Re-vendor

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

@@ -0,0 +1,187 @@
+// Copyright 2018 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package testutil provides helpers to test code using the prometheus package
+// of client_golang.
+//
+// While writing unit tests to verify correct instrumentation of your code, it's
+// a common mistake to mostly test the instrumentation library instead of your
+// own code. Rather than verifying that a prometheus.Counter's value has changed
+// as expected or that it shows up in the exposition after registration, it is
+// in general more robust and more faithful to the concept of unit tests to use
+// mock implementations of the prometheus.Counter and prometheus.Registerer
+// interfaces that simply assert that the Add or Register methods have been
+// called with the expected arguments. However, this might be overkill in simple
+// scenarios. The ToFloat64 function is provided for simple inspection of a
+// single-value metric, but it has to be used with caution.
+//
+// End-to-end tests to verify all or larger parts of the metrics exposition can
+// be implemented with the CollectAndCompare or GatherAndCompare functions. The
+// most appropriate use is not so much testing instrumentation of your code, but
+// testing custom prometheus.Collector implementations and in particular whole
+// exporters, i.e. programs that retrieve telemetry data from a 3rd party source
+// and convert it into Prometheus metrics.
+package testutil
+
+import (
+	"bytes"
+	"fmt"
+	"io"
+
+	"github.com/prometheus/common/expfmt"
+
+	dto "github.com/prometheus/client_model/go"
+
+	"github.com/prometheus/client_golang/prometheus"
+	"github.com/prometheus/client_golang/prometheus/internal"
+)
+
+// ToFloat64 collects all Metrics from the provided Collector. It expects that
+// this results in exactly one Metric being collected, which must be a Gauge,
+// Counter, or Untyped. In all other cases, ToFloat64 panics. ToFloat64 returns
+// the value of the collected Metric.
+//
+// The Collector provided is typically a simple instance of Gauge or Counter, or
+// – less commonly – a GaugeVec or CounterVec with exactly one element. But any
+// Collector fulfilling the prerequisites described above will do.
+//
+// Use this function with caution. It is computationally very expensive and thus
+// not suited at all to read values from Metrics in regular code. This is really
+// only for testing purposes, and even for testing, other approaches are often
+// more appropriate (see this package's documentation).
+//
+// A clear anti-pattern would be to use a metric type from the prometheus
+// package to track values that are also needed for something else than the
+// exposition of Prometheus metrics. For example, you would like to track the
+// number of items in a queue because your code should reject queuing further
+// items if a certain limit is reached. It is tempting to track the number of
+// items in a prometheus.Gauge, as it is then easily available as a metric for
+// exposition, too. However, then you would need to call ToFloat64 in your
+// regular code, potentially quite often. The recommended way is to track the
+// number of items conventionally (in the way you would have done it without
+// considering Prometheus metrics) and then expose the number with a
+// prometheus.GaugeFunc.
+func ToFloat64(c prometheus.Collector) float64 {
+	var (
+		m      prometheus.Metric
+		mCount int
+		mChan  = make(chan prometheus.Metric)
+		done   = make(chan struct{})
+	)
+
+	go func() {
+		for m = range mChan {
+			mCount++
+		}
+		close(done)
+	}()
+
+	c.Collect(mChan)
+	close(mChan)
+	<-done
+
+	if mCount != 1 {
+		panic(fmt.Errorf("collected %d metrics instead of exactly 1", mCount))
+	}
+
+	pb := &dto.Metric{}
+	m.Write(pb)
+	if pb.Gauge != nil {
+		return pb.Gauge.GetValue()
+	}
+	if pb.Counter != nil {
+		return pb.Counter.GetValue()
+	}
+	if pb.Untyped != nil {
+		return pb.Untyped.GetValue()
+	}
+	panic(fmt.Errorf("collected a non-gauge/counter/untyped metric: %s", pb))
+}
+
+// CollectAndCompare registers the provided Collector with a newly created
+// pedantic Registry. It then does the same as GatherAndCompare, gathering the
+// metrics from the pedantic Registry.
+func CollectAndCompare(c prometheus.Collector, expected io.Reader, metricNames ...string) error {
+	reg := prometheus.NewPedanticRegistry()
+	if err := reg.Register(c); err != nil {
+		return fmt.Errorf("registering collector failed: %s", err)
+	}
+	return GatherAndCompare(reg, expected, metricNames...)
+}
+
+// GatherAndCompare gathers all metrics from the provided Gatherer and compares
+// it to an expected output read from the provided Reader in the Prometheus text
+// exposition format. If any metricNames are provided, only metrics with those
+// names are compared.
+func GatherAndCompare(g prometheus.Gatherer, expected io.Reader, metricNames ...string) error {
+	got, err := g.Gather()
+	if err != nil {
+		return fmt.Errorf("gathering metrics failed: %s", err)
+	}
+	if metricNames != nil {
+		got = filterMetrics(got, metricNames)
+	}
+	var tp expfmt.TextParser
+	wantRaw, err := tp.TextToMetricFamilies(expected)
+	if err != nil {
+		return fmt.Errorf("parsing expected metrics failed: %s", err)
+	}
+	want := internal.NormalizeMetricFamilies(wantRaw)
+
+	return compare(got, want)
+}
+
+// compare encodes both provided slices of metric families into the text format,
+// compares their string message, and returns an error if they do not match.
+// The error contains the encoded text of both the desired and the actual
+// result.
+func compare(got, want []*dto.MetricFamily) error {
+	var gotBuf, wantBuf bytes.Buffer
+	enc := expfmt.NewEncoder(&gotBuf, expfmt.FmtText)
+	for _, mf := range got {
+		if err := enc.Encode(mf); err != nil {
+			return fmt.Errorf("encoding gathered metrics failed: %s", err)
+		}
+	}
+	enc = expfmt.NewEncoder(&wantBuf, expfmt.FmtText)
+	for _, mf := range want {
+		if err := enc.Encode(mf); err != nil {
+			return fmt.Errorf("encoding expected metrics failed: %s", err)
+		}
+	}
+
+	if wantBuf.String() != gotBuf.String() {
+		return fmt.Errorf(`
+metric output does not match expectation; want:
+
+%s
+got:
+
+%s`, wantBuf.String(), gotBuf.String())
+
+	}
+	return nil
+}
+
+func filterMetrics(metrics []*dto.MetricFamily, names []string) []*dto.MetricFamily {
+	var filtered []*dto.MetricFamily
+	for _, m := range metrics {
+		for _, name := range names {
+			if m.GetName() == name {
+				filtered = append(filtered, m)
+				break
+			}
+		}
+	}
+	return filtered
+}

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

@@ -1,11 +1,14 @@
 // Code generated by protoc-gen-go. DO NOT EDIT.
 // source: metrics.proto
 
-package io_prometheus_client // import "github.com/prometheus/client_model/go"
+package io_prometheus_client
 
-import proto "github.com/golang/protobuf/proto"
-import fmt "fmt"
-import math "math"
+import (
+	fmt "fmt"
+	proto "github.com/golang/protobuf/proto"
+	timestamp "github.com/golang/protobuf/ptypes/timestamp"
+	math "math"
+)
 
 // Reference imports to suppress errors if they are not otherwise used.
 var _ = proto.Marshal
@@ -16,7 +19,7 @@ var _ = math.Inf
 // is compatible with the proto package it is being compiled against.
 // A compilation error at this line likely means your copy of the
 // proto package needs to be updated.
-const _ = proto.ProtoPackageIsVersion2 // please upgrade the proto package
+const _ = proto.ProtoPackageIsVersion3 // please upgrade the proto package
 
 type MetricType int32
 
@@ -35,6 +38,7 @@ var MetricType_name = map[int32]string{
 	3: "UNTYPED",
 	4: "HISTOGRAM",
 }
+
 var MetricType_value = map[string]int32{
 	"COUNTER":   0,
 	"GAUGE":     1,
@@ -48,9 +52,11 @@ func (x MetricType) Enum() *MetricType {
 	*p = x
 	return p
 }
+
 func (x MetricType) String() string {
 	return proto.EnumName(MetricType_name, int32(x))
 }
+
 func (x *MetricType) UnmarshalJSON(data []byte) error {
 	value, err := proto.UnmarshalJSONEnum(MetricType_value, data, "MetricType")
 	if err != nil {
@@ -59,8 +65,9 @@ func (x *MetricType) UnmarshalJSON(data []byte) error {
 	*x = MetricType(value)
 	return nil
 }
+
 func (MetricType) EnumDescriptor() ([]byte, []int) {
-	return fileDescriptor_metrics_c97c9a2b9560cb8f, []int{0}
+	return fileDescriptor_6039342a2ba47b72, []int{0}
 }
 
