rollback prometheus/client_golang to 0.7.0

vendor/github.com/prometheus/client_golang/NOTICE

@@ -7,6 +7,11 @@ SoundCloud Ltd. (http://soundcloud.com/).
 
 The following components are included in this product:
 
+goautoneg
+http://bitbucket.org/ww/goautoneg
+Copyright 2011, Open Knowledge Foundation Ltd.
+See README.txt for license details.
+
 perks - a fork of https://github.com/bmizerany/perks
 https://github.com/beorn7/perks
 Copyright 2013-2015 Blake Mizerany, Björn Rabenstein

vendor/github.com/prometheus/client_golang/model/fingerprinting.go

@@ -0,0 +1,110 @@
+// Copyright 2013 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 model
+
+import (
+	"fmt"
+	"strconv"
+)
+
+// Fingerprint provides a hash-capable representation of a Metric.
+// For our purposes, FNV-1A 64-bit is used.
+type Fingerprint uint64
+
+func (f Fingerprint) String() string {
+	return fmt.Sprintf("%016x", uint64(f))
+}
+
+// Less implements sort.Interface.
+func (f Fingerprint) Less(o Fingerprint) bool {
+	return f < o
+}
+
+// Equal implements sort.Interface.
+func (f Fingerprint) Equal(o Fingerprint) bool {
+	return f == o
+}
+
+// LoadFromString transforms a string representation into a Fingerprint.
+func (f *Fingerprint) LoadFromString(s string) error {
+	num, err := strconv.ParseUint(s, 16, 64)
+	if err != nil {
+		return err
+	}
+	*f = Fingerprint(num)
+	return nil
+}
+
+// Fingerprints represents a collection of Fingerprint subject to a given
+// natural sorting scheme. It implements sort.Interface.
+type Fingerprints []Fingerprint
+
+// Len implements sort.Interface.
+func (f Fingerprints) Len() int {
+	return len(f)
+}
+
+// Less implements sort.Interface.
+func (f Fingerprints) Less(i, j int) bool {
+	return f[i] < f[j]
+}
+
+// Swap implements sort.Interface.
+func (f Fingerprints) Swap(i, j int) {
+	f[i], f[j] = f[j], f[i]
+}
+
+// FingerprintSet is a set of Fingerprints.
+type FingerprintSet map[Fingerprint]struct{}
+
+// Equal returns true if both sets contain the same elements (and not more).
+func (s FingerprintSet) Equal(o FingerprintSet) bool {
+	if len(s) != len(o) {
+		return false
+	}
+
+	for k := range s {
+		if _, ok := o[k]; !ok {
+			return false
+		}
+	}
+
+	return true
+}
+
+// Intersection returns the elements contained in both sets.
+func (s FingerprintSet) Intersection(o FingerprintSet) FingerprintSet {
+	myLength, otherLength := len(s), len(o)
+	if myLength == 0 || otherLength == 0 {
+		return FingerprintSet{}
+	}
+
+	subSet := s
+	superSet := o
+
+	if otherLength < myLength {
+		subSet = o
+		superSet = s
+	}
+
+	out := FingerprintSet{}
+
+	for k := range subSet {
+		if _, ok := superSet[k]; ok {
+			out[k] = struct{}{}
+		}
+	}
+
+	return out
+}

vendor/github.com/prometheus/client_golang/model/labelname.go

@@ -0,0 +1,119 @@
+// Copyright 2013 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 model
+
+import (
+	"encoding/json"
+	"fmt"
+	"regexp"
+	"strings"
+)
+
+const (
+	// ExportedLabelPrefix is the prefix to prepend to the label names present in
+	// exported metrics if a label of the same name is added by the server.
+	ExportedLabelPrefix LabelName = "exported_"
+
+	// MetricNameLabel is the label name indicating the metric name of a
+	// timeseries.
+	MetricNameLabel LabelName = "__name__"
+
+	// AddressLabel is the name of the label that holds the address of
+	// a scrape target.
+	AddressLabel LabelName = "__address__"
+
+	// MetricsPathLabel is the name of the label that holds the path on which to
+	// scrape a target.
+	MetricsPathLabel LabelName = "__metrics_path__"
+
+	// ReservedLabelPrefix is a prefix which is not legal in user-supplied
+	// label names.
+	ReservedLabelPrefix = "__"
+
+	// MetaLabelPrefix is a prefix for labels that provide meta information.
+	// Labels with this prefix are used for intermediate label processing and
+	// will not be attached to time series.
+	MetaLabelPrefix = "__meta_"
+
+	// JobLabel is the label name indicating the job from which a timeseries
+	// was scraped.
+	JobLabel LabelName = "job"
+
+	// InstanceLabel is the label name used for the instance label.
+	InstanceLabel LabelName = "instance"
+
+	// BucketLabel is used for the label that defines the upper bound of a
+	// bucket of a histogram ("le" -> "less or equal").
+	BucketLabel = "le"
+
+	// QuantileLabel is used for the label that defines the quantile in a
+	// summary.
+	QuantileLabel = "quantile"
+)
+
+// LabelNameRE is a regular expression matching valid label names.
+var LabelNameRE = regexp.MustCompile("^[a-zA-Z_][a-zA-Z0-9_]*$")
+
+// A LabelName is a key for a LabelSet or Metric.  It has a value associated
+// therewith.
+type LabelName string
+
+// UnmarshalYAML implements the yaml.Unmarshaler interface.
+func (ln *LabelName) UnmarshalYAML(unmarshal func(interface{}) error) error {
+	var s string
+	if err := unmarshal(&s); err != nil {
+		return err
+	}
+	if !LabelNameRE.MatchString(s) {
+		return fmt.Errorf("%q is not a valid label name", s)
+	}
+	*ln = LabelName(s)
+	return nil
+}
+
+// UnmarshalJSON implements the json.Unmarshaler interface.
+func (ln *LabelName) UnmarshalJSON(b []byte) error {
+	var s string
+	if err := json.Unmarshal(b, &s); err != nil {
+		return err
+	}
+	if !LabelNameRE.MatchString(s) {
+		return fmt.Errorf("%q is not a valid label name", s)
+	}
+	*ln = LabelName(s)
+	return nil
+}
+
+// LabelNames is a sortable LabelName slice. In implements sort.Interface.
+type LabelNames []LabelName
+
+func (l LabelNames) Len() int {
+	return len(l)
+}
+
+func (l LabelNames) Less(i, j int) bool {
+	return l[i] < l[j]
+}
+
+func (l LabelNames) Swap(i, j int) {
+	l[i], l[j] = l[j], l[i]
+}
+
+func (l LabelNames) String() string {
+	labelStrings := make([]string, 0, len(l))
+	for _, label := range l {
+		labelStrings = append(labelStrings, string(label))
+	}
+	return strings.Join(labelStrings, ", ")
+}

vendor/github.com/prometheus/client_golang/model/labelset.go

@@ -0,0 +1,83 @@
+// Copyright 2013 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 model
+
+import (
+	"encoding/json"
+	"fmt"
+	"sort"
+	"strings"
+)
+
+// A LabelSet is a collection of LabelName and LabelValue pairs.  The LabelSet
+// may be fully-qualified down to the point where it may resolve to a single
+// Metric in the data store or not.  All operations that occur within the realm
+// of a LabelSet can emit a vector of Metric entities to which the LabelSet may
+// match.
+type LabelSet map[LabelName]LabelValue
+
+// Merge is a helper function to non-destructively merge two label sets.
+func (l LabelSet) Merge(other LabelSet) LabelSet {
+	result := make(LabelSet, len(l))
+
+	for k, v := range l {
+		result[k] = v
+	}
+
+	for k, v := range other {
+		result[k] = v
+	}
+
+	return result
+}
+
+func (l LabelSet) String() string {
+	labelStrings := make([]string, 0, len(l))
+	for label, value := range l {
+		labelStrings = append(labelStrings, fmt.Sprintf("%s=%q", label, value))
+	}
+
+	switch len(labelStrings) {
+	case 0:
+		return ""
+	default:
+		sort.Strings(labelStrings)
+		return fmt.Sprintf("{%s}", strings.Join(labelStrings, ", "))
+	}
+}
+
+// MergeFromMetric merges Metric into this LabelSet.
+func (l LabelSet) MergeFromMetric(m Metric) {
+	for k, v := range m {
+		l[k] = v
+	}
+}
+
+// UnmarshalJSON implements the json.Unmarshaler interface.
+func (l *LabelSet) UnmarshalJSON(b []byte) error {
+	var m map[LabelName]LabelValue
+	if err := json.Unmarshal(b, &m); err != nil {
+		return err
+	}
+	// encoding/json only unmarshals maps of the form map[string]T. It treats
+	// LabelName as a string and does not call its UnmarshalJSON method.
+	// Thus, we have to replicate the behavior here.
+	for ln := range m {
+		if !LabelNameRE.MatchString(string(ln)) {
+			return fmt.Errorf("%q is not a valid label name", ln)
+		}
+	}
+	*l = LabelSet(m)
+	return nil
+}

vendor/github.com/prometheus/client_golang/model/labelvalue.go

@@ -0,0 +1,36 @@
+// Copyright 2013 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 model
+
+import (
+	"sort"
+)
+
+// A LabelValue is an associated value for a LabelName.
+type LabelValue string
+
+// LabelValues is a sortable LabelValue slice. It implements sort.Interface.
+type LabelValues []LabelValue
+
+func (l LabelValues) Len() int {
+	return len(l)
+}
+
+func (l LabelValues) Less(i, j int) bool {
+	return sort.StringsAreSorted([]string{string(l[i]), string(l[j])})
+}
+
+func (l LabelValues) Swap(i, j int) {
+	l[i], l[j] = l[j], l[i]
+}

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

@@ -0,0 +1,192 @@
+// Copyright 2013 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 model
+
+import (
+	"encoding/json"
+	"fmt"
+	"sort"
+	"strings"
+)
+
+var separator = []byte{0}
+
+// A Metric is similar to a LabelSet, but the key difference is that a Metric is
+// a singleton and refers to one and only one stream of samples.
+type Metric map[LabelName]LabelValue
+
+// Equal compares the metrics.
+func (m Metric) Equal(o Metric) bool {
+	if len(m) != len(o) {
+		return false
+	}
+	for ln, lv := range m {
+		olv, ok := o[ln]
+		if !ok {
+			return false
+		}
+		if olv != lv {
+			return false
+		}
+	}
+	return true
+}
+
+// Before compares the metrics, using the following criteria:
+//
+// If m has fewer labels than o, it is before o. If it has more, it is not.
+//
+// If the number of labels is the same, the superset of all label names is
+// sorted alphanumerically. The first differing label pair found in that order
+// determines the outcome: If the label does not exist at all in m, then m is
+// before o, and vice versa. Otherwise the label value is compared
+// alphanumerically.
+//
+// If m and o are equal, the method returns false.
+func (m Metric) Before(o Metric) bool {
+	if len(m) < len(o) {
+		return true
+	}
+	if len(m) > len(o) {
+		return false
+	}
+
+	lns := make(LabelNames, 0, len(m)+len(o))
+	for ln := range m {
+		lns = append(lns, ln)
+	}
+	for ln := range o {
+		lns = append(lns, ln)
+	}
+	// It's probably not worth it to de-dup lns.
+	sort.Sort(lns)
+	for _, ln := range lns {
+		mlv, ok := m[ln]
+		if !ok {
+			return true
+		}
+		olv, ok := o[ln]
+		if !ok {
+			return false
+		}
+		if mlv < olv {
+			return true
+		}
+		if mlv > olv {
+			return false
+		}
+	}
+	return false
+}
+
+// String implements Stringer.
+func (m Metric) String() string {
+	metricName, hasName := m[MetricNameLabel]
+	numLabels := len(m) - 1
+	if !hasName {
+		numLabels = len(m)
+	}
+	labelStrings := make([]string, 0, numLabels)
+	for label, value := range m {
+		if label != MetricNameLabel {
+			labelStrings = append(labelStrings, fmt.Sprintf("%s=%q", label, value))
+		}
+	}
+
+	switch numLabels {
+	case 0:
+		if hasName {
+			return string(metricName)
+		}
+		return "{}"
+	default:
+		sort.Strings(labelStrings)
+		return fmt.Sprintf("%s{%s}", metricName, strings.Join(labelStrings, ", "))
+	}
+}
+
+// Fingerprint returns a Metric's Fingerprint.
+func (m Metric) Fingerprint() Fingerprint {
+	return metricToFingerprint(m)
+}
+
+// FastFingerprint returns a Metric's Fingerprint calculated by a faster hashing
+// algorithm, which is, however, more susceptible to hash collisions.
+func (m Metric) FastFingerprint() Fingerprint {
+	return metricToFastFingerprint(m)
+}
+
+// Clone returns a copy of the Metric.
+func (m Metric) Clone() Metric {
+	clone := Metric{}
+	for k, v := range m {
+		clone[k] = v
+	}
+	return clone
+}
+
+// MergeFromLabelSet merges a label set into this Metric, prefixing a collision
+// prefix to the label names merged from the label set where required.
+func (m Metric) MergeFromLabelSet(labels LabelSet, collisionPrefix LabelName) {
+	for k, v := range labels {
+		if collisionPrefix != "" {
+			for {
+				if _, exists := m[k]; !exists {
+					break
+				}
+				k = collisionPrefix + k
+			}
+		}
+
+		m[k] = v
+	}
+}
+
+// COWMetric wraps a Metric to enable copy-on-write access patterns.
+type COWMetric struct {
+	Copied bool
+	Metric Metric
+}
+
+// Set sets a label name in the wrapped Metric to a given value and copies the
+// Metric initially, if it is not already a copy.
+func (m *COWMetric) Set(ln LabelName, lv LabelValue) {
+	m.doCOW()
+	m.Metric[ln] = lv
+}
+
+// Delete deletes a given label name from the wrapped Metric and copies the
+// Metric initially, if it is not already a copy.
+func (m *COWMetric) Delete(ln LabelName) {
+	m.doCOW()
+	delete(m.Metric, ln)
+}
+
+// doCOW copies the underlying Metric if it is not already a copy.
+func (m *COWMetric) doCOW() {
+	if !m.Copied {
+		m.Metric = m.Metric.Clone()
+		m.Copied = true
+	}
+}
+
+// String implements fmt.Stringer.
+func (m COWMetric) String() string {
+	return m.Metric.String()
+}
+
+// MarshalJSON implements json.Marshaler.
+func (m COWMetric) MarshalJSON() ([]byte, error) {
+	return json.Marshal(m.Metric)
+}

