) Len() int {
+func (s labelPairSorter) Len() int {
 	return len(s)
 }
 
-func (s LabelPairSorter) Swap(i, j int) {
+func (s labelPairSorter) Swap(i, j int) {
 	s[i], s[j] = s[j], s[i]
 }
 
-func (s LabelPairSorter) Less(i, j int) bool {
+func (s labelPairSorter) Less(i, j int) bool {
 	return s[i].GetName() < s[j].GetName()
 }
 
@@ -142,3 +144,31 @@ func NewInvalidMetric(desc *Desc, err error) Metric {
 func (m *invalidMetric) Desc() *Desc { return m.desc }
 
 func (m *invalidMetric) Write(*dto.Metric) error { return m.err }
+
+type timestampedMetric struct {
+	Metric
+	t time.Time
+}
+
+func (m timestampedMetric) Write(pb *dto.Metric) error {
+	e := m.Metric.Write(pb)
+	pb.TimestampMs = proto.Int64(m.t.Unix()*1000 + int64(m.t.Nanosecond()/1000000))
+	return e
+}
+
+// NewMetricWithTimestamp returns a new Metric wrapping the provided Metric in a
+// way that it has an explicit timestamp set to the provided Time. This is only
+// useful in rare cases as the timestamp of a Prometheus metric should usually
+// be set by the Prometheus server during scraping. Exceptions include mirroring
+// metrics with given timestamps from other metric
+// sources.
+//
+// NewMetricWithTimestamp works best with MustNewConstMetric,
+// MustNewConstHistogram, and MustNewConstSummary, see example.
+//
+// Currently, the exposition formats used by Prometheus are limited to
+// millisecond resolution. Thus, the provided time will be rounded down to the
+// next full millisecond value.
+func NewMetricWithTimestamp(t time.Time, m Metric) Metric {
+	return timestampedMetric{Metric: m, t: t}
+}

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

@@ -13,45 +13,74 @@
 
 package prometheus
 
-import "github.com/prometheus/procfs"
+import (
+	"errors"
+	"os"
+
+	"github.com/prometheus/procfs"
+)
 
 type processCollector struct {
 	collectFn       func(chan<- Metric)
 	pidFn           func() (int, error)
+	reportErrors    bool
 	cpuTotal        *Desc
 	openFDs, maxFDs *Desc
-	vsize, rss      *Desc
+	vsize, maxVsize *Desc
+	rss             *Desc
 	startTime       *Desc
 }
 
+// ProcessCollectorOpts defines the behavior of a process metrics collector
+// created with NewProcessCollector.
+type ProcessCollectorOpts struct {
+	// PidFn returns the PID of the process the collector collects metrics
+	// for. It is called upon each collection. By default, the PID of the
+	// current process is used, as determined on construction time by
+	// calling os.Getpid().
+	PidFn func() (int, error)
+	// If non-empty, each of the collected metrics is prefixed by the
+	// provided string and an underscore ("_").
+	Namespace string
+	// If true, any error encountered during collection is reported as an
+	// invalid metric (see NewInvalidMetric). Otherwise, errors are ignored
+	// and the collected metrics will be incomplete. (Possibly, no metrics
+	// will be collected at all.) While that's usually not desired, it is
+	// appropriate for the common "mix-in" of process metrics, where process
+	// metrics are nice to have, but failing to collect them should not
+	// disrupt the collection of the remaining metrics.
+	ReportErrors bool
+}
+
 // NewProcessCollector returns a collector which exports the current state of
 // process metrics including CPU, memory and file descriptor usage as well as
-// the process start time for the given process ID under the given namespace.
+// the process start time. The detailed behavior is defined by the provided
+// ProcessCollectorOpts. The zero value of ProcessCollectorOpts creates a
+// collector for the current process with an empty namespace string and no error
+// reporting.
 //
 // Currently, the collector depends on a Linux-style proc filesystem and
 // therefore only exports metrics for Linux.
-func NewProcessCollector(pid int, namespace string) Collector {
+//
-	return NewProcessCollectorPIDFn(
+// Note: An older version of this function had the following signature:
-		func() (int, error) { return pid, nil },
+//
-		namespace,
+//     NewProcessCollector(pid int, namespace string) Collector
-	)
+//
-}
+// Most commonly, it was called as
-
+//
-// NewProcessCollectorPIDFn works like NewProcessCollector but the process ID is
+//     NewProcessCollector(os.Getpid(), "")
-// determined on each collect anew by calling the given pidFn function.
+//
-func NewProcessCollectorPIDFn(
+// The following call of the current version is equivalent to the above:
-	pidFn func() (int, error),
+//
-	namespace string,
+//     NewProcessCollector(ProcessCollectorOpts{})
-) Collector {
+func NewProcessCollector(opts ProcessCollectorOpts) Collector {
 	ns := ""
-	if len(namespace) > 0 {
+	if len(opts.Namespace) > 0 {
-		ns = namespace + "_"
+		ns = opts.Namespace + "_"
 	}
 
-	c := processCollector{
+	c := &processCollector{
-		pidFn:     pidFn,
+		reportErrors: opts.ReportErrors,
-		collectFn: func(chan<- Metric) {},
-
 		cpuTotal: NewDesc(
 			ns+"process_cpu_seconds_total",
 			"Total user and system CPU time spent in seconds.",
@@ -72,6 +101,11 @@ func NewProcessCollectorPIDFn(
 			"Virtual memory size in bytes.",
 			nil, nil,
 		),
+		maxVsize: NewDesc(
+			ns+"process_virtual_memory_max_bytes",
+			"Maximum amount of virtual memory available in bytes.",
+			nil, nil,
+		),
 		rss: NewDesc(
 			ns+"process_resident_memory_bytes",
 			"Resident memory size in bytes.",
@@ -84,12 +118,23 @@ func NewProcessCollectorPIDFn(
 		),
 	}
 
+	if opts.PidFn == nil {
+		pid := os.Getpid()
+		c.pidFn = func() (int, error) { return pid, nil }
+	} else {
+		c.pidFn = opts.PidFn
+	}
+
 	// Set up process metric collection if supported by the runtime.
 	if _, err := procfs.NewStat(); err == nil {
 		c.collectFn = c.processCollect
+	} else {
+		c.collectFn = func(ch chan<- Metric) {
+			c.reportError(ch, nil, errors.New("process metrics not supported on this platform"))
+		}
 	}
 
-	return &c
+	return c
 }
 
 // Describe returns all descriptions of the collector.
@@ -98,6 +143,7 @@ func (c *processCollector) Describe(ch chan<- *Desc) {
 	ch <- c.openFDs
 	ch <- c.maxFDs
 	ch <- c.vsize
+	ch <- c.maxVsize
 	ch <- c.rss
 	ch <- c.startTime
 }
@@ -107,16 +153,16 @@ func (c *processCollector) Collect(ch chan<- Metric) {
 	c.collectFn(ch)
 }
 
-// TODO(ts): Bring back error reporting by reverting 7faf9e7 as soon as the
-// client allows users to configure the error behavior.
 func (c *processCollector) processCollect(ch chan<- Metric) {
 	pid, err := c.pidFn()
 	if err != nil {
+		c.reportError(ch, nil, err)
 		return
 	}
 
 	p, err := procfs.NewProc(pid)
 	if err != nil {
+		c.reportError(ch, nil, err)
 		return
 	}
 
@@ -126,14 +172,33 @@ func (c *processCollector) processCollect(ch chan<- Metric) {
 		ch <- MustNewConstMetric(c.rss, GaugeValue, float64(stat.ResidentMemory()))
 		if startTime, err := stat.StartTime(); err == nil {
 			ch <- MustNewConstMetric(c.startTime, GaugeValue, startTime)
+		} else {
+			c.reportError(ch, c.startTime, err)
 		}
+	} else {
+		c.reportError(ch, nil, err)
 	}
 
 	if fds, err := p.FileDescriptorsLen(); err == nil {
 		ch <- MustNewConstMetric(c.openFDs, GaugeValue, float64(fds))
+	} else {
+		c.reportError(ch, c.openFDs, err)
 	}
 
 	if limits, err := p.NewLimits(); err == nil {
 		ch <- MustNewConstMetric(c.maxFDs, GaugeValue, float64(limits.OpenFiles))
+		ch <- MustNewConstMetric(c.maxVsize, GaugeValue, float64(limits.AddressSpace))
+	} else {
+		c.reportError(ch, nil, err)
 	}
 }
+
+func (c *processCollector) reportError(ch chan<- Metric, desc *Desc, err error) {
+	if !c.reportErrors {
+		return
+	}
+	if desc == nil {
+		desc = NewInvalidDesc(err)
+	}
+	ch <- NewInvalidMetric(desc, err)
+}

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

@@ -76,16 +76,16 @@ type flusherDelegator struct{ *responseWriterDelegator }
 type hijackerDelegator struct{ *responseWriterDelegator }
 type readerFromDelegator struct{ *responseWriterDelegator }
 