 type LabelPair struct {
@@ -75,16 +82,17 @@ func (m *LabelPair) Reset()         { *m = LabelPair{} }
 func (m *LabelPair) String() string { return proto.CompactTextString(m) }
 func (*LabelPair) ProtoMessage()    {}
 func (*LabelPair) Descriptor() ([]byte, []int) {
-	return fileDescriptor_metrics_c97c9a2b9560cb8f, []int{0}
+	return fileDescriptor_6039342a2ba47b72, []int{0}
 }
+
 func (m *LabelPair) XXX_Unmarshal(b []byte) error {
 	return xxx_messageInfo_LabelPair.Unmarshal(m, b)
 }
 func (m *LabelPair) XXX_Marshal(b []byte, deterministic bool) ([]byte, error) {
 	return xxx_messageInfo_LabelPair.Marshal(b, m, deterministic)
 }
-func (dst *LabelPair) XXX_Merge(src proto.Message) {
-	xxx_messageInfo_LabelPair.Merge(dst, src)
+func (m *LabelPair) XXX_Merge(src proto.Message) {
+	xxx_messageInfo_LabelPair.Merge(m, src)
 }
 func (m *LabelPair) XXX_Size() int {
 	return xxx_messageInfo_LabelPair.Size(m)
@@ -120,16 +128,17 @@ func (m *Gauge) Reset()         { *m = Gauge{} }
 func (m *Gauge) String() string { return proto.CompactTextString(m) }
 func (*Gauge) ProtoMessage()    {}
 func (*Gauge) Descriptor() ([]byte, []int) {
-	return fileDescriptor_metrics_c97c9a2b9560cb8f, []int{1}
+	return fileDescriptor_6039342a2ba47b72, []int{1}
 }
+
 func (m *Gauge) XXX_Unmarshal(b []byte) error {
 	return xxx_messageInfo_Gauge.Unmarshal(m, b)
 }
 func (m *Gauge) XXX_Marshal(b []byte, deterministic bool) ([]byte, error) {
 	return xxx_messageInfo_Gauge.Marshal(b, m, deterministic)
 }
-func (dst *Gauge) XXX_Merge(src proto.Message) {
-	xxx_messageInfo_Gauge.Merge(dst, src)
+func (m *Gauge) XXX_Merge(src proto.Message) {
+	xxx_messageInfo_Gauge.Merge(m, src)
 }
 func (m *Gauge) XXX_Size() int {
 	return xxx_messageInfo_Gauge.Size(m)
@@ -148,26 +157,28 @@ func (m *Gauge) GetValue() float64 {
 }
 
 type Counter struct {
-	Value                *float64 `protobuf:"fixed64,1,opt,name=value" json:"value,omitempty"`
-	XXX_NoUnkeyedLiteral struct{} `json:"-"`
-	XXX_unrecognized     []byte   `json:"-"`
-	XXX_sizecache        int32    `json:"-"`
+	Value                *float64  `protobuf:"fixed64,1,opt,name=value" json:"value,omitempty"`
+	Exemplar             *Exemplar `protobuf:"bytes,2,opt,name=exemplar" json:"exemplar,omitempty"`
+	XXX_NoUnkeyedLiteral struct{}  `json:"-"`
+	XXX_unrecognized     []byte    `json:"-"`
+	XXX_sizecache        int32     `json:"-"`
 }
 
 func (m *Counter) Reset()         { *m = Counter{} }
 func (m *Counter) String() string { return proto.CompactTextString(m) }
 func (*Counter) ProtoMessage()    {}
 func (*Counter) Descriptor() ([]byte, []int) {
-	return fileDescriptor_metrics_c97c9a2b9560cb8f, []int{2}
+	return fileDescriptor_6039342a2ba47b72, []int{2}
 }
+
 func (m *Counter) XXX_Unmarshal(b []byte) error {
 	return xxx_messageInfo_Counter.Unmarshal(m, b)
 }
 func (m *Counter) XXX_Marshal(b []byte, deterministic bool) ([]byte, error) {
 	return xxx_messageInfo_Counter.Marshal(b, m, deterministic)
 }
-func (dst *Counter) XXX_Merge(src proto.Message) {
-	xxx_messageInfo_Counter.Merge(dst, src)
+func (m *Counter) XXX_Merge(src proto.Message) {
+	xxx_messageInfo_Counter.Merge(m, src)
 }
 func (m *Counter) XXX_Size() int {
 	return xxx_messageInfo_Counter.Size(m)
@@ -185,6 +196,13 @@ func (m *Counter) GetValue() float64 {
 	return 0
 }
 
+func (m *Counter) GetExemplar() *Exemplar {
+	if m != nil {
+		return m.Exemplar
+	}
+	return nil
+}
+
 type Quantile struct {
 	Quantile             *float64 `protobuf:"fixed64,1,opt,name=quantile" json:"quantile,omitempty"`
 	Value                *float64 `protobuf:"fixed64,2,opt,name=value" json:"value,omitempty"`
@@ -197,16 +215,17 @@ func (m *Quantile) Reset()         { *m = Quantile{} }
 func (m *Quantile) String() string { return proto.CompactTextString(m) }
 func (*Quantile) ProtoMessage()    {}
 func (*Quantile) Descriptor() ([]byte, []int) {
-	return fileDescriptor_metrics_c97c9a2b9560cb8f, []int{3}
+	return fileDescriptor_6039342a2ba47b72, []int{3}
 }
+
 func (m *Quantile) XXX_Unmarshal(b []byte) error {
 	return xxx_messageInfo_Quantile.Unmarshal(m, b)
 }
 func (m *Quantile) XXX_Marshal(b []byte, deterministic bool) ([]byte, error) {
 	return xxx_messageInfo_Quantile.Marshal(b, m, deterministic)
 }
-func (dst *Quantile) XXX_Merge(src proto.Message) {
-	xxx_messageInfo_Quantile.Merge(dst, src)
+func (m *Quantile) XXX_Merge(src proto.Message) {
+	xxx_messageInfo_Quantile.Merge(m, src)
 }
 func (m *Quantile) XXX_Size() int {
 	return xxx_messageInfo_Quantile.Size(m)
@@ -244,16 +263,17 @@ func (m *Summary) Reset()         { *m = Summary{} }
 func (m *Summary) String() string { return proto.CompactTextString(m) }
 func (*Summary) ProtoMessage()    {}
 func (*Summary) Descriptor() ([]byte, []int) {
-	return fileDescriptor_metrics_c97c9a2b9560cb8f, []int{4}
+	return fileDescriptor_6039342a2ba47b72, []int{4}
 }
+
 func (m *Summary) XXX_Unmarshal(b []byte) error {
 	return xxx_messageInfo_Summary.Unmarshal(m, b)
 }
 func (m *Summary) XXX_Marshal(b []byte, deterministic bool) ([]byte, error) {
 	return xxx_messageInfo_Summary.Marshal(b, m, deterministic)
 }
-func (dst *Summary) XXX_Merge(src proto.Message) {
-	xxx_messageInfo_Summary.Merge(dst, src)
+func (m *Summary) XXX_Merge(src proto.Message) {
+	xxx_messageInfo_Summary.Merge(m, src)
 }
 func (m *Summary) XXX_Size() int {
 	return xxx_messageInfo_Summary.Size(m)
@@ -296,16 +316,17 @@ func (m *Untyped) Reset()         { *m = Untyped{} }
 func (m *Untyped) String() string { return proto.CompactTextString(m) }
 func (*Untyped) ProtoMessage()    {}
 func (*Untyped) Descriptor() ([]byte, []int) {
-	return fileDescriptor_metrics_c97c9a2b9560cb8f, []int{5}
+	return fileDescriptor_6039342a2ba47b72, []int{5}
 }
+
 func (m *Untyped) XXX_Unmarshal(b []byte) error {
 	return xxx_messageInfo_Untyped.Unmarshal(m, b)
 }
 func (m *Untyped) XXX_Marshal(b []byte, deterministic bool) ([]byte, error) {
 	return xxx_messageInfo_Untyped.Marshal(b, m, deterministic)
 }
-func (dst *Untyped) XXX_Merge(src proto.Message) {
-	xxx_messageInfo_Untyped.Merge(dst, src)
+func (m *Untyped) XXX_Merge(src proto.Message) {
+	xxx_messageInfo_Untyped.Merge(m, src)
 }
 func (m *Untyped) XXX_Size() int {
 	return xxx_messageInfo_Untyped.Size(m)
@@ -336,16 +357,17 @@ func (m *Histogram) Reset()         { *m = Histogram{} }
 func (m *Histogram) String() string { return proto.CompactTextString(m) }
 func (*Histogram) ProtoMessage()    {}
 func (*Histogram) Descriptor() ([]byte, []int) {
-	return fileDescriptor_metrics_c97c9a2b9560cb8f, []int{6}
+	return fileDescriptor_6039342a2ba47b72, []int{6}
 }
+
 func (m *Histogram) XXX_Unmarshal(b []byte) error {
 	return xxx_messageInfo_Histogram.Unmarshal(m, b)
 }
 func (m *Histogram) XXX_Marshal(b []byte, deterministic bool) ([]byte, error) {
 	return xxx_messageInfo_Histogram.Marshal(b, m, deterministic)
 }
-func (dst *Histogram) XXX_Merge(src proto.Message) {
-	xxx_messageInfo_Histogram.Merge(dst, src)
+func (m *Histogram) XXX_Merge(src proto.Message) {
+	xxx_messageInfo_Histogram.Merge(m, src)
 }
 func (m *Histogram) XXX_Size() int {
 	return xxx_messageInfo_Histogram.Size(m)
@@ -378,27 +400,29 @@ func (m *Histogram) GetBucket() []*Bucket {
 }
 
