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Diffstat (limited to 'vendor/github.com/prometheus/client_golang')
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diff --git a/vendor/github.com/prometheus/client_golang/LICENSE b/vendor/github.com/prometheus/client_golang/LICENSE new file mode 100644 index 000000000..261eeb9e9 --- /dev/null +++ b/vendor/github.com/prometheus/client_golang/LICENSE @@ -0,0 +1,201 @@ + Apache License + Version 2.0, January 2004 + http://www.apache.org/licenses/ + + TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION + + 1. Definitions. + + "License" shall mean the terms and conditions for use, reproduction, + and distribution as defined by Sections 1 through 9 of this document. + + "Licensor" shall mean the copyright owner or entity authorized by + the copyright owner that is granting the License. + + "Legal Entity" shall mean the union of the acting entity and all + other entities that control, are controlled by, or are under common + control with that entity. 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For the purposes + of this License, Derivative Works shall not include works that remain + separable from, or merely link (or bind by name) to the interfaces of, + the Work and Derivative Works thereof. + + "Contribution" shall mean any work of authorship, including + the original version of the Work and any modifications or additions + to that Work or Derivative Works thereof, that is intentionally + submitted to Licensor for inclusion in the Work by the copyright owner + or by an individual or Legal Entity authorized to submit on behalf of + the copyright owner. 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If You + institute patent litigation against any entity (including a + cross-claim or counterclaim in a lawsuit) alleging that the Work + or a Contribution incorporated within the Work constitutes direct + or contributory patent infringement, then any patent licenses + granted to You under this License for that Work shall terminate + as of the date such litigation is filed. + + 4. Redistribution. You may reproduce and distribute copies of the + Work or Derivative Works thereof in any medium, with or without + modifications, and in Source or Object form, provided that You + meet the following conditions: + + (a) You must give any other recipients of the Work or + Derivative Works a copy of this License; and + + (b) You must cause any modified files to carry prominent notices + stating that You changed the files; and + + (c) You must retain, in the Source form of any Derivative Works + that You distribute, all copyright, patent, trademark, and + attribution notices from the Source form of the Work, + excluding those notices that do not pertain to any part of + the Derivative Works; and + + (d) If the Work includes a "NOTICE" text file as part of its + distribution, then any Derivative Works that You distribute must + include a readable copy of the attribution notices contained + within such NOTICE file, excluding those notices that do not + pertain to any part of the Derivative Works, in at least one + of the following places: within a NOTICE text file distributed + as part of the Derivative Works; within the Source form or + documentation, if provided along with the Derivative Works; or, + within a display generated by the Derivative Works, if and + wherever such third-party notices normally appear. The contents + of the NOTICE file are for informational purposes only and + do not modify the License. You may add Your own attribution + notices within Derivative Works that You distribute, alongside + or as an addendum to the NOTICE text from the Work, provided + that such additional attribution notices cannot be construed + as modifying the License. + + You may add Your own copyright statement to Your modifications and + may provide additional or different license terms and conditions + for use, reproduction, or distribution of Your modifications, or + for any such Derivative Works as a whole, provided Your use, + reproduction, and distribution of the Work otherwise complies with + the conditions stated in this License. + + 5. Submission of Contributions. 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We also recommend that a + file or class name and description of purpose be included on the + same "printed page" as the copyright notice for easier + identification within third-party archives. + + Copyright [yyyy] [name of copyright owner] + + 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. diff --git a/vendor/github.com/prometheus/client_golang/NOTICE b/vendor/github.com/prometheus/client_golang/NOTICE new file mode 100644 index 000000000..dd878a30e --- /dev/null +++ b/vendor/github.com/prometheus/client_golang/NOTICE @@ -0,0 +1,23 @@ +Prometheus instrumentation library for Go applications +Copyright 2012-2015 The Prometheus Authors + +This product includes software developed at +SoundCloud Ltd. (http://soundcloud.com/). + + +The following components are included in this product: + +perks - a fork of https://github.com/bmizerany/perks +https://github.com/beorn7/perks +Copyright 2013-2015 Blake Mizerany, Björn Rabenstein +See https://github.com/beorn7/perks/blob/master/README.md for license details. + +Go support for Protocol Buffers - Google's data interchange format +http://github.com/golang/protobuf/ +Copyright 2010 The Go Authors +See source code for license details. + +Support for streaming Protocol Buffer messages for the Go language (golang). +https://github.com/matttproud/golang_protobuf_extensions +Copyright 2013 Matt T. Proud +Licensed under the Apache License, Version 2.0 diff --git a/vendor/github.com/prometheus/client_golang/prometheus/.gitignore b/vendor/github.com/prometheus/client_golang/prometheus/.gitignore new file mode 100644 index 000000000..3460f0346 --- /dev/null +++ b/vendor/github.com/prometheus/client_golang/prometheus/.gitignore @@ -0,0 +1 @@ +command-line-arguments.test diff --git a/vendor/github.com/prometheus/client_golang/prometheus/README.md b/vendor/github.com/prometheus/client_golang/prometheus/README.md new file mode 100644 index 000000000..44986bff0 --- /dev/null +++ b/vendor/github.com/prometheus/client_golang/prometheus/README.md @@ -0,0 +1 @@ +See [](https://godoc.org/github.com/prometheus/client_golang/prometheus). diff --git a/vendor/github.com/prometheus/client_golang/prometheus/build_info.go b/vendor/github.com/prometheus/client_golang/prometheus/build_info.go new file mode 100644 index 000000000..288f0e854 --- /dev/null +++ b/vendor/github.com/prometheus/client_golang/prometheus/build_info.go @@ -0,0 +1,29 @@ +// Copyright 2019 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. + +// +build go1.12 + +package prometheus + +import "runtime/debug" + +// readBuildInfo is a wrapper around debug.ReadBuildInfo for Go 1.12+. +func readBuildInfo() (path, version, sum string) { + path, version, sum = "unknown", "unknown", "unknown" + if bi, ok := debug.ReadBuildInfo(); ok { + path = bi.Main.Path + version = bi.Main.Version + sum = bi.Main.Sum + } + return +} diff --git a/vendor/github.com/prometheus/client_golang/prometheus/build_info_pre_1.12.go b/vendor/github.com/prometheus/client_golang/prometheus/build_info_pre_1.12.go new file mode 100644 index 000000000..6609e2877 --- /dev/null +++ b/vendor/github.com/prometheus/client_golang/prometheus/build_info_pre_1.12.go @@ -0,0 +1,22 @@ +// Copyright 2019 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. + +// +build !go1.12 + +package prometheus + +// readBuildInfo is a wrapper around debug.ReadBuildInfo for Go versions before +// 1.12. Remove this whole file once the minimum supported Go version is 1.12. +func readBuildInfo() (path, version, sum string) { + return "unknown", "unknown", "unknown" +} diff --git a/vendor/github.com/prometheus/client_golang/prometheus/collector.go b/vendor/github.com/prometheus/client_golang/prometheus/collector.go new file mode 100644 index 000000000..1e839650d --- /dev/null +++ b/vendor/github.com/prometheus/client_golang/prometheus/collector.go @@ -0,0 +1,120 @@ +// 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 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. +// +// 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. +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 + // the last descriptor has been sent. The sent descriptors fulfill the + // consistency and uniqueness requirements described in the Desc + // documentation. + // + // It is valid if one and the same Collector sends duplicate + // descriptors. Those duplicates are simply ignored. However, two + // different Collectors must not send duplicate descriptors. + // + // Sending no descriptor at all marks the Collector as “unchecked”, + // i.e. no checks will be performed at registration time, and the + // Collector may yield any Metric it sees fit in its Collect method. + // + // This method idempotently sends the same descriptors throughout the + // lifetime of the Collector. It may be called concurrently and + // therefore must be implemented in a concurrency safe way. + // + // If a Collector encounters an error while executing this method, it + // must send an invalid descriptor (created with NewInvalidDesc) to + // signal the error to the registry. + Describe(chan<- *Desc) + // Collect is called by the Prometheus registry when collecting + // metrics. The implementation sends each collected metric via the + // provided channel and returns once the last metric has been sent. The + // descriptor of each sent metric is one of those returned by Describe + // (unless the Collector is unchecked, see above). 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) +} + +// DescribeByCollect is a helper to implement the Describe method of a custom +// Collector. It collects the metrics from the provided Collector and sends +// their descriptors to the provided channel. +// +// If a Collector collects the same metrics throughout its lifetime, its +// Describe method can simply be implemented as: +// +// func (c customCollector) Describe(ch chan<- *Desc) { +// DescribeByCollect(c, ch) +// } +// +// However, this will not work if the metrics collected change dynamically over +// the lifetime of the Collector in a way that their combined set of descriptors +// changes as well. The shortcut implementation will then violate the contract +// of the Describe method. If a Collector sometimes collects no metrics at all +// (for example vectors like CounterVec, GaugeVec, etc., which only collect +// metrics after a metric with a fully specified label set has been accessed), +// it might even get registered as an unchecked Collector (cf. the Register +// method of the Registerer interface). Hence, only use this shortcut +// implementation of Describe if you are certain to fulfill the contract. +// +// The Collector example demonstrates a use of DescribeByCollect. +func DescribeByCollect(c Collector, descs chan<- *Desc) { + metrics := make(chan Metric) + go func() { + c.Collect(metrics) + close(metrics) + }() + for m := range metrics { + descs <- m.Desc() + } +} + +// selfCollector implements Collector for a single Metric so that the Metric +// collects itself. Add it as an anonymous field to a struct that implements +// Metric, and call init with the Metric itself as an argument. +type selfCollector struct { + self Metric +} + +// 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) { + c.self = self +} + +// Describe implements Collector. +func (c *selfCollector) Describe(ch chan<- *Desc) { + ch <- c.self.Desc() +} + +// Collect implements Collector. +func (c *selfCollector) Collect(ch chan<- Metric) { + ch <- c.self +} diff --git a/vendor/github.com/prometheus/client_golang/prometheus/counter.go b/vendor/github.com/prometheus/client_golang/prometheus/counter.go new file mode 100644 index 000000000..d463e36d3 --- /dev/null +++ b/vendor/github.com/prometheus/client_golang/prometheus/counter.go @@ -0,0 +1,277 @@ +// 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 prometheus + +import ( + "errors" + "math" + "sync/atomic" + + dto "github.com/prometheus/client_model/go" +) + +// Counter is a Metric that represents a single numerical value that only ever +// goes up. That implies that it cannot be used to count items whose number can +// also go down, e.g. the number of currently running goroutines. Those +// "counters" are represented by Gauges. +// +// A Counter is typically used to count requests served, tasks completed, errors +// occurred, etc. +// +// To create Counter instances, use NewCounter. +type Counter interface { + Metric + Collector + + // Inc increments the counter by 1. Use Add to increment it by arbitrary + // non-negative values. + Inc() + // Add adds the given value to the counter. It panics if the value is < + // 0. + Add(float64) +} + +// CounterOpts is an alias for Opts. See there for doc comments. +type CounterOpts Opts + +// NewCounter creates a new Counter based on the provided CounterOpts. +// +// The returned implementation tracks the counter value in two separate +// variables, a float64 and a uint64. The latter is used to track calls of the +// Inc method and calls of the Add method with a value that can be represented +// as a uint64. This allows atomic increments of the counter with optimal +// performance. (It is common to have an Inc call in very hot execution paths.) +// Both internal tracking values are added up in the Write method. This has to +// be taken into account when it comes to precision and overflow behavior. +func NewCounter(opts CounterOpts) Counter { + desc := NewDesc( + BuildFQName(opts.Namespace, opts.Subsystem, opts.Name), + opts.Help, + nil, + opts.ConstLabels, + ) + result := &counter{desc: desc, labelPairs: desc.constLabelPairs} + result.init(result) // Init self-collection. + return result +} + +type counter struct { + // valBits contains the bits of the represented float64 value, while + // valInt stores values that are exact integers. Both have to go first + // in the struct to guarantee alignment for atomic operations. + // http://golang.org/pkg/sync/atomic/#pkg-note-BUG + valBits uint64 + valInt uint64 + + selfCollector + desc *Desc + + labelPairs []*dto.LabelPair +} + +func (c *counter) Desc() *Desc { + return c.desc +} + +func (c *counter) Add(v float64) { + if v < 0 { + panic(errors.New("counter cannot decrease in value")) + } + ival := uint64(v) + if float64(ival) == v { + atomic.AddUint64(&c.valInt, ival) + return + } + + for { + oldBits := atomic.LoadUint64(&c.valBits) + newBits := math.Float64bits(math.Float64frombits(oldBits) + v) + if atomic.CompareAndSwapUint64(&c.valBits, oldBits, newBits) { + return + } + } +} + +func (c *counter) Inc() { + atomic.AddUint64(&c.valInt, 1) +} + +func (c *counter) Write(out *dto.Metric) error { + fval := math.Float64frombits(atomic.LoadUint64(&c.valBits)) + ival := atomic.LoadUint64(&c.valInt) + val := fval + float64(ival) + + return populateMetric(CounterValue, val, c.labelPairs, out) +} + +// CounterVec is a Collector that bundles a set of Counters that all share the +// same Desc, but have different values for their variable labels. This is used +// if you want to count the same thing partitioned by various dimensions +// (e.g. number of HTTP requests, partitioned by response code and +// method). Create instances with NewCounterVec. +type CounterVec struct { + *metricVec +} + +// NewCounterVec creates a new CounterVec based on the provided CounterOpts and +// partitioned by the given label names. +func NewCounterVec(opts CounterOpts, labelNames []string) *CounterVec { + desc := NewDesc( + BuildFQName(opts.Namespace, opts.Subsystem, opts.Name), + opts.Help, + labelNames, + opts.ConstLabels, + ) + return &CounterVec{ + metricVec: newMetricVec(desc, func(lvs ...string) Metric { + if len(lvs) != len(desc.variableLabels) { + panic(makeInconsistentCardinalityError(desc.fqName, desc.variableLabels, lvs)) + } + result := &counter{desc: desc, labelPairs: makeLabelPairs(desc, lvs)} + result.init(result) // Init self-collection. + return result + }), + } +} + +// GetMetricWithLabelValues returns the Counter for the given slice of label +// values (same order as the VariableLabels in Desc). If that combination of +// label values is accessed for the first time, a new Counter is created. +// +// It is possible to call this method without using the returned Counter to only +// create the new Counter but leave it at its starting value 0. See also the +// SummaryVec example. +// +// Keeping the Counter for later use is possible (and should be considered if +// performance is critical), but keep in mind that Reset, DeleteLabelValues and +// Delete can be used to delete the Counter from the CounterVec. In that case, +// the Counter will still exist, but it will not be exported anymore, even if a +// Counter with the same label values is created later. +// +// An error is returned if the number of label values is not the same as the +// number of VariableLabels in Desc (minus any curried labels). +// +// Note that for more than one label value, this method is prone to mistakes +// caused by an incorrect order of arguments. Consider GetMetricWith(Labels) as +// an alternative to avoid that type of mistake. For higher label numbers, the +// latter has a much more readable (albeit more verbose) syntax, but it comes +// with a performance overhead (for creating and processing the Labels map). +// See also the GaugeVec example. +func (v *CounterVec) GetMetricWithLabelValues(lvs ...string) (Counter, error) { + metric, err := v.metricVec.getMetricWithLabelValues(lvs...) + if metric != nil { + return metric.(Counter), err + } + return nil, err +} + +// GetMetricWith returns the Counter for the given Labels map (the label names +// must match those of the VariableLabels in Desc). If that label map is +// accessed for the first time, a new Counter is created. Implications of +// creating a Counter without using it and keeping the Counter for later use are +// the same as for GetMetricWithLabelValues. +// +// An error is returned if the number and names of the Labels are inconsistent +// with those of the VariableLabels in Desc (minus any curried labels). +// +// This method is used for the same purpose as +// GetMetricWithLabelValues(...string). See there for pros and cons of the two +// methods. +func (v *CounterVec) GetMetricWith(labels Labels) (Counter, error) { + metric, err := v.metricVec.getMetricWith(labels) + if metric != nil { + return metric.