-func (d *closeNotifierDelegator) CloseNotify() <-chan bool {
+func (d closeNotifierDelegator) CloseNotify() <-chan bool {
 	return d.ResponseWriter.(http.CloseNotifier).CloseNotify()
 }
-func (d *flusherDelegator) Flush() {
+func (d flusherDelegator) Flush() {
 	d.ResponseWriter.(http.Flusher).Flush()
 }
-func (d *hijackerDelegator) Hijack() (net.Conn, *bufio.ReadWriter, error) {
+func (d hijackerDelegator) Hijack() (net.Conn, *bufio.ReadWriter, error) {
 	return d.ResponseWriter.(http.Hijacker).Hijack()
 }
-func (d *readerFromDelegator) ReadFrom(re io.Reader) (int64, error) {
+func (d readerFromDelegator) ReadFrom(re io.Reader) (int64, error) {
 	if !d.wroteHeader {
 		d.WriteHeader(http.StatusOK)
 	}
@@ -102,34 +102,34 @@ func init() {
 		return d
 	}
 	pickDelegator[closeNotifier] = func(d *responseWriterDelegator) delegator { // 1
-		return &closeNotifierDelegator{d}
+		return closeNotifierDelegator{d}
 	}
 	pickDelegator[flusher] = func(d *responseWriterDelegator) delegator { // 2
-		return &flusherDelegator{d}
+		return flusherDelegator{d}
 	}
 	pickDelegator[flusher+closeNotifier] = func(d *responseWriterDelegator) delegator { // 3
 		return struct {
 			*responseWriterDelegator
 			http.Flusher
 			http.CloseNotifier
-		}{d, &flusherDelegator{d}, &closeNotifierDelegator{d}}
+		}{d, flusherDelegator{d}, closeNotifierDelegator{d}}
 	}
 	pickDelegator[hijacker] = func(d *responseWriterDelegator) delegator { // 4
-		return &hijackerDelegator{d}
+		return hijackerDelegator{d}
 	}
 	pickDelegator[hijacker+closeNotifier] = func(d *responseWriterDelegator) delegator { // 5
 		return struct {
 			*responseWriterDelegator
 			http.Hijacker
 			http.CloseNotifier
-		}{d, &hijackerDelegator{d}, &closeNotifierDelegator{d}}
+		}{d, hijackerDelegator{d}, closeNotifierDelegator{d}}
 	}
 	pickDelegator[hijacker+flusher] = func(d *responseWriterDelegator) delegator { // 6
 		return struct {
 			*responseWriterDelegator
 			http.Hijacker
 			http.Flusher
-		}{d, &hijackerDelegator{d}, &flusherDelegator{d}}
+		}{d, hijackerDelegator{d}, flusherDelegator{d}}
 	}
 	pickDelegator[hijacker+flusher+closeNotifier] = func(d *responseWriterDelegator) delegator { // 7
 		return struct {
@@ -137,7 +137,7 @@ func init() {
 			http.Hijacker
 			http.Flusher
 			http.CloseNotifier
-		}{d, &hijackerDelegator{d}, &flusherDelegator{d}, &closeNotifierDelegator{d}}
+		}{d, hijackerDelegator{d}, flusherDelegator{d}, closeNotifierDelegator{d}}
 	}
 	pickDelegator[readerFrom] = func(d *responseWriterDelegator) delegator { // 8
 		return readerFromDelegator{d}
@@ -147,14 +147,14 @@ func init() {
 			*responseWriterDelegator
 			io.ReaderFrom
 			http.CloseNotifier
-		}{d, &readerFromDelegator{d}, &closeNotifierDelegator{d}}
+		}{d, readerFromDelegator{d}, closeNotifierDelegator{d}}
 	}
 	pickDelegator[readerFrom+flusher] = func(d *responseWriterDelegator) delegator { // 10
 		return struct {
 			*responseWriterDelegator
 			io.ReaderFrom
 			http.Flusher
-		}{d, &readerFromDelegator{d}, &flusherDelegator{d}}
+		}{d, readerFromDelegator{d}, flusherDelegator{d}}
 	}
 	pickDelegator[readerFrom+flusher+closeNotifier] = func(d *responseWriterDelegator) delegator { // 11
 		return struct {
@@ -162,14 +162,14 @@ func init() {
 			io.ReaderFrom
 			http.Flusher
 			http.CloseNotifier
-		}{d, &readerFromDelegator{d}, &flusherDelegator{d}, &closeNotifierDelegator{d}}
+		}{d, readerFromDelegator{d}, flusherDelegator{d}, closeNotifierDelegator{d}}
 	}
 	pickDelegator[readerFrom+hijacker] = func(d *responseWriterDelegator) delegator { // 12
 		return struct {
 			*responseWriterDelegator
 			io.ReaderFrom
 			http.Hijacker
-		}{d, &readerFromDelegator{d}, &hijackerDelegator{d}}
+		}{d, readerFromDelegator{d}, hijackerDelegator{d}}
 	}
 	pickDelegator[readerFrom+hijacker+closeNotifier] = func(d *responseWriterDelegator) delegator { // 13
 		return struct {
@@ -177,7 +177,7 @@ func init() {
 			io.ReaderFrom
 			http.Hijacker
 			http.CloseNotifier
-		}{d, &readerFromDelegator{d}, &hijackerDelegator{d}, &closeNotifierDelegator{d}}
+		}{d, readerFromDelegator{d}, hijackerDelegator{d}, closeNotifierDelegator{d}}
 	}
 	pickDelegator[readerFrom+hijacker+flusher] = func(d *responseWriterDelegator) delegator { // 14
 		return struct {
@@ -185,7 +185,7 @@ func init() {
 			io.ReaderFrom
 			http.Hijacker
 			http.Flusher
-		}{d, &readerFromDelegator{d}, &hijackerDelegator{d}, &flusherDelegator{d}}
+		}{d, readerFromDelegator{d}, hijackerDelegator{d}, flusherDelegator{d}}
 	}
 	pickDelegator[readerFrom+hijacker+flusher+closeNotifier] = func(d *responseWriterDelegator) delegator { // 15
 		return struct {
@@ -194,6 +194,6 @@ func init() {
 			http.Hijacker
 			http.Flusher
 			http.CloseNotifier
-		}{d, &readerFromDelegator{d}, &hijackerDelegator{d}, &flusherDelegator{d}, &closeNotifierDelegator{d}}
+		}{d, readerFromDelegator{d}, hijackerDelegator{d}, flusherDelegator{d}, closeNotifierDelegator{d}}
 	}
 }

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

@@ -22,27 +22,27 @@ import (
 
 type pusherDelegator struct{ *responseWriterDelegator }
 
-func (d *pusherDelegator) Push(target string, opts *http.PushOptions) error {
+func (d pusherDelegator) Push(target string, opts *http.PushOptions) error {
 	return d.ResponseWriter.(http.Pusher).Push(target, opts)
 }
 
 func init() {
 	pickDelegator[pusher] = func(d *responseWriterDelegator) delegator { // 16
-		return &pusherDelegator{d}
+		return pusherDelegator{d}
 	}
 	pickDelegator[pusher+closeNotifier] = func(d *responseWriterDelegator) delegator { // 17
 		return struct {
 			*responseWriterDelegator
 			http.Pusher
 			http.CloseNotifier
-		}{d, &pusherDelegator{d}, &closeNotifierDelegator{d}}
+		}{d, pusherDelegator{d}, closeNotifierDelegator{d}}
 	}
 	pickDelegator[pusher+flusher] = func(d *responseWriterDelegator) delegator { // 18
 		return struct {
 			*responseWriterDelegator
 			http.Pusher
 			http.Flusher
-		}{d, &pusherDelegator{d}, &flusherDelegator{d}}
+		}{d, pusherDelegator{d}, flusherDelegator{d}}
 	}
 	pickDelegator[pusher+flusher+closeNotifier] = func(d *responseWriterDelegator) delegator { // 19
 		return struct {
@@ -50,14 +50,14 @@ func init() {
 			http.Pusher
 			http.Flusher
 			http.CloseNotifier
-		}{d, &pusherDelegator{d}, &flusherDelegator{d}, &closeNotifierDelegator{d}}
+		}{d, pusherDelegator{d}, flusherDelegator{d}, closeNotifierDelegator{d}}
 	}
 	pickDelegator[pusher+hijacker] = func(d *responseWriterDelegator) delegator { // 20
 		return struct {
 			*responseWriterDelegator
 			http.Pusher
 			http.Hijacker
-		}{d, &pusherDelegator{d}, &hijackerDelegator{d}}
+		}{d, pusherDelegator{d}, hijackerDelegator{d}}
 	}
 	pickDelegator[pusher+hijacker+closeNotifier] = func(d *responseWriterDelegator) delegator { // 21
 		return struct {
@@ -65,7 +65,7 @@ func init() {
 			http.Pusher
 			http.Hijacker
 			http.CloseNotifier
-		}{d, &pusherDelegator{d}, &hijackerDelegator{d}, &closeNotifierDelegator{d}}
+		}{d, pusherDelegator{d}, hijackerDelegator{d}, closeNotifierDelegator{d}}
 	}
 	pickDelegator[pusher+hijacker+flusher] = func(d *responseWriterDelegator) delegator { // 22
 		return struct {
@@ -73,7 +73,7 @@ func init() {
 			http.Pusher
 			http.Hijacker
 			http.Flusher
-		}{d, &pusherDelegator{d}, &hijackerDelegator{d}, &flusherDelegator{d}}
+		}{d, pusherDelegator{d}, hijackerDelegator{d}, flusherDelegator{d}}
 	}
 	pickDelegator[pusher+hijacker+flusher+closeNotifier] = func(d *responseWriterDelegator) delegator { //23
 		return struct {
@@ -82,14 +82,14 @@ func init() {
 			http.Hijacker
 			http.Flusher
 			http.CloseNotifier
-		}{d, &pusherDelegator{d}, &hijackerDelegator{d}, &flusherDelegator{d}, &closeNotifierDelegator{d}}
+		}{d, pusherDelegator{d}, hijackerDelegator{d}, flusherDelegator{d}, closeNotifierDelegator{d}}
 	}
 	pickDelegator[pusher+readerFrom] = func(d *responseWriterDelegator) delegator { // 24
 		return struct {
 			*responseWriterDelegator
 			http.Pusher
 			io.ReaderFrom
-		}{d, &pusherDelegator{d}, &readerFromDelegator{d}}
+		}{d, pusherDelegator{d}, readerFromDelegator{d}}
 	}
 	pickDelegator[pusher+readerFrom+closeNotifier] = func(d *responseWriterDelegator) delegator { // 25
 		return struct {
@@ -97,7 +97,7 @@ func init() {
 			http.Pusher
 			io.ReaderFrom
 			http.CloseNotifier
-		}{d, &pusherDelegator{d}, &readerFromDelegator{d}, &closeNotifierDelegator{d}}
+		}{d, pusherDelegator{d}, readerFromDelegator{d}, closeNotifierDelegator{d}}
 	}
 	pickDelegator[pusher+readerFrom+flusher] = func(d *responseWriterDelegator) delegator { // 26
 		return struct {
@@ -105,7 +105,7 @@ func init() {
 			http.Pusher
 			io.ReaderFrom
 			http.Flusher
-		}{d, &pusherDelegator{d}, &readerFromDelegator{d}, &flusherDelegator{d}}
+		}{d, pusherDelegator{d}, readerFromDelegator{d}, flusherDelegator{d}}
 	}
 	pickDelegator[pusher+readerFrom+flusher+closeNotifier] = func(d *responseWriterDelegator) delegator { // 27
 		return struct {
@@ -114,7 +114,7 @@ func init() {
 			io.ReaderFrom
 			http.Flusher
 			http.CloseNotifier
-		}{d, &pusherDelegator{d}, &readerFromDelegator{d}, &flusherDelegator{d}, &closeNotifierDelegator{d}}
+		}{d, pusherDelegator{d}, readerFromDelegator{d}, flusherDelegator{d}, closeNotifierDelegator{d}}
 	}
 	pickDelegator[pusher+readerFrom+hijacker] = func(d *responseWriterDelegator) delegator { // 28
 		return struct {
@@ -122,7 +122,7 @@ func init() {
 			http.Pusher
 			io.ReaderFrom
 			http.Hijacker
-		}{d, &pusherDelegator{d}, &readerFromDelegator{d}, &hijackerDelegator{d}}
+		}{d, pusherDelegator{d}, readerFromDelegator{d}, hijackerDelegator{d}}
 	}
 	pickDelegator[pusher+readerFrom+hijacker+closeNotifier] = func(d *responseWriterDelegator) delegator { // 29
 		return struct {
@@ -131,7 +131,7 @@ func init() {
 			io.ReaderFrom
 			http.Hijacker
 			http.CloseNotifier
-		}{d, &pusherDelegator{d}, &readerFromDelegator{d}, &hijackerDelegator{d}, &closeNotifierDelegator{d}}
+		}{d, pusherDelegator{d}, readerFromDelegator{d}, hijackerDelegator{d}, closeNotifierDelegator{d}}
 	}
 	pickDelegator[pusher+readerFrom+hijacker+flusher] = func(d *responseWriterDelegator) delegator { // 30
 		return struct {
@@ -140,7 +140,7 @@ func init() {
 			io.ReaderFrom
 			http.Hijacker
 			http.Flusher
-		}{d, &pusherDelegator{d}, &readerFromDelegator{d}, &hijackerDelegator{d}, &flusherDelegator{d}}
+		}{d, pusherDelegator{d}, readerFromDelegator{d}, hijackerDelegator{d}, flusherDelegator{d}}
 	}
 	pickDelegator[pusher+readerFrom+hijacker+flusher+closeNotifier] = func(d *responseWriterDelegator) delegator { // 31
 		return struct {
@@ -150,7 +150,7 @@ func init() {
 			http.Hijacker
 			http.Flusher
 			http.CloseNotifier
-		}{d, &pusherDelegator{d}, &readerFromDelegator{d}, &hijackerDelegator{d}, &flusherDelegator{d}, &closeNotifierDelegator{d}}
+		}{d, pusherDelegator{d}, readerFromDelegator{d}, hijackerDelegator{d}, flusherDelegator{d}, closeNotifierDelegator{d}}
 	}
 }
 