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

@@ -0,0 +1,15 @@
+// Copyright 2013 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 model contains core representation of Prometheus client primitives.
+package model

vendor/github.com/prometheus/client_golang/model/sample.go

@@ -0,0 +1,79 @@
+// Copyright 2013 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 model
+
+// Sample is a sample value with a timestamp and a metric.
+type Sample struct {
+	Metric    Metric
+	Value     SampleValue
+	Timestamp Timestamp
+}
+
+// Equal compares first the metrics, then the timestamp, then the value.
+func (s *Sample) Equal(o *Sample) bool {
+	if s == o {
+		return true
+	}
+
+	if !s.Metric.Equal(o.Metric) {
+		return false
+	}
+	if !s.Timestamp.Equal(o.Timestamp) {
+		return false
+	}
+	if !s.Value.Equal(o.Value) {
+		return false
+	}
+
+	return true
+}
+
+// Samples is a sortable Sample slice. It implements sort.Interface.
+type Samples []*Sample
+
+func (s Samples) Len() int {
+	return len(s)
+}
+
+// Less compares first the metrics, then the timestamp.
+func (s Samples) Less(i, j int) bool {
+	switch {
+	case s[i].Metric.Before(s[j].Metric):
+		return true
+	case s[j].Metric.Before(s[i].Metric):
+		return false
+	case s[i].Timestamp.Before(s[j].Timestamp):
+		return true
+	default:
+		return false
+	}
+}
+
+func (s Samples) Swap(i, j int) {
+	s[i], s[j] = s[j], s[i]
+}
+
+// Equal compares two sets of samples and returns true if they are equal.
+func (s Samples) Equal(o Samples) bool {
+	if len(s) != len(o) {
+		return false
+	}
+
+	for i, sample := range s {
+		if !sample.Equal(o[i]) {
+			return false
+		}
+	}
+	return true
+}

vendor/github.com/prometheus/client_golang/model/samplevalue.go

@@ -0,0 +1,37 @@
+// Copyright 2013 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 model
+
+import (
+	"fmt"
+	"strconv"
+)
+
+// A SampleValue is a representation of a value for a given sample at a given
+// time.
+type SampleValue float64
+
+// Equal does a straight v==o.
+func (v SampleValue) Equal(o SampleValue) bool {
+	return v == o
+}
+
+// MarshalJSON implements json.Marshaler.
+func (v SampleValue) MarshalJSON() ([]byte, error) {
+	return []byte(fmt.Sprintf(`"%s"`, v)), nil
+}
+
+func (v SampleValue) String() string {
+	return strconv.FormatFloat(float64(v), 'f', -1, 64)
+}

vendor/github.com/prometheus/client_golang/model/signature.go

@@ -0,0 +1,190 @@
+// Copyright 2014 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 model
+
+import (
+	"bytes"
+	"hash"
+	"hash/fnv"
+	"sort"
+	"sync"
+)
+
+// SeparatorByte is a byte that cannot occur in valid UTF-8 sequences and is
+// used to separate label names, label values, and other strings from each other
+// when calculating their combined hash value (aka signature aka fingerprint).
+const SeparatorByte byte = 255
+
+var (
+	// cache the signature of an empty label set.
+	emptyLabelSignature = fnv.New64a().Sum64()
+
+	hashAndBufPool sync.Pool
+)
+
+type hashAndBuf struct {
+	h hash.Hash64
+	b bytes.Buffer
+}
+
+func getHashAndBuf() *hashAndBuf {
+	hb := hashAndBufPool.Get()
+	if hb == nil {
+		return &hashAndBuf{h: fnv.New64a()}
+	}
+	return hb.(*hashAndBuf)
+}
+
+func putHashAndBuf(hb *hashAndBuf) {
+	hb.h.Reset()
+	hb.b.Reset()
+	hashAndBufPool.Put(hb)
+}
+
+// LabelsToSignature returns a quasi-unique signature (i.e., fingerprint) for a
+// given label set. (Collisions are possible but unlikely if the number of label
+// sets the function is applied to is small.)
+func LabelsToSignature(labels map[string]string) uint64 {
+	if len(labels) == 0 {
+		return emptyLabelSignature
+	}
+
+	labelNames := make([]string, 0, len(labels))
+	for labelName := range labels {
+		labelNames = append(labelNames, labelName)
+	}
+	sort.Strings(labelNames)
+
+	hb := getHashAndBuf()
+	defer putHashAndBuf(hb)
+
+	for _, labelName := range labelNames {
+		hb.b.WriteString(labelName)
+		hb.b.WriteByte(SeparatorByte)
+		hb.b.WriteString(labels[labelName])
+		hb.b.WriteByte(SeparatorByte)
+		hb.h.Write(hb.b.Bytes())
+		hb.b.Reset()
+	}
+	return hb.h.Sum64()
+}
+
+// metricToFingerprint works exactly as LabelsToSignature but takes a Metric as
+// parameter (rather than a label map) and returns a Fingerprint.
+func metricToFingerprint(m Metric) Fingerprint {
+	if len(m) == 0 {
+		return Fingerprint(emptyLabelSignature)
+	}
+
+	labelNames := make(LabelNames, 0, len(m))
+	for labelName := range m {
+		labelNames = append(labelNames, labelName)
+	}
+	sort.Sort(labelNames)
+
+	hb := getHashAndBuf()
+	defer putHashAndBuf(hb)
+
+	for _, labelName := range labelNames {
+		hb.b.WriteString(string(labelName))
+		hb.b.WriteByte(SeparatorByte)
+		hb.b.WriteString(string(m[labelName]))
+		hb.b.WriteByte(SeparatorByte)
+		hb.h.Write(hb.b.Bytes())
+		hb.b.Reset()
+	}
+	return Fingerprint(hb.h.Sum64())
+}
+
+// metricToFastFingerprint works similar to metricToFingerprint but uses a
+// faster and less allocation-heavy hash function, which is more susceptible to
+// create hash collisions. Therefore, collision detection should be applied.
+func metricToFastFingerprint(m Metric) Fingerprint {
+	if len(m) == 0 {
+		return Fingerprint(emptyLabelSignature)
+	}
+
+	var result uint64
+	hb := getHashAndBuf()
+	defer putHashAndBuf(hb)
+
+	for labelName, labelValue := range m {
+		hb.b.WriteString(string(labelName))
+		hb.b.WriteByte(SeparatorByte)
+		hb.b.WriteString(string(labelValue))
+		hb.h.Write(hb.b.Bytes())
+		result ^= hb.h.Sum64()
+		hb.h.Reset()
+		hb.b.Reset()
+	}
+	return Fingerprint(result)
+}
+
+// SignatureForLabels works like LabelsToSignature but takes a Metric as
+// parameter (rather than a label map) and only includes the labels with the
+// specified LabelNames into the signature calculation. The labels passed in
+// will be sorted by this function.
+func SignatureForLabels(m Metric, labels LabelNames) uint64 {
+	if len(m) == 0 || len(labels) == 0 {
+		return emptyLabelSignature
+	}
+
+	sort.Sort(labels)
+
+	hb := getHashAndBuf()
+	defer putHashAndBuf(hb)
+
+	for _, label := range labels {
+		hb.b.WriteString(string(label))
+		hb.b.WriteByte(SeparatorByte)
+		hb.b.WriteString(string(m[label]))
+		hb.b.WriteByte(SeparatorByte)
+		hb.h.Write(hb.b.Bytes())
+		hb.b.Reset()
+	}
+	return hb.h.Sum64()
+}
+
+// SignatureWithoutLabels works like LabelsToSignature but takes a Metric as
+// parameter (rather than a label map) and excludes the labels with any of the
+// specified LabelNames from the signature calculation.
+func SignatureWithoutLabels(m Metric, labels map[LabelName]struct{}) uint64 {
+	if len(m) == 0 {
+		return emptyLabelSignature
+	}
+
+	labelNames := make(LabelNames, 0, len(m))
+	for labelName := range m {
+		if _, exclude := labels[labelName]; !exclude {
+			labelNames = append(labelNames, labelName)
+		}
+	}
+	if len(labelNames) == 0 {
+		return emptyLabelSignature
+	}
+	sort.Sort(labelNames)
+
+	hb := getHashAndBuf()
+	defer putHashAndBuf(hb)
+
+	for _, labelName := range labelNames {
+		hb.b.WriteString(string(labelName))
+		hb.b.WriteByte(SeparatorByte)
+		hb.b.WriteString(string(m[labelName]))
+		hb.b.WriteByte(SeparatorByte)
+		hb.h.Write(hb.b.Bytes())
+		hb.b.Reset()
+	}
+	return hb.h.Sum64()
+}

vendor/github.com/prometheus/client_golang/model/timestamp.go

@@ -0,0 +1,116 @@
+// Copyright 2013 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 model
+
+import (
+	"math"
+	"strconv"
+
+	native_time "time"
+)
+
+// Timestamp is the number of milliseconds since the epoch
+// (1970-01-01 00:00 UTC) excluding leap seconds.
+type Timestamp int64
+
+const (
+	// MinimumTick is the minimum supported time resolution. This has to be
+	// at least native_time.Second in order for the code below to work.
+	MinimumTick = native_time.Millisecond
+	// second is the timestamp duration equivalent to one second.
+	second = int64(native_time.Second / MinimumTick)
+	// The number of nanoseconds per minimum tick.
+	nanosPerTick = int64(MinimumTick / native_time.Nanosecond)
+
+	// Earliest is the earliest timestamp representable. Handy for
+	// initializing a high watermark.
+	Earliest = Timestamp(math.MinInt64)
+	// Latest is the latest timestamp representable. Handy for initializing
+	// a low watermark.
+	Latest = Timestamp(math.MaxInt64)
+)
+
+// Equal reports whether two timestamps represent the same instant.
+func (t Timestamp) Equal(o Timestamp) bool {
+	return t == o
+}
+
+// Before reports whether the timestamp t is before o.
+func (t Timestamp) Before(o Timestamp) bool {
+	return t < o
+}
+
+// After reports whether the timestamp t is after o.
+func (t Timestamp) After(o Timestamp) bool {
+	return t > o
+}
+
+// Add returns the Timestamp t + d.
+func (t Timestamp) Add(d native_time.Duration) Timestamp {
+	return t + Timestamp(d/MinimumTick)
+}
+
+// Sub returns the Duration t - o.
+func (t Timestamp) Sub(o Timestamp) native_time.Duration {
+	return native_time.Duration(t-o) * MinimumTick
+}
+
+// Time returns the time.Time representation of t.
+func (t Timestamp) Time() native_time.Time {
+	return native_time.Unix(int64(t)/second, (int64(t)%second)*nanosPerTick)
+}
+
+// Unix returns t as a Unix time, the number of seconds elapsed
+// since January 1, 1970 UTC.
+func (t Timestamp) Unix() int64 {
+	return int64(t) / second
+}
+
+// UnixNano returns t as a Unix time, the number of nanoseconds elapsed
+// since January 1, 1970 UTC.
+func (t Timestamp) UnixNano() int64 {
+	return int64(t) * nanosPerTick
+}
+
+// String returns a string representation of the timestamp.
+func (t Timestamp) String() string {
+	return strconv.FormatFloat(float64(t)/float64(second), 'f', -1, 64)
+}
+
+// MarshalJSON implements the json.Marshaler interface.
+func (t Timestamp) MarshalJSON() ([]byte, error) {
+	return []byte(t.String()), nil
+}
+
+// Now returns the current time as a Timestamp.
+func Now() Timestamp {
+	return TimestampFromTime(native_time.Now())
+}
+
+// TimestampFromTime returns the Timestamp equivalent to the time.Time t.
+func TimestampFromTime(t native_time.Time) Timestamp {
+	return TimestampFromUnixNano(t.UnixNano())
+}
+
+// TimestampFromUnix returns the Timestamp equivalent to the Unix timestamp t
+// provided in seconds.
+func TimestampFromUnix(t int64) Timestamp {
+	return Timestamp(t * second)
+}
+
+// TimestampFromUnixNano returns the Timestamp equivalent to the Unix timestamp
+// t provided in nanoseconds.
+func TimestampFromUnixNano(t int64) Timestamp {
+	return Timestamp(t / nanosPerTick)
+}

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

@@ -1 +1,53 @@
-See [![go-doc](https://godoc.org/github.com/prometheus/client_golang/prometheus?status.svg)](https://godoc.org/github.com/prometheus/client_golang/prometheus).
+# Overview
+This is the [Prometheus](http://www.prometheus.io) telemetric
+instrumentation client [Go](http://golang.org) client library.  It
+enable authors to define process-space metrics for their servers and
+expose them through a web service interface for extraction,
+aggregation, and a whole slew of other post processing techniques.
+
+# Installing
+    $ go get github.com/prometheus/client_golang/prometheus
+
+# Example
+```go
+package main
+
+import (
+	"net/http"
+
+	"github.com/prometheus/client_golang/prometheus"
+)
+
+var (
+	indexed = prometheus.NewCounter(prometheus.CounterOpts{
+		Namespace: "my_company",
+		Subsystem: "indexer",
+		Name:      "documents_indexed",
+		Help:      "The number of documents indexed.",
+	})
+	size = prometheus.NewGauge(prometheus.GaugeOpts{
+		Namespace: "my_company",
+		Subsystem: "storage",
+		Name:      "documents_total_size_bytes",
+		Help:      "The total size of all documents in the storage.",
+	})
+)
+
+func main() {
+	http.Handle("/metrics", prometheus.Handler())
+
+	indexed.Inc()
+	size.Set(5)
+
+	http.ListenAndServe(":8080", nil)
+}
+
+func init() {
+	prometheus.MustRegister(indexed)
+	prometheus.MustRegister(size)
+}
+```
+
+# Documentation
+
+[![GoDoc](https://godoc.org/github.com/prometheus/client_golang?status.png)](https://godoc.org/github.com/prometheus/client_golang)

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

@@ -15,15 +15,15 @@ package prometheus
 
 // Collector is the interface implemented by anything that can be used by
 // Prometheus to collect metrics. A Collector has to be registered for
-// collection. See Registerer.Register.
+// collection. See Register, MustRegister, RegisterOrGet, and MustRegisterOrGet.
 //
-// The stock metrics provided by this package (Gauge, Counter, Summary,
-// Histogram, Untyped) are also Collectors (which only ever collect one metric,
-// namely itself). An implementer of Collector may, however, collect multiple
-// metrics in a coordinated fashion and/or create metrics on the fly. Examples
-// for collectors already implemented in this library are the metric vectors
-// (i.e. collection of multiple instances of the same Metric but with different
-// label values) like GaugeVec or SummaryVec, and the ExpvarCollector.
+// The stock metrics provided by this package (like Gauge, Counter, Summary) are
+// also Collectors (which only ever collect one metric, namely itself). An
+// implementer of Collector may, however, collect multiple metrics in a
+// coordinated fashion and/or create metrics on the fly. Examples for collectors
+// already implemented in this library are the metric vectors (i.e. collection
+// of multiple instances of the same Metric but with different label values)
+// like GaugeVec or SummaryVec, and the ExpvarCollector.
 type Collector interface {
 	// Describe sends the super-set of all possible descriptors of metrics
 	// collected by this Collector to the provided channel and returns once
@@ -37,39 +37,39 @@ type Collector interface {
 	// 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
-	// Describe. Returned metrics that share the same descriptor must differ
-	// in their variable label values. This method may be called
-	// concurrently and must therefore be 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 is called by Prometheus 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 Describe. Returned
+	// metrics that share the same descriptor must differ in their variable
+	// label values. This method may be called concurrently and must
+	// therefore be 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)
 }
 
-// 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.
-type selfCollector struct {
+// SelfCollector implements Collector for a single Metric so that 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.
+type SelfCollector struct {
 	self Metric
 }
 
-// init provides the selfCollector with a reference to the metric it is supposed
+// Init provides the SelfCollector with a reference to the metric it is supposed
 // to collect. It is usually called within the factory function to create a
 // metric. See example.
-func (c *selfCollector) init(self Metric) {
+func (c *SelfCollector) Init(self Metric) {
 	c.self = self
 }
 
 // Describe implements Collector.
-func (c *selfCollector) Describe(ch chan<- *Desc) {
+func (c *SelfCollector) Describe(ch chan<- *Desc) {
 	ch <- c.self.Desc()
 }
 
 // Collect implements Collector.
-func (c *selfCollector) Collect(ch chan<- Metric) {
+func (c *SelfCollector) Collect(ch chan<- Metric) {
 	ch <- c.self
 }

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

@@ -15,6 +15,7 @@ package prometheus
 
 import (
 	"errors"
+	"hash/fnv"
 )
 
 // Counter is a Metric that represents a single numerical value that only ever
@@ -35,9 +36,6 @@ type Counter interface {
 	// Prometheus metric. Do not use it for regular handling of a
 	// Prometheus counter (as it can be used to break the contract of
 	// monotonically increasing values).
-	//
-	// Deprecated: Use NewConstMetric to create a counter for an external
-	// value. A Counter should never be set.
 	Set(float64)
 	// Inc increments the counter by 1.
 	Inc()
@@ -58,7 +56,7 @@ func NewCounter(opts CounterOpts) Counter {
 		opts.ConstLabels,
 	)
 	result := &counter{value: value{desc: desc, valType: CounterValue, labelPairs: desc.constLabelPairs}}
-	result.init(result) // Init self-collection.
+	result.Init(result) // Init self-collection.
 	return result
 }
 
@@ -82,7 +80,7 @@ func (c *counter) Add(v float64) {
 // CounterVec embeds MetricVec. See there for a full list of methods with
 // detailed documentation.
 type CounterVec struct {
-	*MetricVec
+	MetricVec
 }
 
 // NewCounterVec creates a new CounterVec based on the provided CounterOpts and
@@ -96,15 +94,20 @@ func NewCounterVec(opts CounterOpts, labelNames []string) *CounterVec {
 		opts.ConstLabels,
 	)
 	return &CounterVec{
-		MetricVec: newMetricVec(desc, func(lvs ...string) Metric {
-			result := &counter{value: value{
-				desc:       desc,
-				valType:    CounterValue,
-				labelPairs: makeLabelPairs(desc, lvs),
-			}}
-			result.init(result) // Init self-collection.
-			return result
-		}),
+		MetricVec: MetricVec{
+			children: map[uint64]Metric{},
+			desc:     desc,
+			hash:     fnv.New64a(),
+			newMetric: func(lvs ...string) Metric {
+				result := &counter{value: value{
+					desc:       desc,
+					valType:    CounterValue,
+					labelPairs: makeLabelPairs(desc, lvs),
+				}}
+				result.Init(result) // Init self-collection.
+				return result
+			},
+		},
 	}
 }
 

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

@@ -1,21 +1,10 @@
-// Copyright 2016 The Prometheus Authors
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-// http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
 package prometheus
 
 import (
+	"bytes"
 	"errors"
 	"fmt"
+	"hash/fnv"
 	"regexp"
 	"sort"
 	"strings"
@@ -23,17 +12,14 @@ import (
 	"github.com/golang/protobuf/proto"
 
 	dto "github.com/prometheus/client_model/go"
+
+	"github.com/prometheus/client_golang/model"
 )
 
 var (
 	metricNameRE = regexp.MustCompile(`^[a-zA-Z_][a-zA-Z0-9_:]*$`)
-	labelNameRE  = regexp.MustCompile("^[a-zA-Z_][a-zA-Z0-9_]*$")
 )
 