 type Bucket struct {
-	CumulativeCount      *uint64  `protobuf:"varint,1,opt,name=cumulative_count,json=cumulativeCount" json:"cumulative_count,omitempty"`
-	UpperBound           *float64 `protobuf:"fixed64,2,opt,name=upper_bound,json=upperBound" json:"upper_bound,omitempty"`
-	XXX_NoUnkeyedLiteral struct{} `json:"-"`
-	XXX_unrecognized     []byte   `json:"-"`
-	XXX_sizecache        int32    `json:"-"`
+	CumulativeCount      *uint64   `protobuf:"varint,1,opt,name=cumulative_count,json=cumulativeCount" json:"cumulative_count,omitempty"`
+	UpperBound           *float64  `protobuf:"fixed64,2,opt,name=upper_bound,json=upperBound" json:"upper_bound,omitempty"`
+	Exemplar             *Exemplar `protobuf:"bytes,3,opt,name=exemplar" json:"exemplar,omitempty"`
+	XXX_NoUnkeyedLiteral struct{}  `json:"-"`
+	XXX_unrecognized     []byte    `json:"-"`
+	XXX_sizecache        int32     `json:"-"`
 }
 
 func (m *Bucket) Reset()         { *m = Bucket{} }
 func (m *Bucket) String() string { return proto.CompactTextString(m) }
 func (*Bucket) ProtoMessage()    {}
 func (*Bucket) Descriptor() ([]byte, []int) {
-	return fileDescriptor_metrics_c97c9a2b9560cb8f, []int{7}
+	return fileDescriptor_6039342a2ba47b72, []int{7}
 }
+
 func (m *Bucket) XXX_Unmarshal(b []byte) error {
 	return xxx_messageInfo_Bucket.Unmarshal(m, b)
 }
 func (m *Bucket) XXX_Marshal(b []byte, deterministic bool) ([]byte, error) {
 	return xxx_messageInfo_Bucket.Marshal(b, m, deterministic)
 }
-func (dst *Bucket) XXX_Merge(src proto.Message) {
-	xxx_messageInfo_Bucket.Merge(dst, src)
+func (m *Bucket) XXX_Merge(src proto.Message) {
+	xxx_messageInfo_Bucket.Merge(m, src)
 }
 func (m *Bucket) XXX_Size() int {
 	return xxx_messageInfo_Bucket.Size(m)
@@ -423,6 +447,68 @@ func (m *Bucket) GetUpperBound() float64 {
 	return 0
 }
 
+func (m *Bucket) GetExemplar() *Exemplar {
+	if m != nil {
+		return m.Exemplar
+	}
+	return nil
+}
+
+type Exemplar struct {
+	Label                []*LabelPair         `protobuf:"bytes,1,rep,name=label" json:"label,omitempty"`
+	Value                *float64             `protobuf:"fixed64,2,opt,name=value" json:"value,omitempty"`
+	Timestamp            *timestamp.Timestamp `protobuf:"bytes,3,opt,name=timestamp" json:"timestamp,omitempty"`
+	XXX_NoUnkeyedLiteral struct{}             `json:"-"`
+	XXX_unrecognized     []byte               `json:"-"`
+	XXX_sizecache        int32                `json:"-"`
+}
+
+func (m *Exemplar) Reset()         { *m = Exemplar{} }
+func (m *Exemplar) String() string { return proto.CompactTextString(m) }
+func (*Exemplar) ProtoMessage()    {}
+func (*Exemplar) Descriptor() ([]byte, []int) {
+	return fileDescriptor_6039342a2ba47b72, []int{8}
+}
+
+func (m *Exemplar) XXX_Unmarshal(b []byte) error {
+	return xxx_messageInfo_Exemplar.Unmarshal(m, b)
+}
+func (m *Exemplar) XXX_Marshal(b []byte, deterministic bool) ([]byte, error) {
+	return xxx_messageInfo_Exemplar.Marshal(b, m, deterministic)
+}
+func (m *Exemplar) XXX_Merge(src proto.Message) {
+	xxx_messageInfo_Exemplar.Merge(m, src)
+}
+func (m *Exemplar) XXX_Size() int {
+	return xxx_messageInfo_Exemplar.Size(m)
+}
+func (m *Exemplar) XXX_DiscardUnknown() {
+	xxx_messageInfo_Exemplar.DiscardUnknown(m)
+}
+
+var xxx_messageInfo_Exemplar proto.InternalMessageInfo
+
+func (m *Exemplar) GetLabel() []*LabelPair {
+	if m != nil {
+		return m.Label
+	}
+	return nil
+}
+
+func (m *Exemplar) GetValue() float64 {
+	if m != nil && m.Value != nil {
+		return *m.Value
+	}
+	return 0
+}
+
+func (m *Exemplar) GetTimestamp() *timestamp.Timestamp {
+	if m != nil {
+		return m.Timestamp
+	}
+	return nil
+}
+
 type Metric struct {
 	Label                []*LabelPair `protobuf:"bytes,1,rep,name=label" json:"label,omitempty"`
 	Gauge                *Gauge       `protobuf:"bytes,2,opt,name=gauge" json:"gauge,omitempty"`
@@ -440,16 +526,17 @@ func (m *Metric) Reset()         { *m = Metric{} }
 func (m *Metric) String() string { return proto.CompactTextString(m) }
 func (*Metric) ProtoMessage()    {}
 func (*Metric) Descriptor() ([]byte, []int) {
-	return fileDescriptor_metrics_c97c9a2b9560cb8f, []int{8}
+	return fileDescriptor_6039342a2ba47b72, []int{9}
 }
+
 func (m *Metric) XXX_Unmarshal(b []byte) error {
 	return xxx_messageInfo_Metric.Unmarshal(m, b)
 }
 func (m *Metric) XXX_Marshal(b []byte, deterministic bool) ([]byte, error) {
 	return xxx_messageInfo_Metric.Marshal(b, m, deterministic)
 }
-func (dst *Metric) XXX_Merge(src proto.Message) {
-	xxx_messageInfo_Metric.Merge(dst, src)
+func (m *Metric) XXX_Merge(src proto.Message) {
+	xxx_messageInfo_Metric.Merge(m, src)
 }
 func (m *Metric) XXX_Size() int {
 	return xxx_messageInfo_Metric.Size(m)
@@ -523,16 +610,17 @@ func (m *MetricFamily) Reset()         { *m = MetricFamily{} }
 func (m *MetricFamily) String() string { return proto.CompactTextString(m) }
 func (*MetricFamily) ProtoMessage()    {}
 func (*MetricFamily) Descriptor() ([]byte, []int) {
-	return fileDescriptor_metrics_c97c9a2b9560cb8f, []int{9}
+	return fileDescriptor_6039342a2ba47b72, []int{10}
 }
+
 func (m *MetricFamily) XXX_Unmarshal(b []byte) error {
 	return xxx_messageInfo_MetricFamily.Unmarshal(m, b)
 }
 func (m *MetricFamily) XXX_Marshal(b []byte, deterministic bool) ([]byte, error) {
 	return xxx_messageInfo_MetricFamily.Marshal(b, m, deterministic)
 }
-func (dst *MetricFamily) XXX_Merge(src proto.Message) {
-	xxx_messageInfo_MetricFamily.Merge(dst, src)
+func (m *MetricFamily) XXX_Merge(src proto.Message) {
+	xxx_messageInfo_MetricFamily.Merge(m, src)
 }
 func (m *MetricFamily) XXX_Size() int {
 	return xxx_messageInfo_MetricFamily.Size(m)
@@ -572,6 +660,7 @@ func (m *MetricFamily) GetMetric() []*Metric {
 }
 
 func init() {
+	proto.RegisterEnum("io.prometheus.client.MetricType", MetricType_name, MetricType_value)
 	proto.RegisterType((*LabelPair)(nil), "io.prometheus.client.LabelPair")
 	proto.RegisterType((*Gauge)(nil), "io.prometheus.client.Gauge")
 	proto.RegisterType((*Counter)(nil), "io.prometheus.client.Counter")
@@ -580,50 +669,55 @@ func init() {
 	proto.RegisterType((*Untyped)(nil), "io.prometheus.client.Untyped")
 	proto.RegisterType((*Histogram)(nil), "io.prometheus.client.Histogram")
 	proto.RegisterType((*Bucket)(nil), "io.prometheus.client.Bucket")
+	proto.RegisterType((*Exemplar)(nil), "io.prometheus.client.Exemplar")
 	proto.RegisterType((*Metric)(nil), "io.prometheus.client.Metric")
 	proto.RegisterType((*MetricFamily)(nil), "io.prometheus.client.MetricFamily")
-	proto.RegisterEnum("io.prometheus.client.MetricType", MetricType_name, MetricType_value)
 }
 