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

@@ -15,17 +15,18 @@ package prometheus
 
 import (
 	"bytes"
-	"errors"
 	"fmt"
-	"os"
 	"runtime"
 	"sort"
+	"strings"
 	"sync"
 	"unicode/utf8"
 
 	"github.com/golang/protobuf/proto"
 
 	dto "github.com/prometheus/client_model/go"
+
+	"github.com/prometheus/client_golang/prometheus/internal"
 )
 
 const (
@@ -52,7 +53,7 @@ var (
 )
 
 func init() {
-	MustRegister(NewProcessCollector(os.Getpid(), ""))
+	MustRegister(NewProcessCollector(ProcessCollectorOpts{}))
 	MustRegister(NewGoCollector())
 }
 
@@ -68,7 +69,8 @@ func NewRegistry() *Registry {
 
 // NewPedanticRegistry returns a registry that checks during collection if each
 // collected Metric is consistent with its reported Desc, and if the Desc has
-// actually been registered with the registry.
+// actually been registered with the registry. Unchecked Collectors (those whose
+// Describe methed does not yield any descriptors) are excluded from the check.
 //
 // Usually, a Registry will be happy as long as the union of all collected
 // Metrics is consistent and valid even if some metrics are not consistent with
@@ -98,6 +100,14 @@ type Registerer interface {
 	// returned error is an instance of AlreadyRegisteredError, which
 	// contains the previously registered Collector.
 	//
+	// A Collector whose Describe method does not yield any Desc is treated
+	// as unchecked. Registration will always succeed. No check for
+	// re-registering (see previous paragraph) is performed. Thus, the
+	// caller is responsible for not double-registering the same unchecked
+	// Collector, and for providing a Collector that will not cause
+	// inconsistent metrics on collection. (This would lead to scrape
+	// errors.)
+	//
 	// It is in general not safe to register the same Collector multiple
 	// times concurrently.
 	Register(Collector) error
@@ -108,7 +118,9 @@ type Registerer interface {
 	// Unregister unregisters the Collector that equals the Collector passed
 	// in as an argument.  (Two Collectors are considered equal if their
 	// Describe method yields the same set of descriptors.) The function
-	// returns whether a Collector was unregistered.
+	// returns whether a Collector was unregistered. Note that an unchecked
+	// Collector cannot be unregistered (as its Describe method does not
+	// yield any descriptor).
 	//
 	// Note that even after unregistering, it will not be possible to
 	// register a new Collector that is inconsistent with the unregistered
@@ -243,6 +255,7 @@ type Registry struct {
 	collectorsByID        map[uint64]Collector // ID is a hash of the descIDs.
 	descIDs               map[uint64]struct{}
 	dimHashesByName       map[string]uint64
+	uncheckedCollectors   []Collector
 	pedanticChecksEnabled bool
 }
 
@@ -300,9 +313,10 @@ func (r *Registry) Register(c Collector) error {
 			}
 		}
 	}
-	// Did anything happen at all?
+	// A Collector yielding no Desc at all is considered unchecked.
 	if len(newDescIDs) == 0 {
-		return errors.New("collector has no descriptors")
+		r.uncheckedCollectors = append(r.uncheckedCollectors, c)
+		return nil
 	}
 	if existing, exists := r.collectorsByID[collectorID]; exists {
 		return AlreadyRegisteredError{
@@ -376,19 +390,24 @@ func (r *Registry) MustRegister(cs ...Collector) {
 // Gather implements Gatherer.
 func (r *Registry) Gather() ([]*dto.MetricFamily, error) {
 	var (
-		metricChan        = make(chan Metric, capMetricChan)
+		checkedMetricChan   = make(chan Metric, capMetricChan)
-		metricHashes      = map[uint64]struct{}{}
+		uncheckedMetricChan = make(chan Metric, capMetricChan)
-		wg                sync.WaitGroup
+		metricHashes        = map[uint64]struct{}{}
-		errs              MultiError          // The collected errors to return in the end.
+		wg                  sync.WaitGroup
-		registeredDescIDs map[uint64]struct{} // Only used for pedantic checks
+		errs                MultiError          // The collected errors to return in the end.
+		registeredDescIDs   map[uint64]struct{} // Only used for pedantic checks
 	)
 
 	r.mtx.RLock()
-	goroutineBudget := len(r.collectorsByID)
+	goroutineBudget := len(r.collectorsByID) + len(r.uncheckedCollectors)
 	metricFamiliesByName := make(map[string]*dto.MetricFamily, len(r.dimHashesByName))
-	collectors := make(chan Collector, len(r.collectorsByID))
+	checkedCollectors := make(chan Collector, len(r.collectorsByID))
+	uncheckedCollectors := make(chan Collector, len(r.uncheckedCollectors))
 	for _, collector := range r.collectorsByID {
-		collectors <- collector
+		checkedCollectors <- collector
+	}
+	for _, collector := range r.uncheckedCollectors {
+		uncheckedCollectors <- collector
 	}
 	// In case pedantic checks are enabled, we have to copy the map before
 	// giving up the RLock.
@@ -405,12 +424,14 @@ func (r *Registry) Gather() ([]*dto.MetricFamily, error) {
 	collectWorker := func() {
 		for {
 			select {
-			case collector := <-collectors:
+			case collector := <-checkedCollectors:
-				collector.Collect(metricChan)
+				collector.Collect(checkedMetricChan)
-				wg.Done()
+			case collector := <-uncheckedCollectors:
+				collector.Collect(uncheckedMetricChan)
 			default:
 				return
 			}
+			wg.Done()
 		}
 	}
 
@@ -418,53 +439,96 @@ func (r *Registry) Gather() ([]*dto.MetricFamily, error) {
 	go collectWorker()
 	goroutineBudget--
 
-	// Close the metricChan once all collectors are collected.
+	// Close checkedMetricChan and uncheckedMetricChan once all collectors
+	// are collected.
 	go func() {
 		wg.Wait()
-		close(metricChan)
+		close(checkedMetricChan)
+		close(uncheckedMetricChan)
 	}()
 
-	// Drain metricChan in case of premature return.
+	// Drain checkedMetricChan and uncheckedMetricChan in case of premature return.
 	defer func() {
-		for range metricChan {
+		if checkedMetricChan != nil {
+			for range checkedMetricChan {
+			}
+		}
+		if uncheckedMetricChan != nil {
+			for range uncheckedMetricChan {
+			}
 		}
 	}()
 
-collectLoop:
+	// Copy the channel references so we can nil them out later to remove
+	// them from the select statements below.
+	cmc := checkedMetricChan
+	umc := uncheckedMetricChan
+
 	for {
 		select {
-		case metric, ok := <-metricChan:
+		case metric, ok := <-cmc:
 			if !ok {
-				// metricChan is closed, we are done.
+				cmc = nil
-				break collectLoop
+				break
 			}
 			errs.Append(processMetric(
 				metric, metricFamiliesByName,
 				metricHashes,
 				registeredDescIDs,
 			))
+		case metric, ok := <-umc:
+			if !ok {
+				umc = nil
+				break
+			}
+			errs.Append(processMetric(
+				metric, metricFamiliesByName,
+				metricHashes,
+				nil,
+			))
 		default:
-			if goroutineBudget <= 0 || len(collectors) == 0 {
+			if goroutineBudget <= 0 || len(checkedCollectors)+len(uncheckedCollectors) == 0 {
 				// All collectors are already being worked on or
 				// we have already as many goroutines started as
-				// there are collectors. Just process metrics
+				// there are collectors. Do the same as above,
-				// from now on.
+				// just without the default.
-				for metric := range metricChan {
+				select {
+				case metric, ok := <-cmc:
+					if !ok {
+						cmc = nil
+						break
+					}
 					errs.Append(processMetric(
 						metric, metricFamiliesByName,
 						metricHashes,
 						registeredDescIDs,
 					))
+				case metric, ok := <-umc:
+					if !ok {
+						umc = nil
+						break
+					}
+					errs.Append(processMetric(
+						metric, metricFamiliesByName,
+						metricHashes,
+						nil,
+					))
 				}
-				break collectLoop
+				break
 			}
 			// Start more workers.
 			go collectWorker()
 			goroutineBudget--
 			runtime.Gosched()
 		}
+		// Once both checkedMetricChan and uncheckdMetricChan are closed
+		// and drained, the contraption above will nil out cmc and umc,
+		// and then we can leave the collect loop here.
+		if cmc == nil && umc == nil {
+			break
+		}
 	}
-	return normalizeMetricFamilies(metricFamiliesByName), errs.MaybeUnwrap()
+	return internal.NormalizeMetricFamilies(metricFamiliesByName), errs.MaybeUnwrap()
 }
 