-// reservedLabelPrefix is a prefix which is not legal in user-supplied
-// label names.
-const reservedLabelPrefix = "__"
-
 // Labels represents a collection of label name -> value mappings. This type is
 // commonly used with the With(Labels) and GetMetricWith(Labels) methods of
 // metric vector Collectors, e.g.:
@@ -78,7 +64,7 @@ type Desc struct {
 	// Help string. Each Desc with the same fqName must have the same
 	// dimHash.
 	dimHash uint64
-	// err is an error that occurred during construction. It is reported on
+	// err is an error that occured during construction. It is reported on
 	// registration time.
 	err error
 }
@@ -142,24 +128,31 @@ func NewDesc(fqName, help string, variableLabels []string, constLabels Labels) *
 		d.err = errors.New("duplicate label names")
 		return d
 	}
-	vh := hashNew()
+	h := fnv.New64a()
+	var b bytes.Buffer // To copy string contents into, avoiding []byte allocations.
 	for _, val := range labelValues {
-		vh = hashAdd(vh, val)
-		vh = hashAddByte(vh, separatorByte)
+		b.Reset()
+		b.WriteString(val)
+		b.WriteByte(model.SeparatorByte)
+		h.Write(b.Bytes())
 	}
-	d.id = vh
+	d.id = h.Sum64()
 	// Sort labelNames so that order doesn't matter for the hash.
 	sort.Strings(labelNames)
 	// Now hash together (in this order) the help string and the sorted
 	// label names.
-	lh := hashNew()
-	lh = hashAdd(lh, help)
-	lh = hashAddByte(lh, separatorByte)
+	h.Reset()
+	b.Reset()
+	b.WriteString(help)
+	b.WriteByte(model.SeparatorByte)
+	h.Write(b.Bytes())
 	for _, labelName := range labelNames {
-		lh = hashAdd(lh, labelName)
-		lh = hashAddByte(lh, separatorByte)
+		b.Reset()
+		b.WriteString(labelName)
+		b.WriteByte(model.SeparatorByte)
+		h.Write(b.Bytes())
 	}
-	d.dimHash = lh
+	d.dimHash = h.Sum64()
 
 	d.constLabelPairs = make([]*dto.LabelPair, 0, len(constLabels))
 	for n, v := range constLabels {
@@ -200,6 +193,6 @@ func (d *Desc) String() string {
 }
 
 func checkLabelName(l string) bool {
-	return labelNameRE.MatchString(l) &&
-		!strings.HasPrefix(l, reservedLabelPrefix)
+	return model.LabelNameRE.MatchString(l) &&
+		!strings.HasPrefix(l, model.ReservedLabelPrefix)
 }

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

@@ -11,17 +11,18 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-// Package prometheus provides metrics primitives to instrument code for
-// monitoring. It also offers a registry for metrics. Sub-packages allow to
-// expose the registered metrics via HTTP (package promhttp) or push them to a
-// Pushgateway (package push).
+// Package prometheus provides embeddable metric primitives for servers and
+// standardized exposition of telemetry through a web services interface.
 //
 // All exported functions and methods are safe to be used concurrently unless
-//specified otherwise.
+// specified otherwise.
 //
-// A Basic Example
+// To expose metrics registered with the Prometheus registry, an HTTP server
+// needs to know about the Prometheus handler. The usual endpoint is "/metrics".
 //
-// As a starting point, a very basic usage example:
+//     http.Handle("/metrics", prometheus.Handler())
+//
+// As a starting point a very basic usage example:
 //
 //    package main
 //
@@ -29,7 +30,6 @@
 //    	"net/http"
 //
 //    	"github.com/prometheus/client_golang/prometheus"
-//    	"github.com/prometheus/client_golang/prometheus/promhttp"
 //    )
 //
 //    var (
@@ -37,145 +37,73 @@
 //    		Name: "cpu_temperature_celsius",
 //    		Help: "Current temperature of the CPU.",
 //    	})
-//    	hdFailures = prometheus.NewCounterVec(
-//    		prometheus.CounterOpts{
-//    			Name: "hd_errors_total",
-//    			Help: "Number of hard-disk errors.",
-//    		},
-//    		[]string{"device"},
-//    	)
+//    	hdFailures = prometheus.NewCounter(prometheus.CounterOpts{
+//    		Name: "hd_errors_total",
+//    		Help: "Number of hard-disk errors.",
+//    	})
 //    )
 //
 //    func init() {
-//    	// Metrics have to be registered to be exposed:
 //    	prometheus.MustRegister(cpuTemp)
 //    	prometheus.MustRegister(hdFailures)
 //    }
 //
 //    func main() {
 //    	cpuTemp.Set(65.3)
-//    	hdFailures.With(prometheus.Labels{"device":"/dev/sda"}).Inc()
+//    	hdFailures.Inc()
 //
-//    	// The Handler function provides a default handler to expose metrics
-//    	// via an HTTP server. "/metrics" is the usual endpoint for that.
-//    	http.Handle("/metrics", promhttp.Handler())
+//    	http.Handle("/metrics", prometheus.Handler())
 //    	http.ListenAndServe(":8080", nil)
 //    }
 //
 //
-// This is a complete program that exports two metrics, a Gauge and a Counter,
-// the latter with a label attached to turn it into a (one-dimensional) vector.
+// This is a complete program that exports two metrics, a Gauge and a Counter.
+// It also exports some stats about the HTTP usage of the /metrics
+// endpoint. (See the Handler function for more detail.)
 //
-// Metrics
+// Two more advanced metric types are the Summary and Histogram.
 //
-// The number of exported identifiers in this package might appear a bit
-// overwhelming. Hovever, in addition to the basic plumbing shown in the example
-// above, you only need to understand the different metric types and their
-// vector versions for basic usage.
-//
-// Above, you have already touched the Counter and the Gauge. There are two more
-// advanced metric types: the Summary and Histogram. A more thorough description
-// of those four metric types can be found in the Prometheus docs:
-// https://prometheus.io/docs/concepts/metric_types/
-//
-// A fifth "type" of metric is Untyped. It behaves like a Gauge, but signals the
-// Prometheus server not to assume anything about its type.
-//
-// In addition to the fundamental metric types Gauge, Counter, Summary,
-// Histogram, and Untyped, a very important part of the Prometheus data model is
-// the partitioning of samples along dimensions called labels, which results in
+// In addition to the fundamental metric types Gauge, Counter, Summary, and
+// Histogram, a very important part of the Prometheus data model is the
+// partitioning of samples along dimensions called labels, which results in
 // metric vectors. The fundamental types are GaugeVec, CounterVec, SummaryVec,
-// HistogramVec, and UntypedVec.
+// and HistogramVec.
 //
-// While only the fundamental metric types implement the Metric interface, both
-// the metrics and their vector versions implement the Collector interface. A
-// Collector manages the collection of a number of Metrics, but for convenience,
-// a Metric can also “collect itself”. Note that Gauge, Counter, Summary,
-// Histogram, and Untyped are interfaces themselves while GaugeVec, CounterVec,
-// SummaryVec, HistogramVec, and UntypedVec are not.
+// Those are all the parts needed for basic usage. Detailed documentation and
+// examples are provided below.
 //
-// To create instances of Metrics and their vector versions, you need a suitable
-// …Opts struct, i.e. GaugeOpts, CounterOpts, SummaryOpts,
-// HistogramOpts, or UntypedOpts.
+// Everything else this package offers is essentially for "power users" only. A
+// few pointers to "power user features":
 //
-// Custom Collectors and constant Metrics
+// All the various ...Opts structs have a ConstLabels field for labels that
+// never change their value (which is only useful under special circumstances,
+// see documentation of the Opts type).
 //
-// While you could create your own implementations of Metric, most likely you
-// will only ever implement the Collector interface on your own. At a first
-// glance, a custom Collector seems handy to bundle Metrics for common
-// registration (with the prime example of the different metric vectors above,
-// which bundle all the metrics of the same name but with different labels).
+// The Untyped metric behaves like a Gauge, but signals the Prometheus server
+// not to assume anything about its type.
 //
-// There is a more involved use case, too: If you already have metrics
-// available, created outside of the Prometheus context, you don't need the
-// interface of the various Metric types. You essentially want to mirror the
-// existing numbers into Prometheus Metrics during collection. An own
-// implementation of the Collector interface is perfect for that. You can create
-// Metric instances “on the fly” using NewConstMetric, NewConstHistogram, and
-// NewConstSummary (and their respective Must… versions). That will happen in
-// the Collect method. The Describe method has to return separate Desc
-// instances, representative of the “throw-away” metrics to be created
-// later. NewDesc comes in handy to create those Desc instances.
+// Functions to fine-tune how the metric registry works: EnableCollectChecks,
+// PanicOnCollectError, Register, Unregister, SetMetricFamilyInjectionHook.
 //
-// The Collector example illustrates the use case. You can also look at the
-// source code of the processCollector (mirroring process metrics), the
-// goCollector (mirroring Go metrics), or the expvarCollector (mirroring expvar
-// metrics) as examples that are used in this package itself.
+// For custom metric collection, there are two entry points: Custom Metric
+// implementations and custom Collector implementations. A Metric is the
+// fundamental unit in the Prometheus data model: a sample at a point in time
+// together with its meta-data (like its fully-qualified name and any number of
+// pairs of label name and label value) that knows how to marshal itself into a
+// data transfer object (aka DTO, implemented as a protocol buffer). A Collector
+// gets registered with the Prometheus registry and manages the collection of
+// one or more Metrics. Many parts of this package are building blocks for
+// Metrics and Collectors. Desc is the metric descriptor, actually used by all
+// metrics under the hood, and by Collectors to describe the Metrics to be
+// collected, but only to be dealt with by users if they implement their own
+// Metrics or Collectors. To create a Desc, the BuildFQName function will come
+// in handy. Other useful components for Metric and Collector implementation
+// include: LabelPairSorter to sort the DTO version of label pairs,
+// NewConstMetric and MustNewConstMetric to create "throw away" Metrics at
+// collection time, MetricVec to bundle custom Metrics into a metric vector
+// Collector, SelfCollector to make a custom Metric collect itself.
 //
-// If you just need to call a function to get a single float value to collect as
-// a metric, GaugeFunc, CounterFunc, or UntypedFunc might be interesting
-// shortcuts.
-//
-// Advanced Uses of the Registry
-//
-// While MustRegister is the by far most common way of registering a Collector,
-// sometimes you might want to handle the errors the registration might
-// cause. As suggested by the name, MustRegister panics if an error occurs. With
-// the Register function, the error is returned and can be handled.
-//
-// An error is returned if the registered Collector is incompatible or
-// inconsistent with already registered metrics. The registry aims for
-// consistency of the collected metrics according to the Prometheus data
-// model. Inconsistencies are ideally detected at registration time, not at
-// collect time. The former will usually be detected at start-up time of a
-// program, while the latter will only happen at scrape time, possibly not even
-// on the first scrape if the inconsistency only becomes relevant later. That is
-// the main reason why a Collector and a Metric have to describe themselves to
-// the registry.
-//
-// So far, everything we did operated on the so-called default registry, as it
-// can be found in the global DefaultRegistry variable. With NewRegistry, you
-// can create a custom registry, or you can even implement the Registerer or
-// Gatherer interfaces yourself. The methods Register and Unregister work in
-// the same way on a custom registry as the global functions Register and
-// Unregister on the default registry.
-//
-// There are a number of uses for custom registries: You can use registries
-// with special properties, see NewPedanticRegistry. You can avoid global state,
-// as it is imposed by the DefaultRegistry. You can use multiple registries at
-// the same time to expose different metrics in different ways. You can use
-// separate registries for testing purposes.
-//
-// Also note that the DefaultRegistry comes registered with a Collector for Go
-// runtime metrics (via NewGoCollector) and a Collector for process metrics (via
-// NewProcessCollector). With a custom registry, you are in control and decide
-// yourself about the Collectors to register.
-//
-// HTTP Exposition
-//
-// The Registry implements the Gatherer interface. The caller of the Gather
-// method can then expose the gathered metrics in some way. Usually, the metrics
-// are served via HTTP on the /metrics endpoint. That's happening in the example
-// above. The tools to expose metrics via HTTP are in the promhttp
-// sub-package. (The top-level functions in the prometheus package are
-// deprecated.)
-//
-// Pushing to the Pushgateway
-//
-// Function for pushing to the Pushgateway can be found in the push sub-package.
-//
-// Other Means of Exposition
-//
-// More ways of exposing metrics can easily be added. Sending metrics to
-// Graphite would be an example that will soon be implemented.
+// A good example for a custom Collector is the ExpVarCollector included in this
+// package, which exports variables exported via the "expvar" package as
+// Prometheus metrics.
 package prometheus

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

@@ -18,21 +18,21 @@ import (
 	"expvar"
 )
 
-type expvarCollector struct {
+// ExpvarCollector collects metrics from the expvar interface. It provides a
+// quick way to expose numeric values that are already exported via expvar as
+// Prometheus metrics. Note that the data models of expvar and Prometheus are
+// fundamentally different, and that the ExpvarCollector is inherently
+// slow. Thus, the ExpvarCollector is probably great for experiments and
+// prototying, but you should seriously consider a more direct implementation of
+// Prometheus metrics for monitoring production systems.
+//
+// Use NewExpvarCollector to create new instances.
+type ExpvarCollector struct {
 	exports map[string]*Desc
 }
 
-// NewExpvarCollector returns a newly allocated expvar Collector that still has
-// to be registered with a Prometheus registry.
-//
-// An expvar Collector collects metrics from the expvar interface. It provides a
-// quick way to expose numeric values that are already exported via expvar as
-// Prometheus metrics. Note that the data models of expvar and Prometheus are
-// fundamentally different, and that the expvar Collector is inherently slower
-// than native Prometheus metrics. Thus, the expvar Collector is probably great
-// for experiments and prototying, but you should seriously consider a more
-// direct implementation of Prometheus metrics for monitoring production
-// systems.
+// NewExpvarCollector returns a newly allocated ExpvarCollector that still has
+// to be registered with the Prometheus registry.
 //
 // The exports map has the following meaning:
 //
@@ -59,21 +59,21 @@ type expvarCollector struct {
 // sample values.
 //
 // Anything that does not fit into the scheme above is silently ignored.
-func NewExpvarCollector(exports map[string]*Desc) Collector {
-	return &expvarCollector{
+func NewExpvarCollector(exports map[string]*Desc) *ExpvarCollector {
+	return &ExpvarCollector{
 		exports: exports,
 	}
 }
 
 // Describe implements Collector.
-func (e *expvarCollector) Describe(ch chan<- *Desc) {
+func (e *ExpvarCollector) Describe(ch chan<- *Desc) {
 	for _, desc := range e.exports {
 		ch <- desc
 	}
 }
 
 // Collect implements Collector.
-func (e *expvarCollector) Collect(ch chan<- Metric) {
+func (e *ExpvarCollector) Collect(ch chan<- Metric) {
 	for name, desc := range e.exports {
 		var m Metric
 		expVar := expvar.Get(name)

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

@@ -1,29 +0,0 @@
-package prometheus
-
-// Inline and byte-free variant of hash/fnv's fnv64a.
-
-const (
-	offset64 = 14695981039346656037
-	prime64  = 1099511628211
-)
-
-// hashNew initializies a new fnv64a hash value.
-func hashNew() uint64 {
-	return offset64
-}
-
-// hashAdd adds a string to a fnv64a hash value, returning the updated hash.
-func hashAdd(h uint64, s string) uint64 {
-	for i := 0; i < len(s); i++ {
-		h ^= uint64(s[i])
-		h *= prime64
-	}
-	return h
-}
-
-// hashAddByte adds a byte to a fnv64a hash value, returning the updated hash.
-func hashAddByte(h uint64, b byte) uint64 {
-	h ^= uint64(b)
-	h *= prime64
-	return h
-}

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

@@ -13,6 +13,8 @@
 
 package prometheus
 
+import "hash/fnv"
+
 // Gauge is a Metric that represents a single numerical value that can
 // arbitrarily go up and down.
 //
@@ -58,7 +60,7 @@ func NewGauge(opts GaugeOpts) Gauge {
 // (e.g. number of operations queued, partitioned by user and operation
 // type). Create instances with NewGaugeVec.
 type GaugeVec struct {
-	*MetricVec
+	MetricVec
 }
 
 // NewGaugeVec creates a new GaugeVec based on the provided GaugeOpts and
@@ -72,9 +74,14 @@ func NewGaugeVec(opts GaugeOpts, labelNames []string) *GaugeVec {
 		opts.ConstLabels,
 	)
 	return &GaugeVec{
-		MetricVec: newMetricVec(desc, func(lvs ...string) Metric {
-			return newValue(desc, GaugeValue, 0, lvs...)
-		}),
+		MetricVec: MetricVec{
+			children: map[uint64]Metric{},
+			desc:     desc,
+			hash:     fnv.New64a(),
+			newMetric: func(lvs ...string) Metric {
+				return newValue(desc, GaugeValue, 0, lvs...)
+			},
+		},
 	}
 }
 