-func init() { proto.RegisterFile("metrics.proto", fileDescriptor_metrics_c97c9a2b9560cb8f) }
+func init() { proto.RegisterFile("metrics.proto", fileDescriptor_6039342a2ba47b72) }
 
-var fileDescriptor_metrics_c97c9a2b9560cb8f = []byte{
-	// 591 bytes of a gzipped FileDescriptorProto
-	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xff, 0xac, 0x54, 0x4f, 0x4f, 0xdb, 0x4e,
-	0x14, 0xfc, 0x99, 0xd8, 0x09, 0x7e, 0x86, 0x5f, 0xad, 0x15, 0x07, 0xab, 0x2d, 0x25, 0xcd, 0x89,
-	0xf6, 0x10, 0x54, 0x04, 0xaa, 0x44, 0xdb, 0x03, 0x50, 0x1a, 0x2a, 0xd5, 0x40, 0x37, 0xc9, 0x81,
-	0x5e, 0xac, 0x8d, 0x59, 0x25, 0x56, 0xbd, 0xb6, 0x6b, 0xef, 0x22, 0xe5, 0xdc, 0x43, 0xbf, 0x47,
-	0xbf, 0x68, 0xab, 0xfd, 0xe3, 0x18, 0x24, 0xc3, 0xa9, 0xb7, 0xb7, 0xf3, 0x66, 0xde, 0x8e, 0x77,
-	0xc7, 0x0b, 0x9b, 0x8c, 0xf2, 0x32, 0x89, 0xab, 0x61, 0x51, 0xe6, 0x3c, 0x47, 0x5b, 0x49, 0x2e,
-	0x2b, 0x46, 0xf9, 0x82, 0x8a, 0x6a, 0x18, 0xa7, 0x09, 0xcd, 0xf8, 0xe0, 0x10, 0xdc, 0x2f, 0x64,
-	0x46, 0xd3, 0x2b, 0x92, 0x94, 0x08, 0x81, 0x9d, 0x11, 0x46, 0x03, 0xab, 0x6f, 0xed, 0xba, 0x58,
-	0xd5, 0x68, 0x0b, 0x9c, 0x5b, 0x92, 0x0a, 0x1a, 0xac, 0x29, 0x50, 0x2f, 0x06, 0xdb, 0xe0, 0x8c,
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-	0x01, 0xc2, 0x7b, 0x58, 0xff, 0x2a, 0x48, 0xc6, 0x93, 0x94, 0xa2, 0xa7, 0xb0, 0xfe, 0xc3, 0xd4,
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-	0xbd, 0x84, 0x8d, 0x8a, 0xb0, 0x22, 0xa5, 0x51, 0x2c, 0x77, 0x54, 0x13, 0x6c, 0xec, 0x69, 0x4c,
-	0x99, 0x40, 0xdb, 0x00, 0x86, 0x52, 0x09, 0x66, 0x26, 0xb9, 0x1a, 0x19, 0x0b, 0x86, 0x8e, 0xee,
-	0xec, 0xdf, 0xe9, 0x77, 0x76, 0xbd, 0xfd, 0x17, 0xc3, 0xb6, 0xb3, 0x1a, 0xd6, 0x8e, 0x1b, 0x7f,
-	0xf2, 0x43, 0xa7, 0x19, 0x5f, 0x16, 0xf4, 0xe6, 0x81, 0x0f, 0xfd, 0x69, 0x81, 0x7b, 0x9e, 0x54,
-	0x3c, 0x9f, 0x97, 0x84, 0xfd, 0x03, 0xb3, 0x07, 0xd0, 0x9d, 0x89, 0xf8, 0x3b, 0xe5, 0xc6, 0xea,
-	0xf3, 0x76, 0xab, 0x27, 0x8a, 0x83, 0x0d, 0x77, 0x30, 0x81, 0xae, 0x46, 0xd0, 0x2b, 0xf0, 0x63,
-	0xc1, 0x44, 0x4a, 0x78, 0x72, 0x7b, 0xdf, 0xc5, 0x93, 0x06, 0xd7, 0x4e, 0x76, 0xc0, 0x13, 0x45,
-	0x41, 0xcb, 0x68, 0x96, 0x8b, 0xec, 0xc6, 0x58, 0x01, 0x05, 0x9d, 0x48, 0x64, 0xf0, 0x67, 0x0d,
-	0xba, 0xa1, 0xca, 0x18, 0x3a, 0x04, 0x27, 0x95, 0x31, 0x0a, 0x2c, 0xe5, 0x6a, 0xa7, 0xdd, 0xd5,
-	0x2a, 0x69, 0x58, 0xb3, 0xd1, 0x1b, 0x70, 0xe6, 0x32, 0x46, 0x6a, 0xb8, 0xb7, 0xff, 0xac, 0x5d,
-	0xa6, 0x92, 0x86, 0x35, 0x13, 0xbd, 0x85, 0x5e, 0xac, 0xa3, 0x15, 0x74, 0x94, 0x68, 0xbb, 0x5d,
-	0x64, 0xf2, 0x87, 0x6b, 0xb6, 0x14, 0x56, 0x3a, 0x33, 0x81, 0xfd, 0x98, 0xd0, 0x04, 0x0b, 0xd7,
-	0x6c, 0x29, 0x14, 0xfa, 0x8e, 0x03, 0xe7, 0x31, 0xa1, 0x09, 0x02, 0xae, 0xd9, 0xe8, 0x03, 0xb8,
-	0x8b, 0xfa, 0xea, 0x83, 0x9e, 0x92, 0x3e, 0x70, 0x30, 0xab, 0x84, 0xe0, 0x46, 0x21, 0xc3, 0xc2,
-	0x13, 0x46, 0x2b, 0x4e, 0x58, 0x11, 0xb1, 0x2a, 0xe8, 0xf6, 0xad, 0xdd, 0x0e, 0xf6, 0x56, 0x58,
-	0x58, 0x0d, 0x7e, 0x5b, 0xb0, 0xa1, 0x6f, 0xe0, 0x13, 0x61, 0x49, 0xba, 0x6c, 0xfd, 0x83, 0x11,
-	0xd8, 0x0b, 0x9a, 0x16, 0xe6, 0x07, 0x56, 0x35, 0x3a, 0x00, 0x5b, 0x7a, 0x54, 0x47, 0xf8, 0xff,
-	0x7e, 0xbf, 0xdd, 0x95, 0x9e, 0x3c, 0x59, 0x16, 0x14, 0x2b, 0xb6, 0x0c, 0x9f, 0x7e, 0x53, 0x02,
-	0xfb, 0xb1, 0xf0, 0x69, 0x1d, 0x36, 0xdc, 0xd7, 0x21, 0x40, 0x33, 0x09, 0x79, 0xd0, 0x3b, 0xbd,
-	0x9c, 0x5e, 0x4c, 0xce, 0xb0, 0xff, 0x1f, 0x72, 0xc1, 0x19, 0x1d, 0x4f, 0x47, 0x67, 0xbe, 0x25,
-	0xf1, 0xf1, 0x34, 0x0c, 0x8f, 0xf1, 0xb5, 0xbf, 0x26, 0x17, 0xd3, 0x8b, 0xc9, 0xf5, 0xd5, 0xd9,
-	0x47, 0xbf, 0x83, 0x36, 0xc1, 0x3d, 0xff, 0x3c, 0x9e, 0x5c, 0x8e, 0xf0, 0x71, 0xe8, 0xdb, 0x27,
-	0x18, 0x5a, 0x5f, 0xb2, 0x6f, 0x47, 0xf3, 0x84, 0x2f, 0xc4, 0x6c, 0x18, 0xe7, 0x6c, 0xaf, 0xe9,
-	0xee, 0xe9, 0x6e, 0xc4, 0xf2, 0x1b, 0x9a, 0xee, 0xcd, 0xf3, 0x77, 0x49, 0x1e, 0x35, 0xdd, 0x48,
-	0x77, 0xff, 0x06, 0x00, 0x00, 0xff, 0xff, 0x45, 0x21, 0x7f, 0x64, 0x2b, 0x05, 0x00, 0x00,
+var fileDescriptor_6039342a2ba47b72 = []byte{
+	// 665 bytes of a gzipped FileDescriptorProto
+	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xff, 0xac, 0x54, 0xcd, 0x6e, 0xd3, 0x4c,