 // processMetric is an internal helper method only used by the Gather method.
@@ -475,12 +539,17 @@ func processMetric(
 	registeredDescIDs map[uint64]struct{},
 ) error {
 	desc := metric.Desc()
+	// Wrapped metrics collected by an unchecked Collector can have an
+	// invalid Desc.
+	if desc.err != nil {
+		return desc.err
+	}
 	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 ok { // Existing name.
 		if metricFamily.GetHelp() != desc.help {
 			return fmt.Errorf(
 				"collected metric %s %s has help %q but should have %q",
@@ -527,7 +596,7 @@ func processMetric(
 		default:
 			panic("encountered MetricFamily with invalid type")
 		}
-	} else {
+	} else { // New name.
 		metricFamily = &dto.MetricFamily{}
 		metricFamily.Name = proto.String(desc.fqName)
 		metricFamily.Help = proto.String(desc.help)
@@ -546,6 +615,9 @@ func processMetric(
 		default:
 			return fmt.Errorf("empty metric collected: %s", dtoMetric)
 		}
+		if err := checkSuffixCollisions(metricFamily, metricFamiliesByName); err != nil {
+			return err
+		}
 		metricFamiliesByName[desc.fqName] = metricFamily
 	}
 	if err := checkMetricConsistency(metricFamily, dtoMetric, metricHashes); err != nil {
@@ -626,6 +698,10 @@ func (gs Gatherers) Gather() ([]*dto.MetricFamily, error) {
 				existingMF.Name = mf.Name
 				existingMF.Help = mf.Help
 				existingMF.Type = mf.Type
+				if err := checkSuffixCollisions(existingMF, metricFamiliesByName); err != nil {
+					errs = append(errs, err)
+					continue
+				}
 				metricFamiliesByName[mf.GetName()] = existingMF
 			}
 			for _, m := range mf.Metric {
@@ -637,72 +713,67 @@ func (gs Gatherers) Gather() ([]*dto.MetricFamily, error) {
 			}
 		}
 	}
-	return normalizeMetricFamilies(metricFamiliesByName), errs.MaybeUnwrap()
+	return internal.NormalizeMetricFamilies(metricFamiliesByName), errs.MaybeUnwrap()
 }
 
-// metricSorter is a sortable slice of *dto.Metric.
+// checkSuffixCollisions checks for collisions with the “magic” suffixes the
-type metricSorter []*dto.Metric
+// Prometheus text format and the internal metric representation of the
-
+// Prometheus server add while flattening Summaries and Histograms.
-func (s metricSorter) Len() int {
+func checkSuffixCollisions(mf *dto.MetricFamily, mfs map[string]*dto.MetricFamily) error {
-	return len(s)
+	var (
-}
+		newName              = mf.GetName()
-
+		newType              = mf.GetType()
-func (s metricSorter) Swap(i, j int) {
+		newNameWithoutSuffix = ""
-	s[i], s[j] = s[j], s[i]
+	)
-}
+	switch {
-
+	case strings.HasSuffix(newName, "_count"):
-func (s metricSorter) Less(i, j int) bool {
+		newNameWithoutSuffix = newName[:len(newName)-6]
-	if len(s[i].Label) != len(s[j].Label) {
+	case strings.HasSuffix(newName, "_sum"):
-		// This should not happen. The metrics are
+		newNameWithoutSuffix = newName[:len(newName)-4]
-		// inconsistent. However, we have to deal with the fact, as
+	case strings.HasSuffix(newName, "_bucket"):
-		// people might use custom collectors or metric family injection
+		newNameWithoutSuffix = newName[:len(newName)-7]
-		// to create inconsistent metrics. So let's simply compare the
-		// number of labels in this case. That will still yield
-		// reproducible sorting.
-		return len(s[i].Label) < len(s[j].Label)
 	}
-	for n, lp := range s[i].Label {
+	if newNameWithoutSuffix != "" {
-		vi := lp.GetValue()
+		if existingMF, ok := mfs[newNameWithoutSuffix]; ok {
-		vj := s[j].Label[n].GetValue()
+			switch existingMF.GetType() {
-		if vi != vj {
+			case dto.MetricType_SUMMARY:
-			return vi < vj
+				if !strings.HasSuffix(newName, "_bucket") {
+					return fmt.Errorf(
+						"collected metric named %q collides with previously collected summary named %q",
+						newName, newNameWithoutSuffix,
+					)
+				}
+			case dto.MetricType_HISTOGRAM:
+				return fmt.Errorf(
+					"collected metric named %q collides with previously collected histogram named %q",
+					newName, newNameWithoutSuffix,
+				)
+			}
 		}
 	}
-
+	if newType == dto.MetricType_SUMMARY || newType == dto.MetricType_HISTOGRAM {
-	// We should never arrive here. Multiple metrics with the same
+		if _, ok := mfs[newName+"_count"]; ok {
-	// label set in the same scrape will lead to undefined ingestion
+			return fmt.Errorf(
-	// behavior. However, as above, we have to provide stable sorting
+				"collected histogram or summary named %q collides with previously collected metric named %q",
-	// here, even for inconsistent metrics. So sort equal metrics
+				newName, newName+"_count",
-	// by their timestamp, with missing timestamps (implying "now")
+			)
-	// coming last.
+		}
-	if s[i].TimestampMs == nil {
+		if _, ok := mfs[newName+"_sum"]; ok {
-		return false
+			return fmt.Errorf(
-	}
+				"collected histogram or summary named %q collides with previously collected metric named %q",
-	if s[j].TimestampMs == nil {
+				newName, newName+"_sum",
-		return true
+			)
-	}
-	return s[i].GetTimestampMs() < s[j].GetTimestampMs()
-}
-
-// 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 {
-	for _, mf := range metricFamiliesByName {
-		sort.Sort(metricSorter(mf.Metric))
-	}
-	names := make([]string, 0, len(metricFamiliesByName))
-	for name, mf := range metricFamiliesByName {
-		if len(mf.Metric) > 0 {
-			names = append(names, name)
 		}
 	}
-	sort.Strings(names)
+	if newType == dto.MetricType_HISTOGRAM {
-	result := make([]*dto.MetricFamily, 0, len(names))
+		if _, ok := mfs[newName+"_bucket"]; ok {
-	for _, name := range names {
+			return fmt.Errorf(
-		result = append(result, metricFamiliesByName[name])
+				"collected histogram named %q collides with previously collected metric named %q",
+				newName, newName+"_bucket",
+			)
+		}
 	}
-	return result
+	return nil
 }
 
 // checkMetricConsistency checks if the provided Metric is consistent with the
@@ -721,14 +792,28 @@ func checkMetricConsistency(
 		metricFamily.GetType() == dto.MetricType_HISTOGRAM && dtoMetric.Histogram == nil ||
 		metricFamily.GetType() == dto.MetricType_UNTYPED && dtoMetric.Untyped == nil {
 		return fmt.Errorf(
-			"collected metric %s %s is not a %s",
+			"collected metric %q { %s} is not a %s",
 			metricFamily.GetName(), dtoMetric, metricFamily.GetType(),
 		)
 	}
 
 	for _, labelPair := range dtoMetric.GetLabel() {
+		if !checkLabelName(labelPair.GetName()) {
+			return fmt.Errorf(
+				"collected metric %q { %s} has a label with an invalid name: %s",
+				metricFamily.GetName(), dtoMetric, labelPair.GetName(),
+			)
+		}
+		if dtoMetric.Summary != nil && labelPair.GetName() == quantileLabel {
+			return fmt.Errorf(
+				"collected metric %q { %s} must not have an explicit %q label",
+				metricFamily.GetName(), dtoMetric, quantileLabel,
+			)
+		}
 		if !utf8.ValidString(labelPair.GetValue()) {
-			return fmt.Errorf("collected metric's label %s is not utf8: %#v", labelPair.GetName(), labelPair.GetValue())
+			return fmt.Errorf(
+				"collected metric %q { %s} has a label named %q whose value is not utf8: %#v",
+				metricFamily.GetName(), dtoMetric, labelPair.GetName(), labelPair.GetValue())
 		}
 	}
 
@@ -738,7 +823,7 @@ func checkMetricConsistency(
 	h = hashAddByte(h, separatorByte)
 	// Make sure label pairs are sorted. We depend on it for the consistency
 	// check.
-	sort.Sort(LabelPairSorter(dtoMetric.Label))
+	sort.Sort(labelPairSorter(dtoMetric.Label))
 	for _, lp := range dtoMetric.Label {
 		h = hashAdd(h, lp.GetName())
 		h = hashAddByte(h, separatorByte)
@@ -747,7 +832,7 @@ func checkMetricConsistency(
 	}
 	if _, exists := metricHashes[h]; exists {
 		return fmt.Errorf(
-			"collected metric %s %s was collected before with the same name and label values",
+			"collected metric %q { %s} was collected before with the same name and label values",
 			metricFamily.GetName(), dtoMetric,
 		)
 	}
@@ -782,7 +867,7 @@ func checkDescConsistency(
 			metricFamily.GetName(), dtoMetric, desc,
 		)
 	}
-	sort.Sort(LabelPairSorter(lpsFromDesc))
+	sort.Sort(labelPairSorter(lpsFromDesc))
 	for i, lpFromDesc := range lpsFromDesc {
 		lpFromMetric := dtoMetric.Label[i]
 		if lpFromDesc.GetName() != lpFromMetric.GetName() ||

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

@@ -37,7 +37,7 @@ const quantileLabel = "quantile"
 // A typical use-case is the observation of request latencies. By default, a
 // Summary provides the median, the 90th and the 99th percentile of the latency
 // as rank estimations. However, the default behavior will change in the
-// upcoming v0.10 of the library. There will be no rank estiamtions at all by
+// upcoming v0.10 of the library. There will be no rank estimations at all by
 // default. For a sane transition, it is recommended to set the desired rank
 // estimations explicitly.
 //
@@ -81,10 +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. While all other fields
+// mandatory to set Name to a non-empty string. While all other fields are
-// are optional and can safely be left at their zero value, it is recommended to
+// optional and can safely be left at their zero value, it is recommended to set
-// explicitly set the Objectives field to the desired value as the default value
+// a help string and to explicitly set the Objectives field to the desired value
-// will change in the upcoming v0.10 of the library.
+// 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
@@ -95,7 +95,7 @@ type SummaryOpts struct {
 	Subsystem string
 	Name      string
 
-	// Help provides information about this Summary. Mandatory!
+	// Help provides information about this Summary.
 	//
 	// Metrics with the same fully-qualified name must have the same Help
 	// string.
@@ -105,6 +105,11 @@ type SummaryOpts struct {
 	// with the same fully-qualified name must have the same label names in
 	// their ConstLabels.
 	//
+	// Due to the way a Summary is represented in the Prometheus text format
+	// and how it is handled by the Prometheus server internally, “quantile”
+	// is an illegal label name. Construction of a Summary or SummaryVec
+	// will panic if this label name is used in ConstLabels.
+	//
 	// ConstLabels are only used rarely. In particular, do not use them to
 	// attach the same labels to all your metrics. Those use cases are
 	// better covered by target labels set by the scraping Prometheus
@@ -402,7 +407,16 @@ type SummaryVec struct {
 