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

@@ -1,7 +1,6 @@
 package prometheus
 
 import (
-	"fmt"
 	"runtime"
 	"runtime/debug"
 	"time"
@@ -10,226 +9,27 @@ import (
 type goCollector struct {
 	goroutines Gauge
 	gcDesc     *Desc
-
-	// metrics to describe and collect
-	metrics memStatsMetrics
 }
 
 // NewGoCollector returns a collector which exports metrics about the current
 // go process.
-func NewGoCollector() Collector {
+func NewGoCollector() *goCollector {
 	return &goCollector{
 		goroutines: NewGauge(GaugeOpts{
-			Namespace: "go",
-			Name:      "goroutines",
-			Help:      "Number of goroutines that currently exist.",
+			Name: "go_goroutines",
+			Help: "Number of goroutines that currently exist.",
 		}),
 		gcDesc: NewDesc(
 			"go_gc_duration_seconds",
 			"A summary of the GC invocation durations.",
 			nil, nil),
-		metrics: memStatsMetrics{
-			{
-				desc: NewDesc(
-					memstatNamespace("alloc_bytes"),
-					"Number of bytes allocated and still in use.",
-					nil, nil,
-				),
-				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.Alloc) },
-				valType: GaugeValue,
-			}, {
-				desc: NewDesc(
-					memstatNamespace("alloc_bytes_total"),
-					"Total number of bytes allocated, even if freed.",
-					nil, nil,
-				),
-				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.TotalAlloc) },
-				valType: CounterValue,
-			}, {
-				desc: NewDesc(
-					memstatNamespace("sys_bytes"),
-					"Number of bytes obtained by system. Sum of all system allocations.",
-					nil, nil,
-				),
-				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.Sys) },
-				valType: GaugeValue,
-			}, {
-				desc: NewDesc(
-					memstatNamespace("lookups_total"),
-					"Total number of pointer lookups.",
-					nil, nil,
-				),
-				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.Lookups) },
-				valType: CounterValue,
-			}, {
-				desc: NewDesc(
-					memstatNamespace("mallocs_total"),
-					"Total number of mallocs.",
-					nil, nil,
-				),
-				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.Mallocs) },
-				valType: CounterValue,
-			}, {
-				desc: NewDesc(
-					memstatNamespace("frees_total"),
-					"Total number of frees.",
-					nil, nil,
-				),
-				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.Frees) },
-				valType: CounterValue,
-			}, {
-				desc: NewDesc(
-					memstatNamespace("heap_alloc_bytes"),
-					"Number of heap bytes allocated and still in use.",
-					nil, nil,
-				),
-				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.HeapAlloc) },
-				valType: GaugeValue,
-			}, {
-				desc: NewDesc(
-					memstatNamespace("heap_sys_bytes"),
-					"Number of heap bytes obtained from system.",
-					nil, nil,
-				),
-				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.HeapSys) },
-				valType: GaugeValue,
-			}, {
-				desc: NewDesc(
-					memstatNamespace("heap_idle_bytes"),
-					"Number of heap bytes waiting to be used.",
-					nil, nil,
-				),
-				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.HeapIdle) },
-				valType: GaugeValue,
-			}, {
-				desc: NewDesc(
-					memstatNamespace("heap_inuse_bytes"),
-					"Number of heap bytes that are in use.",
-					nil, nil,
-				),
-				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.HeapInuse) },
-				valType: GaugeValue,
-			}, {
-				desc: NewDesc(
-					memstatNamespace("heap_released_bytes_total"),
-					"Total number of heap bytes released to OS.",
-					nil, nil,
-				),
-				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.HeapReleased) },
-				valType: CounterValue,
-			}, {
-				desc: NewDesc(
-					memstatNamespace("heap_objects"),
-					"Number of allocated objects.",
-					nil, nil,
-				),
-				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.HeapObjects) },
-				valType: GaugeValue,
-			}, {
-				desc: NewDesc(
-					memstatNamespace("stack_inuse_bytes"),
-					"Number of bytes in use by the stack allocator.",
-					nil, nil,
-				),
-				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.StackInuse) },
-				valType: GaugeValue,
-			}, {
-				desc: NewDesc(
-					memstatNamespace("stack_sys_bytes"),
-					"Number of bytes obtained from system for stack allocator.",
-					nil, nil,
-				),
-				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.StackSys) },
-				valType: GaugeValue,
-			}, {
-				desc: NewDesc(
-					memstatNamespace("mspan_inuse_bytes"),
-					"Number of bytes in use by mspan structures.",
-					nil, nil,
-				),
-				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.MSpanInuse) },
-				valType: GaugeValue,
-			}, {
-				desc: NewDesc(
-					memstatNamespace("mspan_sys_bytes"),
-					"Number of bytes used for mspan structures obtained from system.",
-					nil, nil,
-				),
-				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.MSpanSys) },
-				valType: GaugeValue,
-			}, {
-				desc: NewDesc(
-					memstatNamespace("mcache_inuse_bytes"),
-					"Number of bytes in use by mcache structures.",
-					nil, nil,
-				),
-				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.MCacheInuse) },
-				valType: GaugeValue,
-			}, {
-				desc: NewDesc(
-					memstatNamespace("mcache_sys_bytes"),
-					"Number of bytes used for mcache structures obtained from system.",
-					nil, nil,
-				),
-				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.MCacheSys) },
-				valType: GaugeValue,
-			}, {
-				desc: NewDesc(
-					memstatNamespace("buck_hash_sys_bytes"),
-					"Number of bytes used by the profiling bucket hash table.",
-					nil, nil,
-				),
-				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.BuckHashSys) },
-				valType: GaugeValue,
-			}, {
-				desc: NewDesc(
-					memstatNamespace("gc_sys_bytes"),
-					"Number of bytes used for garbage collection system metadata.",
-					nil, nil,
-				),
-				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.GCSys) },
-				valType: GaugeValue,
-			}, {
-				desc: NewDesc(
-					memstatNamespace("other_sys_bytes"),
-					"Number of bytes used for other system allocations.",
-					nil, nil,
-				),
-				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.OtherSys) },
-				valType: GaugeValue,
-			}, {
-				desc: NewDesc(
-					memstatNamespace("next_gc_bytes"),
-					"Number of heap bytes when next garbage collection will take place.",
-					nil, nil,
-				),
-				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.NextGC) },
-				valType: GaugeValue,
-			}, {
-				desc: NewDesc(
-					memstatNamespace("last_gc_time_seconds"),
-					"Number of seconds since 1970 of last garbage collection.",
-					nil, nil,
-				),
-				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.LastGC) / 1e9 },
-				valType: GaugeValue,
-			},
-		},
 	}
 }
 
-func memstatNamespace(s string) string {
-	return fmt.Sprintf("go_memstats_%s", s)
-}
-
 // Describe returns all descriptions of the collector.
 func (c *goCollector) Describe(ch chan<- *Desc) {
 	ch <- c.goroutines.Desc()
 	ch <- c.gcDesc
-
-	for _, i := range c.metrics {
-		ch <- i.desc
-	}
 }
 
 // Collect returns the current state of all metrics of the collector.
@@ -247,17 +47,4 @@ func (c *goCollector) Collect(ch chan<- Metric) {
 	}
 	quantiles[0.0] = stats.PauseQuantiles[0].Seconds()
 	ch <- MustNewConstSummary(c.gcDesc, uint64(stats.NumGC), float64(stats.PauseTotal.Seconds()), quantiles)
-
-	ms := &runtime.MemStats{}
-	runtime.ReadMemStats(ms)
-	for _, i := range c.metrics {
-		ch <- MustNewConstMetric(i.desc, i.valType, i.eval(ms))
-	}
-}
-
-// memStatsMetrics provide description, value, and value type for memstat metrics.
-type memStatsMetrics []struct {
-	desc    *Desc
-	eval    func(*runtime.MemStats) float64
-	valType ValueType
 }

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

@@ -15,12 +15,14 @@ package prometheus
 
 import (
 	"fmt"
+	"hash/fnv"
 	"math"
 	"sort"
 	"sync/atomic"
 
 	"github.com/golang/protobuf/proto"
 
+	"github.com/prometheus/client_golang/model"
 	dto "github.com/prometheus/client_model/go"
 )
 
@@ -47,19 +49,15 @@ type Histogram interface {
 	Observe(float64)
 }
 
-// bucketLabel is used for the label that defines the upper bound of a
-// bucket of a histogram ("le" -> "less or equal").
-const bucketLabel = "le"
-
-// DefBuckets are the default Histogram buckets. The default buckets are
-// tailored to broadly measure the response time (in seconds) of a network
-// service. Most likely, however, you will be required to define buckets
-// customized to your use case.
 var (
+	// DefBuckets are the default Histogram buckets. The default buckets are
+	// tailored to broadly measure the response time (in seconds) of a
+	// network service. Most likely, however, you will be required to define
+	// buckets customized to your use case.
 	DefBuckets = []float64{.005, .01, .025, .05, .1, .25, .5, 1, 2.5, 5, 10}
 
 	errBucketLabelNotAllowed = fmt.Errorf(
-		"%q is not allowed as label name in histograms", bucketLabel,
+		"%q is not allowed as label name in histograms", model.BucketLabel,
 	)
 )
 
@@ -173,12 +171,12 @@ func newHistogram(desc *Desc, opts HistogramOpts, labelValues ...string) Histogr
 	}
 
 	for _, n := range desc.variableLabels {
-		if n == bucketLabel {
+		if n == model.BucketLabel {
 			panic(errBucketLabelNotAllowed)
 		}
 	}
 	for _, lp := range desc.constLabelPairs {
-		if lp.GetName() == bucketLabel {
+		if lp.GetName() == model.BucketLabel {
 			panic(errBucketLabelNotAllowed)
 		}
 	}
@@ -210,7 +208,7 @@ func newHistogram(desc *Desc, opts HistogramOpts, labelValues ...string) Histogr
 	// Finally we know the final length of h.upperBounds and can make counts.
 	h.counts = make([]uint64, len(h.upperBounds))
 
-	h.init(h) // Init self-collection.
+	h.Init(h) // Init self-collection.
 	return h
 }
 
@@ -222,7 +220,7 @@ type histogram struct {
 	sumBits uint64
 	count   uint64
 
-	selfCollector
+	SelfCollector
 	// Note that there is no mutex required.
 
 	desc *Desc
@@ -287,7 +285,7 @@ func (h *histogram) Write(out *dto.Metric) error {
 // (e.g. HTTP request latencies, partitioned by status code and method). Create
 // instances with NewHistogramVec.
 type HistogramVec struct {
-	*MetricVec
+	MetricVec
 }
 
 // NewHistogramVec creates a new HistogramVec based on the provided HistogramOpts and
@@ -301,9 +299,14 @@ func NewHistogramVec(opts HistogramOpts, labelNames []string) *HistogramVec {
 		opts.ConstLabels,
 	)
 	return &HistogramVec{
-		MetricVec: newMetricVec(desc, func(lvs ...string) Metric {
-			return newHistogram(desc, opts, lvs...)
-		}),
+		MetricVec: MetricVec{
+			children: map[uint64]Metric{},
+			desc:     desc,
+			hash:     fnv.New64a(),
+			newMetric: func(lvs ...string) Metric {
+				return newHistogram(desc, opts, lvs...)
+			},
+		},
 	}
 }
 

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

@@ -15,114 +15,14 @@ package prometheus
 
 import (
 	"bufio"
-	"bytes"
-	"compress/gzip"
-	"fmt"
 	"io"
 	"net"
 	"net/http"
 	"strconv"
 	"strings"
-	"sync"
 	"time"
-
-	"github.com/prometheus/common/expfmt"
 )
 
-// TODO(beorn7): Remove this whole file. It is a partial mirror of
-// promhttp/http.go (to avoid circular import chains) where everything HTTP
-// related should live. The functions here are just for avoiding
-// breakage. Everything is deprecated.
-
-const (
-	contentTypeHeader     = "Content-Type"
-	contentLengthHeader   = "Content-Length"
-	contentEncodingHeader = "Content-Encoding"
-	acceptEncodingHeader  = "Accept-Encoding"
-)
-
-var bufPool sync.Pool
-
-func getBuf() *bytes.Buffer {
-	buf := bufPool.Get()
-	if buf == nil {
-		return &bytes.Buffer{}
-	}
-	return buf.(*bytes.Buffer)
-}
-
-func giveBuf(buf *bytes.Buffer) {
-	buf.Reset()
-	bufPool.Put(buf)
-}
-
-// Handler returns an HTTP handler for the DefaultGatherer. It is
-// already instrumented with InstrumentHandler (using "prometheus" as handler
-// name).
-//
-// Deprecated: Please note the issues described in the doc comment of
-// InstrumentHandler. You might want to consider using promhttp.Handler instead
-// (which is non instrumented).
-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.
-func UninstrumentedHandler() http.Handler {
-	return http.HandlerFunc(func(w http.ResponseWriter, req *http.Request) {
-		mfs, err := DefaultGatherer.Gather()
-		if err != nil {
-			http.Error(w, "An error has occurred during metrics collection:\n\n"+err.Error(), http.StatusInternalServerError)
-			return
-		}
-
-		contentType := expfmt.Negotiate(req.Header)
-		buf := getBuf()
-		defer giveBuf(buf)
-		writer, encoding := decorateWriter(req, buf)
-		enc := expfmt.NewEncoder(writer, contentType)
-		var lastErr error
-		for _, mf := range mfs {
-			if err := enc.Encode(mf); err != nil {
-				lastErr = err
-				http.Error(w, "An error has occurred during metrics encoding:\n\n"+err.Error(), http.StatusInternalServerError)
-				return
-			}
-		}
-		if closer, ok := writer.(io.Closer); ok {
-			closer.Close()
-		}
-		if lastErr != nil && buf.Len() == 0 {
-			http.Error(w, "No metrics encoded, last error:\n\n"+err.Error(), http.StatusInternalServerError)
-			return
-		}
-		header := w.Header()
-		header.Set(contentTypeHeader, string(contentType))
-		header.Set(contentLengthHeader, fmt.Sprint(buf.Len()))
-		if encoding != "" {
-			header.Set(contentEncodingHeader, encoding)
-		}
-		w.Write(buf.Bytes())
-	})
-}
-
-// decorateWriter wraps a writer to handle gzip compression if requested.  It
-// returns the decorated writer and the appropriate "Content-Encoding" header
-// (which is empty if no compression is enabled).
-func decorateWriter(request *http.Request, writer io.Writer) (io.Writer, string) {
-	header := request.Header.Get(acceptEncodingHeader)
-	parts := strings.Split(header, ",")
-	for _, part := range parts {
-		part := strings.TrimSpace(part)
-		if part == "gzip" || strings.HasPrefix(part, "gzip;") {
-			return gzip.NewWriter(writer), "gzip"
-		}
-	}
-	return writer, ""
-}
-
 var instLabels = []string{"method", "code"}
 
 type nower interface {
@@ -157,34 +57,12 @@ func nowSeries(t ...time.Time) nower {
 // has a constant label named "handler" with the provided handlerName as
 // value. http_requests_total is a metric vector partitioned by HTTP method
 // (label name "method") and HTTP status code (label name "code").
-//
-// Deprecated: InstrumentHandler has several issues:
-//
-// - It uses Summaries rather than Histograms. Summaries are not useful if
-// aggregation across multiple instances is required.
-//
-// - It uses microseconds as unit, which is deprecated and should be replaced by
-// seconds.
-//
-// - 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.
-//
-// Upcoming versions of this package will provide ways of instrumenting HTTP
-// handlers that are more flexible and have fewer issues. Please prefer direct
-// instrumentation in the meantime.
 func InstrumentHandler(handlerName string, handler http.Handler) http.HandlerFunc {
 	return InstrumentHandlerFunc(handlerName, handler.ServeHTTP)
 }
 
 // InstrumentHandlerFunc wraps the given function for instrumentation. It
-// otherwise works in the same way as InstrumentHandler (and shares the same
-// issues).
-//
-// Deprecated: InstrumentHandlerFunc is deprecated for the same reasons as
-// InstrumentHandler is.
+// otherwise works in the same way as InstrumentHandler.
 func InstrumentHandlerFunc(handlerName string, handlerFunc func(http.ResponseWriter, *http.Request)) http.HandlerFunc {
 	return InstrumentHandlerFuncWithOpts(
 		SummaryOpts{
@@ -195,13 +73,13 @@ func InstrumentHandlerFunc(handlerName string, handlerFunc func(http.ResponseWri
 	)
 }
 