+	0x14, 0xfd, 0xdc, 0x38, 0x3f, 0xbe, 0x69, 0x3f, 0xa2, 0x51, 0x17, 0x56, 0xa1, 0x24, 0x78, 0x55,
+	0x58, 0x38, 0xa2, 0x6a, 0x05, 0x2a, 0xb0, 0x68, 0x4b, 0x48, 0x91, 0x48, 0x5b, 0x26, 0xc9, 0xa2,
+	0xb0, 0x88, 0x1c, 0x77, 0x70, 0x2c, 0x3c, 0xb1, 0xb1, 0x67, 0x2a, 0xb2, 0x66, 0xc1, 0x16, 0x5e,
+	0x81, 0x17, 0x05, 0xcd, 0x8f, 0x6d, 0x2a, 0xb9, 0x95, 0x40, 0xec, 0x66, 0xee, 0x3d, 0xe7, 0xfa,
+	0xcc, 0xf8, 0x9c, 0x81, 0x0d, 0x4a, 0x58, 0x1a, 0xfa, 0x99, 0x9b, 0xa4, 0x31, 0x8b, 0xd1, 0x66,
+	0x18, 0x8b, 0x15, 0x25, 0x6c, 0x41, 0x78, 0xe6, 0xfa, 0x51, 0x48, 0x96, 0x6c, 0xab, 0x1b, 0xc4,
+	0x71, 0x10, 0x91, 0xbe, 0xc4, 0xcc, 0xf9, 0x87, 0x3e, 0x0b, 0x29, 0xc9, 0x98, 0x47, 0x13, 0x45,
+	0x73, 0xf6, 0xc1, 0x7a, 0xe3, 0xcd, 0x49, 0x74, 0xee, 0x85, 0x29, 0x42, 0x60, 0x2e, 0x3d, 0x4a,
+	0x6c, 0xa3, 0x67, 0xec, 0x58, 0x58, 0xae, 0xd1, 0x26, 0xd4, 0xaf, 0xbc, 0x88, 0x13, 0x7b, 0x4d,
+	0x16, 0xd5, 0xc6, 0xd9, 0x86, 0xfa, 0xd0, 0xe3, 0xc1, 0x6f, 0x6d, 0xc1, 0x31, 0xf2, 0xf6, 0x7b,
+	0x68, 0x1e, 0xc7, 0x7c, 0xc9, 0x48, 0x5a, 0x0d, 0x40, 0x07, 0xd0, 0x22, 0x9f, 0x09, 0x4d, 0x22,
+	0x2f, 0x95, 0x83, 0xdb, 0xbb, 0xf7, 0xdd, 0xaa, 0x03, 0xb8, 0x03, 0x8d, 0xc2, 0x05, 0xde, 0x79,
+	0x0e, 0xad, 0xb7, 0xdc, 0x5b, 0xb2, 0x30, 0x22, 0x68, 0x0b, 0x5a, 0x9f, 0xf4, 0x5a, 0x7f, 0xa0,
+	0xd8, 0x5f, 0x57, 0x5e, 0x48, 0xfb, 0x6a, 0x40, 0x73, 0xcc, 0x29, 0xf5, 0xd2, 0x15, 0x7a, 0x00,
+	0xeb, 0x99, 0x47, 0x93, 0x88, 0xcc, 0x7c, 0xa1, 0x56, 0x4e, 0x30, 0x71, 0x5b, 0xd5, 0xe4, 0x01,
+	0xd0, 0x36, 0x80, 0x86, 0x64, 0x9c, 0xea, 0x49, 0x96, 0xaa, 0x8c, 0x39, 0x15, 0xe7, 0x28, 0xbe,
+	0x5f, 0xeb, 0xd5, 0x6e, 0x3e, 0x47, 0xae, 0xb8, 0xd4, 0xe7, 0x74, 0xa1, 0x39, 0x5d, 0xb2, 0x55,
+	0x42, 0x2e, 0x6f, 0xb8, 0xc5, 0x2f, 0x06, 0x58, 0x27, 0x61, 0xc6, 0xe2, 0x20, 0xf5, 0xe8, 0x3f,
+	0x10, 0xbb, 0x07, 0x8d, 0x39, 0xf7, 0x3f, 0x12, 0xa6, 0xa5, 0xde, 0xab, 0x96, 0x7a, 0x24, 0x31,
+	0x58, 0x63, 0x9d, 0x6f, 0x06, 0x34, 0x54, 0x09, 0x3d, 0x84, 0x8e, 0xcf, 0x29, 0x8f, 0x3c, 0x16,
+	0x5e, 0x5d, 0x97, 0x71, 0xa7, 0xac, 0x2b, 0x29, 0x5d, 0x68, 0xf3, 0x24, 0x21, 0xe9, 0x6c, 0x1e,
+	0xf3, 0xe5, 0xa5, 0xd6, 0x02, 0xb2, 0x74, 0x24, 0x2a, 0xd7, 0x1c, 0x50, 0xfb, 0x43, 0x07, 0x7c,
+	0x37, 0xa0, 0x95, 0x97, 0xd1, 0x3e, 0xd4, 0x23, 0xe1, 0x60, 0xdb, 0x90, 0x87, 0xea, 0x56, 0x4f,
+	0x29, 0x4c, 0x8e, 0x15, 0xba, 0xda, 0x1d, 0xe8, 0x29, 0x58, 0x45, 0x42, 0xb4, 0xac, 0x2d, 0x57,
+	0x65, 0xc8, 0xcd, 0x33, 0xe4, 0x4e, 0x72, 0x04, 0x2e, 0xc1, 0xce, 0xcf, 0x35, 0x68, 0x8c, 0x64,
+	0x22, 0xff, 0x56, 0xd1, 0x63, 0xa8, 0x07, 0x22, 0x53, 0x3a, 0x10, 0x77, 0xab, 0x69, 0x32, 0x76,
+	0x58, 0x21, 0xd1, 0x13, 0x68, 0xfa, 0x2a, 0x67, 0x5a, 0xec, 0x76, 0x35, 0x49, 0x87, 0x11, 0xe7,
+	0x68, 0x41, 0xcc, 0x54, 0x08, 0x6c, 0xf3, 0x36, 0xa2, 0x4e, 0x0a, 0xce, 0xd1, 0x82, 0xc8, 0x95,
+	0x69, 0xed, 0xfa, 0x6d, 0x44, 0xed, 0x6c, 0x9c, 0xa3, 0xd1, 0x0b, 0xb0, 0x16, 0xb9, 0x97, 0xed,
+	0xa6, 0xa4, 0xde, 0x70, 0x31, 0x85, 0xe5, 0x71, 0xc9, 0x10, 0xee, 0x2f, 0xee, 0x7a, 0x46, 0x33,
+	0xbb, 0xd1, 0x33, 0x76, 0x6a, 0xb8, 0x5d, 0xd4, 0x46, 0x99, 0xf3, 0xc3, 0x80, 0x75, 0xf5, 0x07,
+	0x5e, 0x79, 0x34, 0x8c, 0x56, 0x95, 0xcf, 0x19, 0x02, 0x73, 0x41, 0xa2, 0x44, 0xbf, 0x66, 0x72,
+	0x8d, 0xf6, 0xc0, 0x14, 0x1a, 0xe5, 0x15, 0xfe, 0xbf, 0xdb, 0xab, 0x56, 0xa5, 0x26, 0x4f, 0x56,
+	0x09, 0xc1, 0x12, 0x2d, 0xd2, 0xa4, 0x5e, 0x60, 0xdb, 0xbc, 0x2d, 0x4d, 0x8a, 0x87, 0x35, 0xf6,
+	0xd1, 0x08, 0xa0, 0x9c, 0x84, 0xda, 0xd0, 0x3c, 0x3e, 0x9b, 0x9e, 0x4e, 0x06, 0xb8, 0xf3, 0x1f,
+	0xb2, 0xa0, 0x3e, 0x3c, 0x9c, 0x0e, 0x07, 0x1d, 0x43, 0xd4, 0xc7, 0xd3, 0xd1, 0xe8, 0x10, 0x5f,
+	0x74, 0xd6, 0xc4, 0x66, 0x7a, 0x3a, 0xb9, 0x38, 0x1f, 0xbc, 0xec, 0xd4, 0xd0, 0x06, 0x58, 0x27,
+	0xaf, 0xc7, 0x93, 0xb3, 0x21, 0x3e, 0x1c, 0x75, 0xcc, 0x23, 0x0c, 0x95, 0xef, 0xfe, 0xbb, 0x83,
+	0x20, 0x64, 0x0b, 0x3e, 0x77, 0xfd, 0x98, 0xf6, 0xcb, 0x6e, 0x5f, 0x75, 0x67, 0x34, 0xbe, 0x24,
+	0x51, 0x3f, 0x88, 0x9f, 0x85, 0xf1, 0xac, 0xec, 0xce, 0x54, 0xf7, 0x57, 0x00, 0x00, 0x00, 0xff,
+	0xff, 0xd0, 0x84, 0x91, 0x73, 0x59, 0x06, 0x00, 0x00,
 }