 // NewSummaryVec creates a new SummaryVec based on the provided SummaryOpts and
 // partitioned by the given label names.
+//
+// Due to the way a Summary is represented in the Prometheus text format and how
+// it is handled by the Prometheus server internally, “quantile” is an illegal
+// label name. NewSummaryVec will panic if this label name is used.
 func NewSummaryVec(opts SummaryOpts, labelNames []string) *SummaryVec {
+	for _, ln := range labelNames {
+		if ln == quantileLabel {
+			panic(errQuantileLabelNotAllowed)
+		}
+	}
 	desc := NewDesc(
 		BuildFQName(opts.Namespace, opts.Subsystem, opts.Name),
 		opts.Help,
@@ -572,7 +586,7 @@ func (s *constSummary) Write(out *dto.Metric) error {
 //     map[float64]float64{0.5: 0.23, 0.99: 0.56}
 //
 // NewConstSummary returns an error if the length of labelValues is not
-// consistent with the variable labels in Desc.
+// consistent with the variable labels in Desc or if Desc is invalid.
 func NewConstSummary(
 	desc *Desc,
 	count uint64,
@@ -580,6 +594,9 @@ func NewConstSummary(
 	quantiles map[float64]float64,
 	labelValues ...string,
 ) (Metric, error) {
+	if desc.err != nil {
+		return nil, desc.err
+	}
 	if err := validateLabelValues(labelValues, len(desc.variableLabels)); err != nil {
 		return nil, err
 	}

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

@@ -17,9 +17,9 @@ import (
 	"fmt"
 	"sort"
 
-	dto "github.com/prometheus/client_model/go"
-
 	"github.com/golang/protobuf/proto"
+
+	dto "github.com/prometheus/client_model/go"
 )
 
 // ValueType is an enumeration of metric types that represent a simple value.
@@ -77,8 +77,12 @@ func (v *valueFunc) Write(out *dto.Metric) error {
 // operations. However, when implementing custom Collectors, it is useful as a
 // throw-away metric that is generated on the fly to send it to Prometheus in
 // the Collect method. NewConstMetric returns an error if the length of
-// labelValues is not consistent with the variable labels in Desc.
+// labelValues is not consistent with the variable labels in Desc or if Desc is
+// invalid.
 func NewConstMetric(desc *Desc, valueType ValueType, value float64, labelValues ...string) (Metric, error) {
+	if desc.err != nil {
+		return nil, desc.err
+	}
 	if err := validateLabelValues(labelValues, len(desc.variableLabels)); err != nil {
 		return nil, err
 	}
@@ -153,6 +157,6 @@ func makeLabelPairs(desc *Desc, labelValues []string) []*dto.LabelPair {
 		})
 	}
 	labelPairs = append(labelPairs, desc.constLabelPairs...)
-	sort.Sort(LabelPairSorter(labelPairs))
+	sort.Sort(labelPairSorter(labelPairs))
 	return labelPairs
 }

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

@@ -0,0 +1,179 @@
+// 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 prometheus
+
+import (
+	"fmt"
+	"sort"
+
+	"github.com/golang/protobuf/proto"
+
+	dto "github.com/prometheus/client_model/go"
+)
+
+// WrapRegistererWith returns a Registerer wrapping the provided
+// Registerer. Collectors registered with the returned Registerer will be
+// registered with the wrapped Registerer in a modified way. The modified
+// Collector adds the provided Labels to all Metrics it collects (as
+// ConstLabels). The Metrics collected by the unmodified Collector must not
+// duplicate any of those labels.
+//
+// WrapRegistererWith provides a way to add fixed labels to a subset of
+// Collectors. It should not be used to add fixed labels to all metrics exposed.
+//
+// The Collector example demonstrates a use of WrapRegistererWith.
+func WrapRegistererWith(labels Labels, reg Registerer) Registerer {
+	return &wrappingRegisterer{
+		wrappedRegisterer: reg,
+		labels:            labels,
+	}
+}
+
+// WrapRegistererWithPrefix returns a Registerer wrapping the provided
+// Registerer. Collectors registered with the returned Registerer will be
+// registered with the wrapped Registerer in a modified way. The modified
+// Collector adds the provided prefix to the name of all Metrics it collects.
+//
+// WrapRegistererWithPrefix is useful to have one place to prefix all metrics of
+// a sub-system. To make this work, register metrics of the sub-system with the
+// wrapping Registerer returned by WrapRegistererWithPrefix. It is rarely useful
+// to use the same prefix for all metrics exposed. In particular, do not prefix
+// metric names that are standardized across applications, as that would break
+// horizontal monitoring, for example the metrics provided by the Go collector
+// (see NewGoCollector) and the process collector (see NewProcessCollector). (In
+// fact, those metrics are already prefixed with “go_” or “process_”,
+// respectively.)
+func WrapRegistererWithPrefix(prefix string, reg Registerer) Registerer {
+	return &wrappingRegisterer{
+		wrappedRegisterer: reg,
+		prefix:            prefix,
+	}
+}
+
+type wrappingRegisterer struct {
+	wrappedRegisterer Registerer
+	prefix            string
+	labels            Labels
+}
+
+func (r *wrappingRegisterer) Register(c Collector) error {
+	return r.wrappedRegisterer.Register(&wrappingCollector{
+		wrappedCollector: c,
+		prefix:           r.prefix,
+		labels:           r.labels,
+	})
+}
+
+func (r *wrappingRegisterer) MustRegister(cs ...Collector) {
+	for _, c := range cs {
+		if err := r.Register(c); err != nil {
+			panic(err)
+		}
+	}
+}
+
+func (r *wrappingRegisterer) Unregister(c Collector) bool {
+	return r.wrappedRegisterer.Unregister(&wrappingCollector{
+		wrappedCollector: c,
+		prefix:           r.prefix,
+		labels:           r.labels,
+	})
+}
+
+type wrappingCollector struct {
+	wrappedCollector Collector
+	prefix           string
+	labels           Labels
+}
+
+func (c *wrappingCollector) Collect(ch chan<- Metric) {
+	wrappedCh := make(chan Metric)
+	go func() {
+		c.wrappedCollector.Collect(wrappedCh)
+		close(wrappedCh)
+	}()
+	for m := range wrappedCh {
+		ch <- &wrappingMetric{
+			wrappedMetric: m,
+			prefix:        c.prefix,
+			labels:        c.labels,
+		}
+	}
+}
+
+func (c *wrappingCollector) Describe(ch chan<- *Desc) {
+	wrappedCh := make(chan *Desc)
+	go func() {
+		c.wrappedCollector.Describe(wrappedCh)
+		close(wrappedCh)
+	}()
+	for desc := range wrappedCh {
+		ch <- wrapDesc(desc, c.prefix, c.labels)
+	}
+}
+
+type wrappingMetric struct {
+	wrappedMetric Metric
+	prefix        string
+	labels        Labels
+}
+
+func (m *wrappingMetric) Desc() *Desc {
+	return wrapDesc(m.wrappedMetric.Desc(), m.prefix, m.labels)
+}
+
+func (m *wrappingMetric) Write(out *dto.Metric) error {
+	if err := m.wrappedMetric.Write(out); err != nil {
+		return err
+	}
+	if len(m.labels) == 0 {
+		// No wrapping labels.
+		return nil
+	}
+	for ln, lv := range m.labels {
+		out.Label = append(out.Label, &dto.LabelPair{
+			Name:  proto.String(ln),
+			Value: proto.String(lv),
+		})
+	}
+	sort.Sort(labelPairSorter(out.Label))
+	return nil
+}
+
+func wrapDesc(desc *Desc, prefix string, labels Labels) *Desc {
+	constLabels := Labels{}
+	for _, lp := range desc.constLabelPairs {
+		constLabels[*lp.Name] = *lp.Value
+	}
+	for ln, lv := range labels {
+		if _, alreadyUsed := constLabels[ln]; alreadyUsed {
+			return &Desc{
+				fqName:          desc.fqName,
+				help:            desc.help,
+				variableLabels:  desc.variableLabels,
+				constLabelPairs: desc.constLabelPairs,
+				err:             fmt.Errorf("attempted wrapping with already existing label name %q", ln),
+			}
+		}
+		constLabels[ln] = lv
+	}
+	// NewDesc will do remaining validations.
+	newDesc := NewDesc(prefix+desc.fqName, desc.help, desc.variableLabels, constLabels)
+	// Propagate errors if there was any. This will override any errer
+	// created by NewDesc above, i.e. earlier errors get precedence.
+	if desc.err != nil {
+		newDesc.err = desc.err
+	}
+	return newDesc
+}

vendor/github.com/prometheus/client_model/go/metrics.pb.go

@@ -1,34 +1,23 @@
-// Code generated by protoc-gen-go.
+// Code generated by protoc-gen-go. DO NOT EDIT.
 // source: metrics.proto
-// DO NOT EDIT!
 
-/*
+package io_prometheus_client // import "github.com/prometheus/client_model/go"
-Package io_prometheus_client is a generated protocol buffer package.
-
-It is generated from these files:
-	metrics.proto
-
-It has these top-level messages:
-	LabelPair
-	Gauge
-	Counter
-	Quantile
-	Summary
-	Untyped
-	Histogram
-	Bucket
-	Metric
-	MetricFamily
-*/
-package io_prometheus_client
 
 import proto "github.com/golang/protobuf/proto"
+import fmt "fmt"
 import math "math"
 
 // Reference imports to suppress errors if they are not otherwise used.
 var _ = proto.Marshal
+var _ = fmt.Errorf
 var _ = math.Inf
 
+// This is a compile-time assertion to ensure that this generated file
+// is compatible with the proto package it is being compiled against.
+// A compilation error at this line likely means your copy of the
+// proto package needs to be updated.
+const _ = proto.ProtoPackageIsVersion2 // please upgrade the proto package
+
 type MetricType int32
 
 const (
@@ -70,16 +59,41 @@ func (x *MetricType) UnmarshalJSON(data []byte) error {
 	*x = MetricType(value)
 	return nil
 }
+func (MetricType) EnumDescriptor() ([]byte, []int) {
+	return fileDescriptor_metrics_c97c9a2b9560cb8f, []int{0}
+}
 
 type LabelPair struct {
-	Name             *string `protobuf:"bytes,1,opt,name=name" json:"name,omitempty"`
+	Name                 *string  `protobuf:"bytes,1,opt,name=name" json:"name,omitempty"`
-	Value            *string `protobuf:"bytes,2,opt,name=value" json:"value,omitempty"`
+	Value                *string  `protobuf:"bytes,2,opt,name=value" json:"value,omitempty"`
-	XXX_unrecognized []byte  `json:"-"`
+	XXX_NoUnkeyedLiteral struct{} `json:"-"`
+	XXX_unrecognized     []byte   `json:"-"`
+	XXX_sizecache        int32    `json:"-"`
 }
 
 func (m *LabelPair) Reset()         { *m = LabelPair{} }
 func (m *LabelPair) String() string { return proto.CompactTextString(m) }
 func (*LabelPair) ProtoMessage()    {}
+func (*LabelPair) Descriptor() ([]byte, []int) {
+	return fileDescriptor_metrics_c97c9a2b9560cb8f, []int{0}
+}
+func (m *LabelPair) XXX_Unmarshal(b []byte) error {
+	return xxx_messageInfo_LabelPair.Unmarshal(m, b)
+}
+func (m *LabelPair) XXX_Marshal(b []byte, deterministic bool) ([]byte, error) {
+	return xxx_messageInfo_LabelPair.Marshal(b, m, deterministic)
+}
+func (dst *LabelPair) XXX_Merge(src proto.Message) {
+	xxx_messageInfo_LabelPair.Merge(dst, src)
+}
+func (m *LabelPair) XXX_Size() int {
+	return xxx_messageInfo_LabelPair.Size(m)
+}
+func (m *LabelPair) XXX_DiscardUnknown() {
+	xxx_messageInfo_LabelPair.DiscardUnknown(m)
+}
+
+var xxx_messageInfo_LabelPair proto.InternalMessageInfo
 