(Counter), err + } + return nil, err +} + +// WithLabelValues works as GetMetricWithLabelValues, but panics where +// GetMetricWithLabelValues would have returned an error. Not returning an +// error allows shortcuts like +// myVec.WithLabelValues("404", "GET").Add(42) +func (v *CounterVec) WithLabelValues(lvs ...string) Counter { + c, err := v.GetMetricWithLabelValues(lvs...) + if err != nil { + panic(err) + } + return c +} + +// With works as GetMetricWith, but panics where GetMetricWithLabels would have +// returned an error. Not returning an error allows shortcuts like +// myVec.With(prometheus.Labels{"code": "404", "method": "GET"}).Add(42) +func (v *CounterVec) With(labels Labels) Counter { + c, err := v.GetMetricWith(labels) + if err != nil { + panic(err) + } + return c +} + +// CurryWith returns a vector curried with the provided labels, i.e. the +// returned vector has those labels pre-set for all labeled operations performed +// on it. The cardinality of the curried vector is reduced accordingly. The +// order of the remaining labels stays the same (just with the curried labels +// taken out of the sequence – which is relevant for the +// (GetMetric)WithLabelValues methods). It is possible to curry a curried +// vector, but only with labels not yet used for currying before. +// +// The metrics contained in the CounterVec are shared between the curried and +// uncurried vectors. They are just accessed differently. Curried and uncurried +// vectors behave identically in terms of collection. Only one must be +// registered with a given registry (usually the uncurried version). The Reset +// method deletes all metrics, even if called on a curried vector. +func (v *CounterVec) CurryWith(labels Labels) (*CounterVec, error) { + vec, err := v.curryWith(labels) + if vec != nil { + return &CounterVec{vec}, err + } + return nil, err +} + +// MustCurryWith works as CurryWith but panics where CurryWith would have +// returned an error. +func (v *CounterVec) MustCurryWith(labels Labels) *CounterVec { + vec, err := v.CurryWith(labels) + if err != nil { + panic(err) + } + return vec +} + +// CounterFunc is a Counter whose value is determined at collect time by calling a +// provided function. +// +// To create CounterFunc instances, use NewCounterFunc. +type CounterFunc interface { + Metric + Collector +} + +// NewCounterFunc creates a new CounterFunc based on the provided +// CounterOpts. The value reported is determined by calling the given function +// from within the Write method. Take into account that metric collection may +// happen concurrently. If that results in concurrent calls to Write, like in +// the case where a CounterFunc is directly registered with Prometheus, the +// provided function must be concurrency-safe. The function should also honor +// the contract for a Counter (values only go up, not down), but compliance will +// not be checked. +func NewCounterFunc(opts CounterOpts, function func() float64) CounterFunc { + return newValueFunc(NewDesc( + BuildFQName(opts.Namespace, opts.Subsystem, opts.Name), + opts.Help, + nil, + opts.ConstLabels, + ), CounterValue, function) +} diff --git a/vendor/github.com/prometheus/client_golang/prometheus/desc.go b/vendor/github.com/prometheus/client_golang/prometheus/desc.go new file mode 100644 index 000000000..1d034f871 --- /dev/null +++ b/vendor/github.com/prometheus/client_golang/prometheus/desc.go @@ -0,0 +1,184 @@ +// 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 ( + "errors" + "fmt" + "sort" + "strings" + + "github.com/golang/protobuf/proto" + "github.com/prometheus/common/model" + + dto "github.com/prometheus/client_model/go" +) + +// Desc is the descriptor used by every Prometheus Metric. It is essentially +// the immutable meta-data of a Metric. The normal Metric implementations +// included in this package manage their Desc under the hood. Users only have to +// deal with Desc if they use advanced features like the ExpvarCollector or +// custom Collectors and Metrics. +// +// Descriptors registered with the same registry have to fulfill certain +// consistency and uniqueness criteria if they share the same fully-qualified +// name: They must have the same help string and the same label names (aka label +// dimensions) in each, constLabels and variableLabels, but they must differ in +// the values of the constLabels. +// +// Descriptors that share the same fully-qualified names and the same label +// values of their constLabels are considered equal. +// +// Use NewDesc to create new Desc instances. +type Desc struct { + // fqName has been built from Namespace, Subsystem, and Name. + fqName string + // help provides some helpful information about this metric. + help string + // constLabelPairs contains precalculated DTO label pairs based on + // the constant labels. + constLabelPairs []*dto.LabelPair + // VariableLabels contains names of labels for which the metric + // maintains variable values. + variableLabels []string + // id is a hash of the values of the ConstLabels and fqName. This + // must be unique among all registered descriptors and can therefore be + // used as an identifier of the descriptor. + id uint64 + // dimHash is a hash of the label names (preset and variable) and the + // 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 + // registration time. + err error +} + +// NewDesc allocates and initializes a new Desc. Errors are recorded in the Desc +// and will be reported on registration time. variableLabels and constLabels can +// be nil if no such labels should be set. fqName must not be empty. +// +// variableLabels only contain the label names. Their label values are variable +// and therefore not part of the Desc. (They are managed within the Metric.) +// +// For constLabels, the label values are constant. Therefore, they are fully +// specified in the Desc. See the Collector example for a usage pattern. +func NewDesc(fqName, help string, variableLabels []string, constLabels Labels) *Desc { + d := &Desc{ + fqName: fqName, + help: help, + variableLabels: variableLabels, + } + if !model.IsValidMetricName(model.LabelValue(fqName)) { + d.err = fmt.Errorf("%q is not a valid metric name", fqName) + return d + } + // labelValues contains the label values of const labels (in order of + // their sorted label names) plus the fqName (at position 0). + labelValues := make([]string, 1, len(constLabels)+1) + labelValues[0] = fqName + labelNames := make([]string, 0, len(constLabels)+len(variableLabels)) + labelNameSet := map[string]struct{}{} + // First add only the const label names and sort them... + for labelName := range constLabels { + if !checkLabelName(labelName) { + d.err = fmt.Errorf("%q is not a valid label name for metric %q", labelName, fqName) + return d + } + labelNames = append(labelNames, labelName) + labelNameSet[labelName] = struct{}{} + } + sort.Strings(labelNames) + // ... so that we can now add const label values in the order of their names. + for _, labelName := range labelNames { + labelValues = append(labelValues, constLabels[labelName]) + } + // Validate the const label values. They can't have a wrong cardinality, so + // use in len(labelValues) as expectedNumberOfValues. + if err := validateLabelValues(labelValues, len(labelValues)); err != nil { + d.err = err + return d + } + // Now add the variable label names, but prefix them with something that + // cannot be in a regular label name. That prevents matching the label + // dimension with a different mix between preset and variable labels. + for _, labelName := range variableLabels { + if !checkLabelName(labelName) { + d.err = fmt.Errorf("%q is not a valid label name for metric %q", labelName, fqName) + return d + } + labelNames = append(labelNames, "$"+labelName) + labelNameSet[labelName] = struct{}{} + } + if len(labelNames) != len(labelNameSet) { + d.err = errors.New("duplicate label names") + return d + } + + vh := hashNew() + for _, val := range labelValues { + vh = hashAdd(vh, val) + vh = hashAddByte(vh, separatorByte) + } + d.id = vh + // 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) + for _, labelName := range labelNames { + lh = hashAdd(lh, labelName) + lh = hashAddByte(lh, separatorByte) + } + d.dimHash = lh + + d.constLabelPairs = make([]*dto.LabelPair, 0, len(constLabels)) + for n, v := range constLabels { + d.constLabelPairs = append(d.constLabelPairs, &dto.LabelPair{ + Name: proto.String(n), + Value: proto.String(v), + }) + } + sort.Sort(labelPairSorter(d.constLabelPairs)) + return d +} + +// NewInvalidDesc returns an invalid descriptor, i.e. a descriptor with the +// provided error set. If a collector returning such a descriptor is registered, +// registration will fail with the provided error. NewInvalidDesc can be used by +// a Collector to signal inability to describe itself. +func NewInvalidDesc(err error) *Desc { + return &Desc{ + err: err, + } +} + +func (d *Desc) String() string { + lpStrings := make([]string, 0, len(d.constLabelPairs)) + for _, lp := range d.constLabelPairs { + lpStrings = append( + lpStrings, + fmt.Sprintf("%s=%q", lp.GetName(), lp.GetValue()), + ) + } + return fmt.Sprintf( + "Desc{fqName: %q, help: %q, constLabels: {%s}, variableLabels: %v}", + d.fqName, + d.help, + strings.Join(lpStrings, ","), + d.variableLabels, + ) +} diff --git a/vendor/github.com/prometheus/client_golang/prometheus/doc.go b/vendor/github.com/prometheus/client_golang/prometheus/doc.go new file mode 100644 index 000000000..01977de66 --- /dev/null +++ b/vendor/github.com/prometheus/client_golang/prometheus/doc.go @@ -0,0 +1,200 @@ +// 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 prometheus is the core instrumentation package. It 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). There is +// also a sub-package promauto, which provides metrics constructors with +// automatic registration. +// +// All exported functions and methods are safe to be used concurrently unless +// specified otherwise. +// +// A Basic Example +// +// As a starting point, a very basic usage example: +// +// package main +// +// import ( +// "log" +// "net/http" +// +// "github.com/prometheus/client_golang/prometheus" +// "github.com/prometheus/client_golang/prometheus/promhttp" +// ) +// +// var ( +// cpuTemp = prometheus.NewGauge(prometheus.GaugeOpts{ +// 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"}, +// ) +// ) +// +// 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() +// +// // 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()) +// log.Fatal(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. +// +// Metrics +// +// The number of exported identifiers in this package might appear a bit +// overwhelming. However, in addition to the basic plumbing shown in the example +// above, you only need to understand the different metric types and their +// vector versions for basic usage. Furthermore, if you are not concerned with +// fine-grained control of when and how to register metrics with the registry, +// have a look at the promauto package, which will effectively allow you to +// ignore registration altogether in simple cases. +// +// 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 +// metric vectors. The fundamental types are GaugeVec, CounterVec, SummaryVec, +// HistogramVec, and UntypedVec. +// +// 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. +// +// To create instances of Metrics and their vector versions, you need a suitable +// …Opts struct, i.e. GaugeOpts, CounterOpts, SummaryOpts, HistogramOpts, or +// UntypedOpts. +// +// Custom Collectors and constant Metrics +// +// 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). +// +// 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. Alternatively, you +// could return no Desc at all, which will mark the Collector “unchecked”. No +// checks are performed at registration time, but metric consistency will still +// be ensured at scrape time, i.e. any inconsistencies will lead to scrape +// errors. Thus, with unchecked Collectors, the responsibility to not collect +// metrics that lead to inconsistencies in the total scrape result lies with the +// implementer of the Collector. While this is not a desirable state, it is +// sometimes necessary. The typical use case is a situation where the exact +// metrics to be returned by a Collector cannot be predicted at registration +// time, but the implementer has sufficient knowledge of the whole system to +// guarantee metric consistency. +// +// The Collector example illustrates the use case. You can also look at the +// source code of the processCollector (mirroring process metrics), the +// goCollector (mirroring Go metrics), or the expvarCollector (mirroring expvar +// metrics) as examples that are used in this package 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 DefaultRegisterer variable. With NewRegistry, you +// can create a custom registry, or you can even implement the Registerer or +// Gatherer interfaces yourself. The methods Register and Unregister work in 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 DefaultRegisterer. 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 DefaultRegisterer comes registered with a Collector for Go +// runtime metrics (via NewGoCollector) and a Collector for process metrics (via +// NewProcessCollector). With a custom registry, you are in control and decide +// yourself about the Collectors to register. +// +// 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. +// +// Pushing to the Pushgateway +// +// Function for pushing to the Pushgateway can be found in the push sub-package. +// +// Graphite Bridge +// +// Functions and examples to push metrics from a Gatherer to Graphite can be +// found in the graphite sub-package. +// +// Other Means of Exposition +// +// More ways of exposing metrics can easily be added by following the approaches +// of the existing implementations. +package prometheus diff --git a/vendor/github.com/prometheus/client_golang/prometheus/expvar_collector.go b/vendor/github.com/prometheus/client_golang/prometheus/expvar_collector.go new file mode 100644 index 000000000..18a99d5fa --- /dev/null +++ b/vendor/github.com/prometheus/client_golang/prometheus/expvar_collector.go @@ -0,0 +1,119 @@ +// 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 prometheus + +import ( + "encoding/json" + "expvar" +) + +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. +// +// The exports map has the following meaning: +// +// The keys in the map correspond to expvar keys, i.e. for every expvar key you +// want to export as Prometheus metric, you need an entry in the exports +// map. The descriptor mapped to each key describes how to export the expvar +// value. It defines the name and the help string of the Prometheus metric +// proxying the expvar value. The type will always be Untyped. +// +// For descriptors without variable labels, the expvar value must be a number or +// a bool. The number is then directly exported as the Prometheus sample +// value. (For a bool, 'false' translates to 0 and 'true' to 1). Expvar values +// that are not numbers or bools are silently ignored. +// +// If the descriptor has one variable label, the expvar value must be an expvar +// map. The keys in the expvar map become the various values of the one +// Prometheus label. The values in the expvar map must be numbers or bools again +// as above. +// +// For descriptors with more than one variable label, the expvar must be a +// nested expvar map, i.e. where the values of the topmost map are maps again +// etc. until a depth is reached that corresponds to the number of labels. The +// leaves of that structure must be numbers or bools as above to serve as the +// sample values. +// +// Anything that does not fit into the scheme above is silently ignored. +func NewExpvarCollector(exports map[string]*Desc) Collector { + return &expvarCollector{ + exports: exports, + } +} + +// Describe implements Collector. +func (e *expvarCollector) Describe(ch chan<- *Desc) { + for _, desc := range e.exports { + ch <- desc + } +} + +// Collect implements Collector. +func (e *expvarCollector) Collect(ch chan<- Metric) { + for name, desc := range e.exports { + var m Metric + expVar := expvar.Get(name) + if expVar == nil { + continue + } + var v interface{} + labels := make([]string, len(desc.variableLabels)) + if err := json.Unmarshal([]byte(expVar.String()), &v); err != nil { + ch <- NewInvalidMetric(desc, err) + continue + } + var processValue func(v interface{}, i int) + processValue = func(v interface{}, i int) { + if i >= len(labels) { + copiedLabels := append(make([]string, 0, len(labels)), labels...) + switch v := v.(type) { + case float64: + m = MustNewConstMetric(desc, UntypedValue, v, copiedLabels...) + case bool: + if v { + m = MustNewConstMetric(desc, UntypedValue, 1, copiedLabels...) + } else { + m = MustNewConstMetric(desc, UntypedValue, 0, copiedLabels...) + } + default: + return + } + ch <- m + return + } + vm, ok := v.(map[string]interface{}) + if !ok { + return + } + for lv, val := range vm { + labels[i] = lv + processValue(val, i+1) + } + } + processValue(v, 0) + } +} diff --git a/vendor/github.com/prometheus/client_golang/prometheus/fnv.go b/vendor/github.com/prometheus/client_golang/prometheus/fnv.go new file mode 100644 index 000000000..3d383a735 --- /dev/null +++ b/vendor/github.com/prometheus/client_golang/prometheus/fnv.go @@ -0,0 +1,42 @@ +// Copyright 2018 The Prometheus Authors +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package prometheus + +// Inline and byte-free variant of hash/fnv's fnv64a. + +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 +} diff --git a/vendor/github.com/prometheus/client_golang/prometheus/gauge.go b/vendor/github.com/prometheus/client_golang/prometheus/gauge.go new file mode 100644 index 000000000..71d406bd9 --- /dev/null +++ b/vendor/github.com/prometheus/client_golang/prometheus/gauge.go @@ -0,0 +1,286 @@ +// 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 prometheus + +import ( + "math" + "sync/atomic" + "time" + + dto "github.com/prometheus/client_model/go" +) + +// Gauge is a Metric that represents a single numerical value that can +// arbitrarily go up and down. +// +// A Gauge is typically used for measured values like temperatures or current +// memory usage, but also "counts" that can go up and down, like the number of +// running goroutines. +// +// To create Gauge instances, use NewGauge. +type Gauge interface { + Metric + Collector + + // Set sets the Gauge to an arbitrary value. + Set(float64) + // Inc increments the Gauge by 1. Use Add to increment it by arbitrary + // values. + Inc() + // Dec decrements the Gauge by 1. Use Sub to decrement it by arbitrary + // values. + Dec() + // Add adds the given value to the Gauge. (The value can be negative, + // resulting in a decrease of the Gauge.) + Add(float64) + // Sub subtracts the given value from the Gauge. (The value can be + // negative, resulting in an increase of the Gauge.) + Sub(float64) + + // SetToCurrentTime sets the Gauge to the current Unix time in seconds. + SetToCurrentTime() +} + +// GaugeOpts is an alias for Opts. See there for doc comments. +type GaugeOpts Opts + +// NewGauge creates a new Gauge based on the provided GaugeOpts. +// +// The returned implementation is optimized for a fast Set method. If you have a +// choice for managing the value of a Gauge via Set vs. Inc/Dec/Add/Sub, pick +// the former. For example, the Inc method of the returned Gauge is slower than +// the Inc method of a Counter returned by NewCounter. This matches the typical +// scenarios for Gauges and Counters, where the former tends to be Set-heavy and +// the latter Inc-heavy. +func NewGauge(opts GaugeOpts) Gauge { + desc := NewDesc( + BuildFQName(opts.Namespace, opts.Subsystem, opts.Name), + opts.Help, + nil, + opts.ConstLabels, + ) + result := &gauge{desc: desc, labelPairs: desc.constLabelPairs} + result.init(result) // Init self-collection. + return result +} + +type gauge struct { + // valBits contains the bits of the represented float64 value. It has + // to go first in the struct to guarantee alignment for atomic + // operations. http://golang.org/pkg/sync/atomic/#pkg-note-BUG + valBits uint64 + + selfCollector + + desc *Desc + labelPairs []*dto.LabelPair +} + +func (g *gauge) Desc() *Desc { + return g.desc +} + +func (g *gauge) Set(val float64) { + atomic.StoreUint64(&g.valBits, math.Float64bits(val)) +} + +func (g *gauge) SetToCurrentTime() { + g.Set(float64(time.Now().UnixNano()) / 1e9) +} + +func (g *gauge) Inc() { + g.Add(1) +} + +func (g *gauge) Dec() { + g.Add(-1) +} + +func (g *gauge) Add(val float64) { + for { + oldBits := atomic.LoadUint64(&g.valBits) + newBits := math.Float64bits(math.Float64frombits(oldBits) + val) + if atomic.CompareAndSwapUint64(&g.valBits, oldBits, newBits) { + return + } + } +} + +func (g *gauge) Sub(val float64) { + g.Add(val * -1) +} + +func (g *gauge) Write(out *dto.Metric) error { + val := math.Float64frombits(atomic.LoadUint64(&g.valBits)) + return populateMetric(GaugeValue, val, g.labelPairs, out) +} + +// GaugeVec is a Collector that bundles a set of Gauges that all share the same +// Desc, but have different values for their variable labels. This is used if +// you want to count the same thing partitioned by various dimensions +// (e.g. number of operations queued, partitioned by user and operation +// type). Create instances with NewGaugeVec. +type GaugeVec struct { + *metricVec +} + +// NewGaugeVec creates a new GaugeVec based on the provided GaugeOpts and +// partitioned by the given label names. +func NewGaugeVec(opts GaugeOpts, labelNames []string) *GaugeVec { + desc := NewDesc( + BuildFQName(opts.Namespace, opts.Subsystem, opts.Name), + opts.Help, + labelNames, + opts.ConstLabels, + ) + return &GaugeVec{ + metricVec: newMetricVec(desc, func(lvs ...string) Metric { + if len(lvs) != len(desc.variableLabels) { + panic(makeInconsistentCardinalityError(desc.fqName, desc.variableLabels, lvs)) + } + result := &gauge{desc: desc, labelPairs: makeLabelPairs(desc, lvs)} + result.init(result) // Init self-collection. + return result + }), + } +} + +// GetMetricWithLabelValues returns the Gauge for the given slice of label +// values (same order as the VariableLabels in Desc). If that combination of +// label values is accessed for the first time, a new Gauge is created. +// +// It is possible to call this method without using the returned Gauge to only +// create the new Gauge but leave it at its starting value 0. See also the +// SummaryVec example. +// +// Keeping the Gauge for later use is possible (and should be considered if +// performance is critical), but keep in mind that Reset, DeleteLabelValues and +// Delete can be used to delete the Gauge from the GaugeVec. In that case, the +// Gauge will still exist, but it will not be exported anymore, even if a +// Gauge with the same label values is created later. See also the CounterVec +// example. +// +// An error is returned if the number of label values is not the same as the +// number of VariableLabels in Desc (minus any curried labels). +// +// Note that for more than one label value, this method is prone to mistakes +// caused by an incorrect order of arguments. Consider GetMetricWith(Labels) as +// an alternative to avoid that type of mistake. For higher label numbers, the +// latter has a much more readable (albeit more verbose) syntax, but it comes +// with a performance overhead (for creating and processing the Labels map). +func (v *GaugeVec) GetMetricWithLabelValues(lvs ...string) (Gauge, error) { + metric, err := v.metricVec.getMetricWithLabelValues(lvs...) + if metric != nil { + return metric.