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

@@ -30,17 +30,38 @@ type Encoder interface {
 	Encode(*dto.MetricFamily) error
 }
 
-type encoder func(*dto.MetricFamily) error
-
-func (e encoder) Encode(v *dto.MetricFamily) error {
-	return e(v)
+// Closer is implemented by Encoders that need to be closed to finalize
+// encoding. (For example, OpenMetrics needs a final `# EOF` line.)
+//
+// Note that all Encoder implementations returned from this package implement
+// Closer, too, even if the Close call is a no-op. This happens in preparation
+// for adding a Close method to the Encoder interface directly in a (mildly
+// breaking) release in the future.
+type Closer interface {
+	Close() error
 }
 
-// Negotiate returns the Content-Type based on the given Accept header.
-// If no appropriate accepted type is found, FmtText is returned.
+type encoderCloser struct {
+	encode func(*dto.MetricFamily) error
+	close  func() error
+}
+
+func (ec encoderCloser) Encode(v *dto.MetricFamily) error {
+	return ec.encode(v)
+}
+
+func (ec encoderCloser) Close() error {
+	return ec.close()
+}
+
+// Negotiate returns the Content-Type based on the given Accept header. If no
+// appropriate accepted type is found, FmtText is returned (which is the
+// Prometheus text format). This function will never negotiate FmtOpenMetrics,
+// as the support is still experimental. To include the option to negotiate
+// FmtOpenMetrics, use NegotiateOpenMetrics.
 func Negotiate(h http.Header) Format {
 	for _, ac := range goautoneg.ParseAccept(h.Get(hdrAccept)) {
-		// Check for protocol buffer
+		ver := ac.Params["version"]
 		if ac.Type+"/"+ac.SubType == ProtoType && ac.Params["proto"] == ProtoProtocol {
 			switch ac.Params["encoding"] {
 			case "delimited":
@@ -51,8 +72,6 @@ func Negotiate(h http.Header) Format {
 				return FmtProtoCompact
 			}
 		}
-		// Check for text format.
-		ver := ac.Params["version"]
 		if ac.Type == "text" && ac.SubType == "plain" && (ver == TextVersion || ver == "") {
 			return FmtText
 		}
@@ -60,29 +79,84 @@ func Negotiate(h http.Header) Format {
 	return FmtText
 }
 
-// NewEncoder returns a new encoder based on content type negotiation.
+// NegotiateIncludingOpenMetrics works like Negotiate but includes
+// FmtOpenMetrics as an option for the result. Note that this function is
+// temporary and will disappear once FmtOpenMetrics is fully supported and as
+// such may be negotiated by the normal Negotiate function.
+func NegotiateIncludingOpenMetrics(h http.Header) Format {
+	for _, ac := range goautoneg.ParseAccept(h.Get(hdrAccept)) {
+		ver := ac.Params["version"]
+		if ac.Type+"/"+ac.SubType == ProtoType && ac.Params["proto"] == ProtoProtocol {
+			switch ac.Params["encoding"] {
+			case "delimited":
+				return FmtProtoDelim
+			case "text":
+				return FmtProtoText
+			case "compact-text":
+				return FmtProtoCompact
+			}
+		}
+		if ac.Type == "text" && ac.SubType == "plain" && (ver == TextVersion || ver == "") {
+			return FmtText
+		}
+		if ac.Type+"/"+ac.SubType == OpenMetricsType && (ver == OpenMetricsVersion || ver == "") {
+			return FmtOpenMetrics
+		}
+	}
+	return FmtText
+}
+
+// NewEncoder returns a new encoder based on content type negotiation. All
+// Encoder implementations returned by NewEncoder also implement Closer, and
+// callers should always call the Close method. It is currently only required
+// for FmtOpenMetrics, but a future (breaking) release will add the Close method
+// to the Encoder interface directly. The current version of the Encoder
+// interface is kept for backwards compatibility.
 func NewEncoder(w io.Writer, format Format) Encoder {
 	switch format {
 	case FmtProtoDelim:
-		return encoder(func(v *dto.MetricFamily) error {
-			_, err := pbutil.WriteDelimited(w, v)
-			return err
-		})
+		return encoderCloser{
+			encode: func(v *dto.MetricFamily) error {
+				_, err := pbutil.WriteDelimited(w, v)
+				return err
+			},
+			close: func() error { return nil },
+		}
 	case FmtProtoCompact:
-		return encoder(func(v *dto.MetricFamily) error {
-			_, err := fmt.Fprintln(w, v.String())
-			return err
-		})
+		return encoderCloser{
+			encode: func(v *dto.MetricFamily) error {
+				_, err := fmt.Fprintln(w, v.String())
+				return err
+			},
+			close: func() error { return nil },
+		}
 	case FmtProtoText:
-		return encoder(func(v *dto.MetricFamily) error {
-			_, err := fmt.Fprintln(w, proto.MarshalTextString(v))
-			return err
-		})
+		return encoderCloser{
+			encode: func(v *dto.MetricFamily) error {
+				_, err := fmt.Fprintln(w, proto.MarshalTextString(v))
+				return err
+			},
+			close: func() error { return nil },
+		}
 	case FmtText:
-		return encoder(func(v *dto.MetricFamily) error {
-			_, err := MetricFamilyToText(w, v)
-			return err
-		})
+		return encoderCloser{
+			encode: func(v *dto.MetricFamily) error {
+				_, err := MetricFamilyToText(w, v)
+				return err
+			},
+			close: func() error { return nil },
+		}
+	case FmtOpenMetrics:
+		return encoderCloser{
+			encode: func(v *dto.MetricFamily) error {
+				_, err := MetricFamilyToOpenMetrics(w, v)
+				return err
+			},
+			close: func() error {
+				_, err := FinalizeOpenMetrics(w)
+				return err
+			},
+		}
 	}
-	panic("expfmt.NewEncoder: unknown format")
+	panic(fmt.Errorf("expfmt.NewEncoder: unknown format %q", format))
 }

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

@@ -19,10 +19,12 @@ type Format string
 
 // Constants to assemble the Content-Type values for the different wire protocols.
 const (
-	TextVersion   = "0.0.4"
-	ProtoType     = `application/vnd.google.protobuf`
-	ProtoProtocol = `io.prometheus.client.MetricFamily`
-	ProtoFmt      = ProtoType + "; proto=" + ProtoProtocol + ";"
+	TextVersion        = "0.0.4"
+	ProtoType          = `application/vnd.google.protobuf`
+	ProtoProtocol      = `io.prometheus.client.MetricFamily`
+	ProtoFmt           = ProtoType + "; proto=" + ProtoProtocol + ";"
+	OpenMetricsType    = `application/openmetrics-text`
+	OpenMetricsVersion = "0.0.1"
 
 	// The Content-Type values for the different wire protocols.
 	FmtUnknown      Format = `<unknown>`
@@ -30,6 +32,7 @@ const (
 	FmtProtoDelim   Format = ProtoFmt + ` encoding=delimited`
 	FmtProtoText    Format = ProtoFmt + ` encoding=text`
 	FmtProtoCompact Format = ProtoFmt + ` encoding=compact-text`
+	FmtOpenMetrics  Format = OpenMetricsType + `; version=` + OpenMetricsVersion + `; charset=utf-8`
 )
 