 func (m *LabelPair) GetName() string {
 	if m != nil && m.Name != nil {
@@ -96,13 +110,35 @@ func (m *LabelPair) GetValue() string {
 }
 
 type Gauge struct {
-	Value            *float64 `protobuf:"fixed64,1,opt,name=value" json:"value,omitempty"`
+	Value                *float64 `protobuf:"fixed64,1,opt,name=value" json:"value,omitempty"`
-	XXX_unrecognized []byte   `json:"-"`
+	XXX_NoUnkeyedLiteral struct{} `json:"-"`
+	XXX_unrecognized     []byte   `json:"-"`
+	XXX_sizecache        int32    `json:"-"`
 }
 
 func (m *Gauge) Reset()         { *m = Gauge{} }
 func (m *Gauge) String() string { return proto.CompactTextString(m) }
 func (*Gauge) ProtoMessage()    {}
+func (*Gauge) Descriptor() ([]byte, []int) {
+	return fileDescriptor_metrics_c97c9a2b9560cb8f, []int{1}
+}
+func (m *Gauge) XXX_Unmarshal(b []byte) error {
+	return xxx_messageInfo_Gauge.Unmarshal(m, b)
+}
+func (m *Gauge) XXX_Marshal(b []byte, deterministic bool) ([]byte, error) {
+	return xxx_messageInfo_Gauge.Marshal(b, m, deterministic)
+}
+func (dst *Gauge) XXX_Merge(src proto.Message) {
+	xxx_messageInfo_Gauge.Merge(dst, src)
+}
+func (m *Gauge) XXX_Size() int {
+	return xxx_messageInfo_Gauge.Size(m)
+}
+func (m *Gauge) XXX_DiscardUnknown() {
+	xxx_messageInfo_Gauge.DiscardUnknown(m)
+}
+
+var xxx_messageInfo_Gauge proto.InternalMessageInfo
 
 func (m *Gauge) GetValue() float64 {
 	if m != nil && m.Value != nil {
@@ -112,13 +148,35 @@ func (m *Gauge) GetValue() float64 {
 }
 
 type Counter struct {
-	Value            *float64 `protobuf:"fixed64,1,opt,name=value" json:"value,omitempty"`
+	Value                *float64 `protobuf:"fixed64,1,opt,name=value" json:"value,omitempty"`
-	XXX_unrecognized []byte   `json:"-"`
+	XXX_NoUnkeyedLiteral struct{} `json:"-"`
+	XXX_unrecognized     []byte   `json:"-"`
+	XXX_sizecache        int32    `json:"-"`
 }
 
 func (m *Counter) Reset()         { *m = Counter{} }
 func (m *Counter) String() string { return proto.CompactTextString(m) }
 func (*Counter) ProtoMessage()    {}
+func (*Counter) Descriptor() ([]byte, []int) {
+	return fileDescriptor_metrics_c97c9a2b9560cb8f, []int{2}
+}
+func (m *Counter) XXX_Unmarshal(b []byte) error {
+	return xxx_messageInfo_Counter.Unmarshal(m, b)
+}
+func (m *Counter) XXX_Marshal(b []byte, deterministic bool) ([]byte, error) {
+	return xxx_messageInfo_Counter.Marshal(b, m, deterministic)
+}
+func (dst *Counter) XXX_Merge(src proto.Message) {
+	xxx_messageInfo_Counter.Merge(dst, src)
+}
+func (m *Counter) XXX_Size() int {
+	return xxx_messageInfo_Counter.Size(m)
+}
+func (m *Counter) XXX_DiscardUnknown() {
+	xxx_messageInfo_Counter.DiscardUnknown(m)
+}
+
+var xxx_messageInfo_Counter proto.InternalMessageInfo
 
 func (m *Counter) GetValue() float64 {
 	if m != nil && m.Value != nil {
@@ -128,14 +186,36 @@ func (m *Counter) GetValue() float64 {
 }
 
 type Quantile struct {
-	Quantile         *float64 `protobuf:"fixed64,1,opt,name=quantile" json:"quantile,omitempty"`
+	Quantile             *float64 `protobuf:"fixed64,1,opt,name=quantile" json:"quantile,omitempty"`
-	Value            *float64 `protobuf:"fixed64,2,opt,name=value" json:"value,omitempty"`
+	Value                *float64 `protobuf:"fixed64,2,opt,name=value" json:"value,omitempty"`
-	XXX_unrecognized []byte   `json:"-"`
+	XXX_NoUnkeyedLiteral struct{} `json:"-"`
+	XXX_unrecognized     []byte   `json:"-"`
+	XXX_sizecache        int32    `json:"-"`
 }
 
 func (m *Quantile) Reset()         { *m = Quantile{} }
 func (m *Quantile) String() string { return proto.CompactTextString(m) }
 func (*Quantile) ProtoMessage()    {}
+func (*Quantile) Descriptor() ([]byte, []int) {
+	return fileDescriptor_metrics_c97c9a2b9560cb8f, []int{3}
+}
+func (m *Quantile) XXX_Unmarshal(b []byte) error {
+	return xxx_messageInfo_Quantile.Unmarshal(m, b)
+}
+func (m *Quantile) XXX_Marshal(b []byte, deterministic bool) ([]byte, error) {
+	return xxx_messageInfo_Quantile.Marshal(b, m, deterministic)
+}
+func (dst *Quantile) XXX_Merge(src proto.Message) {
+	xxx_messageInfo_Quantile.Merge(dst, src)
+}
+func (m *Quantile) XXX_Size() int {
+	return xxx_messageInfo_Quantile.Size(m)
+}
+func (m *Quantile) XXX_DiscardUnknown() {
+	xxx_messageInfo_Quantile.DiscardUnknown(m)
+}
+
+var xxx_messageInfo_Quantile proto.InternalMessageInfo
 
 func (m *Quantile) GetQuantile() float64 {
 	if m != nil && m.Quantile != nil {
@@ -152,15 +232,37 @@ func (m *Quantile) GetValue() float64 {
 }
 
 type Summary struct {
-	SampleCount      *uint64     `protobuf:"varint,1,opt,name=sample_count" json:"sample_count,omitempty"`
+	SampleCount          *uint64     `protobuf:"varint,1,opt,name=sample_count,json=sampleCount" json:"sample_count,omitempty"`
-	SampleSum        *float64    `protobuf:"fixed64,2,opt,name=sample_sum" json:"sample_sum,omitempty"`
+	SampleSum            *float64    `protobuf:"fixed64,2,opt,name=sample_sum,json=sampleSum" json:"sample_sum,omitempty"`
-	Quantile         []*Quantile `protobuf:"bytes,3,rep,name=quantile" json:"quantile,omitempty"`
+	Quantile             []*Quantile `protobuf:"bytes,3,rep,name=quantile" json:"quantile,omitempty"`
-	XXX_unrecognized []byte      `json:"-"`
+	XXX_NoUnkeyedLiteral struct{}    `json:"-"`
+	XXX_unrecognized     []byte      `json:"-"`
+	XXX_sizecache        int32       `json:"-"`
 }
 
 func (m *Summary) Reset()         { *m = Summary{} }
 func (m *Summary) String() string { return proto.CompactTextString(m) }
 func (*Summary) ProtoMessage()    {}
+func (*Summary) Descriptor() ([]byte, []int) {
+	return fileDescriptor_metrics_c97c9a2b9560cb8f, []int{4}
+}
+func (m *Summary) XXX_Unmarshal(b []byte) error {
+	return xxx_messageInfo_Summary.Unmarshal(m, b)
+}
+func (m *Summary) XXX_Marshal(b []byte, deterministic bool) ([]byte, error) {
+	return xxx_messageInfo_Summary.Marshal(b, m, deterministic)
+}
+func (dst *Summary) XXX_Merge(src proto.Message) {
+	xxx_messageInfo_Summary.Merge(dst, src)
+}
+func (m *Summary) XXX_Size() int {
+	return xxx_messageInfo_Summary.Size(m)
+}
+func (m *Summary) XXX_DiscardUnknown() {
+	xxx_messageInfo_Summary.DiscardUnknown(m)
+}
+
+var xxx_messageInfo_Summary proto.InternalMessageInfo
 
 func (m *Summary) GetSampleCount() uint64 {
 	if m != nil && m.SampleCount != nil {
@@ -184,13 +286,35 @@ func (m *Summary) GetQuantile() []*Quantile {
 }
 
 type Untyped struct {
-	Value            *float64 `protobuf:"fixed64,1,opt,name=value" json:"value,omitempty"`
+	Value                *float64 `protobuf:"fixed64,1,opt,name=value" json:"value,omitempty"`
-	XXX_unrecognized []byte   `json:"-"`
+	XXX_NoUnkeyedLiteral struct{} `json:"-"`
+	XXX_unrecognized     []byte   `json:"-"`
+	XXX_sizecache        int32    `json:"-"`
 }
 
 func (m *Untyped) Reset()         { *m = Untyped{} }
 func (m *Untyped) String() string { return proto.CompactTextString(m) }
 func (*Untyped) ProtoMessage()    {}
+func (*Untyped) Descriptor() ([]byte, []int) {
+	return fileDescriptor_metrics_c97c9a2b9560cb8f, []int{5}
+}
+func (m *Untyped) XXX_Unmarshal(b []byte) error {
+	return xxx_messageInfo_Untyped.Unmarshal(m, b)
+}
+func (m *Untyped) XXX_Marshal(b []byte, deterministic bool) ([]byte, error) {
+	return xxx_messageInfo_Untyped.Marshal(b, m, deterministic)
+}
+func (dst *Untyped) XXX_Merge(src proto.Message) {
+	xxx_messageInfo_Untyped.Merge(dst, src)
+}
+func (m *Untyped) XXX_Size() int {
+	return xxx_messageInfo_Untyped.Size(m)
+}
+func (m *Untyped) XXX_DiscardUnknown() {
+	xxx_messageInfo_Untyped.DiscardUnknown(m)
+}
+
+var xxx_messageInfo_Untyped proto.InternalMessageInfo
 
 func (m *Untyped) GetValue() float64 {
 	if m != nil && m.Value != nil {
@@ -200,15 +324,37 @@ func (m *Untyped) GetValue() float64 {
 }
 