(Gauge), err + } + return nil, err +} + +// GetMetricWith returns the Gauge for the given Labels map (the label names +// must match those of the VariableLabels in Desc). If that label map is +// accessed for the first time, a new Gauge is created. Implications of +// creating a Gauge without using it and keeping the Gauge for later use are +// the same as for GetMetricWithLabelValues. +// +// An error is returned if the number and names of the Labels are inconsistent +// with those of the VariableLabels in Desc (minus any curried labels). +// +// This method is used for the same purpose as +// GetMetricWithLabelValues(...string). See there for pros and cons of the two +// methods. +func (v *GaugeVec) GetMetricWith(labels Labels) (Gauge, error) { + metric, err := v.metricVec.getMetricWith(labels) + if metric != nil { + return metric.(Gauge), err + } + return nil, err +} + +// WithLabelValues works as GetMetricWithLabelValues, but panics where +// GetMetricWithLabelValues would have returned an error. Not returning an +// error allows shortcuts like +// myVec.WithLabelValues("404", "GET").Add(42) +func (v *GaugeVec) WithLabelValues(lvs ...string) Gauge { + g, err := v.GetMetricWithLabelValues(lvs...) + if err != nil { + panic(err) + } + return g +} + +// With works as GetMetricWith, but panics where GetMetricWithLabels would have +// returned an error. Not returning an error allows shortcuts like +// myVec.With(prometheus.Labels{"code": "404", "method": "GET"}).Add(42) +func (v *GaugeVec) With(labels Labels) Gauge { + g, err := v.GetMetricWith(labels) + if err != nil { + panic(err) + } + return g +} + +// CurryWith returns a vector curried with the provided labels, i.e. the +// returned vector has those labels pre-set for all labeled operations performed +// on it. The cardinality of the curried vector is reduced accordingly. The +// order of the remaining labels stays the same (just with the curried labels +// taken out of the sequence – which is relevant for the +// (GetMetric)WithLabelValues methods). It is possible to curry a curried +// vector, but only with labels not yet used for currying before. +// +// The metrics contained in the GaugeVec are shared between the curried and +// uncurried vectors. They are just accessed differently. Curried and uncurried +// vectors behave identically in terms of collection. Only one must be +// registered with a given registry (usually the uncurried version). The Reset +// method deletes all metrics, even if called on a curried vector. +func (v *GaugeVec) CurryWith(labels Labels) (*GaugeVec, error) { + vec, err := v.curryWith(labels) + if vec != nil { + return &GaugeVec{vec}, err + } + return nil, err +} + +// MustCurryWith works as CurryWith but panics where CurryWith would have +// returned an error. +func (v *GaugeVec) MustCurryWith(labels Labels) *GaugeVec { + vec, err := v.CurryWith(labels) + if err != nil { + panic(err) + } + return vec +} + +// GaugeFunc is a Gauge whose value is determined at collect time by calling a +// provided function. +// +// To create GaugeFunc instances, use NewGaugeFunc. +type GaugeFunc interface { + Metric + Collector +} + +// NewGaugeFunc creates a new GaugeFunc based on the provided GaugeOpts. The +// value reported is determined by calling the given function from within the +// Write method. Take into account that metric collection may happen +// concurrently. If that results in concurrent calls to Write, like in the case +// where a GaugeFunc is directly registered with Prometheus, the provided +// function must be concurrency-safe. +func NewGaugeFunc(opts GaugeOpts, function func() float64) GaugeFunc { + return newValueFunc(NewDesc( + BuildFQName(opts.Namespace, opts.Subsystem, opts.Name), + opts.Help, + nil, + opts.ConstLabels, + ), GaugeValue, function) +} diff --git a/vendor/github.com/prometheus/client_golang/prometheus/go_collector.go b/vendor/github.com/prometheus/client_golang/prometheus/go_collector.go new file mode 100644 index 000000000..dc9247fed --- /dev/null +++ b/vendor/github.com/prometheus/client_golang/prometheus/go_collector.go @@ -0,0 +1,396 @@ +// Copyright 2018 The Prometheus Authors +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package prometheus + +import ( + "runtime" + "runtime/debug" + "sync" + "time" +) + +type goCollector struct { + goroutinesDesc *Desc + threadsDesc *Desc + gcDesc *Desc + goInfoDesc *Desc + + // ms... are memstats related. + msLast *runtime.MemStats // Previously collected memstats. + msLastTimestamp time.Time + msMtx sync.Mutex // Protects msLast and msLastTimestamp. + msMetrics memStatsMetrics + msRead func(*runtime.MemStats) // For mocking in tests. + msMaxWait time.Duration // Wait time for fresh memstats. + msMaxAge time.Duration // Maximum allowed age of old memstats. +} + +// NewGoCollector returns a collector that exports metrics about the current Go +// process. This includes memory stats. To collect those, runtime.ReadMemStats +// is called. This requires to “stop the world”, which usually only happens for +// garbage collection (GC). Take the following implications into account when +// deciding whether to use the Go collector: +// +// 1. The performance impact of stopping the world is the more relevant the more +// frequently metrics are collected. However, with Go1.9 or later the +// stop-the-world time per metrics collection is very short (~25µs) so that the +// performance impact will only matter in rare cases. However, with older Go +// versions, the stop-the-world duration depends on the heap size and can be +// quite significant (~1.7 ms/GiB as per +// https://go-review.googlesource.com/c/go/+/34937). +// +// 2. During an ongoing GC, nothing else can stop the world. Therefore, if the +// metrics collection happens to coincide with GC, it will only complete after +// GC has finished. Usually, GC is fast enough to not cause problems. However, +// with a very large heap, GC might take multiple seconds, which is enough to +// cause scrape timeouts in common setups. To avoid this problem, the Go +// collector will use the memstats from a previous collection if +// runtime.ReadMemStats takes more than 1s. However, if there are no previously +// collected memstats, or their collection is more than 5m ago, the collection +// will block until runtime.ReadMemStats succeeds. (The problem might be solved +// in Go1.13, see https://github.com/golang/go/issues/19812 for the related Go +// issue.) +func NewGoCollector() Collector { + return &goCollector{ + goroutinesDesc: NewDesc( + "go_goroutines", + "Number of goroutines that currently exist.", + nil, nil), + threadsDesc: NewDesc( + "go_threads", + "Number of OS threads created.", + nil, nil), + gcDesc: NewDesc( + "go_gc_duration_seconds", + "A summary of the GC invocation durations.", + nil, nil), + goInfoDesc: NewDesc( + "go_info", + "Information about the Go environment.", + nil, Labels{"version": runtime.Version()}), + msLast: &runtime.MemStats{}, + msRead: runtime.ReadMemStats, + msMaxWait: time.Second, + msMaxAge: 5 * time.Minute, + msMetrics: 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 from system.", + 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"), + "Number of heap bytes released to OS.", + nil, nil, + ), + eval: func(ms *runtime.MemStats) float64 { return float64(ms.HeapReleased) }, + valType: GaugeValue, + }, { + 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, + }, { + desc: NewDesc( + memstatNamespace("gc_cpu_fraction"), + "The fraction of this program's available CPU time used by the GC since the program started.", + nil, nil, + ), + eval: func(ms *runtime.MemStats) float64 { return ms.GCCPUFraction }, + valType: GaugeValue, + }, + }, + } +} + +func memstatNamespace(s string) string { + return "go_memstats_" + s +} + +// Describe returns all descriptions of the collector. +func (c *goCollector) Describe(ch chan<- *Desc) { + ch <- c.goroutinesDesc + ch <- c.threadsDesc + ch <- c.gcDesc + ch <- c.goInfoDesc + for _, i := range c.msMetrics { + ch <- i.desc + } +} + +// Collect returns the current state of all metrics of the collector. +func (c *goCollector) Collect(ch chan<- Metric) { + var ( + ms = &runtime.MemStats{} + done = make(chan struct{}) + ) + // Start reading memstats first as it might take a while. + go func() { + c.msRead(ms) + c.msMtx.Lock() + c.msLast = ms + c.msLastTimestamp = time.Now() + c.msMtx.Unlock() + close(done) + }() + + ch <- MustNewConstMetric(c.goroutinesDesc, GaugeValue, float64(runtime.NumGoroutine())) + n, _ := runtime.ThreadCreateProfile(nil) + ch <- MustNewConstMetric(c.threadsDesc, GaugeValue, float64(n)) + + var stats debug.GCStats + stats.PauseQuantiles = make([]time.Duration, 5) + debug.ReadGCStats(&stats) + + quantiles := make(map[float64]float64) + for idx, pq := range stats.PauseQuantiles[1:] { + quantiles[float64(idx+1)/float64(len(stats.PauseQuantiles)-1)] = pq.Seconds() + } + quantiles[0.0] = stats.PauseQuantiles[0].Seconds() + ch <- MustNewConstSummary(c.gcDesc, uint64(stats.NumGC), stats.PauseTotal.Seconds(), quantiles) + + ch <- MustNewConstMetric(c.goInfoDesc, GaugeValue, 1) + + timer := time.NewTimer(c.msMaxWait) + select { + case <-done: // Our own ReadMemStats succeeded in time. Use it. + timer.Stop() // Important for high collection frequencies to not pile up timers. + c.msCollect(ch, ms) + return + case <-timer.C: // Time out, use last memstats if possible. Continue below. + } + c.msMtx.Lock() + if time.Since(c.msLastTimestamp) < c.msMaxAge { + // Last memstats are recent enough. Collect from them under the lock. + c.msCollect(ch, c.msLast) + c.msMtx.Unlock() + return + } + // If we are here, the last memstats are too old or don't exist. We have + // to wait until our own ReadMemStats finally completes. For that to + // happen, we have to release the lock. + c.msMtx.Unlock() + <-done + c.msCollect(ch, ms) +} + +func (c *goCollector) msCollect(ch chan<- Metric, ms *runtime.MemStats) { + for _, i := range c.msMetrics { + 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 +} + +// NewBuildInfoCollector returns a collector collecting a single metric +// "go_build_info" with the constant value 1 and three labels "path", "version", +// and "checksum". Their label values contain the main module path, version, and +// checksum, respectively. The labels will only have meaningful values if the +// binary is built with Go module support and from source code retrieved from +// the source repository (rather than the local file system). This is usually +// accomplished by building from outside of GOPATH, specifying the full address +// of the main package, e.g. "GO111MODULE=on go run +// github.com/prometheus/client_golang/examples/random". If built without Go +// module support, all label values will be "unknown". If built with Go module +// support but using the source code from the local file system, the "path" will +// be set appropriately, but "checksum" will be empty and "version" will be +// "(devel)". +// +// This collector uses only the build information for the main module. See +// https://github.com/povilasv/prommod for an example of a collector for the +// module dependencies. +func NewBuildInfoCollector() Collector { + path, version, sum := readBuildInfo() + c := &selfCollector{MustNewConstMetric( + NewDesc( + "go_build_info", + "Build information about the main Go module.", + nil, Labels{"path": path, "version": version, "checksum": sum}, + ), + GaugeValue, 1)} + c.init(c.self) + return c +} diff --git a/vendor/github.com/prometheus/client_golang/prometheus/histogram.go b/vendor/github.com/prometheus/client_golang/prometheus/histogram.go new file mode 100644 index 000000000..d7ea67bd2 --- /dev/null +++ b/vendor/github.com/prometheus/client_golang/prometheus/histogram.go @@ -0,0 +1,586 @@ +// 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. + +package prometheus + +import ( + "fmt" + "math" + "runtime" + "sort" + "sync" + "sync/atomic" + + "github.com/golang/protobuf/proto" + + dto "github.com/prometheus/client_model/go" +) + +// A Histogram counts individual observations from an event or sample stream in +// configurable buckets. Similar to a summary, it also provides a sum of +// observations and an observation count. +// +// On the Prometheus server, quantiles can be calculated from a Histogram using +// the histogram_quantile function in the query language. +// +// Note that Histograms, in contrast to Summaries, can be aggregated with the +// Prometheus query language (see the documentation for detailed +// procedures). However, Histograms require the user to pre-define suitable +// buckets, and they are in general less accurate. The Observe method of a +// Histogram has a very low performance overhead in comparison with the Observe +// method of a Summary. +// +// To create Histogram instances, use NewHistogram. +type Histogram interface { + Metric + Collector + + // Observe adds a single observation to the histogram. + 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 = []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, + ) +) + +// LinearBuckets creates 'count' buckets, each 'width' wide, where the lowest +// bucket has an upper bound of 'start'. The final +Inf bucket is not counted +// and not included in the returned slice. The returned slice is meant to be +// used for the Buckets field of HistogramOpts. +// +// The function panics if 'count' is zero or negative. +func LinearBuckets(start, width float64, count int) []float64 { + if count < 1 { + panic("LinearBuckets needs a positive count") + } + buckets := make([]float64, count) + for i := range buckets { + buckets[i] = start + start += width + } + return buckets +} + +// ExponentialBuckets creates 'count' buckets, where the lowest bucket has an +// upper bound of 'start' and each following bucket's upper bound is 'factor' +// times the previous bucket's upper bound. The final +Inf bucket is not counted +// and not included in the returned slice. The returned slice is meant to be +// used for the Buckets field of HistogramOpts. +// +// The function panics if 'count' is 0 or negative, if 'start' is 0 or negative, +// or if 'factor' is less than or equal 1. +func ExponentialBuckets(start, factor float64, count int) []float64 { + if count < 1 { + panic("ExponentialBuckets needs a positive count") + } + if start <= 0 { + panic("ExponentialBuckets needs a positive start value") + } + if factor <= 1 { + panic("ExponentialBuckets needs a factor greater than 1") + } + buckets := make([]float64, count) + for i := range buckets { + buckets[i] = start + start *= factor + } + return buckets +} + +// HistogramOpts bundles the options for creating a Histogram metric. It is +// mandatory to set Name to a non-empty string. All other fields are optional +// and can safely be left at their zero value, although it is strongly +// encouraged to set a Help string. +type HistogramOpts struct { + // Namespace, Subsystem, and Name are components of the fully-qualified + // name of the Histogram (created by joining these components with + // "_"). Only Name is mandatory, the others merely help structuring the + // name. Note that the fully-qualified name of the Histogram must be a + // valid Prometheus metric name. + Namespace string + Subsystem string + Name string + + // Help provides information about this Histogram. + // + // Metrics with the same fully-qualified name must have the same Help + // string. + Help string + + // ConstLabels are used to attach fixed labels to this metric. Metrics + // with the same fully-qualified name must have the same label names in + // their ConstLabels. + // + // ConstLabels are only used rarely. In particular, do not use them to + // attach the same labels to all your metrics. Those use cases are + // better covered by target labels set by the scraping Prometheus + // server, or by one specific metric (e.g. a build_info or a + // machine_role metric). See also + // https://prometheus.io/docs/instrumenting/writing_exporters/#target-labels,-not-static-scraped-labels + ConstLabels Labels + + // Buckets defines the buckets into which observations are counted. Each + // element in the slice is the upper inclusive bound of a bucket. The + // values must be sorted in strictly increasing order. There is no need + // to add a highest bucket with +Inf bound, it will be added + // implicitly. The default value is DefBuckets. + Buckets []float64 +} + +// NewHistogram creates a new Histogram based on the provided HistogramOpts. It +// panics if the buckets in HistogramOpts are not in strictly increasing order. +func NewHistogram(opts HistogramOpts) Histogram { + return newHistogram( + NewDesc( + BuildFQName(opts.Namespace, opts.Subsystem, opts.Name), + opts.Help, + nil, + opts.ConstLabels, + ), + opts, + ) +} + +func newHistogram(desc *Desc, opts HistogramOpts, labelValues ...string) Histogram { + if len(desc.variableLabels) != len(labelValues) { + panic(makeInconsistentCardinalityError(desc.fqName, desc.variableLabels, labelValues)) + } + + for _, n := range desc.variableLabels { + if n == bucketLabel { + panic(errBucketLabelNotAllowed) + } + } + for _, lp := range desc.constLabelPairs { + if