 const (

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

@@ -0,0 +1,527 @@
+// Copyright 2020 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 expfmt
+
+import (
+	"bufio"
+	"bytes"
+	"fmt"
+	"io"
+	"math"
+	"strconv"
+	"strings"
+
+	"github.com/golang/protobuf/ptypes"
+	"github.com/prometheus/common/model"
+
+	dto "github.com/prometheus/client_model/go"
+)
+
+// MetricFamilyToOpenMetrics converts a MetricFamily proto message into the
+// OpenMetrics text format and writes the resulting lines to 'out'. It returns
+// the number of bytes written and any error encountered. The output will have
+// the same order as the input, no further sorting is performed. Furthermore,
+// this function assumes the input is already sanitized and does not perform any
+// sanity checks. If the input contains duplicate metrics or invalid metric or
+// label names, the conversion will result in invalid text format output.
+//
+// This function fulfills the type 'expfmt.encoder'.
+//
+// Note that OpenMetrics requires a final `# EOF` line. Since this function acts
+// on individual metric families, it is the responsibility of the caller to
+// append this line to 'out' once all metric families have been written.
+// Conveniently, this can be done by calling FinalizeOpenMetrics.
+//
+// The output should be fully OpenMetrics compliant. However, there are a few
+// missing features and peculiarities to avoid complications when switching from
+// Prometheus to OpenMetrics or vice versa:
+//
+// - Counters are expected to have the `_total` suffix in their metric name. In
+//   the output, the suffix will be truncated from the `# TYPE` and `# HELP`
+//   line. A counter with a missing `_total` suffix is not an error. However,
+//   its type will be set to `unknown` in that case to avoid invalid OpenMetrics
+//   output.
+//
+// - No support for the following (optional) features: `# UNIT` line, `_created`
+//   line, info type, stateset type, gaugehistogram type.
+//
+// - The size of exemplar labels is not checked (i.e. it's possible to create
+//   exemplars that are larger than allowed by the OpenMetrics specification).
+//
+// - The value of Counters is not checked. (OpenMetrics doesn't allow counters
+//   with a `NaN` value.)
+func MetricFamilyToOpenMetrics(out io.Writer, in *dto.MetricFamily) (written int, err error) {
+	name := in.GetName()
+	if name == "" {
+		return 0, fmt.Errorf("MetricFamily has no name: %s", in)
+	}
+
+	// Try the interface upgrade. If it doesn't work, we'll use a
+	// bufio.Writer from the sync.Pool.
+	w, ok := out.(enhancedWriter)
+	if !ok {
+		b := bufPool.Get().(*bufio.Writer)
+		b.Reset(out)
+		w = b
+		defer func() {
+			bErr := b.Flush()
+			if err == nil {
+				err = bErr
+			}
+			bufPool.Put(b)
+		}()
+	}
+
+	var (
+		n          int
+		metricType = in.GetType()
+		shortName  = name
+	)
+	if metricType == dto.MetricType_COUNTER && strings.HasSuffix(shortName, "_total") {
+		shortName = name[:len(name)-6]
+	}
+
+	// Comments, first HELP, then TYPE.
+	if in.Help != nil {
+		n, err = w.WriteString("# HELP ")
+		written += n
+		if err != nil {
+			return
+		}
+		n, err = w.WriteString(shortName)
+		written += n
+		if err != nil {
+			return
+		}
+		err = w.WriteByte(' ')
+		written++
+		if err != nil {
+			return
+		}
+		n, err = writeEscapedString(w, *in.Help, true)
+		written += n
+		if err != nil {
+			return
+		}
+		err = w.WriteByte('\n')
+		written++
+		if err != nil {
+			return
+		}
+	}
+	n, err = w.WriteString("# TYPE ")
+	written += n
+	if err != nil {
+		return
+	}
+	n, err = w.WriteString(shortName)
+	written += n
+	if err != nil {
+		return
+	}
+	switch metricType {
+	case dto.MetricType_COUNTER:
+		if strings.HasSuffix(name, "_total") {
+			n, err = w.WriteString(" counter\n")
+		} else {
+			n, err = w.WriteString(" unknown\n")
+		}
+	case dto.MetricType_GAUGE:
+		n, err = w.WriteString(" gauge\n")
+	case dto.MetricType_SUMMARY:
+		n, err = w.WriteString(" summary\n")
+	case dto.MetricType_UNTYPED:
+		n, err = w.WriteString(" unknown\n")
+	case dto.MetricType_HISTOGRAM:
+		n, err = w.WriteString(" histogram\n")
+	default:
+		return written, fmt.Errorf("unknown metric type %s", metricType.String())
+	}
+	written += n
+	if err != nil {
+		return
+	}
+
+	// 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,
+				)
+			}
+			// Note that we have ensured above that either the name
+			// ends on `_total` or that the rendered type is
+			// `unknown`. Therefore, no `_total` must be added here.
+			n, err = writeOpenMetricsSample(
+				w, name, "", metric, "", 0,
+				metric.Counter.GetValue(), 0, false,
+				metric.Counter.Exemplar,
+			)
+		case dto.MetricType_GAUGE:
+			if metric.Gauge == nil {
+				return written, fmt.Errorf(
+					"expected gauge in metric %s %s", name, metric,
+				)
+			}
+			n, err = writeOpenMetricsSample(
+				w, name, "", metric, "", 0,
+				metric.Gauge.GetValue(), 0, false,
+				nil,
+			)
+		case dto.MetricType_UNTYPED:
+			if metric.Untyped == nil {
+				return written, fmt.Errorf(
+					"expected untyped in metric %s %s", name, metric,
+				)
+			}
+			n, err = writeOpenMetricsSample(
+				w, name, "", metric, "", 0,
+				metric.Untyped.GetValue(), 0, false,
+				nil,
+			)
+		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 = writeOpenMetricsSample(
+					w, name, "", metric,
+					model.QuantileLabel, q.GetQuantile(),
+					q.GetValue(), 0, false,
+					nil,
+				)
+				written += n
+				if err != nil {
+					return
+				}
+			}
+			n, err = writeOpenMetricsSample(
+				w, name, "_sum", metric, "", 0,
+				metric.Summary.GetSampleSum(), 0, false,
+				nil,
+			)
+			written += n
+			if err != nil {
+				return
+			}
+			n, err = writeOpenMetricsSample(
+				w, name, "_count", metric, "", 0,
+				0, metric.Summary.GetSampleCount(), true,
+				nil,
+			)
+		case dto.MetricType_HISTOGRAM:
+			if metric.Histogram == nil {
+				return written, fmt.Errorf(
+					"expected histogram in metric %s %s", name, metric,
+				)
+			}
+			infSeen := false
+			for _, b := range metric.Histogram.Bucket {
+				n, err = writeOpenMetricsSample(
+					w, name, "_bucket", metric,
+					model.BucketLabel, b.GetUpperBound(),
+					0, b.GetCumulativeCount(), true,
+					b.Exemplar,
+				)
+				written += n
+				if err != nil {
+					return
+				}
+				if math.IsInf(b.GetUpperBound(), +1) {
+					infSeen = true
+				}
+			}
+			if !infSeen {
+				n, err = writeOpenMetricsSample(
+					w, name, "_bucket", metric,
+					model.BucketLabel, math.Inf(+1),
+					0, metric.Histogram.GetSampleCount(), true,
+					nil,
+				)
+				written += n
+				if err != nil {
+					return
+				}
+			}
+			n, err = writeOpenMetricsSample(
+				w, name, "_sum", metric, "", 0,
+				metric.Histogram.GetSampleSum(), 0, false,
+				nil,
+			)
+			written += n
+			if err != nil {
+				return
+			}
+			n, err = writeOpenMetricsSample(
+				w, name, "_count", metric, "", 0,
+				0, metric.Histogram.GetSampleCount(), true,
+				nil,
+			)
+		default:
+			return written, fmt.Errorf(
+				"unexpected type in metric %s %s", name, metric,
+			)
+		}
+		written += n
+		if err != nil {
+			return
+		}
+	}
+	return
+}
+
+// FinalizeOpenMetrics writes the final `# EOF\n` line required by OpenMetrics.
+func FinalizeOpenMetrics(w io.Writer) (written int, err error) {
+	return w.Write([]byte("# EOF\n"))
+}
+
+// writeOpenMetricsSample writes a single sample in OpenMetrics text format to
+// w, given the metric name, the metric proto message itself, optionally an
+// additional label name with a float64 value (use empty string as label name if
+// not required), the value (optionally as float64 or uint64, determined by
+// useIntValue), and optionally an exemplar (use nil if not required). The
+// function returns the number of bytes written and any error encountered.
+func writeOpenMetricsSample(
+	w enhancedWriter,
+	name, suffix string,
+	metric *dto.Metric,
+	additionalLabelName string, additionalLabelValue float64,
+	floatValue float64, intValue uint64, useIntValue bool,
+	exemplar *dto.Exemplar,
+) (int, error) {
+	var written int
+	n, err := w.WriteString(name)
+	written += n
+	if err != nil {
+		return written, err
+	}
+	if suffix != "" {
+		n, err = w.WriteString(suffix)
+		written += n
+		if err != nil {
+			return written, err
+		}
+	}
+	n, err = writeOpenMetricsLabelPairs(
+		w, metric.Label, additionalLabelName, additionalLabelValue,
+	)
+	written += n
+	if err != nil {
+		return written, err
+	}
+	err = w.WriteByte(' ')
+	written++
+	if err != nil {
+		return written, err
+	}
+	if useIntValue {
+		n, err = writeUint(w, intValue)
+	} else {
+		n, err = writeOpenMetricsFloat(w, floatValue)
+	}
+	written += n
+	if err != nil {
+		return written, err
+	}
+	if metric.TimestampMs != nil {
+		err = w.WriteByte(' ')
+		written++
+		if err != nil {
+			return written, err
+		}
+		// TODO(beorn7): Format this directly without converting to a float first.
+		n, err = writeOpenMetricsFloat(w, float64(*metric.TimestampMs)/1000)
+		written += n
+		if err != nil {
+			return written, err
+		}
+	}
+	if exemplar != nil {
+		n, err = writeExemplar(w, exemplar)
+		written += n
+		if err != nil {
+			return written, err
+		}
+	}
+	err = w.WriteByte('\n')
+	written++
+	if err != nil {
+		return written, err
+	}
+	return written, nil
+}
+
+// writeOpenMetricsLabelPairs works like writeOpenMetrics but formats the float
+// in OpenMetrics style.
+func writeOpenMetricsLabelPairs(
+	w enhancedWriter,
+	in []*dto.LabelPair,
+	additionalLabelName string, additionalLabelValue float64,
+) (int, error) {
+	if len(in) == 0 && additionalLabelName == "" {
+		return 0, nil
+	}
+	var (
+		written   int
+		separator byte = '{'
+	)
+	for _, lp := range in {
+		err := w.WriteByte(separator)
+		written++
+		if err != nil {
+			return written, err
+		}
+		n, err := w.WriteString(lp.GetName())
+		written += n
+		if err != nil {
+			return written, err
+		}
+		n, err = w.WriteString(`="`)
+		written += n
+		if err != nil {
+			return written, err
+		}
+		n, err = writeEscapedString(w, lp.GetValue(), true)
+		written += n
+		if err != nil {
+			return written, err
+		}
+		err = w.WriteByte('"')
+		written++
+		if err != nil {
+			return written, err
+		}
+		separator = ','
+	}
+	if additionalLabelName != "" {
+		err := w.WriteByte(separator)
+		written++
+		if err != nil {
+			return written, err
+		}
+		n, err := w.WriteString(additionalLabelName)
+		written += n
+		if err != nil {
+			return written, err
+		}
+		n, err = w.WriteString(`="`)
+		written += n
+		if err != nil {
+			return written, err
+		}
+		n, err = writeOpenMetricsFloat(w, additionalLabelValue)
+		written += n
+		if err != nil {
+			return written, err
+		}
+		err = w.WriteByte('"')
+		written++
+		if err != nil {
+			return written, err
+		}
+	}
+	err := w.WriteByte('}')
+	written++
+	if err != nil {
+		return written, err
+	}
+	return written, nil
+}
+
+// writeExemplar writes the provided exemplar in OpenMetrics format to w. The
+// function returns the number of bytes written and any error encountered.
+func writeExemplar(w enhancedWriter, e *dto.Exemplar) (int, error) {
+	written := 0
+	n, err := w.WriteString(" # ")
+	written += n
+	if err != nil {
+		return written, err
+	}
+	n, err = writeOpenMetricsLabelPairs(w, e.Label, "", 0)
+	written += n
+	if err != nil {
+		return written, err
+	}
+	err = w.WriteByte(' ')
+	written++
+	if err != nil {
+		return written, err
+	}
+	n, err = writeOpenMetricsFloat(w, e.GetValue())
+	written += n
+	if err != nil {
+		return written, err
+	}
+	if e.Timestamp != nil {
+		err = w.WriteByte(' ')
+		written++
+		if err != nil {
+			return written, err
+		}
+		ts, err := ptypes.Timestamp((*e).Timestamp)
+		if err != nil {
+			return written, err
+		}
+		// TODO(beorn7): Format this directly from components of ts to
+		// avoid overflow/underflow and precision issues of the float
+		// conversion.
+		n, err = writeOpenMetricsFloat(w, float64(ts.UnixNano())/1e9)
+		written += n
+		if err != nil {
+			return written, err
+		}
+	}
+	return written, nil
+}
+
+// writeOpenMetricsFloat works like writeFloat but appends ".0" if the resulting
+// number would otherwise contain neither a "." nor an "e".
+func writeOpenMetricsFloat(w enhancedWriter, f float64) (int, error) {
+	switch {
+	case f == 1:
+		return w.WriteString("1.0")
+	case f == 0:
+		return w.WriteString("0.0")
+	case f == -1:
+		return w.WriteString("-1.0")
+	case math.IsNaN(f):
+		return w.WriteString("NaN")
+	case math.IsInf(f, +1):
+		return w.WriteString("+Inf")
+	case math.IsInf(f, -1):
+		return w.WriteString("-Inf")
+	default:
+		bp := numBufPool.Get().(*[]byte)
+		*bp = strconv.AppendFloat((*bp)[:0], f, 'g', -1, 64)
+		if !bytes.ContainsAny(*bp, "e.") {
+			*bp = append(*bp, '.', '0')
+		}
+		written, err := w.Write(*bp)
+		numBufPool.Put(bp)
+		return written, err
+	}
+}
+
+// writeUint is like writeInt just for uint64.
+func writeUint(w enhancedWriter, u uint64) (int, error) {
+	bp := numBufPool.Get().(*[]byte)
+	*bp = strconv.AppendUint((*bp)[:0], u, 10)
+	written, err := w.Write(*bp)
+	numBufPool.Put(bp)
+	return written, err
+}