 type Histogram struct {
-	SampleCount      *uint64   `protobuf:"varint,1,opt,name=sample_count" json:"sample_count,omitempty"`
+	SampleCount          *uint64   `protobuf:"varint,1,opt,name=sample_count,json=sampleCount" json:"sample_count,omitempty"`
-	SampleSum        *float64  `protobuf:"fixed64,2,opt,name=sample_sum" json:"sample_sum,omitempty"`
+	SampleSum            *float64  `protobuf:"fixed64,2,opt,name=sample_sum,json=sampleSum" json:"sample_sum,omitempty"`
-	Bucket           []*Bucket `protobuf:"bytes,3,rep,name=bucket" json:"bucket,omitempty"`
+	Bucket               []*Bucket `protobuf:"bytes,3,rep,name=bucket" json:"bucket,omitempty"`
-	XXX_unrecognized []byte    `json:"-"`
+	XXX_NoUnkeyedLiteral struct{}  `json:"-"`
+	XXX_unrecognized     []byte    `json:"-"`
+	XXX_sizecache        int32     `json:"-"`
 }
 
 func (m *Histogram) Reset()         { *m = Histogram{} }
 func (m *Histogram) String() string { return proto.CompactTextString(m) }
 func (*Histogram) ProtoMessage()    {}
+func (*Histogram) Descriptor() ([]byte, []int) {
+	return fileDescriptor_metrics_c97c9a2b9560cb8f, []int{6}
+}
+func (m *Histogram) XXX_Unmarshal(b []byte) error {
+	return xxx_messageInfo_Histogram.Unmarshal(m, b)
+}
+func (m *Histogram) XXX_Marshal(b []byte, deterministic bool) ([]byte, error) {
+	return xxx_messageInfo_Histogram.Marshal(b, m, deterministic)
+}
+func (dst *Histogram) XXX_Merge(src proto.Message) {
+	xxx_messageInfo_Histogram.Merge(dst, src)
+}
+func (m *Histogram) XXX_Size() int {
+	return xxx_messageInfo_Histogram.Size(m)
+}
+func (m *Histogram) XXX_DiscardUnknown() {
+	xxx_messageInfo_Histogram.DiscardUnknown(m)
+}
+
+var xxx_messageInfo_Histogram proto.InternalMessageInfo
 
 func (m *Histogram) GetSampleCount() uint64 {
 	if m != nil && m.SampleCount != nil {
@@ -232,14 +378,36 @@ func (m *Histogram) GetBucket() []*Bucket {
 }
 
 type Bucket struct {
-	CumulativeCount  *uint64  `protobuf:"varint,1,opt,name=cumulative_count" json:"cumulative_count,omitempty"`
+	CumulativeCount      *uint64  `protobuf:"varint,1,opt,name=cumulative_count,json=cumulativeCount" json:"cumulative_count,omitempty"`
-	UpperBound       *float64 `protobuf:"fixed64,2,opt,name=upper_bound" json:"upper_bound,omitempty"`
+	UpperBound           *float64 `protobuf:"fixed64,2,opt,name=upper_bound,json=upperBound" json:"upper_bound,omitempty"`
-	XXX_unrecognized []byte   `json:"-"`
+	XXX_NoUnkeyedLiteral struct{} `json:"-"`
+	XXX_unrecognized     []byte   `json:"-"`
+	XXX_sizecache        int32    `json:"-"`
 }
 
 func (m *Bucket) Reset()         { *m = Bucket{} }
 func (m *Bucket) String() string { return proto.CompactTextString(m) }
 func (*Bucket) ProtoMessage()    {}
+func (*Bucket) Descriptor() ([]byte, []int) {
+	return fileDescriptor_metrics_c97c9a2b9560cb8f, []int{7}
+}
+func (m *Bucket) XXX_Unmarshal(b []byte) error {
+	return xxx_messageInfo_Bucket.Unmarshal(m, b)
+}
+func (m *Bucket) XXX_Marshal(b []byte, deterministic bool) ([]byte, error) {
+	return xxx_messageInfo_Bucket.Marshal(b, m, deterministic)
+}
+func (dst *Bucket) XXX_Merge(src proto.Message) {
+	xxx_messageInfo_Bucket.Merge(dst, src)
+}
+func (m *Bucket) XXX_Size() int {
+	return xxx_messageInfo_Bucket.Size(m)
+}
+func (m *Bucket) XXX_DiscardUnknown() {
+	xxx_messageInfo_Bucket.DiscardUnknown(m)
+}
+
+var xxx_messageInfo_Bucket proto.InternalMessageInfo
 
 func (m *Bucket) GetCumulativeCount() uint64 {
 	if m != nil && m.CumulativeCount != nil {
@@ -256,19 +424,41 @@ func (m *Bucket) GetUpperBound() float64 {
 }
 
 type Metric struct {
-	Label            []*LabelPair `protobuf:"bytes,1,rep,name=label" json:"label,omitempty"`
+	Label                []*LabelPair `protobuf:"bytes,1,rep,name=label" json:"label,omitempty"`
-	Gauge            *Gauge       `protobuf:"bytes,2,opt,name=gauge" json:"gauge,omitempty"`
+	Gauge                *Gauge       `protobuf:"bytes,2,opt,name=gauge" json:"gauge,omitempty"`
-	Counter          *Counter     `protobuf:"bytes,3,opt,name=counter" json:"counter,omitempty"`
+	Counter              *Counter     `protobuf:"bytes,3,opt,name=counter" json:"counter,omitempty"`
-	Summary          *Summary     `protobuf:"bytes,4,opt,name=summary" json:"summary,omitempty"`
+	Summary              *Summary     `protobuf:"bytes,4,opt,name=summary" json:"summary,omitempty"`
-	Untyped          *Untyped     `protobuf:"bytes,5,opt,name=untyped" json:"untyped,omitempty"`
+	Untyped              *Untyped     `protobuf:"bytes,5,opt,name=untyped" json:"untyped,omitempty"`
-	Histogram        *Histogram   `protobuf:"bytes,7,opt,name=histogram" json:"histogram,omitempty"`
+	Histogram            *Histogram   `protobuf:"bytes,7,opt,name=histogram" json:"histogram,omitempty"`
-	TimestampMs      *int64       `protobuf:"varint,6,opt,name=timestamp_ms" json:"timestamp_ms,omitempty"`
+	TimestampMs          *int64       `protobuf:"varint,6,opt,name=timestamp_ms,json=timestampMs" json:"timestamp_ms,omitempty"`
-	XXX_unrecognized []byte       `json:"-"`
+	XXX_NoUnkeyedLiteral struct{}     `json:"-"`
+	XXX_unrecognized     []byte       `json:"-"`
+	XXX_sizecache        int32        `json:"-"`
 }
 
 func (m *Metric) Reset()         { *m = Metric{} }
 func (m *Metric) String() string { return proto.CompactTextString(m) }
 func (*Metric) ProtoMessage()    {}
+func (*Metric) Descriptor() ([]byte, []int) {
+	return fileDescriptor_metrics_c97c9a2b9560cb8f, []int{8}
+}
+func (m *Metric) XXX_Unmarshal(b []byte) error {
+	return xxx_messageInfo_Metric.Unmarshal(m, b)
+}
+func (m *Metric) XXX_Marshal(b []byte, deterministic bool) ([]byte, error) {
+	return xxx_messageInfo_Metric.Marshal(b, m, deterministic)
+}
+func (dst *Metric) XXX_Merge(src proto.Message) {
+	xxx_messageInfo_Metric.Merge(dst, src)
+}
+func (m *Metric) XXX_Size() int {
+	return xxx_messageInfo_Metric.Size(m)
+}
+func (m *Metric) XXX_DiscardUnknown() {
+	xxx_messageInfo_Metric.DiscardUnknown(m)
+}
+
+var xxx_messageInfo_Metric proto.InternalMessageInfo
 
 func (m *Metric) GetLabel() []*LabelPair {
 	if m != nil {
@@ -320,16 +510,38 @@ func (m *Metric) GetTimestampMs() int64 {
 }
 
 type MetricFamily struct {
-	Name             *string     `protobuf:"bytes,1,opt,name=name" json:"name,omitempty"`
+	Name                 *string     `protobuf:"bytes,1,opt,name=name" json:"name,omitempty"`
-	Help             *string     `protobuf:"bytes,2,opt,name=help" json:"help,omitempty"`
+	Help                 *string     `protobuf:"bytes,2,opt,name=help" json:"help,omitempty"`
-	Type             *MetricType `protobuf:"varint,3,opt,name=type,enum=io.prometheus.client.MetricType" json:"type,omitempty"`
+	Type                 *MetricType `protobuf:"varint,3,opt,name=type,enum=io.prometheus.client.MetricType" json:"type,omitempty"`
-	Metric           []*Metric   `protobuf:"bytes,4,rep,name=metric" json:"metric,omitempty"`
+	Metric               []*Metric   `protobuf:"bytes,4,rep,name=metric" json:"metric,omitempty"`
-	XXX_unrecognized []byte      `json:"-"`
+	XXX_NoUnkeyedLiteral struct{}    `json:"-"`
+	XXX_unrecognized     []byte      `json:"-"`
+	XXX_sizecache        int32       `json:"-"`
 }
 
 func (m *MetricFamily) Reset()         { *m = MetricFamily{} }
 func (m *MetricFamily) String() string { return proto.CompactTextString(m) }
 func (*MetricFamily) ProtoMessage()    {}
+func (*MetricFamily) Descriptor() ([]byte, []int) {
+	return fileDescriptor_metrics_c97c9a2b9560cb8f, []int{9}
+}
+func (m *MetricFamily) XXX_Unmarshal(b []byte) error {
+	return xxx_messageInfo_MetricFamily.Unmarshal(m, b)
+}
+func (m *MetricFamily) XXX_Marshal(b []byte, deterministic bool) ([]byte, error) {
+	return xxx_messageInfo_MetricFamily.Marshal(b, m, deterministic)
+}
+func (dst *MetricFamily) XXX_Merge(src proto.Message) {
+	xxx_messageInfo_MetricFamily.Merge(dst, src)
+}
+func (m *MetricFamily) XXX_Size() int {
+	return xxx_messageInfo_MetricFamily.Size(m)
+}
+func (m *MetricFamily) XXX_DiscardUnknown() {
+	xxx_messageInfo_MetricFamily.DiscardUnknown(m)
+}
+
+var xxx_messageInfo_MetricFamily proto.InternalMessageInfo
 
 func (m *MetricFamily) GetName() string {
 	if m != nil && m.Name != nil {
@@ -360,5 +572,58 @@ func (m *MetricFamily) GetMetric() []*Metric {
 }
 