-// InstrumentHandlerWithOpts works like InstrumentHandler (and shares the same
-// issues) but provides more flexibility (at the cost of a more complex call
-// syntax). As InstrumentHandler, this function registers four metric
-// collectors, but it uses the provided SummaryOpts to create them. However, the
-// fields "Name" and "Help" in the SummaryOpts are ignored. "Name" is replaced
-// by "requests_total", "request_duration_microseconds", "request_size_bytes",
-// and "response_size_bytes", respectively. "Help" is replaced by an appropriate
+// InstrumentHandlerWithOpts works like InstrumentHandler but provides more
+// flexibility (at the cost of a more complex call syntax). As
+// InstrumentHandler, this function registers four metric collectors, but it
+// uses the provided SummaryOpts to create them. However, the fields "Name" and
+// "Help" in the SummaryOpts are ignored. "Name" is replaced by
+// "requests_total", "request_duration_microseconds", "request_size_bytes", and
+// "response_size_bytes", respectively. "Help" is replaced by an appropriate
 // help string. The names of the variable labels of the http_requests_total
 // CounterVec are "method" (get, post, etc.), and "code" (HTTP status code).
 //
@@ -220,20 +98,13 @@ func InstrumentHandlerFunc(handlerName string, handlerFunc func(http.ResponseWri
 // cannot use SummaryOpts. Instead, a CounterOpts struct is created internally,
 // and all its fields are set to the equally named fields in the provided
 // SummaryOpts.
-//
-// Deprecated: InstrumentHandlerWithOpts is deprecated for the same reasons as
-// InstrumentHandler is.
 func InstrumentHandlerWithOpts(opts SummaryOpts, handler http.Handler) http.HandlerFunc {
 	return InstrumentHandlerFuncWithOpts(opts, handler.ServeHTTP)
 }
 
-// InstrumentHandlerFuncWithOpts works like InstrumentHandlerFunc (and shares
-// the same issues) but provides more flexibility (at the cost of a more complex
-// call syntax). See InstrumentHandlerWithOpts for details how the provided
-// SummaryOpts are used.
-//
-// Deprecated: InstrumentHandlerFuncWithOpts is deprecated for the same reasons
-// as InstrumentHandler is.
+// InstrumentHandlerFuncWithOpts works like InstrumentHandlerFunc but provides
+// more flexibility (at the cost of a more complex call syntax). See
+// InstrumentHandlerWithOpts for details how the provided SummaryOpts are used.
 func InstrumentHandlerFuncWithOpts(opts SummaryOpts, handlerFunc func(http.ResponseWriter, *http.Request)) http.HandlerFunc {
 	reqCnt := NewCounterVec(
 		CounterOpts{
@@ -267,7 +138,12 @@ func InstrumentHandlerFuncWithOpts(opts SummaryOpts, handlerFunc func(http.Respo
 		now := time.Now()
 
 		delegate := &responseWriterDelegator{ResponseWriter: w}
-		out := computeApproximateRequestSize(r)
+		out := make(chan int)
+		urlLen := 0
+		if r.URL != nil {
+			urlLen = len(r.URL.String())
+		}
+		go computeApproximateRequestSize(r, out, urlLen)
 
 		_, cn := w.(http.CloseNotifier)
 		_, fl := w.(http.Flusher)
@@ -292,37 +168,23 @@ 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.
-	// HandlerFunc that runs in parallel may modify the URL.
-	s := 0
-	if r.URL != nil {
-		s += len(r.URL.String())
+func computeApproximateRequestSize(r *http.Request, out chan int, s int) {
+	s += len(r.Method)
+	s += len(r.Proto)
+	for name, values := range r.Header {
+		s += len(name)
+		for _, value := range values {
+			s += len(value)
+		}
 	}
+	s += len(r.Host)
 
-	out := make(chan int, 1)
+	// N.B. r.Form and r.MultipartForm are assumed to be included in r.URL.
 
-	go func() {
-		s += len(r.Method)
-		s += len(r.Proto)
-		for name, values := range r.Header {
-			s += len(name)
-			for _, value := range values {
-				s += len(value)
-			}
-		}
-		s += len(r.Host)
-
-		// N.B. r.Form and r.MultipartForm are assumed to be included in r.URL.
-
-		if r.ContentLength != -1 {
-			s += int(r.ContentLength)
-		}
-		out <- s
-		close(out)
-	}()
-
-	return out
+	if r.ContentLength != -1 {
+		s += int(r.ContentLength)
+	}
+	out <- s
 }
 
 type responseWriterDelegator struct {

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

@@ -19,11 +19,11 @@ import (
 	dto "github.com/prometheus/client_model/go"
 )
 
-const separatorByte byte = 255
-
 // A Metric models a single sample value with its meta data being exported to
-// Prometheus. Implementations of Metric in this package are Gauge, Counter,
-// Histogram, Summary, and Untyped.
+// Prometheus. Implementers of Metric in this package inclued Gauge, Counter,
+// Untyped, and Summary. Users can implement their own Metric types, but that
+// should be rarely needed. See the example for SelfCollector, which is also an
+// example for a user-implemented Metric.
 type Metric interface {
 	// Desc returns the descriptor for the Metric. This method idempotently
 	// returns the same descriptor throughout the lifetime of the
@@ -34,23 +34,21 @@ type Metric interface {
 	// Write encodes the Metric into a "Metric" Protocol Buffer data
 	// transmission object.
 	//
-	// Metric implementations must observe concurrency safety as reads of
-	// this metric may occur at any time, and any blocking occurs at the
-	// expense of total performance of rendering all registered
-	// metrics. Ideally, Metric implementations should support concurrent
-	// readers.
+	// Implementers of custom Metric types must observe concurrency safety
+	// as reads of this metric may occur at any time, and any blocking
+	// occurs at the expense of total performance of rendering all
+	// registered metrics. Ideally Metric implementations should support
+	// concurrent readers.
 	//
-	// 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
-	// LabelPairSorter useful for that.) Callers of Write should still make
-	// sure of sorting if they depend on it.
+	// The Prometheus client library attempts to minimize memory allocations
+	// and will provide a pre-existing reset dto.Metric pointer. Prometheus
+	// may recycle the dto.Metric proto message, so Metric implementations
+	// should just populate the provided dto.Metric and then should not keep
+	// any reference to it.
+	//
+	// While populating dto.Metric, labels must be sorted lexicographically.
+	// (Implementers may find LabelPairSorter useful for that.)
 	Write(*dto.Metric) error
-	// TODO(beorn7): The original rationale of passing in a pre-allocated
-	// dto.Metric protobuf to save allocations has disappeared. The
-	// signature of this method should be changed to "Write() (*dto.Metric,
-	// error)".
 }
 
 // Opts bundles the options for creating most Metric types. Each metric

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

@@ -28,7 +28,7 @@ type processCollector struct {
 // NewProcessCollector returns a collector which exports the current state of
 // process metrics including cpu, memory and file descriptor usage as well as
 // the process start time for the given process id under the given namespace.
-func NewProcessCollector(pid int, namespace string) Collector {
+func NewProcessCollector(pid int, namespace string) *processCollector {
 	return NewProcessCollectorPIDFn(
 		func() (int, error) { return pid, nil },
 		namespace,
@@ -43,7 +43,7 @@ func NewProcessCollector(pid int, namespace string) Collector {
 func NewProcessCollectorPIDFn(
 	pidFn func() (int, error),
 	namespace string,
-) Collector {
+) *processCollector {
 	c := processCollector{
 		pidFn:     pidFn,
 		collectFn: func(chan<- Metric) {},

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

@@ -0,0 +1,65 @@
+// Copyright 2015 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.
+
+// Copyright (c) 2013, The Prometheus Authors
+// All rights reserved.
+//
+// Use of this source code is governed by a BSD-style license that can be found
+// in the LICENSE file.
+
+package prometheus
+
+// Push triggers a metric collection by the default registry and pushes all
+// collected metrics to the Pushgateway specified by addr. See the Pushgateway
+// documentation for detailed implications of the job and instance
+// parameter. instance can be left empty. You can use just host:port or ip:port
+// as url, in which case 'http://' is added automatically. You can also include
+// the schema in the URL. However, do not include the '/metrics/jobs/...' part.
+//
+// Note that all previously pushed metrics with the same job and instance will
+// be replaced with the metrics pushed by this call. (It uses HTTP method 'PUT'
+// to push to the Pushgateway.)
+func Push(job, instance, url string) error {
+	return defRegistry.Push(job, instance, url, "PUT")
+}
+
+// PushAdd works like Push, but only previously pushed metrics with the same
+// name (and the same job and instance) will be replaced. (It uses HTTP method
+// 'POST' to push to the Pushgateway.)
+func PushAdd(job, instance, url string) error {
+	return defRegistry.Push(job, instance, url, "POST")
+}
+
+// PushCollectors works like Push, but it does not collect from the default
+// registry. Instead, it collects from the provided collectors. It is a
+// convenient way to push only a few metrics.
+func PushCollectors(job, instance, url string, collectors ...Collector) error {
+	return pushCollectors(job, instance, url, "PUT", collectors...)
+}
+
+// PushAddCollectors works like PushAdd, but it does not collect from the
+// default registry. Instead, it collects from the provided collectors. It is a
+// convenient way to push only a few metrics.
+func PushAddCollectors(job, instance, url string, collectors ...Collector) error {
+	return pushCollectors(job, instance, url, "POST", collectors...)
+}
+
+func pushCollectors(job, instance, url, method string, collectors ...Collector) error {
+	r := newRegistry()
+	for _, collector := range collectors {
+		if _, err := r.Register(collector); err != nil {
+			return err
+		}
+	}
+	return r.Push(job, instance, url, method)
+}

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

@@ -15,6 +15,7 @@ package prometheus
 
 import (
 	"fmt"
+	"hash/fnv"
 	"math"
 	"sort"
 	"sync"
@@ -24,11 +25,9 @@ import (
 	"github.com/golang/protobuf/proto"
 
 	dto "github.com/prometheus/client_model/go"
-)
 
-// quantileLabel is used for the label that defines the quantile in a
-// summary.
-const quantileLabel = "quantile"
+	"github.com/prometheus/client_golang/model"
+)
 
 // A Summary captures individual observations from an event or sample stream and
 // summarizes them in a manner similar to traditional summary statistics: 1. sum
@@ -53,12 +52,12 @@ type Summary interface {
 	Observe(float64)
 }
 
-// DefObjectives are the default Summary quantile values.
 var (
+	// DefObjectives are the default Summary quantile values.
 	DefObjectives = map[float64]float64{0.5: 0.05, 0.9: 0.01, 0.99: 0.001}
 
 	errQuantileLabelNotAllowed = fmt.Errorf(
-		"%q is not allowed as label name in summaries", quantileLabel,
+		"%q is not allowed as label name in summaries", model.QuantileLabel,
 	)
 )
 
@@ -113,9 +112,7 @@ type SummaryOpts struct {
 	ConstLabels Labels
 
 	// Objectives defines the quantile rank estimates with their respective
-	// absolute error. If Objectives[q] = e, then the value reported
-	// for q will be the φ-quantile value for some φ between q-e and q+e.
-	// The default value is DefObjectives.
+	// absolute error. The default value is DefObjectives.
 	Objectives map[float64]float64
 
 	// MaxAge defines the duration for which an observation stays relevant
@@ -139,11 +136,11 @@ type SummaryOpts struct {
 	BufCap uint32
 }
 
-// Great fuck-up with the sliding-window decay algorithm... The Merge method of
-// perk/quantile is actually not working as advertised - and it might be
-// unfixable, as the underlying algorithm is apparently not capable of merging
-// summaries in the first place. To avoid using Merge, we are currently adding
-// observations to _each_ age bucket, i.e. the effort to add a sample is
+// TODO: Great fuck-up with the sliding-window decay algorithm... The Merge
+// method of perk/quantile is actually not working as advertised - and it might
+// be unfixable, as the underlying algorithm is apparently not capable of
+// merging summaries in the first place. To avoid using Merge, we are currently
+// adding observations to _each_ age bucket, i.e. the effort to add a sample is
 // essentially multiplied by the number of age buckets. When rotating age
 // buckets, we empty the previous head stream. On scrape time, we simply take
 // the quantiles from the head stream (no merging required). Result: More effort
@@ -173,12 +170,12 @@ func newSummary(desc *Desc, opts SummaryOpts, labelValues ...string) Summary {
 	}
 
 	for _, n := range desc.variableLabels {
-		if n == quantileLabel {
+		if n == model.QuantileLabel {
 			panic(errQuantileLabelNotAllowed)
 		}
 	}
 	for _, lp := range desc.constLabelPairs {
-		if lp.GetName() == quantileLabel {
+		if lp.GetName() == model.QuantileLabel {
 			panic(errQuantileLabelNotAllowed)
 		}
 	}
@@ -227,12 +224,12 @@ func newSummary(desc *Desc, opts SummaryOpts, labelValues ...string) Summary {
 	}
 	sort.Float64s(s.sortedObjectives)
 
-	s.init(s) // Init self-collection.
+	s.Init(s) // Init self-collection.
 	return s
 }
 
 type summary struct {
-	selfCollector
+	SelfCollector
 
 	bufMtx sync.Mutex // Protects hotBuf and hotBufExpTime.
 	mtx    sync.Mutex // Protects every other moving part.
@@ -390,7 +387,7 @@ func (s quantSort) Less(i, j int) bool {
 // (e.g. HTTP request latencies, partitioned by status code and method). Create
 // instances with NewSummaryVec.
 type SummaryVec struct {
-	*MetricVec
+	MetricVec
 }
 
 // NewSummaryVec creates a new SummaryVec based on the provided SummaryOpts and
@@ -404,9 +401,14 @@ func NewSummaryVec(opts SummaryOpts, labelNames []string) *SummaryVec {
 		opts.ConstLabels,
 	)
 	return &SummaryVec{
-		MetricVec: newMetricVec(desc, func(lvs ...string) Metric {
-			return newSummary(desc, opts, lvs...)
-		}),
+		MetricVec: MetricVec{
+			children: map[uint64]Metric{},
+			desc:     desc,
+			hash:     fnv.New64a(),
+			newMetric: func(lvs ...string) Metric {
+				return newSummary(desc, opts, lvs...)
+			},
+		},
 	}
 }
 

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

@@ -13,6 +13,8 @@
 
 package prometheus
 
+import "hash/fnv"
+
 // Untyped is a Metric that represents a single numerical value that can
 // arbitrarily go up and down.
 //
@@ -56,7 +58,7 @@ func NewUntyped(opts UntypedOpts) Untyped {
 // labels. This is used if you want to count the same thing partitioned by
 // various dimensions. Create instances with NewUntypedVec.
 type UntypedVec struct {
-	*MetricVec
+	MetricVec
 }
 
 // NewUntypedVec creates a new UntypedVec based on the provided UntypedOpts and
@@ -70,9 +72,14 @@ func NewUntypedVec(opts UntypedOpts, labelNames []string) *UntypedVec {
 		opts.ConstLabels,
 	)
 	return &UntypedVec{
-		MetricVec: newMetricVec(desc, func(lvs ...string) Metric {
-			return newValue(desc, UntypedValue, 0, lvs...)
-		}),
+		MetricVec: MetricVec{
+			children: map[uint64]Metric{},
+			desc:     desc,
+			hash:     fnv.New64a(),
+			newMetric: func(lvs ...string) Metric {
+				return newValue(desc, UntypedValue, 0, lvs...)
+			},
+		},
 	}
 }
 

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

@@ -48,7 +48,7 @@ type value struct {
 	// operations.  http://golang.org/pkg/sync/atomic/#pkg-note-BUG
 	valBits uint64
 
-	selfCollector
+	SelfCollector
 
 	desc       *Desc
 	valType    ValueType
@@ -68,7 +68,7 @@ func newValue(desc *Desc, valueType ValueType, val float64, labelValues ...strin
 		valBits:    math.Float64bits(val),
 		labelPairs: makeLabelPairs(desc, labelValues),
 	}
-	result.init(result)
+	result.Init(result)
 	return result
 }
 
@@ -113,7 +113,7 @@ func (v *value) Write(out *dto.Metric) error {
 // library to back the implementations of CounterFunc, GaugeFunc, and
 // UntypedFunc.
 type valueFunc struct {
-	selfCollector
+	SelfCollector
 
 	desc       *Desc
 	valType    ValueType
@@ -134,7 +134,7 @@ func newValueFunc(desc *Desc, valueType ValueType, function func() float64) *val
 		function:   function,
 		labelPairs: makeLabelPairs(desc, nil),
 	}
-	result.init(result)
+	result.Init(result)
 	return result
 }
 

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

@@ -14,10 +14,10 @@
 package prometheus
 
 import (
+	"bytes"
 	"fmt"
+	"hash"
 	"sync"
-
-	"github.com/prometheus/common/model"
 )
 