lp.GetName() == bucketLabel { + panic(errBucketLabelNotAllowed) + } + } + + if len(opts.Buckets) == 0 { + opts.Buckets = DefBuckets + } + + h := &histogram{ + desc: desc, + upperBounds: opts.Buckets, + labelPairs: makeLabelPairs(desc, labelValues), + counts: [2]*histogramCounts{&histogramCounts{}, &histogramCounts{}}, + } + for i, upperBound := range h.upperBounds { + if i < len(h.upperBounds)-1 { + if upperBound >= h.upperBounds[i+1] { + panic(fmt.Errorf( + "histogram buckets must be in increasing order: %f >= %f", + upperBound, h.upperBounds[i+1], + )) + } + } else { + if math.IsInf(upperBound, +1) { + // The +Inf bucket is implicit. Remove it here. + h.upperBounds = h.upperBounds[:i] + } + } + } + // Finally we know the final length of h.upperBounds and can make buckets + // for both counts: + h.counts[0].buckets = make([]uint64, len(h.upperBounds)) + h.counts[1].buckets = make([]uint64, len(h.upperBounds)) + + h.init(h) // Init self-collection. + return h +} + +type histogramCounts struct { + // sumBits contains the bits of the float64 representing the sum of all + // observations. sumBits and count have to go first in the struct to + // guarantee alignment for atomic operations. + // http://golang.org/pkg/sync/atomic/#pkg-note-BUG + sumBits uint64 + count uint64 + buckets []uint64 +} + +type histogram struct { + // countAndHotIdx enables lock-free writes with use of atomic updates. + // The most significant bit is the hot index [0 or 1] of the count field + // below. Observe calls update the hot one. All remaining bits count the + // number of Observe calls. Observe starts by incrementing this counter, + // and finish by incrementing the count field in the respective + // histogramCounts, as a marker for completion. + // + // Calls of the Write method (which are non-mutating reads from the + // perspective of the histogram) swap the hot–cold under the writeMtx + // lock. A cooldown is awaited (while locked) by comparing the number of + // observations with the initiation count. Once they match, then the + // last observation on the now cool one has completed. All cool fields must + // be merged into the new hot before releasing writeMtx. + // + // Fields with atomic access first! See alignment constraint: + // http://golang.org/pkg/sync/atomic/#pkg-note-BUG + countAndHotIdx uint64 + + selfCollector + desc *Desc + writeMtx sync.Mutex // Only used in the Write method. + + // Two counts, one is "hot" for lock-free observations, the other is + // "cold" for writing out a dto.Metric. It has to be an array of + // pointers to guarantee 64bit alignment of the histogramCounts, see + // http://golang.org/pkg/sync/atomic/#pkg-note-BUG. + counts [2]*histogramCounts + + upperBounds []float64 + labelPairs []*dto.LabelPair +} + +func (h *histogram) Desc() *Desc { + return h.desc +} + +func (h *histogram) Observe(v float64) { + // TODO(beorn7): For small numbers of buckets (<30), a linear search is + // slightly faster than the binary search. If we really care, we could + // switch from one search strategy to the other depending on the number + // of buckets. + // + // Microbenchmarks (BenchmarkHistogramNoLabels): + // 11 buckets: 38.3 ns/op linear - binary 48.7 ns/op + // 100 buckets: 78.1 ns/op linear - binary 54.9 ns/op + // 300 buckets: 154 ns/op linear - binary 61.6 ns/op + i := sort.SearchFloat64s(h.upperBounds, v) + + // We increment h.countAndHotIdx so that the counter in the lower + // 63 bits gets incremented. At the same time, we get the new value + // back, which we can use to find the currently-hot counts. + n := atomic.AddUint64(&h.countAndHotIdx, 1) + hotCounts := h.counts[n>>63] + + if i < len(h.upperBounds) { + atomic.AddUint64(&hotCounts.buckets[i], 1) + } + for { + oldBits := atomic.LoadUint64(&hotCounts.sumBits) + newBits := math.Float64bits(math.Float64frombits(oldBits) + v) + if atomic.CompareAndSwapUint64(&hotCounts.sumBits, oldBits, newBits) { + break + } + } + // Increment count last as we take it as a signal that the observation + // is complete. + atomic.AddUint64(&hotCounts.count, 1) +} + +func (h *histogram) Write(out *dto.Metric) error { + // For simplicity, we protect this whole method by a mutex. It is not in + // the hot path, i.e. Observe is called much more often than Write. The + // complication of making Write lock-free isn't worth it, if possible at + // all. + h.writeMtx.Lock() + defer h.writeMtx.Unlock() + + // Adding 1<<63 switches the hot index (from 0 to 1 or from 1 to 0) + // without touching the count bits. See the struct comments for a full + // description of the algorithm. + n := atomic.AddUint64(&h.countAndHotIdx, 1<<63) + // count is contained unchanged in the lower 63 bits. + count := n & ((1 << 63) - 1) + // The most significant bit tells us which counts is hot. The complement + // is thus the cold one. + hotCounts := h.counts[n>>63] + coldCounts := h.counts[(^n)>>63] + + // Await cooldown. + for count != atomic.LoadUint64(&coldCounts.count) { + runtime.Gosched() // Let observations get work done. + } + + his := &dto.Histogram{ + Bucket: make([]*dto.Bucket, len(h.upperBounds)), + SampleCount: proto.Uint64(count), + SampleSum: proto.Float64(math.Float64frombits(atomic.LoadUint64(&coldCounts.sumBits))), + } + var cumCount uint64 + for i, upperBound := range h.upperBounds { + cumCount += atomic.LoadUint64(&coldCounts.buckets[i]) + his.Bucket[i] = &dto.Bucket{ + CumulativeCount: proto.Uint64(cumCount), + UpperBound: proto.Float64(upperBound), + } + } + + out.Histogram = his + out.Label = h.labelPairs + + // Finally add all the cold counts to the new hot counts and reset the cold counts. + atomic.AddUint64(&hotCounts.count, count) + atomic.StoreUint64(&coldCounts.count, 0) + for { + oldBits := atomic.LoadUint64(&hotCounts.sumBits) + newBits := math.Float64bits(math.Float64frombits(oldBits) + his.GetSampleSum()) + if atomic.CompareAndSwapUint64(&hotCounts.sumBits, oldBits, newBits) { + atomic.StoreUint64(&coldCounts.sumBits, 0) + break + } + } + for i := range h.upperBounds { + atomic.AddUint64(&hotCounts.buckets[i], atomic.LoadUint64(&coldCounts.buckets[i])) + atomic.StoreUint64(&coldCounts.buckets[i], 0) + } + return nil +} + +// HistogramVec is a Collector that bundles a set of Histograms that all share the +// same Desc, but have different values for their variable labels. This is used +// if you want to count the same thing partitioned by various dimensions +// (e.g. HTTP request latencies, partitioned by status code and method). Create +// instances with NewHistogramVec. +type HistogramVec struct { + *metricVec +} + +// NewHistogramVec creates a new HistogramVec based on the provided HistogramOpts and +// partitioned by the given label names. +func NewHistogramVec(opts HistogramOpts, labelNames []string) *HistogramVec { + desc := NewDesc( + BuildFQName(opts.Namespace, opts.Subsystem, opts.Name), + opts.Help, + labelNames, + opts.ConstLabels, + ) + return &HistogramVec{ + metricVec: newMetricVec(desc, func(lvs ...string) Metric { + return newHistogram(desc, opts, lvs...) + }), + } +} + +// GetMetricWithLabelValues returns the Histogram for the given slice of label +// values (same order as the VariableLabels in Desc). If that combination of +// label values is accessed for the first time, a new Histogram is created. +// +// It is possible to call this method without using the returned Histogram to only +// create the new Histogram but leave it at its starting value, a Histogram without +// any observations. +// +// Keeping the Histogram for later use is possible (and should be considered if +// performance is critical), but keep in mind that Reset, DeleteLabelValues and +// Delete can be used to delete the Histogram from the HistogramVec. In that case, the +// Histogram will still exist, but it will not be exported anymore, even if a +// Histogram with the same label values is created later. See also the CounterVec +// example. +// +// An error is returned if the number of label values is not the same as the +// number of VariableLabels in Desc (minus any curried labels). +// +// Note that for more than one label value, this method is prone to mistakes +// caused by an incorrect order of arguments. Consider GetMetricWith(Labels) as +// an alternative to avoid that type of mistake. For higher label numbers, the +// latter has a much more readable (albeit more verbose) syntax, but it comes +// with a performance overhead (for creating and processing the Labels map). +// See also the GaugeVec example. +func (v *HistogramVec) GetMetricWithLabelValues(lvs ...string) (Observer, error) { + metric, err := v.metricVec.getMetricWithLabelValues(lvs...) + if metric != nil { + return metric.(Observer), err + } + return nil, err +} + +// GetMetricWith returns the Histogram for the given Labels map (the label names +// must match those of the VariableLabels in Desc). If that label map is +// accessed for the first time, a new Histogram is created. Implications of +// creating a Histogram without using it and keeping the Histogram for later use +// are the same as for GetMetricWithLabelValues. +// +// An error is returned if the number and names of the Labels are inconsistent +// with those of the VariableLabels in Desc (minus any curried labels). +// +// This method is used for the same purpose as +// GetMetricWithLabelValues(...string). See there for pros and cons of the two +// methods. +func (v *HistogramVec) GetMetricWith(labels Labels) (Observer, error) { + metric, err := v.metricVec.getMetricWith(labels) + if metric != nil { + return metric.(Observer), err + } + return nil, err +} + +// WithLabelValues works as GetMetricWithLabelValues, but panics where +// GetMetricWithLabelValues would have returned an error. Not returning an +// error allows shortcuts like +// myVec.WithLabelValues("404", "GET").Observe(42.21) +func (v *HistogramVec) WithLabelValues(lvs ...string) Observer { + h, err := v.GetMetricWithLabelValues(lvs...) + if err != nil { + panic(err) + } + return h +} + +// With works as GetMetricWith but panics where GetMetricWithLabels would have +// returned an error. Not returning an error allows shortcuts like +// myVec.With(prometheus.Labels{"code": "404", "method": "GET"}).Observe(42.21) +func (v *HistogramVec) With(labels Labels) Observer { + h, err := v.GetMetricWith(labels) + if err != nil { + panic(err) + } + return h +} + +// CurryWith returns a vector curried with the provided labels, i.e. the +// returned vector has those labels pre-set for all labeled operations performed +// on it. The cardinality of the curried vector is reduced accordingly. The +// order of the remaining labels stays the same (just with the curried labels +// taken out of the sequence – which is relevant for the +// (GetMetric)WithLabelValues methods). It is possible to curry a curried +// vector, but only with labels not yet used for currying before. +// +// The metrics contained in the HistogramVec are shared between the curried and +// uncurried vectors. They are just accessed differently. Curried and uncurried +// vectors behave identically in terms of collection. Only one must be +// registered with a given registry (usually the uncurried version). The Reset +// method deletes all metrics, even if called on a curried vector. +func (v *HistogramVec) CurryWith(labels Labels) (ObserverVec, error) { + vec, err := v.curryWith(labels) + if vec != nil { + return &HistogramVec{vec}, err + } + return nil, err +} + +// MustCurryWith works as CurryWith but panics where CurryWith would have +// returned an error. +func (v *HistogramVec) MustCurryWith(labels Labels) ObserverVec { + vec, err := v.CurryWith(labels) + if err != nil { + panic(err) + } + return vec +} + +type constHistogram struct { + desc *Desc + count uint64 + sum float64 + buckets map[float64]uint64 + labelPairs []*dto.LabelPair +} + +func (h *constHistogram) Desc() *Desc { + return h.desc +} + +func (h *constHistogram) Write(out *dto.Metric) error { + his := &dto.Histogram{} + buckets := make([]*dto.Bucket, 0, len(h.buckets)) + + his.SampleCount = proto.Uint64(h.count) + his.SampleSum = proto.Float64(h.sum) + + for upperBound, count := range h.buckets { + buckets = append(buckets, &dto.Bucket{ + CumulativeCount: proto.Uint64(count), + UpperBound: proto.Float64(upperBound), + }) + } + + if len(buckets) > 0 { + sort.Sort(buckSort(buckets)) + } + his.Bucket = buckets + + out.Histogram = his + out.Label = h.labelPairs + + return nil +} + +// NewConstHistogram returns a metric representing a Prometheus histogram with +// fixed values for the count, sum, and bucket counts. As those parameters +// cannot be changed, the returned value does not implement the Histogram +// interface (but only the Metric interface). Users of this package will not +// have much use for it in regular operations. However, when implementing custom +// Collectors, it is useful as a throw-away metric that is generated on the fly +// to send it to Prometheus in the Collect method. +// +// buckets is a map of upper bounds to cumulative counts, excluding the +Inf +// bucket. +// +// NewConstHistogram returns an error if the length of labelValues is not +// consistent with the variable labels in Desc or if Desc is invalid. +func NewConstHistogram( + desc *Desc, + count uint64, + sum float64, + buckets map[float64]uint64, + labelValues ...string, +) (Metric, error) { + if desc.err != nil { + return nil, desc.err + } + if err := validateLabelValues(labelValues, len(desc.variableLabels)); err != nil { + return nil, err + } + return &constHistogram{ + desc: desc, + count: count, + sum: sum, + buckets: buckets, + labelPairs: makeLabelPairs(desc, labelValues), + }, nil +} + +// MustNewConstHistogram is a version of NewConstHistogram that panics where +// NewConstMetric would have returned an error. +func MustNewConstHistogram( + desc *Desc, + count uint64, + sum float64, + buckets map[float64]uint64, + labelValues ...string, +) Metric { + m, err := NewConstHistogram(desc, count, sum, buckets, labelValues...) + if err != nil { + panic(err) + } + return m +} + +type buckSort []*dto.Bucket + +func (s buckSort) Len() int { + return len(s) +} + +func (s buckSort) Swap(i, j int) { + s[i], s[j] = s[j], s[i] +} + +func (s buckSort) Less(i, j int) bool { + return s[i].GetUpperBound() < s[j].GetUpperBound() +} diff --git a/vendor/github.com/prometheus/client_golang/prometheus/internal/metric.go b/vendor/github.com/prometheus/client_golang/prometheus/internal/metric.go new file mode 100644 index 000000000..351c26e1a --- /dev/null +++ b/vendor/github.com/prometheus/client_golang/prometheus/internal/metric.go @@ -0,0 +1,85 @@ +// Copyright 2018 The Prometheus Authors +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package internal + +import ( + "sort" + + dto "github.com/prometheus/client_model/go" +) + +// metricSorter is a sortable slice of *dto.Metric. +type metricSorter []*dto.Metric + +func (s metricSorter) Len() int { + return len(s) +} + +func (s metricSorter) Swap(i, j int) { + s[i], s[j] = s[j], s[i] +} + +func (s metricSorter) Less(i, j int) bool { + if len(s[i].Label) != len(s[j].Label) { + // This should not happen. The metrics are + // inconsistent. However, we have to deal with the fact, as + // people might use custom collectors or metric family injection + // to create inconsistent metrics. So let's simply compare the + // number of labels in this case. That will still yield + // reproducible sorting. + return len(s[i].Label) < len(s[j].Label) + } + for n, lp := range s[i].Label { + vi := lp.GetValue() + vj := s[j].Label[n].GetValue() + if vi != vj { + return vi < vj + } + } + + // We should never arrive here. Multiple metrics with the same + // label set in the same scrape will lead to undefined ingestion + // behavior. However, as above, we have to provide stable sorting + // here, even for inconsistent metrics. So sort equal metrics + // by their timestamp, with missing timestamps (implying "now") + // coming last. + if s[i].TimestampMs == nil { + return false + } + if s[j].TimestampMs == nil { + return true + } + return s[i].GetTimestampMs() < s[j].GetTimestampMs() +} + +// NormalizeMetricFamilies returns a MetricFamily slice with empty +// MetricFamilies pruned and the remaining MetricFamilies sorted by name within +// the slice, with the contained Metrics sorted within each MetricFamily. +func NormalizeMetricFamilies(metricFamiliesByName map[string]*dto.MetricFamily) []*dto.MetricFamily { + for _, mf := range metricFamiliesByName { + sort.Sort(metricSorter(mf.Metric)) + } + names := make([]string, 0, len(metricFamiliesByName)) + for name, mf := range metricFamiliesByName { + if len(mf.Metric) > 0 { + names = append(names, name) + } + } + sort.Strings(names) + result := make([]*dto.MetricFamily, 0, len(names)) + for _, name := range names { + result = append(result, metricFamiliesByName[name]) + } + return result +} diff --git a/vendor/github.com/prometheus/client_golang/prometheus/labels.go b/vendor/github.com/prometheus/client_golang/prometheus/labels.go new file mode 100644 index 000000000..2744443ac --- /dev/null +++ b/vendor/github.com/prometheus/client_golang/prometheus/labels.go @@ -0,0 +1,87 @@ +// Copyright 2018 The Prometheus Authors +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package prometheus + +import ( + "errors" + "fmt" + "strings" + "unicode/utf8" + + "github.com/prometheus/common/model" +) + +// Labels represents a collection of label name -> value mappings. This type is +// commonly used with the With(Labels) and GetMetricWith(Labels) methods of +// metric vector Collectors, e.g.: +// myVec.With(Labels{"code": "404", "method": "GET"}).Add(42) +// +// The other use-case is the specification of constant label pairs in Opts or to +// create a Desc. +type Labels map[string]string + +// reservedLabelPrefix is a prefix which is not legal in user-supplied +// label names. +const reservedLabelPrefix = "__" + +var errInconsistentCardinality = errors.New("inconsistent label cardinality") + +func makeInconsistentCardinalityError(fqName string, labels, labelValues []string) error { + return fmt.Errorf( + "%s: %q has %d variable labels named %q but %d values %q were provided", + errInconsistentCardinality, fqName, + len(labels), labels, + len(labelValues), labelValues, + ) +} + +func validateValuesInLabels(labels Labels, expectedNumberOfValues int) error { + if len(labels) != expectedNumberOfValues { + return fmt.Errorf( + "%s: expected %d label values but got %d in %#v", + errInconsistentCardinality, expectedNumberOfValues, + len(labels), labels, + ) + } + + for name, val := range labels { + if !utf8.ValidString(val) { + return fmt.Errorf("label %s: value %q is not valid UTF-8", name, val) + } + } + + return nil +} + +func validateLabelValues(vals []string, expectedNumberOfValues int) error { + if len(vals) != expectedNumberOfValues { + return fmt.Errorf( + "%s: expected %d label values but got %d in %#v", + errInconsistentCardinality, expectedNumberOfValues, + len(vals), vals, + ) + } + + for _, val := range vals { + if !utf8.ValidString(val) { + return fmt.Errorf("label value %q is not valid UTF-8", val) + } + } + + return nil +} + +func checkLabelName(l string) bool { + return model.LabelName(l).IsValid() && !strings.HasPrefix(l, reservedLabelPrefix) +} diff --git a/vendor/github.com/prometheus/client_golang/prometheus/metric.go b/vendor/github.com/prometheus/client_golang/prometheus/metric.go new file mode 100644 index 000000000..55e6d86d5 --- /dev/null +++ b/vendor/github.com/prometheus/client_golang/prometheus/metric.go @@ -0,0 +1,174 @@ +// 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 prometheus + +import ( + "strings" + "time" + + "github.com/golang/protobuf/proto" + + 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. +type Metric interface { + // Desc returns the descriptor for the Metric. This method idempotently + // returns the same descriptor throughout the lifetime of the + // Metric. The returned descriptor is immutable by contract. A Metric + // unable to describe itself must return an invalid descriptor (created + // with NewInvalidDesc). + Desc() *Desc + // 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. + // + // 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. Callers of Write should + // still make sure of sorting if they depend on it. + Write(*dto.Metric) error + // TODO(beorn7): The original rationale of passing in a pre-allocated + // dto.Metric protobuf to save allocations has disappeared. The + // signature of this method should be changed to "Write() (*dto.Metric, + // error)". +} + +// Opts bundles the options for creating most Metric types. Each metric +// implementation XXX has its own XXXOpts type, but in most cases, it is just be +// an alias of this type (which might change when the requirement arises.) +// +// It is mandatory to set Name to a non-empty string. All other fields are +// optional and can safely be left at their zero value, although it is strongly +// encouraged to set a Help string. +type Opts struct { + // Namespace, Subsystem, and Name are components of the fully-qualified + // name of the Metric (created by joining these components with + // "_"). Only Name is mandatory, the others merely help structuring the + // name. Note that the fully-qualified name of the metric must be a + // valid Prometheus metric name. + Namespace string + Subsystem string + Name string + + // Help provides information about this metric. + // + // Metrics with the same fully-qualified name must have the same Help + // string. + Help string + + // ConstLabels are used to attach fixed labels to this metric. Metrics + // with the same fully-qualified name must have the same label names in + // their ConstLabels. + // + // ConstLabels are only used rarely. In particular, do not use them to + // attach the same labels to all your metrics. Those use cases are + // better covered by target labels set by the scraping Prometheus + // server, or by one specific metric (e.g. a build_info or a + // machine_role metric). See also + // https://prometheus.io/docs/instrumenting/writing_exporters/#target-labels,-not-static-scraped-labels + ConstLabels Labels +} + +// BuildFQName joins the given three name components by "_". Empty name +// components are ignored. If the name parameter itself is empty, an empty +// string is returned, no matter what. Metric implementations included in this +// library use this function internally to generate the fully-qualified metric +// name from the name component in their Opts. Users of the library will only +// need this function if they implement their own Metric or instantiate a Desc +// (with NewDesc) directly. +func BuildFQName(namespace, subsystem, name string) string { + if name == "" { + return "" + } + switch { + case namespace != "" && subsystem != "": + return strings.Join([]string{namespace, subsystem, name}, "_") + case namespace != "": + return strings.Join([]string{namespace, name}, "_") + case subsystem != "": + return strings.Join([]string{subsystem, name}, "_") + } + return name +} + +// labelPairSorter implements sort.Interface. It is used to sort a slice of +// dto.LabelPair pointers. +type labelPairSorter []*dto.LabelPair + +func (s labelPairSorter) Len() int { + return len(s) +} + +func (s labelPairSorter) Swap(i, j int) { + s[i], s[j] = s[j], s[i] +} + +func (s labelPairSorter) Less(i, j int) bool { + return s[i].GetName() < s[j].GetName() +} + +type invalidMetric struct { + desc *Desc + err error +} + +// NewInvalidMetric returns a metric whose Write method always returns the +// provided error. It is useful if a Collector finds itself unable to collect +// a metric and wishes to report an error to the registry. +func NewInvalidMetric(desc *Desc, err error) Metric { + return &invalidMetric{desc, err} +} + +func (m *invalidMetric) Desc() *Desc { return m.desc } + +func (m *invalidMetric) Write(*dto.Metric) error { return m.err } + +type timestampedMetric struct { + Metric + t time.Time +} + +func (m timestampedMetric) Write(pb *dto.Metric) error { + e := m.Metric.Write(pb) + pb.TimestampMs = proto.Int64(m.t.Unix()*1000 + int64(m.t.Nanosecond()/1000000)) + return e +} + +// NewMetricWithTimestamp returns a new Metric wrapping the provided Metric in a +// way that it has an explicit timestamp set to the provided Time. This is only +// useful in rare cases as the timestamp of a Prometheus metric should usually +// be set by the Prometheus server during scraping. Exceptions include mirroring +// metrics with given timestamps from other metric +// sources. +// +// NewMetricWithTimestamp works best with MustNewConstMetric, +// MustNewConstHistogram, and MustNewConstSummary, see example. +// +// Currently, the exposition formats used by Prometheus are limited to +// millisecond resolution. Thus, the provided time will be rounded down to the +// next full millisecond value. +func NewMetricWithTimestamp(t time.Time, m Metric) Metric { + return timestampedMetric{Metric: m, t: t} +} diff --git a/vendor/github.com/prometheus/client_golang/prometheus/observer.go b/vendor/github.com/prometheus/client_golang/prometheus/observer.go new file mode 100644 index 000000000..5806cd09e --- /dev/null +++ b/vendor/github.com/prometheus/client_golang/prometheus/observer.go @@ -0,0 +1,52 @@ +// Copyright 2017 The Prometheus Authors +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package prometheus + +// Observer is the interface that wraps the Observe method, which is used by +// Histogram and Summary to add observations. +type Observer interface { + Observe(float64) +} + +// The ObserverFunc type is an adapter to allow the use of ordinary +// functions as Observers. If f is a function with the appropriate +// signature, ObserverFunc(f) is an Observer that calls f. +// +// This adapter is usually used in connection with the Timer type, and there are +// two general use cases: +// +// The most common one is to use a Gauge as the Observer for a Timer. +// See the "Gauge" Timer example. +// +// The more advanced use case is to create a function that dynamically decides +// which Observer to use for observing the duration. See the "Complex" Timer +// example. +type ObserverFunc func(float64) + +// Observe calls f(value). It implements Observer. +func (f ObserverFunc) Observe(value float64) { + f(value) +} + +// ObserverVec is an interface implemented by `HistogramVec` and `SummaryVec`. +type ObserverVec interface { + GetMetricWith(Labels) (Observer, error) + GetMetricWithLabelValues(lvs ...string) (Observer, error) + With(Labels) Observer + WithLabelValues(...string) Observer + CurryWith(Labels) (ObserverVec, error) + MustCurryWith(Labels) ObserverVec + + Collector +} diff --git a/vendor/github.com/prometheus/client_golang/prometheus/process_collector.go b/vendor/github.com/prometheus/client_golang/prometheus/process_collector.go new file mode 100644 index 000000000..9b8097942 --- /dev/null +++ b/vendor/github.com/prometheus/client_golang/prometheus/process_collector.go @@ -0,0 +1,151 @@ +// 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. + +package prometheus + +import ( + "errors" + "os" +) + +type processCollector struct { + collectFn func(chan<- Metric) + pidFn func() (int, error) + reportErrors bool + cpuTotal *Desc + openFDs, maxFDs *Desc + vsize, maxVsize *Desc + rss *Desc + startTime *Desc +} + +// ProcessCollectorOpts defines the behavior of a process metrics collector +// created with NewProcessCollector. +type ProcessCollectorOpts struct { + // PidFn returns the PID of the process the collector collects metrics + // for. It is called upon each collection. By default, the PID of the + // current process is used, as determined on construction time by + // calling os.Getpid(). + PidFn func() (int, error) + // If non-empty, each of the collected metrics is prefixed by the + // provided string and an underscore ("_"). + Namespace string + // If true, any error encountered during collection is reported as an + // invalid metric (see NewInvalidMetric). Otherwise, errors are ignored + // and the collected metrics will be incomplete. (Possibly, no metrics + // will be collected at all.) While that's usually not desired, it is + // appropriate for the common "mix-in" of process metrics, where process + // metrics are nice to have, but failing to collect them should not + // disrupt the collection of the remaining metrics. + ReportErrors bool +} + +// NewProcessCollector returns a collector which exports the current state of +// process metrics including CPU, memory and file descriptor usage as well as +// the process start time. The detailed behavior is defined by the provided +// ProcessCollectorOpts. The zero value of ProcessCollectorOpts creates a +// collector for the current process with an empty namespace string and no error +// reporting. +// +// The collector only works on operating systems with a Linux-style proc +// filesystem and on Microsoft Windows. On other operating systems, it will not +// collect any metrics. +func NewProcessCollector(opts ProcessCollectorOpts) Collector { + ns := "" + if len(opts.Namespace) > 0 { + ns = opts.Namespace + "_" + } + + c := &processCollector{ + reportErrors: opts.ReportErrors, + cpuTotal: NewDesc( + ns+"process_cpu_seconds_total", + "Total user and system CPU time spent in seconds.", + nil, nil, + ), + openFDs: NewDesc( + ns+"process_open_fds", + "Number of open file descriptors.", + nil, nil, + ), + maxFDs: NewDesc( + ns+"process_max_fds", + "Maximum number of open file descriptors.", + nil, nil, + ), + vsize: NewDesc( + ns+"process_virtual_memory_bytes", + "Virtual memory size in bytes.", + nil, nil, + ), + maxVsize: NewDesc( + ns+"process_virtual_memory_max_bytes", + "Maximum amount of virtual memory available in bytes.", + nil, nil, + ), + rss: NewDesc( + ns+"process_resident_memory_bytes", + "Resident memory size in bytes.", + nil, nil, + ), + startTime: NewDesc( + ns+"process_start_time_seconds", + "Start time of the process since unix epoch in seconds.", + nil, nil, + ), + } + + if opts.PidFn == nil { + pid := os.Getpid() + c.pidFn = func() (int, error) { return pid, nil } + } else { + c.pidFn = opts.PidFn + } + + // Set up process metric collection if supported by the runtime. + if canCollectProcess() { + c.collectFn = c.processCollect + } else { + c.collectFn = func(ch chan<- Metric) { + c.reportError(ch, nil, errors.New("process metrics not supported on this platform")) + } + } + + return c +} + +// Describe returns all descriptions of the collector. +func (c *processCollector) Describe(ch chan<- *Desc) { + ch <- c.cpuTotal + ch <- c.openFDs + ch <- c.maxFDs + ch <- c.vsize + ch <- c.maxVsize + ch <- c.rss + ch <- c.startTime +} + +// Collect returns the current state of all metrics of the collector. +func (c *processCollector) Collect(ch chan<- Metric) { + c.collectFn(ch) +} + +func (c *processCollector) reportError(ch chan<- Metric, desc *Desc, err error) { + if !c.reportErrors { + return + } + if desc == nil { + desc = NewInvalidDesc(err) + } + ch <- NewInvalidMetric(desc, err) +} diff --git a/vendor/github.com/prometheus/client_golang/prometheus/process_collector_other.go b/vendor/github.com/prometheus/client_golang/prometheus/process_collector_other.go new file mode 100644 index 000000000..3117461cd --- /dev/null +++ b/vendor/github.com/prometheus/client_golang/prometheus/process_collector_other.go @@ -0,0 +1,65 @@ +// Copyright 2019 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. + +// +build !windows + +package prometheus + +import ( + "github.com/prometheus/procfs" +) + +func canCollectProcess() bool { + _, err := procfs.NewDefaultFS() + return err == nil +} + +func (c *processCollector) processCollect(ch chan<- Metric) { + pid, err := c.pidFn() + if err != nil { + c.reportError(ch, nil, err) + return + } + + p, err := procfs.NewProc(pid) + if err != nil { + c.reportError(ch, nil, err) + return + } + + if stat, err := p.Stat(); err == nil { + ch <- MustNewConstMetric(c.cpuTotal, CounterValue, stat.CPUTime()) + ch <- MustNewConstMetric(c.vsize, GaugeValue, float64(stat.VirtualMemory())) + ch <- MustNewConstMetric(c.rss, GaugeValue, float64(stat.ResidentMemory())) + if startTime, err := stat.StartTime(); err == nil { + ch <- MustNewConstMetric(c.startTime, GaugeValue, startTime) + } else { + c.reportError(ch, c.startTime, err) + } + } else { + c.reportError(ch, nil, err) + } + + if fds, err := p.FileDescriptorsLen(); err == nil { + ch <- MustNewConstMetric(c.openFDs, GaugeValue, float64(fds)) + } else { + c.reportError(ch, c.openFDs, err) + } + + if limits, err := p.Limits(); err == nil { + ch <- MustNewConstMetric(c.maxFDs, GaugeValue, float64(limits.OpenFiles)) + ch <- MustNewConstMetric(c.maxVsize, GaugeValue, float64(limits.AddressSpace)) + } else { + c.reportError(ch, nil, err) + } +} diff --git a/vendor/github.com/prometheus/client_golang/prometheus/process_collector_windows.go b/vendor/github.com/prometheus/client_golang/prometheus/process_collector_windows.go new file mode 100644 index 000000000..e0b935d1f --- /dev/null +++ b/vendor/github.com/prometheus/client_golang/prometheus/process_collector_windows.go @@ -0,0 +1,112 @@ +// Copyright 2019 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 ( + "syscall" + "unsafe" + + "golang.org/x/sys/windows" +) + +func canCollectProcess() bool { + return true +} + +var ( + modpsapi = syscall.NewLazyDLL("psapi.dll") + modkernel32 = syscall.NewLazyDLL("kernel32.dll") + + procGetProcessMemoryInfo = modpsapi.NewProc("GetProcessMemoryInfo") + procGetProcessHandleCount = modkernel32.NewProc("GetProcessHandleCount") +) + +type processMemoryCounters struct { + // https://docs.microsoft.com/en-us/windows/desktop/api/psapi/ns-psapi-_process_memory_counters_ex + _ uint32 + PageFaultCount uint32 + PeakWorkingSetSize uint64 + WorkingSetSize uint64 + QuotaPeakPagedPoolUsage uint64 + QuotaPagedPoolUsage uint64 + QuotaPeakNonPagedPoolUsage uint64 + QuotaNonPagedPoolUsage uint64 + PagefileUsage uint64 + PeakPagefileUsage uint64 + PrivateUsage uint64 +} + +func getProcessMemoryInfo(handle windows.Handle) (processMemoryCounters, error) { + mem := processMemoryCounters{} + r1, _, err := procGetProcessMemoryInfo.Call( + uintptr(handle), + uintptr(unsafe.Pointer(&mem)), + uintptr(unsafe.Sizeof(mem)), + ) + if r1 != 1 { + return mem, err + } else { + return mem, nil + } +} + +func getProcessHandleCount(handle windows.Handle) (uint32, error) { + var count uint32 + r1, _, err := procGetProcessHandleCount.Call( + uintptr(handle), + uintptr(unsafe.Pointer(&count)), + ) + if r1 != 1 { + return 0, err + } else { + return count, nil + } +} + +func (c *processCollector) processCollect(ch chan<- Metric) { + h, err := windows.GetCurrentProcess() + if err != nil { + c.reportError(ch, nil, err) + return + } + + var startTime, exitTime, kernelTime, userTime windows.Filetime + err = windows.GetProcessTimes(h, &startTime, &exitTime, &kernelTime, &userTime) + if err != nil { + c.reportError(ch, nil, err) + return + } + ch <- MustNewConstMetric(c.startTime, GaugeValue, float64(startTime.Nanoseconds()/1e9)) + ch <- MustNewConstMetric(c.cpuTotal, CounterValue, fileTimeToSeconds(kernelTime)+fileTimeToSeconds(userTime)) + + mem, err := getProcessMemoryInfo(h) + if err != nil { + c.reportError(ch, nil, err) + return + } + ch <- MustNewConstMetric(c.vsize, GaugeValue, float64(mem.PrivateUsage)) + ch <- MustNewConstMetric(c.rss, GaugeValue, float64(mem.WorkingSetSize)) + + handles, err := getProcessHandleCount(h) + if err != nil { + c.reportError(ch, nil, err) + return + } + ch <- MustNewConstMetric(c.openFDs, GaugeValue, float64(handles)) + ch <- MustNewConstMetric(c.maxFDs, GaugeValue, float64(16*1024*1024)) // Windows has a hard-coded max limit, not per-process. +} + +func fileTimeToSeconds(ft windows.Filetime) float64 { + return float64(uint64(ft.HighDateTime)<<32+uint64(ft.LowDateTime)) / 1e7 +} diff --git a/vendor/github.com/prometheus/client_golang/prometheus/promhttp/delegator.go b/vendor/github.com/prometheus/client_golang/prometheus/promhttp/delegator.go new file mode 100644 index 000000000..fa535684f --- /dev/null +++ b/vendor/github.com/prometheus/client_golang/prometheus/promhttp/delegator.go @@ -0,0 +1,357 @@ +// Copyright 2017 The Prometheus Authors +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package promhttp + +import ( + "bufio" + "io" + "net" + "net/http" +) + +const ( + closeNotifier = 1 << iota + flusher + hijacker + readerFrom + pusher +) + +type delegator interface { + http.ResponseWriter + + Status() int + Written() int64 +} + +type responseWriterDelegator struct { + http.ResponseWriter + + status int + written int64 + wroteHeader bool + observeWriteHeader func(int) +} + +func (r *responseWriterDelegator) Status() int { + return r.status +} + +func (r *responseWriterDelegator) Written() int64 { + return r.written +} + +func (r *responseWriterDelegator) WriteHeader(code int) { + r.status = code + r.wroteHeader = true + r.ResponseWriter.WriteHeader(code) + if r.observeWriteHeader != nil { + r.observeWriteHeader(code) + } +} + +func (r *responseWriterDelegator) Write(b []byte) (int, error) { + if !r.wroteHeader { + r.WriteHeader(http.StatusOK) + } + n, err := r.ResponseWriter.Write(b) + r.written += int64(n) + return n, err +} + +type closeNotifierDelegator struct{ *responseWriterDelegator } +type flusherDelegator struct{ *responseWriterDelegator } +type hijackerDelegator struct{ *responseWriterDelegator } +type readerFromDelegator struct{ *responseWriterDelegator } +type pusherDelegator struct{ *responseWriterDelegator } + +func (d closeNotifierDelegator) CloseNotify() <-chan bool { + //lint:ignore SA1019 http.CloseNotifier is deprecated but we don't want to + //remove support from client_golang yet. + return d.ResponseWriter.(http.CloseNotifier).CloseNotify() +} +func (d flusherDelegator) Flush() { + d.ResponseWriter.(http.Flusher).Flush() +} +func (d hijackerDelegator) Hijack() (net.Conn, *bufio.ReadWriter, error) { + return d.ResponseWriter.(http.Hijacker).Hijack() +} +func (d readerFromDelegator) ReadFrom(re io.Reader) (int64, error) { + if !d.wroteHeader { + d.WriteHeader(http.StatusOK) + } + n, err := d.ResponseWriter.(io.ReaderFrom).ReadFrom(re) + d.written += n + return n, err +} +func (d pusherDelegator) Push(target string, opts *http.PushOptions) error { + return d.ResponseWriter.