 func init() {
+	proto.RegisterType((*LabelPair)(nil), "io.prometheus.client.LabelPair")
+	proto.RegisterType((*Gauge)(nil), "io.prometheus.client.Gauge")
+	proto.RegisterType((*Counter)(nil), "io.prometheus.client.Counter")
+	proto.RegisterType((*Quantile)(nil), "io.prometheus.client.Quantile")
+	proto.RegisterType((*Summary)(nil), "io.prometheus.client.Summary")
+	proto.RegisterType((*Untyped)(nil), "io.prometheus.client.Untyped")
+	proto.RegisterType((*Histogram)(nil), "io.prometheus.client.Histogram")
+	proto.RegisterType((*Bucket)(nil), "io.prometheus.client.Bucket")
+	proto.RegisterType((*Metric)(nil), "io.prometheus.client.Metric")
+	proto.RegisterType((*MetricFamily)(nil), "io.prometheus.client.MetricFamily")
 	proto.RegisterEnum("io.prometheus.client.MetricType", MetricType_name, MetricType_value)
 }
+
+func init() { proto.RegisterFile("metrics.proto", fileDescriptor_metrics_c97c9a2b9560cb8f) }
+
+var fileDescriptor_metrics_c97c9a2b9560cb8f = []byte{
+	// 591 bytes of a gzipped FileDescriptorProto
+	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xff, 0xac, 0x54, 0x4f, 0x4f, 0xdb, 0x4e,
+	0x14, 0xfc, 0x99, 0xd8, 0x09, 0x7e, 0x86, 0x5f, 0xad, 0x15, 0x07, 0xab, 0x2d, 0x25, 0xcd, 0x89,
+	0xf6, 0x10, 0x54, 0x04, 0xaa, 0x44, 0xdb, 0x03, 0x50, 0x1a, 0x2a, 0xd5, 0x40, 0x37, 0xc9, 0x81,
+	0x5e, 0xac, 0x8d, 0x59, 0x25, 0x56, 0xbd, 0xb6, 0x6b, 0xef, 0x22, 0xe5, 0xdc, 0x43, 0xbf, 0x47,
+	0xbf, 0x68, 0xab, 0xfd, 0xe3, 0x18, 0x24, 0xc3, 0xa9, 0xb7, 0xb7, 0xf3, 0x66, 0xde, 0x8e, 0x77,
+	0xc7, 0x0b, 0x9b, 0x8c, 0xf2, 0x32, 0x89, 0xab, 0x61, 0x51, 0xe6, 0x3c, 0x47, 0x5b, 0x49, 0x2e,
+	0x2b, 0x46, 0xf9, 0x82, 0x8a, 0x6a, 0x18, 0xa7, 0x09, 0xcd, 0xf8, 0xe0, 0x10, 0xdc, 0x2f, 0x64,
+	0x46, 0xd3, 0x2b, 0x92, 0x94, 0x08, 0x81, 0x9d, 0x11, 0x46, 0x03, 0xab, 0x6f, 0xed, 0xba, 0x58,
+	0xd5, 0x68, 0x0b, 0x9c, 0x5b, 0x92, 0x0a, 0x1a, 0xac, 0x29, 0x50, 0x2f, 0x06, 0xdb, 0xe0, 0x8c,
+	0x88, 0x98, 0xdf, 0x69, 0x4b, 0x8d, 0x55, 0xb7, 0x77, 0xa0, 0x77, 0x9a, 0x8b, 0x8c, 0xd3, 0xf2,
+	0x01, 0xc2, 0x7b, 0x58, 0xff, 0x2a, 0x48, 0xc6, 0x93, 0x94, 0xa2, 0xa7, 0xb0, 0xfe, 0xc3, 0xd4,
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+	0xf3, 0x76, 0xab, 0x27, 0x8a, 0x83, 0x0d, 0x77, 0x30, 0x81, 0xae, 0x46, 0xd0, 0x2b, 0xf0, 0x63,
+	0xc1, 0x44, 0x4a, 0x78, 0x72, 0x7b, 0xdf, 0xc5, 0x93, 0x06, 0xd7, 0x4e, 0x76, 0xc0, 0x13, 0x45,
+	0x41, 0xcb, 0x68, 0x96, 0x8b, 0xec, 0xc6, 0x58, 0x01, 0x05, 0x9d, 0x48, 0x64, 0xf0, 0x67, 0x0d,
+	0xba, 0xa1, 0xca, 0x18, 0x3a, 0x04, 0x27, 0x95, 0x31, 0x0a, 0x2c, 0xe5, 0x6a, 0xa7, 0xdd, 0xd5,
+	0x2a, 0x69, 0x58, 0xb3, 0xd1, 0x1b, 0x70, 0xe6, 0x32, 0x46, 0x6a, 0xb8, 0xb7, 0xff, 0xac, 0x5d,
+	0xa6, 0x92, 0x86, 0x35, 0x13, 0xbd, 0x85, 0x5e, 0xac, 0xa3, 0x15, 0x74, 0x94, 0x68, 0xbb, 0x5d,
+	0x64, 0xf2, 0x87, 0x6b, 0xb6, 0x14, 0x56, 0x3a, 0x33, 0x81, 0xfd, 0x98, 0xd0, 0x04, 0x0b, 0xd7,
+	0x6c, 0x29, 0x14, 0xfa, 0x8e, 0x03, 0xe7, 0x31, 0xa1, 0x09, 0x02, 0xae, 0xd9, 0xe8, 0x03, 0xb8,
+	0x8b, 0xfa, 0xea, 0x83, 0x9e, 0x92, 0x3e, 0x70, 0x30, 0xab, 0x84, 0xe0, 0x46, 0x21, 0xc3, 0xc2,
+	0x13, 0x46, 0x2b, 0x4e, 0x58, 0x11, 0xb1, 0x2a, 0xe8, 0xf6, 0xad, 0xdd, 0x0e, 0xf6, 0x56, 0x58,
+	0x58, 0x0d, 0x7e, 0x5b, 0xb0, 0xa1, 0x6f, 0xe0, 0x13, 0x61, 0x49, 0xba, 0x6c, 0xfd, 0x83, 0x11,
+	0xd8, 0x0b, 0x9a, 0x16, 0xe6, 0x07, 0x56, 0x35, 0x3a, 0x00, 0x5b, 0x7a, 0x54, 0x47, 0xf8, 0xff,
+	0x7e, 0xbf, 0xdd, 0x95, 0x9e, 0x3c, 0x59, 0x16, 0x14, 0x2b, 0xb6, 0x0c, 0x9f, 0x7e, 0x53, 0x02,
+	0xfb, 0xb1, 0xf0, 0x69, 0x1d, 0x36, 0xdc, 0xd7, 0x21, 0x40, 0x33, 0x09, 0x79, 0xd0, 0x3b, 0xbd,
+	0x9c, 0x5e, 0x4c, 0xce, 0xb0, 0xff, 0x1f, 0x72, 0xc1, 0x19, 0x1d, 0x4f, 0x47, 0x67, 0xbe, 0x25,
+	0xf1, 0xf1, 0x34, 0x0c, 0x8f, 0xf1, 0xb5, 0xbf, 0x26, 0x17, 0xd3, 0x8b, 0xc9, 0xf5, 0xd5, 0xd9,
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+	0x18, 0x5a, 0x5f, 0xb2, 0x6f, 0x47, 0xf3, 0x84, 0x2f, 0xc4, 0x6c, 0x18, 0xe7, 0x6c, 0xaf, 0xe9,
+	0xee, 0xe9, 0x6e, 0xc4, 0xf2, 0x1b, 0x9a, 0xee, 0xcd, 0xf3, 0x77, 0x49, 0x1e, 0x35, 0xdd, 0x48,
+	0x77, 0xff, 0x06, 0x00, 0x00, 0xff, 0xff, 0x45, 0x21, 0x7f, 0x64, 0x2b, 0x05, 0x00, 0x00,
+}

vendor/vendor.json

@@ -757,34 +757,40 @@
 			"revisionTime": "2016-06-15T09:26:46Z"
 		},
 		{
-			"checksumSHA1": "4VppKBbzCSmoFfQxGNUm0TYiFCA=",
+			"checksumSHA1": "qeRNcE15+58PvlfKwBA2n96Qa5I=",
 			"path": "github.com/prometheus/client_golang/api",
-			"revision": "faf4ec335fe01ae5a6a0eaa34a5a9333bfbd1a30",
+			"revision": "e637cec7d9c8990247098639ebc6d43dd34ddd49",
-			"revisionTime": "2018-06-07T12:36:07Z"
+			"revisionTime": "2018-09-17T10:21:22Z"
 		},
 		{
 			"checksumSHA1": "83pGB3cRG5uqx9O5d+7MCB+TFT4=",
 			"path": "github.com/prometheus/client_golang/api/prometheus/v1",
-			"revision": "faf4ec335fe01ae5a6a0eaa34a5a9333bfbd1a30",
+			"revision": "e637cec7d9c8990247098639ebc6d43dd34ddd49",
-			"revisionTime": "2018-06-07T12:36:07Z"
+			"revisionTime": "2018-09-17T10:21:22Z"
 		},
 		{
-			"checksumSHA1": "WVgL9pNO2RZCCcaXfSYSNEPgtCo=",
+			"checksumSHA1": "lLvg5TpUtFbkyAoh+aI5T/nnpWw=",
 			"path": "github.com/prometheus/client_golang/prometheus",
-			"revision": "faf4ec335fe01ae5a6a0eaa34a5a9333bfbd1a30",
+			"revision": "e637cec7d9c8990247098639ebc6d43dd34ddd49",
-			"revisionTime": "2018-06-07T12:36:07Z"
+			"revisionTime": "2018-09-17T10:21:22Z"
 		},
 		{
-			"checksumSHA1": "MYqKV5uVTfCxP9zBug7naBQ1vr8=",
+			"checksumSHA1": "UBqhkyjCz47+S19MVTigxJ2VjVQ=",
+			"path": "github.com/prometheus/client_golang/prometheus/internal",
+			"revision": "e637cec7d9c8990247098639ebc6d43dd34ddd49",
+			"revisionTime": "2018-09-17T10:21:22Z"
+		},
+		{
+			"checksumSHA1": "d5BiEvD8MrgpWQ6PQJUvawJsMak=",
 			"path": "github.com/prometheus/client_golang/prometheus/promhttp",
-			"revision": "faf4ec335fe01ae5a6a0eaa34a5a9333bfbd1a30",
+			"revision": "e637cec7d9c8990247098639ebc6d43dd34ddd49",
-			"revisionTime": "2018-06-07T12:36:07Z"
+			"revisionTime": "2018-09-17T10:21:22Z"
 		},
 		{
-			"checksumSHA1": "DvwvOlPNAgRntBzt3b3OSRMS2N4=",
+			"checksumSHA1": "V8xkqgmP66sq2ZW4QO5wi9a4oZE=",
 			"path": "github.com/prometheus/client_model/go",
-			"revision": "fa8ad6fec33561be4280a8f0514318c79d7f6cb6",
+			"revision": "5c3871d89910bfb32f5fcab2aa4b9ec68e65a99f",
-			"revisionTime": "2015-02-12T10:17:44Z"
+			"revisionTime": "2018-07-12T10:51:10Z"
 		},
 		{
 			"checksumSHA1": "cxLURB7wEFsMAZ6fi5Ptfdrwdc8=",