 // MetricVec is a Collector to bundle metrics of the same name that
@@ -26,32 +26,17 @@ import (
 // type. GaugeVec, CounterVec, SummaryVec, and UntypedVec are examples already
 // provided in this package.
 type MetricVec struct {
-	mtx      sync.RWMutex // Protects the children.
-	children map[uint64][]metricWithLabelValues
+	mtx      sync.RWMutex // Protects not only children, but also hash and buf.
+	children map[uint64]Metric
 	desc     *Desc
 
-	newMetric   func(labelValues ...string) Metric
-	hashAdd     func(h uint64, s string) uint64 // replace hash function for testing collision handling
-	hashAddByte func(h uint64, b byte) uint64
-}
+	// hash is our own hash instance to avoid repeated allocations.
+	hash hash.Hash64
+	// buf is used to copy string contents into it for hashing,
+	// again to avoid allocations.
+	buf bytes.Buffer
 
-// newMetricVec returns an initialized MetricVec. The concrete value is
-// returned for embedding into another struct.
-func newMetricVec(desc *Desc, newMetric func(lvs ...string) Metric) *MetricVec {
-	return &MetricVec{
-		children:    map[uint64][]metricWithLabelValues{},
-		desc:        desc,
-		newMetric:   newMetric,
-		hashAdd:     hashAdd,
-		hashAddByte: hashAddByte,
-	}
-}
-
-// metricWithLabelValues provides the metric and its label values for
-// disambiguation on hash collision.
-type metricWithLabelValues struct {
-	values []string
-	metric Metric
+	newMetric func(labelValues ...string) Metric
 }
 
 // Describe implements Collector. The length of the returned slice
@@ -65,10 +50,8 @@ func (m *MetricVec) Collect(ch chan<- Metric) {
 	m.mtx.RLock()
 	defer m.mtx.RUnlock()
 
-	for _, metrics := range m.children {
-		for _, metric := range metrics {
-			ch <- metric.metric
-		}
+	for _, metric := range m.children {
+		ch <- metric
 	}
 }
 
@@ -97,12 +80,14 @@ func (m *MetricVec) Collect(ch chan<- Metric) {
 // with a performance overhead (for creating and processing the Labels map).
 // See also the GaugeVec example.
 func (m *MetricVec) GetMetricWithLabelValues(lvs ...string) (Metric, error) {
+	m.mtx.Lock()
+	defer m.mtx.Unlock()
+
 	h, err := m.hashLabelValues(lvs)
 	if err != nil {
 		return nil, err
 	}
-
-	return m.getOrCreateMetricWithLabelValues(h, lvs), nil
+	return m.getOrCreateMetric(h, lvs...), nil
 }
 
 // GetMetricWith returns the Metric for the given Labels map (the label names
@@ -118,12 +103,18 @@ func (m *MetricVec) GetMetricWithLabelValues(lvs ...string) (Metric, error) {
 // GetMetricWithLabelValues(...string). See there for pros and cons of the two
 // methods.
 func (m *MetricVec) GetMetricWith(labels Labels) (Metric, error) {
+	m.mtx.Lock()
+	defer m.mtx.Unlock()
+
 	h, err := m.hashLabels(labels)
 	if err != nil {
 		return nil, err
 	}
-
-	return m.getOrCreateMetricWithLabels(h, labels), nil
+	lvs := make([]string, len(labels))
+	for i, label := range m.desc.variableLabels {
+		lvs[i] = labels[label]
+	}
+	return m.getOrCreateMetric(h, lvs...), nil
 }
 
 // WithLabelValues works as GetMetricWithLabelValues, but panics if an error
@@ -171,7 +162,11 @@ func (m *MetricVec) DeleteLabelValues(lvs ...string) bool {
 	if err != nil {
 		return false
 	}
-	return m.deleteByHashWithLabelValues(h, lvs)
+	if _, has := m.children[h]; !has {
+		return false
+	}
+	delete(m.children, h)
+	return true
 }
 
 // Delete deletes the metric where the variable labels are the same as those
@@ -192,50 +187,10 @@ func (m *MetricVec) Delete(labels Labels) bool {
 	if err != nil {
 		return false
 	}
-
-	return m.deleteByHashWithLabels(h, labels)
-}
-
-// deleteByHashWithLabelValues removes the metric from the hash bucket h. If
-// there are multiple matches in the bucket, use lvs to select a metric and
-// remove only that metric.
-func (m *MetricVec) deleteByHashWithLabelValues(h uint64, lvs []string) bool {
-	metrics, ok := m.children[h]
-	if !ok {
+	if _, has := m.children[h]; !has {
 		return false
 	}
-
-	i := m.findMetricWithLabelValues(metrics, lvs)
-	if i >= len(metrics) {
-		return false
-	}
-
-	if len(metrics) > 1 {
-		m.children[h] = append(metrics[:i], metrics[i+1:]...)
-	} else {
-		delete(m.children, h)
-	}
-	return true
-}
-
-// deleteByHashWithLabels removes the metric from the hash bucket h. If there
-// are multiple matches in the bucket, use lvs to select a metric and remove
-// only that metric.
-func (m *MetricVec) deleteByHashWithLabels(h uint64, labels Labels) bool {
-	metrics, ok := m.children[h]
-	if !ok {
-		return false
-	}
-	i := m.findMetricWithLabels(metrics, labels)
-	if i >= len(metrics) {
-		return false
-	}
-
-	if len(metrics) > 1 {
-		m.children[h] = append(metrics[:i], metrics[i+1:]...)
-	} else {
-		delete(m.children, h)
-	}
+	delete(m.children, h)
 	return true
 }
 
@@ -253,152 +208,40 @@ func (m *MetricVec) hashLabelValues(vals []string) (uint64, error) {
 	if len(vals) != len(m.desc.variableLabels) {
 		return 0, errInconsistentCardinality
 	}
-	h := hashNew()
+	m.hash.Reset()
 	for _, val := range vals {
-		h = m.hashAdd(h, val)
-		h = m.hashAddByte(h, model.SeparatorByte)
+		m.buf.Reset()
+		m.buf.WriteString(val)
+		m.hash.Write(m.buf.Bytes())
 	}
-	return h, nil
+	return m.hash.Sum64(), nil
 }
 
 func (m *MetricVec) hashLabels(labels Labels) (uint64, error) {
 	if len(labels) != len(m.desc.variableLabels) {
 		return 0, errInconsistentCardinality
 	}
-	h := hashNew()
+	m.hash.Reset()
 	for _, label := range m.desc.variableLabels {
 		val, ok := labels[label]
 		if !ok {
 			return 0, fmt.Errorf("label name %q missing in label map", label)
 		}
-		h = m.hashAdd(h, val)
-		h = m.hashAddByte(h, model.SeparatorByte)
+		m.buf.Reset()
+		m.buf.WriteString(val)
+		m.hash.Write(m.buf.Bytes())
 	}
-	return h, nil
+	return m.hash.Sum64(), nil
 }
 
-// getOrCreateMetricWithLabelValues retrieves the metric by hash and label value
-// or creates it and returns the new one.
-//
-// This function holds the mutex.
-func (m *MetricVec) getOrCreateMetricWithLabelValues(hash uint64, lvs []string) Metric {
-	m.mtx.RLock()
-	metric, ok := m.getMetricWithLabelValues(hash, lvs)
-	m.mtx.RUnlock()
-	if ok {
-		return metric
-	}
-
-	m.mtx.Lock()
-	defer m.mtx.Unlock()
-	metric, ok = m.getMetricWithLabelValues(hash, lvs)
+func (m *MetricVec) getOrCreateMetric(hash uint64, labelValues ...string) Metric {
+	metric, ok := m.children[hash]
 	if !ok {
-		// Copy to avoid allocation in case wo don't go down this code path.
-		copiedLVs := make([]string, len(lvs))
-		copy(copiedLVs, lvs)
-		metric = m.newMetric(copiedLVs...)
-		m.children[hash] = append(m.children[hash], metricWithLabelValues{values: copiedLVs, metric: metric})
+		// Copy labelValues. Otherwise, they would be allocated even if we don't go
+		// down this code path.
+		copiedLabelValues := append(make([]string, 0, len(labelValues)), labelValues...)
+		metric = m.newMetric(copiedLabelValues...)
+		m.children[hash] = metric
 	}
 	return metric
 }
-
-// getOrCreateMetricWithLabelValues retrieves the metric by hash and label value
-// or creates it and returns the new one.
-//
-// This function holds the mutex.
-func (m *MetricVec) getOrCreateMetricWithLabels(hash uint64, labels Labels) Metric {
-	m.mtx.RLock()
-	metric, ok := m.getMetricWithLabels(hash, labels)
-	m.mtx.RUnlock()
-	if ok {
-		return metric
-	}
-
-	m.mtx.Lock()
-	defer m.mtx.Unlock()
-	metric, ok = m.getMetricWithLabels(hash, labels)
-	if !ok {
-		lvs := m.extractLabelValues(labels)
-		metric = m.newMetric(lvs...)
-		m.children[hash] = append(m.children[hash], metricWithLabelValues{values: lvs, metric: metric})
-	}
-	return metric
-}
-
-// getMetricWithLabelValues gets a metric while handling possible collisions in
-// the hash space. Must be called while holding read mutex.
-func (m *MetricVec) getMetricWithLabelValues(h uint64, lvs []string) (Metric, bool) {
-	metrics, ok := m.children[h]
-	if ok {
-		if i := m.findMetricWithLabelValues(metrics, lvs); i < len(metrics) {
-			return metrics[i].metric, true
-		}
-	}
-	return nil, false
-}
-
-// getMetricWithLabels gets a metric while handling possible collisions in
-// the hash space. Must be called while holding read mutex.
-func (m *MetricVec) getMetricWithLabels(h uint64, labels Labels) (Metric, bool) {
-	metrics, ok := m.children[h]
-	if ok {
-		if i := m.findMetricWithLabels(metrics, labels); i < len(metrics) {
-			return metrics[i].metric, true
-		}
-	}
-	return nil, false
-}
-
-// findMetricWithLabelValues returns the index of the matching metric or
-// len(metrics) if not found.
-func (m *MetricVec) findMetricWithLabelValues(metrics []metricWithLabelValues, lvs []string) int {
-	for i, metric := range metrics {
-		if m.matchLabelValues(metric.values, lvs) {
-			return i
-		}
-	}
-	return len(metrics)
-}
-
-// findMetricWithLabels returns the index of the matching metric or len(metrics)
-// if not found.
-func (m *MetricVec) findMetricWithLabels(metrics []metricWithLabelValues, labels Labels) int {
-	for i, metric := range metrics {
-		if m.matchLabels(metric.values, labels) {
-			return i
-		}
-	}
-	return len(metrics)
-}
-
-func (m *MetricVec) matchLabelValues(values []string, lvs []string) bool {
-	if len(values) != len(lvs) {
-		return false
-	}
-	for i, v := range values {
-		if v != lvs[i] {
-			return false
-		}
-	}
-	return true
-}
-
-func (m *MetricVec) matchLabels(values []string, labels Labels) bool {
-	if len(labels) != len(values) {
-		return false
-	}
-	for i, k := range m.desc.variableLabels {
-		if values[i] != labels[k] {
-			return false
-		}
-	}
-	return true
-}
-
-func (m *MetricVec) extractLabelValues(labels Labels) []string {
-	labelValues := make([]string, len(labels))
-	for i, k := range m.desc.variableLabels {
-		labelValues[i] = labels[k]
-	}
-	return labelValues
-}

vendor/github.com/prometheus/client_golang/text/create.go

@@ -0,0 +1,315 @@
+// Copyright 2014 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 text contains helper functions to parse and create text-based
+// exchange formats. The package currently supports (only) version 0.0.4 of the
+// exchange format. Should other versions be supported in the future, some
+// versioning scheme has to be applied. Possibilities include separate packages
+// or separate functions. The best way depends on the nature of future changes,
+// which is the reason why no versioning scheme has been applied prematurely
+// here.
+package text
+
+import (
+	"bytes"
+	"fmt"
+	"io"
+	"math"
+	"strings"
+
+	"github.com/prometheus/client_golang/model"
+	dto "github.com/prometheus/client_model/go"
+)
+
+// MetricFamilyToText converts a MetricFamily proto message into text format and
+// writes the resulting lines to 'out'. It returns the number of bytes written
+// and any error encountered.  This function does not perform checks on the
+// content of the metric and label names, i.e. invalid metric or label names
+// will result in invalid text format output.
+// This method fulfills the type 'prometheus.encoder'.
+func MetricFamilyToText(out io.Writer, in *dto.MetricFamily) (int, error) {
+	var written int
+
+	// Fail-fast checks.
+	if len(in.Metric) == 0 {
+		return written, fmt.Errorf("MetricFamily has no metrics: %s", in)
+	}
+	name := in.GetName()
+	if name == "" {
+		return written, fmt.Errorf("MetricFamily has no name: %s", in)
+	}
+	if in.Type == nil {
+		return written, fmt.Errorf("MetricFamily has no type: %s", in)
+	}
+
+	// Comments, first HELP, then TYPE.
+	if in.Help != nil {
+		n, err := fmt.Fprintf(
+			out, "# HELP %s %s\n",
+			name, escapeString(*in.Help, false),
+		)
+		written += n
+		if err != nil {
+			return written, err
+		}
+	}
+	metricType := in.GetType()
+	n, err := fmt.Fprintf(
+		out, "# TYPE %s %s\n",
+		name, strings.ToLower(metricType.String()),
+	)
+	written += n
+	if err != nil {
+		return written, err
+	}
+
+	// Finally the samples, one line for each.
+	for _, metric := range in.Metric {
+		switch metricType {
+		case dto.MetricType_COUNTER:
+			if metric.Counter == nil {
+				return written, fmt.Errorf(
+					"expected counter in metric %s %s", name, metric,
+				)
+			}
+			n, err = writeSample(
+				name, metric, "", "",
+				metric.Counter.GetValue(),
+				out,
+			)
+		case dto.MetricType_GAUGE:
+			if metric.Gauge == nil {
+				return written, fmt.Errorf(
+					"expected gauge in metric %s %s", name, metric,
+				)
+			}
+			n, err = writeSample(
+				name, metric, "", "",
+				metric.Gauge.GetValue(),
+				out,
+			)
+		case dto.MetricType_UNTYPED:
+			if metric.Untyped == nil {
+				return written, fmt.Errorf(
+					"expected untyped in metric %s %s", name, metric,
+				)
+			}
+			n, err = writeSample(
+				name, metric, "", "",
+				metric.Untyped.GetValue(),
+				out,
+			)
+		case dto.MetricType_SUMMARY:
+			if metric.Summary == nil {
+				return written, fmt.Errorf(
+					"expected summary in metric %s %s", name, metric,
+				)
+			}
+			for _, q := range metric.Summary.Quantile {
+				n, err = writeSample(
+					name, metric,
+					model.QuantileLabel, fmt.Sprint(q.GetQuantile()),
+					q.GetValue(),
+					out,
+				)
+				written += n
+				if err != nil {
+					return written, err
+				}
+			}
+			n, err = writeSample(
+				name+"_sum", metric, "", "",
+				metric.Summary.GetSampleSum(),
+				out,
+			)
+			if err != nil {
+				return written, err
+			}
+			written += n
+			n, err = writeSample(
+				name+"_count", metric, "", "",
+				float64(metric.Summary.GetSampleCount()),
+				out,
+			)
+		case dto.MetricType_HISTOGRAM:
+			if metric.Histogram == nil {
+				return written, fmt.Errorf(
+					"expected histogram in metric %s %s", name, metric,
+				)
+			}
+			infSeen := false
+			for _, q := range metric.Histogram.Bucket {
+				n, err = writeSample(
+					name+"_bucket", metric,
+					model.BucketLabel, fmt.Sprint(q.GetUpperBound()),
+					float64(q.GetCumulativeCount()),
+					out,
+				)
+				written += n
+				if err != nil {
+					return written, err
+				}
+				if math.IsInf(q.GetUpperBound(), +1) {
+					infSeen = true
+				}
+			}
+			if !infSeen {
+				n, err = writeSample(
+					name+"_bucket", metric,
+					model.BucketLabel, "+Inf",
+					float64(metric.Histogram.GetSampleCount()),
+					out,
+				)
+				if err != nil {
+					return written, err
+				}
+				written += n
+			}
+			n, err = writeSample(
+				name+"_sum", metric, "", "",
+				metric.Histogram.GetSampleSum(),
+				out,
+			)
+			if err != nil {
+				return written, err
+			}
+			written += n
+			n, err = writeSample(
+				name+"_count", metric, "", "",
+				float64(metric.Histogram.GetSampleCount()),
+				out,
+			)
+		default:
+			return written, fmt.Errorf(
+				"unexpected type in metric %s %s", name, metric,
+			)
+		}
+		written += n
+		if err != nil {
+			return written, err
+		}
+	}
+	return written, nil
+}
+
+// writeSample writes a single sample in text format to out, given the metric
+// name, the metric proto message itself, optionally an additional label name
+// and value (use empty strings if not required), and the value. The function
+// returns the number of bytes written and any error encountered.
+func writeSample(
+	name string,
+	metric *dto.Metric,
+	additionalLabelName, additionalLabelValue string,
+	value float64,
+	out io.Writer,
+) (int, error) {
+	var written int
+	n, err := fmt.Fprint(out, name)
+	written += n
+	if err != nil {
+		return written, err
+	}
+	n, err = labelPairsToText(
+		metric.Label,
+		additionalLabelName, additionalLabelValue,
+		out,
+	)
+	written += n
+	if err != nil {
+		return written, err
+	}
+	n, err = fmt.Fprintf(out, " %v", value)
+	written += n
+	if err != nil {
+		return written, err
+	}
+	if metric.TimestampMs != nil {
+		n, err = fmt.Fprintf(out, " %v", *metric.TimestampMs)
+		written += n
+		if err != nil {
+			return written, err
+		}
+	}
+	n, err = out.Write([]byte{'\n'})
+	written += n
+	if err != nil {
+		return written, err
+	}
+	return written, nil
+}
+
+// labelPairsToText converts a slice of LabelPair proto messages plus the
+// explicitly given additional label pair into text formatted as required by the
+// text format and writes it to 'out'. An empty slice in combination with an
+// empty string 'additionalLabelName' results in nothing being
+// written. Otherwise, the label pairs are written, escaped as required by the
+// text format, and enclosed in '{...}'. The function returns the number of
+// bytes written and any error encountered.
+func labelPairsToText(
+	in []*dto.LabelPair,
+	additionalLabelName, additionalLabelValue string,
+	out io.Writer,
+) (int, error) {
+	if len(in) == 0 && additionalLabelName == "" {
+		return 0, nil
+	}
+	var written int
+	separator := '{'
+	for _, lp := range in {
+		n, err := fmt.Fprintf(
+			out, `%c%s="%s"`,
+			separator, lp.GetName(), escapeString(lp.GetValue(), true),
+		)
+		written += n
+		if err != nil {
+			return written, err
+		}
+		separator = ','
+	}
+	if additionalLabelName != "" {
+		n, err := fmt.Fprintf(
+			out, `%c%s="%s"`,
+			separator, additionalLabelName,
+			escapeString(additionalLabelValue, true),
+		)
+		written += n
+		if err != nil {
+			return written, err
+		}
+	}
+	n, err := out.Write([]byte{'}'})
+	written += n
+	if err != nil {
+		return written, err
+	}
+	return written, nil
+}
+
+// escapeString replaces '\' by '\\', new line character by '\n', and - if
+// includeDoubleQuote is true - '"' by '\"'.
+func escapeString(v string, includeDoubleQuote bool) string {
+	result := bytes.NewBuffer(make([]byte, 0, len(v)))
+	for _, c := range v {
+		switch {
+		case c == '\\':
+			result.WriteString(`\\`)
+		case includeDoubleQuote && c == '"':
+			result.WriteString(`\"`)
+		case c == '\n':
+			result.WriteString(`\n`)
+		default:
+			result.WriteRune(c)
+		}
+	}
+	return result.String()
+}