(http.Pusher).Push(target, opts) +} + +var pickDelegator = make([]func(*responseWriterDelegator) delegator, 32) + +func init() { + // TODO(beorn7): Code generation would help here. + pickDelegator[0] = func(d *responseWriterDelegator) delegator { // 0 + return d + } + pickDelegator[closeNotifier] = func(d *responseWriterDelegator) delegator { // 1 + return closeNotifierDelegator{d} + } + pickDelegator[flusher] = func(d *responseWriterDelegator) delegator { // 2 + return flusherDelegator{d} + } + pickDelegator[flusher+closeNotifier] = func(d *responseWriterDelegator) delegator { // 3 + return struct { + *responseWriterDelegator + http.Flusher + http.CloseNotifier + }{d, flusherDelegator{d}, closeNotifierDelegator{d}} + } + pickDelegator[hijacker] = func(d *responseWriterDelegator) delegator { // 4 + return hijackerDelegator{d} + } + pickDelegator[hijacker+closeNotifier] = func(d *responseWriterDelegator) delegator { // 5 + return struct { + *responseWriterDelegator + http.Hijacker + http.CloseNotifier + }{d, hijackerDelegator{d}, closeNotifierDelegator{d}} + } + pickDelegator[hijacker+flusher] = func(d *responseWriterDelegator) delegator { // 6 + return struct { + *responseWriterDelegator + http.Hijacker + http.Flusher + }{d, hijackerDelegator{d}, flusherDelegator{d}} + } + pickDelegator[hijacker+flusher+closeNotifier] = func(d *responseWriterDelegator) delegator { // 7 + return struct { + *responseWriterDelegator + http.Hijacker + http.Flusher + http.CloseNotifier + }{d, hijackerDelegator{d}, flusherDelegator{d}, closeNotifierDelegator{d}} + } + pickDelegator[readerFrom] = func(d *responseWriterDelegator) delegator { // 8 + return readerFromDelegator{d} + } + pickDelegator[readerFrom+closeNotifier] = func(d *responseWriterDelegator) delegator { // 9 + return struct { + *responseWriterDelegator + io.ReaderFrom + http.CloseNotifier + }{d, readerFromDelegator{d}, closeNotifierDelegator{d}} + } + pickDelegator[readerFrom+flusher] = func(d *responseWriterDelegator) delegator { // 10 + return struct { + *responseWriterDelegator + io.ReaderFrom + http.Flusher + }{d, readerFromDelegator{d}, flusherDelegator{d}} + } + pickDelegator[readerFrom+flusher+closeNotifier] = func(d *responseWriterDelegator) delegator { // 11 + return struct { + *responseWriterDelegator + io.ReaderFrom + http.Flusher + http.CloseNotifier + }{d, readerFromDelegator{d}, flusherDelegator{d}, closeNotifierDelegator{d}} + } + pickDelegator[readerFrom+hijacker] = func(d *responseWriterDelegator) delegator { // 12 + return struct { + *responseWriterDelegator + io.ReaderFrom + http.Hijacker + }{d, readerFromDelegator{d}, hijackerDelegator{d}} + } + pickDelegator[readerFrom+hijacker+closeNotifier] = func(d *responseWriterDelegator) delegator { // 13 + return struct { + *responseWriterDelegator + io.ReaderFrom + http.Hijacker + http.CloseNotifier + }{d, readerFromDelegator{d}, hijackerDelegator{d}, closeNotifierDelegator{d}} + } + pickDelegator[readerFrom+hijacker+flusher] = func(d *responseWriterDelegator) delegator { // 14 + return struct { + *responseWriterDelegator + io.ReaderFrom + http.Hijacker + http.Flusher + }{d, readerFromDelegator{d}, hijackerDelegator{d}, flusherDelegator{d}} + } + pickDelegator[readerFrom+hijacker+flusher+closeNotifier] = func(d *responseWriterDelegator) delegator { // 15 + return struct { + *responseWriterDelegator + io.ReaderFrom + http.Hijacker + http.Flusher + http.CloseNotifier + }{d, readerFromDelegator{d}, hijackerDelegator{d}, flusherDelegator{d}, closeNotifierDelegator{d}} + } + pickDelegator[pusher] = func(d *responseWriterDelegator) delegator { // 16 + return pusherDelegator{d} + } + pickDelegator[pusher+closeNotifier] = func(d *responseWriterDelegator) delegator { // 17 + return struct { + *responseWriterDelegator + http.Pusher + http.CloseNotifier + }{d, pusherDelegator{d}, closeNotifierDelegator{d}} + } + pickDelegator[pusher+flusher] = func(d *responseWriterDelegator) delegator { // 18 + return struct { + *responseWriterDelegator + http.Pusher + http.Flusher + }{d, pusherDelegator{d}, flusherDelegator{d}} + } + pickDelegator[pusher+flusher+closeNotifier] = func(d *responseWriterDelegator) delegator { // 19 + return struct { + *responseWriterDelegator + http.Pusher + http.Flusher + http.CloseNotifier + }{d, pusherDelegator{d}, flusherDelegator{d}, closeNotifierDelegator{d}} + } + pickDelegator[pusher+hijacker] = func(d *responseWriterDelegator) delegator { // 20 + return struct { + *responseWriterDelegator + http.Pusher + http.Hijacker + }{d, pusherDelegator{d}, hijackerDelegator{d}} + } + pickDelegator[pusher+hijacker+closeNotifier] = func(d *responseWriterDelegator) delegator { // 21 + return struct { + *responseWriterDelegator + http.Pusher + http.Hijacker + http.CloseNotifier + }{d, pusherDelegator{d}, hijackerDelegator{d}, closeNotifierDelegator{d}} + } + pickDelegator[pusher+hijacker+flusher] = func(d *responseWriterDelegator) delegator { // 22 + return struct { + *responseWriterDelegator + http.Pusher + http.Hijacker + http.Flusher + }{d, pusherDelegator{d}, hijackerDelegator{d}, flusherDelegator{d}} + } + pickDelegator[pusher+hijacker+flusher+closeNotifier] = func(d *responseWriterDelegator) delegator { //23 + return struct { + *responseWriterDelegator + http.Pusher + http.Hijacker + http.Flusher + http.CloseNotifier + }{d, pusherDelegator{d}, hijackerDelegator{d}, flusherDelegator{d}, closeNotifierDelegator{d}} + } + pickDelegator[pusher+readerFrom] = func(d *responseWriterDelegator) delegator { // 24 + return struct { + *responseWriterDelegator + http.Pusher + io.ReaderFrom + }{d, pusherDelegator{d}, readerFromDelegator{d}} + } + pickDelegator[pusher+readerFrom+closeNotifier] = func(d *responseWriterDelegator) delegator { // 25 + return struct { + *responseWriterDelegator + http.Pusher + io.ReaderFrom + http.CloseNotifier + }{d, pusherDelegator{d}, readerFromDelegator{d}, closeNotifierDelegator{d}} + } + pickDelegator[pusher+readerFrom+flusher] = func(d *responseWriterDelegator) delegator { // 26 + return struct { + *responseWriterDelegator + http.Pusher + io.ReaderFrom + http.Flusher + }{d, pusherDelegator{d}, readerFromDelegator{d}, flusherDelegator{d}} + } + pickDelegator[pusher+readerFrom+flusher+closeNotifier] = func(d *responseWriterDelegator) delegator { // 27 + return struct { + *responseWriterDelegator + http.Pusher + io.ReaderFrom + http.Flusher + http.CloseNotifier + }{d, pusherDelegator{d}, readerFromDelegator{d}, flusherDelegator{d}, closeNotifierDelegator{d}} + } + pickDelegator[pusher+readerFrom+hijacker] = func(d *responseWriterDelegator) delegator { // 28 + return struct { + *responseWriterDelegator + http.Pusher + io.ReaderFrom + http.Hijacker + }{d, pusherDelegator{d}, readerFromDelegator{d}, hijackerDelegator{d}} + } + pickDelegator[pusher+readerFrom+hijacker+closeNotifier] = func(d *responseWriterDelegator) delegator { // 29 + return struct { + *responseWriterDelegator + http.Pusher + io.ReaderFrom + http.Hijacker + http.CloseNotifier + }{d, pusherDelegator{d}, readerFromDelegator{d}, hijackerDelegator{d}, closeNotifierDelegator{d}} + } + pickDelegator[pusher+readerFrom+hijacker+flusher] = func(d *responseWriterDelegator) delegator { // 30 + return struct { + *responseWriterDelegator + http.Pusher + io.ReaderFrom + http.Hijacker + http.Flusher + }{d, pusherDelegator{d}, readerFromDelegator{d}, hijackerDelegator{d}, flusherDelegator{d}} + } + pickDelegator[pusher+readerFrom+hijacker+flusher+closeNotifier] = func(d *responseWriterDelegator) delegator { // 31 + return struct { + *responseWriterDelegator + http.Pusher + io.ReaderFrom + http.Hijacker + http.Flusher + http.CloseNotifier + }{d, pusherDelegator{d}, readerFromDelegator{d}, hijackerDelegator{d}, flusherDelegator{d}, closeNotifierDelegator{d}} + } +} + +func newDelegator(w http.ResponseWriter, observeWriteHeaderFunc func(int)) delegator { + d := &responseWriterDelegator{ + ResponseWriter: w, + observeWriteHeader: observeWriteHeaderFunc, + } + + id := 0 + //lint:ignore SA1019 http.CloseNotifier is deprecated but we don't want to + //remove support from client_golang yet. + if _, ok := w.(http.CloseNotifier); ok { + id += closeNotifier + } + if _, ok := w.(http.Flusher); ok { + id += flusher + } + if _, ok := w.(http.Hijacker); ok { + id += hijacker + } + if _, ok := w.(io.ReaderFrom); ok { + id += readerFrom + } + if _, ok := w.(http.Pusher); ok { + id += pusher + } + + return pickDelegator[id](d) +} diff --git a/vendor/github.com/prometheus/client_golang/prometheus/promhttp/http.go b/vendor/github.com/prometheus/client_golang/prometheus/promhttp/http.go new file mode 100644 index 000000000..cea5a90fd --- /dev/null +++ b/vendor/github.com/prometheus/client_golang/prometheus/promhttp/http.go @@ -0,0 +1,349 @@ +// 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 promhttp provides tooling around HTTP servers and clients. +// +// First, the package allows the creation of http.Handler instances to expose +// Prometheus metrics via HTTP. promhttp.Handler acts on the +// prometheus.DefaultGatherer. With HandlerFor, you can create a handler for a +// custom registry or anything that implements the Gatherer interface. It also +// allows the creation of handlers that act differently on errors or allow to +// log errors. +// +// Second, the package provides tooling to instrument instances of http.Handler +// via middleware. Middleware wrappers follow the naming scheme +// InstrumentHandlerX, where X describes the intended use of the middleware. +// See each function's doc comment for specific details. +// +// Finally, the package allows for an http.RoundTripper to be instrumented via +// middleware. Middleware wrappers follow the naming scheme +// InstrumentRoundTripperX, where X describes the intended use of the +// middleware. See each function's doc comment for specific details. +package promhttp + +import ( + "compress/gzip" + "fmt" + "io" + "net/http" + "strings" + "sync" + "time" + + "github.com/prometheus/common/expfmt" + + "github.com/prometheus/client_golang/prometheus" +) + +const ( + contentTypeHeader = "Content-Type" + contentEncodingHeader = "Content-Encoding" + acceptEncodingHeader = "Accept-Encoding" +) + +var gzipPool = sync.Pool{ + New: func() interface{} { + return gzip.NewWriter(nil) + }, +} + +// Handler returns an http.Handler for the prometheus.DefaultGatherer, using +// default HandlerOpts, i.e. it reports the first error as an HTTP error, it has +// no error logging, and it applies compression if requested by the client. +// +// The returned http.Handler is already instrumented using the +// InstrumentMetricHandler function and the prometheus.DefaultRegisterer. If you +// create multiple http.Handlers by separate calls of the Handler function, the +// metrics used for instrumentation will be shared between them, providing +// global scrape counts. +// +// This function is meant to cover the bulk of basic use cases. If you are doing +// anything that requires more customization (including using a non-default +// Gatherer, different instrumentation, and non-default HandlerOpts), use the +// HandlerFor function. See there for details. +func Handler() http.Handler { + return InstrumentMetricHandler( + prometheus.DefaultRegisterer, HandlerFor(prometheus.DefaultGatherer, HandlerOpts{}), + ) +} + +// HandlerFor returns an uninstrumented http.Handler for the provided +// Gatherer. The behavior of the Handler is defined by the provided +// HandlerOpts. Thus, HandlerFor is useful to create http.Handlers for custom +// Gatherers, with non-default HandlerOpts, and/or with custom (or no) +// instrumentation. Use the InstrumentMetricHandler function to apply the same +// kind of instrumentation as it is used by the Handler function. +func HandlerFor(reg prometheus.Gatherer, opts HandlerOpts) http.Handler { + var ( + inFlightSem chan struct{} + errCnt = prometheus.NewCounterVec( + prometheus.CounterOpts{ + Name: "promhttp_metric_handler_errors_total", + Help: "Total number of internal errors encountered by the promhttp metric handler.", + }, + []string{"cause"}, + ) + ) + + if opts.MaxRequestsInFlight > 0 { + inFlightSem = make(chan struct{}, opts.MaxRequestsInFlight) + } + if opts.Registry != nil { + // Initialize all possibilites that can occur below. + errCnt.WithLabelValues("gathering") + errCnt.WithLabelValues("encoding") + if err := opts.Registry.Register(errCnt); err != nil { + if are, ok := err.(prometheus.AlreadyRegisteredError); ok { + errCnt = are.ExistingCollector.(*prometheus.CounterVec) + } else { + panic(err) + } + } + } + + h := http.HandlerFunc(func(rsp http.ResponseWriter, req *http.Request) { + if inFlightSem != nil { + select { + case inFlightSem <- struct{}{}: // All good, carry on. + defer func() { <-inFlightSem }() + default: + http.Error(rsp, fmt.Sprintf( + "Limit of concurrent requests reached (%d), try again later.", opts.MaxRequestsInFlight, + ), http.StatusServiceUnavailable) + return + } + } + mfs, err := reg.Gather() + if err != nil { + if opts.ErrorLog != nil { + opts.ErrorLog.Println("error gathering metrics:", err) + } + errCnt.WithLabelValues("gathering").Inc() + switch opts.ErrorHandling { + case PanicOnError: + panic(err) + case ContinueOnError: + if len(mfs) == 0 { + // Still report the error if no metrics have been gathered. + httpError(rsp, err) + return + } + case HTTPErrorOnError: + httpError(rsp, err) + return + } + } + + contentType := expfmt.Negotiate(req.Header) + header := rsp.Header() + header.Set(contentTypeHeader, string(contentType)) + + w := io.Writer(rsp) + if !opts.DisableCompression && gzipAccepted(req.Header) { + header.Set(contentEncodingHeader, "gzip") + gz := gzipPool.Get().(*gzip.Writer) + defer gzipPool.Put(gz) + + gz.Reset(w) + defer gz.Close() + + w = gz + } + + enc := expfmt.NewEncoder(w, contentType) + + var lastErr error + for _, mf := range mfs { + if err := enc.Encode(mf); err != nil { + lastErr = err + if opts.ErrorLog != nil { + opts.ErrorLog.Println("error encoding and sending metric family:", err) + } + errCnt.WithLabelValues("encoding").Inc() + switch opts.ErrorHandling { + case PanicOnError: + panic(err) + case ContinueOnError: + // Handled later. + case HTTPErrorOnError: + httpError(rsp, err) + return + } + } + } + + if lastErr != nil { + httpError(rsp, lastErr) + } + }) + + if opts.Timeout <= 0 { + return h + } + return http.TimeoutHandler(h, opts.Timeout, fmt.Sprintf( + "Exceeded configured timeout of %v.\n", + opts.Timeout, + )) +} + +// InstrumentMetricHandler is usually used with an http.Handler returned by the +// HandlerFor function. It instruments the provided http.Handler with two +// metrics: A counter vector "promhttp_metric_handler_requests_total" to count +// scrapes partitioned by HTTP status code, and a gauge +// "promhttp_metric_handler_requests_in_flight" to track the number of +// simultaneous scrapes. This function idempotently registers collectors for +// both metrics with the provided Registerer. It panics if the registration +// fails. The provided metrics are useful to see how many scrapes hit the +// monitored target (which could be from different Prometheus servers or other +// scrapers), and how often they overlap (which would result in more than one +// scrape in flight at the same time). Note that the scrapes-in-flight gauge +// will contain the scrape by which it is exposed, while the scrape counter will +// only get incremented after the scrape is complete (as only then the status +// code is known). For tracking scrape durations, use the +// "scrape_duration_seconds" gauge created by the Prometheus server upon each +// scrape. +func InstrumentMetricHandler(reg prometheus.Registerer, handler http.Handler) http.Handler { + cnt := prometheus.NewCounterVec( + prometheus.CounterOpts{ + Name: "promhttp_metric_handler_requests_total", + Help: "Total number of scrapes by HTTP status code.", + }, + []string{"code"}, + ) + // Initialize the most likely HTTP status codes. + cnt.WithLabelValues("200") + cnt.WithLabelValues("500") + cnt.WithLabelValues("503") + if err := reg.Register(cnt); err != nil { + if are, ok := err.(prometheus.AlreadyRegisteredError); ok { + cnt = are.ExistingCollector.(*prometheus.CounterVec) + } else { + panic(err) + } + } + + gge := prometheus.NewGauge(prometheus.GaugeOpts{ + Name: "promhttp_metric_handler_requests_in_flight", + Help: "Current number of scrapes being served.", + }) + if err := reg.Register(gge); err != nil { + if are, ok := err.(prometheus.AlreadyRegisteredError); ok { + gge = are.ExistingCollector.(prometheus.Gauge) + } else { + panic(err) + } + } + + return InstrumentHandlerCounter(cnt, InstrumentHandlerInFlight(gge, handler)) +} + +// HandlerErrorHandling defines how a Handler serving metrics will handle +// errors. +type HandlerErrorHandling int + +// These constants cause handlers serving metrics to behave as described if +// errors are encountered. +const ( + // Serve an HTTP status code 500 upon the first error + // encountered. Report the error message in the body. + HTTPErrorOnError HandlerErrorHandling = iota + // Ignore errors and try to serve as many metrics as possible. However, + // if no metrics can be served, serve an HTTP status code 500 and the + // last error message in the body. Only use this in deliberate "best + // effort" metrics collection scenarios. In this case, it is highly + // recommended to provide other means of detecting errors: By setting an + // ErrorLog in HandlerOpts, the errors are logged. By providing a + // Registry in HandlerOpts, the exposed metrics include an error counter + // "promhttp_metric_handler_errors_total", which can be used for + // alerts. + ContinueOnError + // Panic upon the first error encountered (useful for "crash only" apps). + PanicOnError +) + +// Logger is the minimal interface HandlerOpts needs for logging. Note that +// log.Logger from the standard library implements this interface, and it is +// easy to implement by custom loggers, if they don't do so already anyway. +type Logger interface { + Println(v ...interface{}) +} + +// HandlerOpts specifies options how to serve metrics via an http.Handler. The +// zero value of HandlerOpts is a reasonable default. +type HandlerOpts struct { + // ErrorLog specifies an optional logger for errors collecting and + // serving metrics. If nil, errors are not logged at all. + ErrorLog Logger + // ErrorHandling defines how errors are handled. Note that errors are + // logged regardless of the configured ErrorHandling provided ErrorLog + // is not nil. + ErrorHandling HandlerErrorHandling + // If Registry is not nil, it is used to register a metric + // "promhttp_metric_handler_errors_total", partitioned by "cause". A + // failed registration causes a panic. Note that this error counter is + // different from the instrumentation you get from the various + // InstrumentHandler... helpers. It counts errors that don't necessarily + // result in a non-2xx HTTP status code. There are two typical cases: + // (1) Encoding errors that only happen after streaming of the HTTP body + // has already started (and the status code 200 has been sent). This + // should only happen with custom collectors. (2) Collection errors with + // no effect on the HTTP status code because ErrorHandling is set to + // ContinueOnError. + Registry prometheus.Registerer + // If DisableCompression is true, the handler will never compress the + // response, even if requested by the client. + DisableCompression bool + // The number of concurrent HTTP requests is limited to + // MaxRequestsInFlight. Additional requests are responded to with 503 + // Service Unavailable and a suitable message in the body. If + // MaxRequestsInFlight is 0 or negative, no limit is applied. + MaxRequestsInFlight int + // If handling a request takes longer than Timeout, it is responded to + // with 503 ServiceUnavailable and a suitable Message. No timeout is + // applied if Timeout is 0 or negative. Note that with the current + // implementation, reaching the timeout simply ends the HTTP requests as + // described above (and even that only if sending of the body hasn't + // started yet), while the bulk work of gathering all the metrics keeps + // running in the background (with the eventual result to be thrown + // away). Until the implementation is improved, it is recommended to + // implement a separate timeout in potentially slow Collectors. + Timeout time.Duration +} + +// gzipAccepted returns whether the client will accept gzip-encoded content. +func gzipAccepted(header http.Header) bool { + a := header.Get(acceptEncodingHeader) + parts := strings.Split(a, ",") + for _, part := range parts { + part = strings.TrimSpace(part) + if part == "gzip" || strings.HasPrefix(part, "gzip;") { + return true + } + } + return false +} + +// httpError removes any content-encoding header and then calls http.Error with +// the provided error and http.StatusInternalServerErrer. Error contents is +// supposed to be uncompressed plain text. However, same as with a plain +// http.Error, any header settings will be void