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

@@ -14,9 +14,10 @@
 package expfmt
 
 import (
-	"bytes"
+	"bufio"
 	"fmt"
 	"io"
+	"io/ioutil"
 	"math"
 	"strconv"
 	"strings"
@@ -27,7 +28,7 @@ import (
 	dto "github.com/prometheus/client_model/go"
 )
 
-// enhancedWriter has all the enhanced write functions needed here. bytes.Buffer
+// enhancedWriter has all the enhanced write functions needed here. bufio.Writer
 // implements it.
 type enhancedWriter interface {
 	io.Writer
@@ -37,14 +38,13 @@ type enhancedWriter interface {
 }
 
 const (
-	initialBufSize    = 512
 	initialNumBufSize = 24
 )
 
 var (
 	bufPool = sync.Pool{
 		New: func() interface{} {
-			return bytes.NewBuffer(make([]byte, 0, initialBufSize))
+			return bufio.NewWriter(ioutil.Discard)
 		},
 	}
 	numBufPool = sync.Pool{
@@ -75,16 +75,14 @@ func MetricFamilyToText(out io.Writer, in *dto.MetricFamily) (written int, err e
 	}
 
 	// Try the interface upgrade. If it doesn't work, we'll use a
-	// bytes.Buffer from the sync.Pool and write out its content to out in a
-	// single go in the end.
+	// bufio.Writer from the sync.Pool.
 	w, ok := out.(enhancedWriter)
 	if !ok {
-		b := bufPool.Get().(*bytes.Buffer)
-		b.Reset()
+		b := bufPool.Get().(*bufio.Writer)
+		b.Reset(out)
 		w = b
 		defer func() {
-			bWritten, bErr := out.Write(b.Bytes())
-			written = bWritten
+			bErr := b.Flush()
 			if err == nil {
 				err = bErr
 			}
@@ -425,9 +423,8 @@ var (
 func writeEscapedString(w enhancedWriter, v string, includeDoubleQuote bool) (int, error) {
 	if includeDoubleQuote {
 		return quotedEscaper.WriteString(w, v)
-	} else {
-		return escaper.WriteString(w, v)
 	}
+	return escaper.WriteString(w, v)
 }
 
 // writeFloat is equivalent to fmt.Fprint with a float64 argument but hardcodes

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

@@ -325,7 +325,7 @@ func (p *TextParser) startLabelValue() stateFn {
 	// - 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 {
+			if p.currentQuantile, p.err = parseFloat(p.currentLabelPair.GetValue()); 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
@@ -337,7 +337,7 @@ func (p *TextParser) startLabelValue() stateFn {
 	// 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 {
+			if p.currentBucket, p.err = parseFloat(p.currentLabelPair.GetValue()); 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
@@ -392,7 +392,7 @@ func (p *TextParser) readingValue() stateFn {
 	if p.readTokenUntilWhitespace(); p.err != nil {
 		return nil // Unexpected end of input.
 	}
-	value, err := strconv.ParseFloat(p.currentToken.String(), 64)
+	value, err := parseFloat(p.currentToken.String())
 	if err != nil {
 		// Create a more helpful error message.
 		p.parseError(fmt.Sprintf("expected float as value, got %q", p.currentToken.String()))
@@ -755,3 +755,10 @@ func histogramMetricName(name string) string {
 		return name
 	}
 }
+
+func parseFloat(s string) (float64, error) {
+	if strings.ContainsAny(s, "pP_") {
+		return 0, fmt.Errorf("unsupported character in float")
+	}
+	return strconv.ParseFloat(s, 64)
+}

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

@@ -186,6 +186,10 @@ var durationRE = regexp.MustCompile("^([0-9]+)(y|w|d|h|m|s|ms)$")
 // ParseDuration parses a string into a time.Duration, assuming that a year
 // always has 365d, a week always has 7d, and a day always has 24h.
 func ParseDuration(durationStr string) (Duration, error) {
+	// Allow 0 without a unit.
+	if durationStr == "0" {
+		return 0, nil
+	}
 	matches := durationRE.FindStringSubmatch(durationStr)
 	if len(matches) != 3 {
 		return 0, fmt.Errorf("not a valid duration string: %q", durationStr)