vendor/github.com/prometheus/client_golang/text/parse.go

@@ -0,0 +1,746 @@
+// Copyright 2014 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 text
+
+import (
+	"bufio"
+	"bytes"
+	"fmt"
+	"io"
+	"math"
+	"strconv"
+	"strings"
+
+	dto "github.com/prometheus/client_model/go"
+
+	"github.com/golang/protobuf/proto"
+	"github.com/prometheus/client_golang/model"
+)
+
+// A stateFn is a function that represents a state in a state machine. By
+// executing it, the state is progressed to the next state. The stateFn returns
+// another stateFn, which represents the new state. The end state is represented
+// by nil.
+type stateFn func() stateFn
+
+// ParseError signals errors while parsing the simple and flat text-based
+// exchange format.
+type ParseError struct {
+	Line int
+	Msg  string
+}
+
+// Error implements the error interface.
+func (e ParseError) Error() string {
+	return fmt.Sprintf("text format parsing error in line %d: %s", e.Line, e.Msg)
+}
+
+// Parser is used to parse the simple and flat text-based exchange format. Its
+// nil value is ready to use.
+type Parser struct {
+	metricFamiliesByName map[string]*dto.MetricFamily
+	buf                  *bufio.Reader // Where the parsed input is read through.
+	err                  error         // Most recent error.
+	lineCount            int           // Tracks the line count for error messages.
+	currentByte          byte          // The most recent byte read.
+	currentToken         bytes.Buffer  // Re-used each time a token has to be gathered from multiple bytes.
+	currentMF            *dto.MetricFamily
+	currentMetric        *dto.Metric
+	currentLabelPair     *dto.LabelPair
+
+	// The remaining member variables are only used for summaries/histograms.
+	currentLabels map[string]string // All labels including '__name__' but excluding 'quantile'/'le'
+	// Summary specific.
+	summaries       map[uint64]*dto.Metric // Key is created with LabelsToSignature.
+	currentQuantile float64
+	// Histogram specific.
+	histograms    map[uint64]*dto.Metric // Key is created with LabelsToSignature.
+	currentBucket float64
+	// These tell us if the currently processed line ends on '_count' or
+	// '_sum' respectively and belong to a summary/histogram, representing the sample
+	// count and sum of that summary/histogram.
+	currentIsSummaryCount, currentIsSummarySum     bool
+	currentIsHistogramCount, currentIsHistogramSum bool
+}
+
+// TextToMetricFamilies reads 'in' as the simple and flat text-based exchange
+// format and creates MetricFamily proto messages. It returns the MetricFamily
+// proto messages in a map where the metric names are the keys, along with any
+// error encountered.
+//
+// If the input contains duplicate metrics (i.e. lines with the same metric name
+// and exactly the same label set), the resulting MetricFamily will contain
+// duplicate Metric proto messages. Similar is true for duplicate label
+// names. Checks for duplicates have to be performed separately, if required.
+// Also note that neither the metrics within each MetricFamily are sorted nor
+// the label pairs within each Metric. Sorting is not required for the most
+// frequent use of this method, which is sample ingestion in the Prometheus
+// server. However, for presentation purposes, you might want to sort the
+// metrics, and in some cases, you must sort the labels, e.g. for consumption by
+// the metric family injection hook of the Prometheus registry.
+//
+// Summaries and histograms are rather special beasts. You would probably not
+// use them in the simple text format anyway. This method can deal with
+// summaries and histograms if they are presented in exactly the way the
+// text.Create function creates them.
+//
+// This method must not be called concurrently. If you want to parse different
+// input concurrently, instantiate a separate Parser for each goroutine.
+func (p *Parser) TextToMetricFamilies(in io.Reader) (map[string]*dto.MetricFamily, error) {
+	p.reset(in)
+	for nextState := p.startOfLine; nextState != nil; nextState = nextState() {
+		// Magic happens here...
+	}
+	// Get rid of empty metric families.
+	for k, mf := range p.metricFamiliesByName {
+		if len(mf.GetMetric()) == 0 {
+			delete(p.metricFamiliesByName, k)
+		}
+	}
+	return p.metricFamiliesByName, p.err
+}
+
+func (p *Parser) reset(in io.Reader) {
+	p.metricFamiliesByName = map[string]*dto.MetricFamily{}
+	if p.buf == nil {
+		p.buf = bufio.NewReader(in)
+	} else {
+		p.buf.Reset(in)
+	}
+	p.err = nil
+	p.lineCount = 0
+	if p.summaries == nil || len(p.summaries) > 0 {
+		p.summaries = map[uint64]*dto.Metric{}
+	}
+	if p.histograms == nil || len(p.histograms) > 0 {
+		p.histograms = map[uint64]*dto.Metric{}
+	}
+	p.currentQuantile = math.NaN()
+	p.currentBucket = math.NaN()
+}
+
+// startOfLine represents the state where the next byte read from p.buf is the
+// start of a line (or whitespace leading up to it).
+func (p *Parser) startOfLine() stateFn {
+	p.lineCount++
+	if p.skipBlankTab(); p.err != nil {
+		// End of input reached. This is the only case where
+		// that is not an error but a signal that we are done.
+		p.err = nil
+		return nil
+	}
+	switch p.currentByte {
+	case '#':
+		return p.startComment
+	case '\n':
+		return p.startOfLine // Empty line, start the next one.
+	}
+	return p.readingMetricName
+}
+
+// startComment represents the state where the next byte read from p.buf is the
+// start of a comment (or whitespace leading up to it).
+func (p *Parser) startComment() stateFn {
+	if p.skipBlankTab(); p.err != nil {
+		return nil // Unexpected end of input.
+	}
+	if p.currentByte == '\n' {
+		return p.startOfLine
+	}
+	if p.readTokenUntilWhitespace(); p.err != nil {
+		return nil // Unexpected end of input.
+	}
+	// If we have hit the end of line already, there is nothing left
+	// to do. This is not considered a syntax error.
+	if p.currentByte == '\n' {
+		return p.startOfLine
+	}
+	keyword := p.currentToken.String()
+	if keyword != "HELP" && keyword != "TYPE" {
+		// Generic comment, ignore by fast forwarding to end of line.
+		for p.currentByte != '\n' {
+			if p.currentByte, p.err = p.buf.ReadByte(); p.err != nil {
+				return nil // Unexpected end of input.
+			}
+		}
+		return p.startOfLine
+	}
+	// There is something. Next has to be a metric name.
+	if p.skipBlankTab(); p.err != nil {
+		return nil // Unexpected end of input.
+	}
+	if p.readTokenAsMetricName(); p.err != nil {
+		return nil // Unexpected end of input.
+	}
+	if p.currentByte == '\n' {
+		// At the end of the line already.
+		// Again, this is not considered a syntax error.
+		return p.startOfLine
+	}
+	if !isBlankOrTab(p.currentByte) {
+		p.parseError("invalid metric name in comment")
+		return nil
+	}
+	p.setOrCreateCurrentMF()
+	if p.skipBlankTab(); p.err != nil {
+		return nil // Unexpected end of input.
+	}
+	if p.currentByte == '\n' {
+		// At the end of the line already.
+		// Again, this is not considered a syntax error.
+		return p.startOfLine
+	}
+	switch keyword {
+	case "HELP":
+		return p.readingHelp
+	case "TYPE":
+		return p.readingType
+	}
+	panic(fmt.Sprintf("code error: unexpected keyword %q", keyword))
+}
+
+// readingMetricName represents the state where the last byte read (now in
+// p.currentByte) is the first byte of a metric name.
+func (p *Parser) readingMetricName() stateFn {
+	if p.readTokenAsMetricName(); p.err != nil {
+		return nil
+	}
+	if p.currentToken.Len() == 0 {
+		p.parseError("invalid metric name")
+		return nil
+	}
+	p.setOrCreateCurrentMF()
+	// Now is the time to fix the type if it hasn't happened yet.
+	if p.currentMF.Type == nil {
+		p.currentMF.Type = dto.MetricType_UNTYPED.Enum()
+	}
+	p.currentMetric = &dto.Metric{}
+	// Do not append the newly created currentMetric to
+	// currentMF.Metric right now. First wait if this is a summary,
+	// and the metric exists already, which we can only know after
+	// having read all the labels.
+	if p.skipBlankTabIfCurrentBlankTab(); p.err != nil {
+		return nil // Unexpected end of input.
+	}
+	return p.readingLabels
+}
+
+// readingLabels represents the state where the last byte read (now in
+// p.currentByte) is either the first byte of the label set (i.e. a '{'), or the
+// first byte of the value (otherwise).
+func (p *Parser) readingLabels() stateFn {
+	// Summaries/histograms are special. We have to reset the
+	// currentLabels map, currentQuantile and currentBucket before starting to
+	// read labels.
+	if p.currentMF.GetType() == dto.MetricType_SUMMARY || p.currentMF.GetType() == dto.MetricType_HISTOGRAM {
+		p.currentLabels = map[string]string{}
+		p.currentLabels[string(model.MetricNameLabel)] = p.currentMF.GetName()
+		p.currentQuantile = math.NaN()
+		p.currentBucket = math.NaN()
+	}
+	if p.currentByte != '{' {
+		return p.readingValue
+	}
+	return p.startLabelName
+}
+
+// startLabelName represents the state where the next byte read from p.buf is
+// the start of a label name (or whitespace leading up to it).
+func (p *Parser) startLabelName() stateFn {
+	if p.skipBlankTab(); p.err != nil {
+		return nil // Unexpected end of input.
+	}
+	if p.currentByte == '}' {
+		if p.skipBlankTab(); p.err != nil {
+			return nil // Unexpected end of input.
+		}
+		return p.readingValue
+	}
+	if p.readTokenAsLabelName(); p.err != nil {
+		return nil // Unexpected end of input.
+	}
+	if p.currentToken.Len() == 0 {
+		p.parseError(fmt.Sprintf("invalid label name for metric %q", p.currentMF.GetName()))
+		return nil
+	}
+	p.currentLabelPair = &dto.LabelPair{Name: proto.String(p.currentToken.String())}
+	if p.currentLabelPair.GetName() == string(model.MetricNameLabel) {
+		p.parseError(fmt.Sprintf("label name %q is reserved", model.MetricNameLabel))
+		return nil
+	}
+	// Special summary/histogram treatment. Don't add 'quantile' and 'le'
+	// labels to 'real' labels.
+	if !(p.currentMF.GetType() == dto.MetricType_SUMMARY && p.currentLabelPair.GetName() == model.QuantileLabel) &&
+		!(p.currentMF.GetType() == dto.MetricType_HISTOGRAM && p.currentLabelPair.GetName() == model.BucketLabel) {
+		p.currentMetric.Label = append(p.currentMetric.Label, p.currentLabelPair)
+	}
+	if p.skipBlankTabIfCurrentBlankTab(); p.err != nil {
+		return nil // Unexpected end of input.
+	}
+	if p.currentByte != '=' {
+		p.parseError(fmt.Sprintf("expected '=' after label name, found %q", p.currentByte))
+		return nil
+	}
+	return p.startLabelValue
+}
+
+// startLabelValue represents the state where the next byte read from p.buf is
+// the start of a (quoted) label value (or whitespace leading up to it).
+func (p *Parser) startLabelValue() stateFn {
+	if p.skipBlankTab(); p.err != nil {
+		return nil // Unexpected end of input.
+	}
+	if p.currentByte != '"' {
+		p.parseError(fmt.Sprintf("expected '\"' at start of label value, found %q", p.currentByte))
+		return nil
+	}
+	if p.readTokenAsLabelValue(); p.err != nil {
+		return nil
+	}
+	p.currentLabelPair.Value = proto.String(p.currentToken.String())
+	// Special treatment of summaries:
+	// - Quantile labels are special, will result in dto.Quantile later.
+	// - Other labels have to be added to currentLabels for signature calculation.
+	if p.currentMF.GetType() == dto.MetricType_SUMMARY {
+		if p.currentLabelPair.GetName() == model.QuantileLabel {
+			if p.currentQuantile, p.err = strconv.ParseFloat(p.currentLabelPair.GetValue(), 64); p.err != nil {
+				// Create a more helpful error message.
+				p.parseError(fmt.Sprintf("expected float as value for 'quantile' label, got %q", p.currentLabelPair.GetValue()))
+				return nil
+			}
+		} else {
+			p.currentLabels[p.currentLabelPair.GetName()] = p.currentLabelPair.GetValue()
+		}
+	}
+	// Similar special treatment of histograms.
+	if p.currentMF.GetType() == dto.MetricType_HISTOGRAM {
+		if p.currentLabelPair.GetName() == model.BucketLabel {
+			if p.currentBucket, p.err = strconv.ParseFloat(p.currentLabelPair.GetValue(), 64); p.err != nil {
+				// Create a more helpful error message.
+				p.parseError(fmt.Sprintf("expected float as value for 'le' label, got %q", p.currentLabelPair.GetValue()))
+				return nil
+			}
+		} else {
+			p.currentLabels[p.currentLabelPair.GetName()] = p.currentLabelPair.GetValue()
+		}
+	}
+	if p.skipBlankTab(); p.err != nil {
+		return nil // Unexpected end of input.
+	}
+	switch p.currentByte {
+	case ',':
+		return p.startLabelName
+
+	case '}':
+		if p.skipBlankTab(); p.err != nil {
+			return nil // Unexpected end of input.
+		}
+		return p.readingValue
+	default:
+		p.parseError(fmt.Sprintf("unexpected end of label value %q", p.currentLabelPair.Value))
+		return nil
+	}
+}
+
+// readingValue represents the state where the last byte read (now in
+// p.currentByte) is the first byte of the sample value (i.e. a float).
+func (p *Parser) readingValue() stateFn {
+	// When we are here, we have read all the labels, so for the
+	// special case of a summary/histogram, we can finally find out
+	// if the metric already exists.
+	if p.currentMF.GetType() == dto.MetricType_SUMMARY {
+		signature := model.LabelsToSignature(p.currentLabels)
+		if summary := p.summaries[signature]; summary != nil {
+			p.currentMetric = summary
+		} else {
+			p.summaries[signature] = p.currentMetric
+			p.currentMF.Metric = append(p.currentMF.Metric, p.currentMetric)
+		}
+	} else if p.currentMF.GetType() == dto.MetricType_HISTOGRAM {
+		signature := model.LabelsToSignature(p.currentLabels)
+		if histogram := p.histograms[signature]; histogram != nil {
+			p.currentMetric = histogram
+		} else {
+			p.histograms[signature] = p.currentMetric