if the header has already been +// sent. The error message will still be written to the writer, but it will +// probably be of limited use. +func httpError(rsp http.ResponseWriter, err error) { + rsp.Header().Del(contentEncodingHeader) + http.Error( + rsp, + "An error has occurred while serving metrics:\n\n"+err.Error(), + http.StatusInternalServerError, + ) +} diff --git a/vendor/github.com/prometheus/client_golang/prometheus/promhttp/instrument_client.go b/vendor/github.com/prometheus/client_golang/prometheus/promhttp/instrument_client.go new file mode 100644 index 000000000..83c49b66a --- /dev/null +++ b/vendor/github.com/prometheus/client_golang/prometheus/promhttp/instrument_client.go @@ -0,0 +1,219 @@ +// Copyright 2017 The Prometheus Authors +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package promhttp + +import ( + "crypto/tls" + "net/http" + "net/http/httptrace" + "time" + + "github.com/prometheus/client_golang/prometheus" +) + +// The RoundTripperFunc type is an adapter to allow the use of ordinary +// functions as RoundTrippers. If f is a function with the appropriate +// signature, RountTripperFunc(f) is a RoundTripper that calls f. +type RoundTripperFunc func(req *http.Request) (*http.Response, error) + +// RoundTrip implements the RoundTripper interface. +func (rt RoundTripperFunc) RoundTrip(r *http.Request) (*http.Response, error) { + return rt(r) +} + +// InstrumentRoundTripperInFlight is a middleware that wraps the provided +// http.RoundTripper. It sets the provided prometheus.Gauge to the number of +// requests currently handled by the wrapped http.RoundTripper. +// +// See the example for ExampleInstrumentRoundTripperDuration for example usage. +func InstrumentRoundTripperInFlight(gauge prometheus.Gauge, next http.RoundTripper) RoundTripperFunc { + return RoundTripperFunc(func(r *http.Request) (*http.Response, error) { + gauge.Inc() + defer gauge.Dec() + return next.RoundTrip(r) + }) +} + +// InstrumentRoundTripperCounter is a middleware that wraps the provided +// http.RoundTripper to observe the request result with the provided CounterVec. +// The CounterVec must have zero, one, or two non-const non-curried labels. For +// those, the only allowed label names are "code" and "method". The function +// panics otherwise. Partitioning of the CounterVec happens by HTTP status code +// and/or HTTP method if the respective instance label names are present in the +// CounterVec. For unpartitioned counting, use a CounterVec with zero labels. +// +// If the wrapped RoundTripper panics or returns a non-nil error, the Counter +// is not incremented. +// +// See the example for ExampleInstrumentRoundTripperDuration for example usage. +func InstrumentRoundTripperCounter(counter *prometheus.CounterVec, next http.RoundTripper) RoundTripperFunc { + code, method := checkLabels(counter) + + return RoundTripperFunc(func(r *http.Request) (*http.Response, error) { + resp, err := next.RoundTrip(r) + if err == nil { + counter.With(labels(code, method, r.Method, resp.StatusCode)).Inc() + } + return resp, err + }) +} + +// InstrumentRoundTripperDuration is a middleware that wraps the provided +// http.RoundTripper to observe the request duration with the provided +// ObserverVec. The ObserverVec must have zero, one, or two non-const +// non-curried labels. For those, the only allowed label names are "code" and +// "method". The function panics otherwise. The Observe method of the Observer +// in the ObserverVec is called with the request duration in +// seconds. Partitioning happens by HTTP status code and/or HTTP method if the +// respective instance label names are present in the ObserverVec. For +// unpartitioned observations, use an ObserverVec with zero labels. Note that +// partitioning of Histograms is expensive and should be used judiciously. +// +// If the wrapped RoundTripper panics or returns a non-nil error, no values are +// reported. +// +// Note that this method is only guaranteed to never observe negative durations +// if used with Go1.9+. +func InstrumentRoundTripperDuration(obs prometheus.ObserverVec, next http.RoundTripper) RoundTripperFunc { + code, method := checkLabels(obs) + + return RoundTripperFunc(func(r *http.Request) (*http.Response, error) { + start := time.Now() + resp, err := next.RoundTrip(r) + if err == nil { + obs.With(labels(code, method, r.Method, resp.StatusCode)).Observe(time.Since(start).Seconds()) + } + return resp, err + }) +} + +// InstrumentTrace is used to offer flexibility in instrumenting the available +// httptrace.ClientTrace hook functions. Each function is passed a float64 +// representing the time in seconds since the start of the http request. A user +// may choose to use separately buckets Histograms, or implement custom +// instance labels on a per function basis. +type InstrumentTrace struct { + GotConn func(float64) + PutIdleConn func(float64) + GotFirstResponseByte func(float64) + Got100Continue func(float64) + DNSStart func(float64) + DNSDone func(float64) + ConnectStart func(float64) + ConnectDone func(float64) + TLSHandshakeStart func(float64) + TLSHandshakeDone func(float64) + WroteHeaders func(float64) + Wait100Continue func(float64) + WroteRequest func(float64) +} + +// InstrumentRoundTripperTrace is a middleware that wraps the provided +// RoundTripper and reports times to hook functions provided in the +// InstrumentTrace struct. Hook functions that are not present in the provided +// InstrumentTrace struct are ignored. Times reported to the hook functions are +// time since the start of the request. Only with Go1.9+, those times are +// guaranteed to never be negative. (Earlier Go versions are not using a +// monotonic clock.) Note that partitioning of Histograms is expensive and +// should be used judiciously. +// +// For hook functions that receive an error as an argument, no observations are +// made in the event of a non-nil error value. +// +// See the example for ExampleInstrumentRoundTripperDuration for example usage. +func InstrumentRoundTripperTrace(it *InstrumentTrace, next http.RoundTripper) RoundTripperFunc { + return RoundTripperFunc(func(r *http.Request) (*http.Response, error) { + start := time.Now() + + trace := &httptrace.ClientTrace{ + GotConn: func(_ httptrace.GotConnInfo) { + if it.GotConn != nil { + it.GotConn(time.Since(start).Seconds()) + } + }, + PutIdleConn: func(err error) { + if err != nil { + return + } + if it.PutIdleConn != nil { + it.PutIdleConn(time.Since(start).Seconds()) + } + }, + DNSStart: func(_ httptrace.DNSStartInfo) { + if it.DNSStart != nil { + it.DNSStart(time.Since(start).Seconds()) + } + }, + DNSDone: func(_ httptrace.DNSDoneInfo) { + if it.DNSDone != nil { + it.DNSDone(time.Since(start).Seconds()) + } + }, + ConnectStart: func(_, _ string) { + if it.ConnectStart != nil { + it.ConnectStart(time.Since(start).Seconds()) + } + }, + ConnectDone: func(_, _ string, err error) { + if err != nil { + return + } + if it.ConnectDone != nil { + it.ConnectDone(time.Since(start).Seconds()) + } + }, + GotFirstResponseByte: func() { + if it.GotFirstResponseByte != nil { + it.GotFirstResponseByte(time.Since(start).Seconds()) + } + }, + Got100Continue: func() { + if it.Got100Continue != nil { + it.Got100Continue(time.Since(start).Seconds()) + } + }, + TLSHandshakeStart: func() { + if it.TLSHandshakeStart != nil { + it.TLSHandshakeStart(time.Since(start).Seconds()) + } + }, + TLSHandshakeDone: func(_ tls.ConnectionState, err error) { + if err != nil { + return + } + if it.TLSHandshakeDone != nil { + it.TLSHandshakeDone(time.Since(start).Seconds()) + } + }, + WroteHeaders: func() { + if it.WroteHeaders != nil { + it.WroteHeaders(time.Since(start).Seconds()) + } + }, + Wait100Continue: func() { + if it.Wait100Continue != nil { + it.Wait100Continue(time.Since(start).Seconds()) + } + }, + WroteRequest: func(_ httptrace.WroteRequestInfo) { + if it.WroteRequest != nil { + it.WroteRequest(time.Since(start).Seconds()) + } + }, + } + r = r.WithContext(httptrace.WithClientTrace(r.Context(), trace)) + + return next.RoundTrip(r) + }) +} diff --git a/vendor/github.com/prometheus/client_golang/prometheus/promhttp/instrument_server.go b/vendor/github.com/prometheus/client_golang/prometheus/promhttp/instrument_server.go new file mode 100644 index 000000000..9db243805 --- /dev/null +++ b/vendor/github.com/prometheus/client_golang/prometheus/promhttp/instrument_server.go @@ -0,0 +1,447 @@ +// Copyright 2017 The Prometheus Authors +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package promhttp + +import ( + "errors" + "net/http" + "strconv" + "strings" + "time" + + dto "github.com/prometheus/client_model/go" + + "github.com/prometheus/client_golang/prometheus" +) + +// magicString is used for the hacky label test in checkLabels. Remove once fixed. +const magicString = "zZgWfBxLqvG8kc8IMv3POi2Bb0tZI3vAnBx+gBaFi9FyPzB/CzKUer1yufDa" + +// InstrumentHandlerInFlight is a middleware that wraps the provided +// http.Handler. It sets the provided prometheus.Gauge to the number of +// requests currently handled by the wrapped http.Handler. +// +// See the example for InstrumentHandlerDuration for example usage. +func InstrumentHandlerInFlight(g prometheus.Gauge, next http.Handler) http.Handler { + return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) { + g.Inc() + defer g.Dec() + next.ServeHTTP(w, r) + }) +} + +// InstrumentHandlerDuration is a middleware that wraps the provided +// http.Handler to observe the request duration with the provided ObserverVec. +// The ObserverVec must have zero, one, or two non-const non-curried labels. For +// those, the only allowed label names are "code" and "method". The function +// panics otherwise. The Observe method of the Observer in the ObserverVec is +// called with the request duration in seconds. Partitioning happens by HTTP +// status code and/or HTTP method if the respective instance label names are +// present in the ObserverVec. For unpartitioned observations, use an +// ObserverVec with zero labels. Note that partitioning of Histograms is +// expensive and should be used judiciously. +// +// If the wrapped Handler does not set a status code, a status code of 200 is assumed. +// +// If the wrapped Handler panics, no values are reported. +// +// Note that this method is only guaranteed to never observe negative durations +// if used with Go1.9+. +func InstrumentHandlerDuration(obs prometheus.ObserverVec, next http.Handler) http.HandlerFunc { + code, method := checkLabels(obs) + + if code { + return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) { + now := time.Now() + d := newDelegator(w, nil) + next.ServeHTTP(d, r) + + obs.With(labels(code, method, r.Method, d.Status())).Observe(time.Since(now).Seconds()) + }) + } + + return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) { + now := time.Now() + next.ServeHTTP(w, r) + obs.With(labels(code, method, r.Method, 0)).Observe(time.Since(now).Seconds()) + }) +} + +// InstrumentHandlerCounter is a middleware that wraps the provided http.Handler +// to observe the request result with the provided CounterVec. The CounterVec +// must have zero, one, or two non-const non-curried labels. For those, the only +// allowed label names are "code" and "method". The function panics +// otherwise. Partitioning of the CounterVec happens by HTTP status code and/or +// HTTP method if the respective instance label names are present in the +// CounterVec. For unpartitioned counting, use a CounterVec with zero labels. +// +// If the wrapped Handler does not set a status code, a status code of 200 is assumed. +// +// If the wrapped Handler panics, the Counter is not incremented. +// +// See the example for InstrumentHandlerDuration for example usage. +func InstrumentHandlerCounter(counter *prometheus.CounterVec, next http.Handler) http.HandlerFunc { + code, method := checkLabels(counter) + + if code { + return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) { + d := newDelegator(w, nil) + next.ServeHTTP(d, r) + counter.With(labels(code, method, r.Method, d.Status())).Inc() + }) + } + + return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) { + next.ServeHTTP(w, r) + counter.With(labels(code, method, r.Method, 0)).Inc() + }) +} + +// InstrumentHandlerTimeToWriteHeader is a middleware that wraps the provided +// http.Handler to observe with the provided ObserverVec the request duration +// until the response headers are written. The ObserverVec must have zero, one, +// or two non-const non-curried labels. For those, the only allowed label names +// are "code" and "method". The function panics otherwise. The Observe method of +// the Observer in the ObserverVec is called with the request duration in +// seconds. Partitioning happens by HTTP status code and/or HTTP method if the +// respective instance label names are present in the ObserverVec. For +// unpartitioned observations, use an ObserverVec with zero labels. Note that +// partitioning of Histograms is expensive and should be used judiciously. +// +// If the wrapped Handler panics before calling WriteHeader, no value is +// reported. +// +// Note that this method is only guaranteed to never observe negative durations +// if used with Go1.9+. +// +// See the example for InstrumentHandlerDuration for example usage. +func InstrumentHandlerTimeToWriteHeader(obs prometheus.ObserverVec, next http.Handler) http.HandlerFunc { + code, method := checkLabels(obs) + + return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) { + now := time.Now() + d := newDelegator(w, func(status int) { + obs.With(labels(code, method, r.Method, status)).Observe(time.Since(now).Seconds()) + }) + next.ServeHTTP(d, r) + }) +} + +// InstrumentHandlerRequestSize is a middleware that wraps the provided +// http.Handler to observe the request size with the provided ObserverVec. The +// ObserverVec must have zero, one, or two non-const non-curried labels. For +// those, the only allowed label names are "code" and "method". The function +// panics otherwise. The Observe method of the Observer in the ObserverVec is +// called with the request size in bytes. Partitioning happens by HTTP status +// code and/or HTTP method if the respective instance label names are present in +// the ObserverVec. For unpartitioned observations, use an ObserverVec with zero +// labels. Note that partitioning of Histograms is expensive and should be used +// judiciously. +// +// If the wrapped Handler does not set a status code, a status code of 200 is assumed. +// +// If the wrapped Handler panics, no values are reported. +// +// See the example for InstrumentHandlerDuration for example usage. +func InstrumentHandlerRequestSize(obs prometheus.ObserverVec, next http.Handler) http.HandlerFunc { + code, method := checkLabels(obs) + + if code { + return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) { + d := newDelegator(w, nil) + next.ServeHTTP(d, r) + size := computeApproximateRequestSize(r) + obs.With(labels(code, method, r.Method, d.Status())).Observe(float64(size)) + }) + } + + return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) { + next.ServeHTTP(w, r) + size := computeApproximateRequestSize(r) + obs.With(labels(code, method, r.Method, 0)).Observe(float64(size)) + }) +} + +// InstrumentHandlerResponseSize is a middleware that wraps the provided +// http.Handler to observe the response size with the provided ObserverVec. The +// ObserverVec must have zero, one, or two non-const non-curried labels. For +// those, the only allowed label names are "code" and "method". The function +// panics otherwise. The Observe method of the Observer in the ObserverVec is +// called with the response size in bytes. Partitioning happens by HTTP status +// code and/or HTTP method if the respective instance label names are present in +// the ObserverVec. For unpartitioned observations, use an ObserverVec with zero +// labels. Note that partitioning of Histograms is expensive and should be used +// judiciously. +// +// If the wrapped Handler does not set a status code, a status code of 200 is assumed. +// +// If the wrapped Handler panics, no values are reported. +// +// See the example for InstrumentHandlerDuration for example usage. +func InstrumentHandlerResponseSize(obs prometheus.ObserverVec, next http.Handler) http.Handler { + code, method := checkLabels(obs) + return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) { + d := newDelegator(w, nil) + next.ServeHTTP(d, r) + obs.With(labels(code, method, r.Method, d.Status())).Observe(float64(d.Written())) + }) +} + +func checkLabels(c prometheus.Collector) (code bool, method bool) { + // TODO(beorn7): Remove this hacky way to check for instance labels + // once Descriptors can have their dimensionality queried. + var ( + desc *prometheus.Desc + m prometheus.Metric + pm dto.Metric + lvs []string + ) + + // Get the Desc from the Collector. + descc := make(chan *prometheus.Desc, 1) + c.Describe(descc) + + select { + case desc = <-descc: + default: + panic("no description provided by collector") + } + select { + case <-descc: + panic("more than one description provided by collector") + default: + } + + close(descc) + + // Create a ConstMetric with the Desc. Since we don't know how many + // variable labels there are, try for as long as it needs. + for err := errors.New("dummy"); err != nil; lvs = append(lvs, magicString) { + m, err = prometheus.NewConstMetric(desc, prometheus.UntypedValue, 0, lvs...) + } + + // Write out the metric into a proto message and look at the labels. + // If the value is not the magicString, it is a constLabel, which doesn't interest us. + // If the label is curried, it doesn't interest us. + // In all other cases, only "code" or "method" is allowed. + if err := m.Write(&pm); err != nil { + panic("error checking metric for labels") + } + for _, label := range pm.Label { + name, value := label.GetName(), label.GetValue() + if value != magicString || isLabelCurried(c, name) { + continue + } + switch name { + case "code": + code = true + case "method": + method = true + default: + panic("metric partitioned with non-supported labels") + } + } + return +} + +func isLabelCurried(c prometheus.Collector, label string) bool { + // This is even hackier than the label test above. + // We essentially try to curry again and see if it works. + // But for that, we need to type-convert to the two + // types we use here, ObserverVec or *CounterVec. + switch v := c.(type) { + case *prometheus.CounterVec: + if _, err := v.CurryWith(prometheus.Labels{label: "dummy"}); err == nil { + return false + } + case prometheus.ObserverVec: + if _, err := v.CurryWith(prometheus.Labels{label: "dummy"}); err == nil { + return false + } + default: + panic("unsupported metric vec type") + } + return true +} + +// emptyLabels is a one-time allocation for non-partitioned metrics to avoid +// unnecessary allocations on each request. +var emptyLabels = prometheus.Labels{} + +func labels(code, method bool, reqMethod string, status int) prometheus.Labels { + if !