+			p.currentMF.Metric = append(p.currentMF.Metric, p.currentMetric)
+		}
+	} else {
+		p.currentMF.Metric = append(p.currentMF.Metric, p.currentMetric)
+	}
+	if p.readTokenUntilWhitespace(); p.err != nil {
+		return nil // Unexpected end of input.
+	}
+	value, err := strconv.ParseFloat(p.currentToken.String(), 64)
+	if err != nil {
+		// Create a more helpful error message.
+		p.parseError(fmt.Sprintf("expected float as value, got %q", p.currentToken.String()))
+		return nil
+	}
+	switch p.currentMF.GetType() {
+	case dto.MetricType_COUNTER:
+		p.currentMetric.Counter = &dto.Counter{Value: proto.Float64(value)}
+	case dto.MetricType_GAUGE:
+		p.currentMetric.Gauge = &dto.Gauge{Value: proto.Float64(value)}
+	case dto.MetricType_UNTYPED:
+		p.currentMetric.Untyped = &dto.Untyped{Value: proto.Float64(value)}
+	case dto.MetricType_SUMMARY:
+		// *sigh*
+		if p.currentMetric.Summary == nil {
+			p.currentMetric.Summary = &dto.Summary{}
+		}
+		switch {
+		case p.currentIsSummaryCount:
+			p.currentMetric.Summary.SampleCount = proto.Uint64(uint64(value))
+		case p.currentIsSummarySum:
+			p.currentMetric.Summary.SampleSum = proto.Float64(value)
+		case !math.IsNaN(p.currentQuantile):
+			p.currentMetric.Summary.Quantile = append(
+				p.currentMetric.Summary.Quantile,
+				&dto.Quantile{
+					Quantile: proto.Float64(p.currentQuantile),
+					Value:    proto.Float64(value),
+				},
+			)
+		}
+	case dto.MetricType_HISTOGRAM:
+		// *sigh*
+		if p.currentMetric.Histogram == nil {
+			p.currentMetric.Histogram = &dto.Histogram{}
+		}
+		switch {
+		case p.currentIsHistogramCount:
+			p.currentMetric.Histogram.SampleCount = proto.Uint64(uint64(value))
+		case p.currentIsHistogramSum:
+			p.currentMetric.Histogram.SampleSum = proto.Float64(value)
+		case !math.IsNaN(p.currentBucket):
+			p.currentMetric.Histogram.Bucket = append(
+				p.currentMetric.Histogram.Bucket,
+				&dto.Bucket{
+					UpperBound:      proto.Float64(p.currentBucket),
+					CumulativeCount: proto.Uint64(uint64(value)),
+				},
+			)
+		}
+	default:
+		p.err = fmt.Errorf("unexpected type for metric name %q", p.currentMF.GetName())
+	}
+	if p.currentByte == '\n' {
+		return p.startOfLine
+	}
+	return p.startTimestamp
+}
+
+// startTimestamp represents the state where the next byte read from p.buf is
+// the start of the timestamp (or whitespace leading up to it).
+func (p *Parser) startTimestamp() stateFn {
+	if p.skipBlankTab(); p.err != nil {
+		return nil // Unexpected end of input.
+	}
+	if p.readTokenUntilWhitespace(); p.err != nil {
+		return nil // Unexpected end of input.
+	}
+	timestamp, err := strconv.ParseInt(p.currentToken.String(), 10, 64)
+	if err != nil {
+		// Create a more helpful error message.
+		p.parseError(fmt.Sprintf("expected integer as timestamp, got %q", p.currentToken.String()))
+		return nil
+	}
+	p.currentMetric.TimestampMs = proto.Int64(timestamp)
+	if p.readTokenUntilNewline(false); p.err != nil {
+		return nil // Unexpected end of input.
+	}
+	if p.currentToken.Len() > 0 {
+		p.parseError(fmt.Sprintf("spurious string after timestamp: %q", p.currentToken.String()))
+		return nil
+	}
+	return p.startOfLine
+}
+
+// readingHelp represents the state where the last byte read (now in
+// p.currentByte) is the first byte of the docstring after 'HELP'.
+func (p *Parser) readingHelp() stateFn {
+	if p.currentMF.Help != nil {
+		p.parseError(fmt.Sprintf("second HELP line for metric name %q", p.currentMF.GetName()))
+		return nil
+	}
+	// Rest of line is the docstring.
+	if p.readTokenUntilNewline(true); p.err != nil {
+		return nil // Unexpected end of input.
+	}
+	p.currentMF.Help = proto.String(p.currentToken.String())
+	return p.startOfLine
+}
+
+// readingType represents the state where the last byte read (now in
+// p.currentByte) is the first byte of the type hint after 'HELP'.
+func (p *Parser) readingType() stateFn {
+	if p.currentMF.Type != nil {
+		p.parseError(fmt.Sprintf("second TYPE line for metric name %q, or TYPE reported after samples", p.currentMF.GetName()))
+		return nil
+	}
+	// Rest of line is the type.
+	if p.readTokenUntilNewline(false); p.err != nil {
+		return nil // Unexpected end of input.
+	}
+	metricType, ok := dto.MetricType_value[strings.ToUpper(p.currentToken.String())]
+	if !ok {
+		p.parseError(fmt.Sprintf("unknown metric type %q", p.currentToken.String()))
+		return nil
+	}
+	p.currentMF.Type = dto.MetricType(metricType).Enum()
+	return p.startOfLine
+}
+
+// parseError sets p.err to a ParseError at the current line with the given
+// message.
+func (p *Parser) parseError(msg string) {
+	p.err = ParseError{
+		Line: p.lineCount,
+		Msg:  msg,
+	}
+}
+
+// skipBlankTab reads (and discards) bytes from p.buf until it encounters a byte
+// that is neither ' ' nor '\t'. That byte is left in p.currentByte.
+func (p *Parser) skipBlankTab() {
+	for {
+		if p.currentByte, p.err = p.buf.ReadByte(); p.err != nil || !isBlankOrTab(p.currentByte) {
+			return
+		}
+	}
+}
+
+// skipBlankTabIfCurrentBlankTab works exactly as skipBlankTab but doesn't do
+// anything if p.currentByte is neither ' ' nor '\t'.
+func (p *Parser) skipBlankTabIfCurrentBlankTab() {
+	if isBlankOrTab(p.currentByte) {
+		p.skipBlankTab()
+	}
+}
+
+// readTokenUntilWhitespace copies bytes from p.buf into p.currentToken.  The
+// first byte considered is the byte already read (now in p.currentByte).  The
+// first whitespace byte encountered is still copied into p.currentByte, but not
+// into p.currentToken.
+func (p *Parser) readTokenUntilWhitespace() {
+	p.currentToken.Reset()
+	for p.err == nil && !isBlankOrTab(p.currentByte) && p.currentByte != '\n' {
+		p.currentToken.WriteByte(p.currentByte)
+		p.currentByte, p.err = p.buf.ReadByte()
+	}
+}
+
+// readTokenUntilNewline copies bytes from p.buf into p.currentToken.  The first
+// byte considered is the byte already read (now in p.currentByte).  The first
+// newline byte encountered is still copied into p.currentByte, but not into
+// p.currentToken. If recognizeEscapeSequence is true, two escape sequences are
+// recognized: '\\' tranlates into '\', and '\n' into a line-feed character. All
+// other escape sequences are invalid and cause an error.
+func (p *Parser) readTokenUntilNewline(recognizeEscapeSequence bool) {
+	p.currentToken.Reset()
+	escaped := false
+	for p.err == nil {
+		if recognizeEscapeSequence && escaped {
+			switch p.currentByte {
+			case '\\':
+				p.currentToken.WriteByte(p.currentByte)
+			case 'n':
+				p.currentToken.WriteByte('\n')
+			default:
+				p.parseError(fmt.Sprintf("invalid escape sequence '\\%c'", p.currentByte))
+				return
+			}
+			escaped = false
+		} else {
+			switch p.currentByte {
+			case '\n':
+				return
+			case '\\':
+				escaped = true
+			default:
+				p.currentToken.WriteByte(p.currentByte)
+			}
+		}
+		p.currentByte, p.err = p.buf.ReadByte()
+	}
+}
+
+// readTokenAsMetricName copies a metric name from p.buf into p.currentToken.
+// The first byte considered is the byte already read (now in p.currentByte).
+// The first byte not part of a metric name is still copied into p.currentByte,
+// but not into p.currentToken.
+func (p *Parser) readTokenAsMetricName() {
+	p.currentToken.Reset()
+	if !isValidMetricNameStart(p.currentByte) {
+		return
+	}
+	for {
+		p.currentToken.WriteByte(p.currentByte)
+		p.currentByte, p.err = p.buf.ReadByte()
+		if p.err != nil || !isValidMetricNameContinuation(p.currentByte) {
+			return
+		}
+	}
+}
+
+// readTokenAsLabelName copies a label name from p.buf into p.currentToken.
+// The first byte considered is the byte already read (now in p.currentByte).
+// The first byte not part of a label name is still copied into p.currentByte,
+// but not into p.currentToken.
+func (p *Parser) readTokenAsLabelName() {
+	p.currentToken.Reset()
+	if !isValidLabelNameStart(p.currentByte) {
+		return
+	}
+	for {
+		p.currentToken.WriteByte(p.currentByte)
+		p.currentByte, p.err = p.buf.ReadByte()
+		if p.err != nil || !isValidLabelNameContinuation(p.currentByte) {
+			return
+		}
+	}
+}
+
+// readTokenAsLabelValue copies a label value from p.buf into p.currentToken.
+// In contrast to the other 'readTokenAs...' functions, which start with the
+// last read byte in p.currentByte, this method ignores p.currentByte and starts
+// with reading a new byte from p.buf. The first byte not part of a label value
+// is still copied into p.currentByte, but not into p.currentToken.
+func (p *Parser) readTokenAsLabelValue() {
+	p.currentToken.Reset()
+	escaped := false
+	for {
+		if p.currentByte, p.err = p.buf.ReadByte(); p.err != nil {
+			return
+		}
+		if escaped {
+			switch p.currentByte {
+			case '"', '\\':
+				p.currentToken.WriteByte(p.currentByte)
+			case 'n':
+				p.currentToken.WriteByte('\n')
+			default:
+				p.parseError(fmt.Sprintf("invalid escape sequence '\\%c'", p.currentByte))
+				return
+			}
+			escaped = false
+			continue
+		}
+		switch p.currentByte {
+		case '"':
+			return
+		case '\n':
+			p.parseError(fmt.Sprintf("label value %q contains unescaped new-line", p.currentToken.String()))
+			return
+		case '\\':
+			escaped = true
+		default:
+			p.currentToken.WriteByte(p.currentByte)
+		}
+	}
+}
+
+func (p *Parser) setOrCreateCurrentMF() {
+	p.currentIsSummaryCount = false
+	p.currentIsSummarySum = false
+	p.currentIsHistogramCount = false
+	p.currentIsHistogramSum = false
+	name := p.currentToken.String()
+	if p.currentMF = p.metricFamiliesByName[name]; p.currentMF != nil {
+		return
+	}
+	// Try out if this is a _sum or _count for a summary/histogram.
+	summaryName := summaryMetricName(name)
+	if p.currentMF = p.metricFamiliesByName[summaryName]; p.currentMF != nil {
+		if p.currentMF.GetType() == dto.MetricType_SUMMARY {
+			if isCount(name) {
+				p.currentIsSummaryCount = true
+			}
+			if isSum(name) {
+				p.currentIsSummarySum = true
+			}
+			return
+		}
+	}
+	histogramName := histogramMetricName(name)
+	if p.currentMF = p.metricFamiliesByName[histogramName]; p.currentMF != nil {
+		if p.currentMF.GetType() == dto.MetricType_HISTOGRAM {
+			if isCount(name) {
+				p.currentIsHistogramCount = true
+			}
+			if isSum(name) {
+				p.currentIsHistogramSum = true
+			}
+			return
+		}
+	}
+	p.currentMF = &dto.MetricFamily{Name: proto.String(name)}
+	p.metricFamiliesByName[name] = p.currentMF
+}
+
+func isValidLabelNameStart(b byte) bool {
+	return (b >= 'a' && b <= 'z') || (b >= 'A' && b <= 'Z') || b == '_'
+}
+
+func isValidLabelNameContinuation(b byte) bool {
+	return isValidLabelNameStart(b) || (b >= '0' && b <= '9')
+}
+
+func isValidMetricNameStart(b byte) bool {
+	return isValidLabelNameStart(b) || b == ':'
+}
+
+func isValidMetricNameContinuation(b byte) bool {
+	return isValidLabelNameContinuation(b) || b == ':'
+}
+
+func isBlankOrTab(b byte) bool {
+	return b == ' ' || b == '\t'
+}
+
+func isCount(name string) bool {
+	return len(name) > 6 && name[len(name)-6:] == "_count"
+}
+
+func isSum(name string) bool {
+	return len(name) > 4 && name[len(name)-4:] == "_sum"
+}
+
+func isBucket(name string) bool {
+	return len(name) > 7 && name[len(name)-7:] == "_bucket"
+}
+
+func summaryMetricName(name string) string {
+	switch {
+	case isCount(name):
+		return name[:len(name)-6]
+	case isSum(name):
+		return name[:len(name)-4]
+	default:
+		return name
+	}
+}
+
+func histogramMetricName(name string) string {
+	switch {
+	case isCount(name):
+		return name[:len(name)-6]
+	case isSum(name):
+		return name[:len(name)-4]
+	case isBucket(name):
+		return name[:len(name)-7]
+	default:
+		return name
+	}
+}

vendor/github.com/prometheus/client_golang/text/proto.go

@@ -0,0 +1,43 @@
+// Copyright 2014 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 text
+
+import (
+	"fmt"
+	"io"
+
+	"github.com/golang/protobuf/proto"
+	"github.com/matttproud/golang_protobuf_extensions/pbutil"
+
+	dto "github.com/prometheus/client_model/go"
+)
+
+// WriteProtoDelimited writes the MetricFamily to the writer in delimited
+// protobuf format and returns the number of bytes written and any error
+// encountered.
+func WriteProtoDelimited(w io.Writer, p *dto.MetricFamily) (int, error) {
+	return pbutil.WriteDelimited(w, p)
+}
+
+// WriteProtoText writes the MetricFamily to the writer in text format and
+// returns the number of bytes written and any error encountered.
+func WriteProtoText(w io.Writer, p *dto.MetricFamily) (int, error) {
+	return fmt.Fprintf(w, "%s\n", proto.MarshalTextString(p))
+}
+
+// WriteProtoCompactText writes the MetricFamily to the writer in compact text
+// format and returns the number of bytes written and any error encountered.
+func WriteProtoCompactText(w io.Writer, p *dto.MetricFamily) (int, error) {
+	return fmt.Fprintf(w, "%s\n", p)
+}

vendor/vendor.json

@@ -21,11 +21,21 @@
 			"revisionTime": "2016-04-24T11:30:07Z"
 		},
 		{
-			"checksumSHA1": "Ph+qmEo8RdBKBHZUhx0y5Oyk/U0=",
+			"checksumSHA1": "TpbZuXCQvnEiTzFc6jhTgFDop3M=",
+			"path": "github.com/prometheus/client_golang/model",
+			"revision": "6dbab8106ed3ed77359ac85d9cf08e30290df864"
+		},
+		{
+			"checksumSHA1": "lmxW0tuAU0yegSQqrzdepyqPLYQ=",
 			"path": "github.com/prometheus/client_golang/prometheus",
-			"revision": "5636dc67ae776adf5590da7349e70fbb9559972d",
+			"revision": "6dbab8106ed3ed77359ac85d9cf08e30290df864",
 			"revisionTime": "2016-09-16T18:03:40Z"
 		},
+		{
+			"checksumSHA1": "0fkxdi0g3zdiWGe/rQiJZKvO9Yc=",
+			"path": "github.com/prometheus/client_golang/text",
+			"revision": "6dbab8106ed3ed77359ac85d9cf08e30290df864"
+		},
 		{
 			"checksumSHA1": "DvwvOlPNAgRntBzt3b3OSRMS2N4=",
 			"path": "github.com/prometheus/client_model/go",