(code || method) { + return emptyLabels + } + labels := prometheus.Labels{} + + if code { + labels["code"] = sanitizeCode(status) + } + if method { + labels["method"] = sanitizeMethod(reqMethod) + } + + return labels +} + +func computeApproximateRequestSize(r *http.Request) int { + s := 0 + if r.URL != nil { + s += len(r.URL.String()) + } + + 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) + } + return s +} + +func sanitizeMethod(m string) string { + switch m { + case "GET", "get": + return "get" + case "PUT", "put": + return "put" + case "HEAD", "head": + return "head" + case "POST", "post": + return "post" + case "DELETE", "delete": + return "delete" + case "CONNECT", "connect": + return "connect" + case "OPTIONS", "options": + return "options" + case "NOTIFY", "notify": + return "notify" + default: + return strings.ToLower(m) + } +} + +// If the wrapped http.Handler has not set a status code, i.e. the value is +// currently 0, santizeCode will return 200, for consistency with behavior in +// the stdlib. +func sanitizeCode(s int) string { + switch s { + case 100: + return "100" + case 101: + return "101" + + case 200, 0: + return "200" + case 201: + return "201" + case 202: + return "202" + case 203: + return "203" + case 204: + return "204" + case 205: + return "205" + case 206: + return "206" + + case 300: + return "300" + case 301: + return "301" + case 302: + return "302" + case 304: + return "304" + case 305: + return "305" + case 307: + return "307" + + case 400: + return "400" + case 401: + return "401" + case 402: + return "402" + case 403: + return "403" + case 404: + return "404" + case 405: + return "405" + case 406: + return "406" + case 407: + return "407" + case 408: + return "408" + case 409: + return "409" + case 410: + return "410" + case 411: + return "411" + case 412: + return "412" + case 413: + return "413" + case 414: + return "414" + case 415: + return "415" + case 416: + return "416" + case 417: + return "417" + case 418: + return "418" + + case 500: + return "500" + case 501: + return "501" + case 502: + return "502" + case 503: + return "503" + case 504: + return "504" + case 505: + return "505" + + case 428: + return "428" + case 429: + return "429" + case 431: + return "431" + case 511: + return "511" + + default: + return strconv.Itoa(s) + } +} diff --git a/vendor/github.com/prometheus/client_golang/prometheus/registry.go b/vendor/github.com/prometheus/client_golang/prometheus/registry.go new file mode 100644 index 000000000..6c32516aa --- /dev/null +++ b/vendor/github.com/prometheus/client_golang/prometheus/registry.go @@ -0,0 +1,945 @@ +// 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 prometheus + +import ( + "bytes" + "fmt" + "io/ioutil" + "os" + "path/filepath" + "runtime" + "sort" + "strings" + "sync" + "unicode/utf8" + + "github.com/golang/protobuf/proto" + "github.com/prometheus/common/expfmt" + + dto "github.com/prometheus/client_model/go" + + "github.com/prometheus/client_golang/prometheus/internal" +) + +const ( + // Capacity for the channel to collect metrics and descriptors. + capMetricChan = 1000 + capDescChan = 10 +) + +// DefaultRegisterer and DefaultGatherer are the implementations of the +// Registerer and Gatherer interface a number of convenience functions in this +// package act on. Initially, both variables point to the same Registry, which +// has a process collector (currently on Linux only, see NewProcessCollector) +// and a Go collector (see NewGoCollector, in particular the note about +// stop-the-world implication with Go versions older than 1.9) already +// registered. This approach to keep default instances as global state mirrors +// the approach of other packages in the Go standard library. Note that there +// are caveats. Change the variables with caution and only if you understand the +// consequences. Users who want to avoid global state altogether should not use +// the convenience functions and act on custom instances instead. +var ( + defaultRegistry = NewRegistry() + DefaultRegisterer Registerer = defaultRegistry + DefaultGatherer Gatherer = defaultRegistry +) + +func init() { + MustRegister(NewProcessCollector(ProcessCollectorOpts{})) + MustRegister(NewGoCollector()) +} + +// NewRegistry creates a new vanilla Registry without any Collectors +// pre-registered. +func NewRegistry() *Registry { + return &Registry{ + collectorsByID: map[uint64]Collector{}, + descIDs: map[uint64]struct{}{}, + dimHashesByName: map[string]uint64{}, + } +} + +// NewPedanticRegistry returns a registry that checks during collection if each +// collected Metric is consistent with its reported Desc, and if the Desc has +// actually been registered with the registry. Unchecked Collectors (those whose +// Describe methed does not yield any descriptors) are excluded from the check. +// +// Usually, a Registry will be happy as long as the union of all collected +// Metrics is consistent and valid even if some metrics are not consistent with +// their own Desc or a Desc provided by their registered Collector. Well-behaved +// Collectors and Metrics will only provide consistent Descs. This Registry is +// useful to test the implementation of Collectors and Metrics. +func NewPedanticRegistry() *Registry { + r := NewRegistry() + r.pedanticChecksEnabled = true + return r +} + +// Registerer is the interface for the part of a registry in charge of +// registering and unregistering. Users of custom registries should use +// Registerer as type for registration purposes (rather than the Registry type +// directly). In that way, they are free to use custom Registerer implementation +// (e.g. for testing purposes). +type Registerer interface { + // Register registers a new Collector to be included in metrics + // collection. It returns an error if the descriptors provided by the + // Collector are invalid or if they — in combination with descriptors of + // already registered Collectors — do not fulfill the consistency and + // uniqueness criteria described in the documentation of metric.Desc. + // + // If the provided Collector is equal to a Collector already registered + // (which includes the case of re-registering the same Collector), the + // returned error is an instance of AlreadyRegisteredError, which + // contains the previously registered Collector. + // + // A Collector whose Describe method does not yield any Desc is treated + // as unchecked. Registration will always succeed. No check for + // re-registering (see previous paragraph) is performed. Thus, the + // caller is responsible for not double-registering the same unchecked + // Collector, and for providing a Collector that will not cause + // inconsistent metrics on collection. (This would lead to scrape + // errors.) + Register(Collector) error + // MustRegister works like Register but registers any number of + // Collectors and panics upon the first registration that causes an + // error. + MustRegister(...Collector) + // Unregister unregisters the Collector that equals the Collector passed + // in as an argument. (Two Collectors are considered equal if their + // Describe method yields the same set of descriptors.) The function + // returns whether a Collector was unregistered. Note that an unchecked + // Collector cannot be unregistered (as its Describe method does not + // yield any descriptor). + // + // Note that even after unregistering, it will not be possible to + // register a new Collector that is inconsistent with the unregistered + // Collector, e.g. a Collector collecting metrics with the same name but + // a different help string. The rationale here is that the same registry + // instance must only collect consistent metrics throughout its + // lifetime. + Unregister(Collector) bool +} + +// Gatherer is the interface for the part of a registry in charge of gathering +// the collected metrics into a number of MetricFamilies. The Gatherer interface +// comes with the same general implication as described for the Registerer +// interface. +type Gatherer interface { + // Gather calls the Collect method of the registered Collectors and then + // gathers the collected metrics into a lexicographically sorted slice + // of uniquely named MetricFamily protobufs. Gather ensures that the + // returned slice is valid and self-consistent so that it can be used + // for valid exposition. As an exception to the strict consistency + // requirements described for metric.Desc, Gather will tolerate + // different sets of label names for metrics of the same metric family. + // + // Even if an error occurs, Gather attempts to gather as many metrics as + // possible. Hence, if a non-nil error is returned, the returned + // MetricFamily slice could be nil (in case of a fatal error that + // prevented any meaningful metric collection) or contain a number of + // MetricFamily protobufs, some of which might be incomplete, and some + // might be missing altogether. The returned error (which might be a + // MultiError) explains the details. Note that this is mostly useful for + // debugging purposes. If the gathered protobufs are to be used for + // exposition in actual monitoring, it is almost always better to not + // expose an incomplete result and instead disregard the returned + // MetricFamily protobufs in case the returned error is non-nil. + Gather() ([]*dto.MetricFamily, error) +} + +// Register registers the provided Collector with the DefaultRegisterer. +// +// Register is a shortcut for DefaultRegisterer.Register(c). See there for more +// details. +func Register(c Collector) error { + return DefaultRegisterer.Register(c) +} + +// MustRegister registers the provided Collectors with the DefaultRegisterer and +// panics if any error occurs. +// +// MustRegister is a shortcut for DefaultRegisterer.MustRegister(cs...). See +// there for more details. +func MustRegister(cs ...Collector) { + DefaultRegisterer.MustRegister(cs...) +} + +// Unregister removes the registration of the provided Collector from the +// DefaultRegisterer. +// +// Unregister is a shortcut for DefaultRegisterer.Unregister(c). See there for +// more details. +func Unregister(c Collector) bool { + return DefaultRegisterer.Unregister(c) +} + +// GathererFunc turns a function into a Gatherer. +type GathererFunc func() ([]*dto.MetricFamily, error) + +// Gather implements Gatherer. +func (gf GathererFunc) Gather() ([]*dto.MetricFamily, error) { + return gf() +} + +// AlreadyRegisteredError is returned by the Register method if the Collector to +// be registered has already been registered before, or a different Collector +// that collects the same metrics has been registered before. Registration fails +// in that case, but you can detect from the kind of error what has +// happened. The error contains fields for the existing Collector and the +// (rejected) new Collector that equals the existing one. This can be used to +// find out if an equal Collector has been registered before and switch over to +// using the old one, as demonstrated in the example. +type AlreadyRegisteredError struct { + ExistingCollector, NewCollector Collector +} + +func (err AlreadyRegisteredError) Error() string { + return "duplicate metrics collector registration attempted" +} + +// MultiError is a slice of errors implementing the error interface. It is used +// by a Gatherer to report multiple errors during MetricFamily gathering. +type MultiError []error + +func (errs MultiError) Error() string { + if len(errs) == 0 { + return "" + } + buf := &bytes.Buffer{} + fmt.Fprintf(buf, "%d error(s) occurred:", len(errs)) + for _, err := range errs { + fmt.Fprintf(buf, "\n* %s", err) + } + return buf.String() +} + +// Append appends the provided error if it is not nil. +func (errs *MultiError) Append(err error) { + if err != nil { + *errs = append(*errs, err) + } +} + +// MaybeUnwrap returns nil if len(errs) is 0. It returns the first and only +// contained error as error if len(errs is 1). In all other cases, it returns +// the MultiError directly. This is helpful for returning a MultiError in a way +// that only uses the MultiError if needed. +func (errs MultiError) MaybeUnwrap() error { + switch len(errs) { + case 0: + return nil + case 1: + return errs[0] + default: + return errs + } +} + +// Registry registers Prometheus collectors, collects their metrics, and gathers +// them into MetricFamilies for exposition. It implements both Registerer and +// Gatherer. The zero value is not usable. Create instances with NewRegistry or +// NewPedanticRegistry. +type Registry struct { + mtx sync.RWMutex + collectorsByID map[uint64]Collector // ID is a hash of the descIDs. + descIDs map[uint64]struct{} + dimHashesByName map[string]uint64 + uncheckedCollectors []Collector + pedanticChecksEnabled bool +} + +// Register implements Registerer. +func (r *Registry) Register(c Collector) error { + var ( + descChan = make(chan *Desc, capDescChan) + newDescIDs = map[uint64]struct{}{} + newDimHashesByName = map[string]uint64{} + collectorID uint64 // Just a sum of all desc IDs. + duplicateDescErr error + ) + go func() { + c.Describe(descChan) + close(descChan) + }() + r.mtx.Lock() + defer func() { + // Drain channel in case of premature return to not leak a goroutine. + for range descChan { + } + r.mtx.Unlock() + }() + // Conduct various tests... + for desc := range descChan { + + // Is the descriptor valid at all? + if desc.err != nil { + return fmt.Errorf("descriptor %s is invalid: %s", desc, desc.err) + } + + // Is the descID unique? + // (In other words: Is the fqName + constLabel combination unique?) + if _, exists := r.descIDs[desc.id]; exists { + duplicateDescErr = fmt.Errorf("descriptor %s already exists with the same fully-qualified name and const label values", desc) + } + // If it is not a duplicate desc in this collector, add it to + // the collectorID. (We allow duplicate descs within the same + // collector, but their existence must be a no-op.) + if _, exists := newDescIDs[desc.id]; !exists { + newDescIDs[desc.id] = struct{}{} + collectorID += desc.id + } + + // Are all the label names and the help string consistent with + // previous descriptors of the same name? + // First check existing descriptors... + if dimHash, exists := r.dimHashesByName[desc.fqName]; exists { + if dimHash != desc.dimHash { + return fmt.Errorf("a previously registered descriptor with the same fully-qualified name as %s has different label names or a different help string", desc) + } + } else { + // ...then check the new descriptors already seen. + if dimHash, exists := newDimHashesByName[desc.fqName]; exists { + if dimHash != desc.dimHash { + return fmt.Errorf("descriptors reported by collector have inconsistent label names or help strings for the same fully-qualified name, offender is %s", desc) + } + } else { + newDimHashesByName[desc.fqName] = desc.dimHash + } + } + } + // A Collector yielding no Desc at all is considered unchecked. + if len(newDescIDs) == 0 { + r.uncheckedCollectors = append(r.uncheckedCollectors, c) + return nil + } + if existing, exists := r.collectorsByID[collectorID]; exists { + switch e := existing.(type) { + case *wrappingCollector: + return AlreadyRegisteredError{ + ExistingCollector: e.unwrapRecursively(), + NewCollector: c, + } + default: + return AlreadyRegisteredError{ + ExistingCollector: e, + NewCollector: c, + } + } + } + // If the collectorID is new, but at least one of the descs existed + // before, we are in trouble. + if duplicateDescErr != nil { + return duplicateDescErr + } + + // Only after all tests have passed, actually register. + r.collectorsByID[collectorID] = c + for hash := range newDescIDs { + r.descIDs[hash] = struct{}{} + } + for name, dimHash := range newDimHashesByName { + r.dimHashesByName[name] = dimHash + } + return nil +} + +// Unregister implements Registerer. +func (r *Registry) Unregister(c Collector) bool { + var ( + descChan = make(chan *Desc, capDescChan) + descIDs = map[uint64]struct{}{} + collectorID uint64 // Just a sum of the desc IDs. + ) + go func() { + c.Describe(descChan) + close(descChan) + }() + for desc := range descChan { + if _, exists := descIDs[desc.id]; !exists { + collectorID += desc.id + descIDs[desc.id] = struct{}{} + } + } + + r.mtx.RLock() + if _, exists := r.collectorsByID[collectorID]; !exists { + r.mtx.RUnlock() + return false + } + r.mtx.RUnlock() + + r.mtx.Lock() + defer r.mtx.Unlock() + + delete(r.collectorsByID, collectorID) + for id := range descIDs { + delete(r.descIDs, id) + } + // dimHashesByName is left untouched as those must be consistent + // throughout the lifetime of a program. + return true +} + +// MustRegister implements Registerer. +func (r *Registry) MustRegister(cs ...Collector) { + for _, c := range cs { + if err := r.Register(c); err != nil { + panic(err) + } + } +} + +// Gather implements Gatherer. +func (r *Registry) Gather() ([]*dto.MetricFamily, error) { + var ( + checkedMetricChan = make(chan Metric, capMetricChan) + uncheckedMetricChan = make(chan Metric, capMetricChan) + metricHashes = map[uint64]struct{}{} + wg sync.WaitGroup + errs MultiError // The collected errors to return in the end. + registeredDescIDs map[uint64]struct{} // Only used for pedantic checks + ) + + r.mtx.RLock() + goroutineBudget := len(r.collectorsByID) + len(r.uncheckedCollectors) + metricFamiliesByName := make(map[string]*dto.MetricFamily, len(r.dimHashesByName)) + checkedCollectors := make(chan Collector, len(r.collectorsByID)) + uncheckedCollectors := make(chan Collector, len(r.uncheckedCollectors)) + for _, collector := range r.collectorsByID { + checkedCollectors <- collector + } + for _, collector := range r.uncheckedCollectors { + uncheckedCollectors <- collector + } + // In case pedantic checks are enabled, we have to copy the map before + // giving up the RLock. + if r.pedanticChecksEnabled { + registeredDescIDs = make(map[uint64]struct{}, len(r.descIDs)) + for id := range r.descIDs { + registeredDescIDs[id] = struct{}{} + } + } + r.mtx.RUnlock() + + wg.Add(goroutineBudget) + + collectWorker := func() { + for { + select { + case collector := <-checkedCollectors: + collector.Collect(checkedMetricChan) + case collector := <-uncheckedCollectors: + collector.Collect(uncheckedMetricChan) + default: + return + } + wg.Done() + } + } + + // Start the first worker now to make sure at least one is running. + go collectWorker() + goroutineBudget-- + + // Close checkedMetricChan and uncheckedMetricChan once all collectors + // are collected. + go func() { + wg.Wait() + close(checkedMetricChan) + close(uncheckedMetricChan) + }() + + // Drain checkedMetricChan and uncheckedMetricChan in case of premature return. + defer func() { + if checkedMetricChan != nil { + for range checkedMetricChan { + } + } + if uncheckedMetricChan != nil { + for range uncheckedMetricChan { + } + } + }() + + // Copy the channel references so we can nil them out later to remove + // them from the select statements below. + cmc := checkedMetricChan + umc := uncheckedMetricChan + + for { + select { + case metric, ok := <-cmc: + if !ok { + cmc = nil + break + } + errs.Append(processMetric( + metric, metricFamiliesByName, + metricHashes, + registeredDescIDs, + )) + case metric, ok := <-umc: + if !ok { + umc = nil + break + } + errs.Append(processMetric( + metric, metricFamiliesByName, + metricHashes, + nil, + )) + default: + if goroutineBudget <= 0 || len(checkedCollectors)+len(uncheckedCollectors) == 0 { + // All collectors are already being worked on or + // we have already as many goroutines started as + // there are collectors. Do the same as above, + // just without the default. + select { + case metric, ok := <-cmc: + if !ok { + cmc = nil + break + } + errs.Append(processMetric( + metric, metricFamiliesByName, + metricHashes, + registeredDescIDs, + )) + case metric, ok := <-umc: + if !ok { + umc = nil + break + } + errs.Append(processMetric( + metric, metricFamiliesByName, + metricHashes, + nil, + )) + } + break + } + // Start more workers. + go collectWorker() + goroutineBudget-- + runtime.Gosched() + } + // Once both checkedMetricChan and uncheckdMetricChan are closed + // and drained, the contraption above will nil out cmc and umc, + // and then we can leave the collect loop here. + if cmc == nil && umc == nil { + break + } + } + return internal.NormalizeMetricFamilies(metricFamiliesByName), errs.MaybeUnwrap() +} + +// WriteToTextfile calls Gather on the provided Gatherer, encodes the result in the +// Prometheus text format, and writes it to a temporary file. Upon success, the +// temporary file is renamed to the provided filename. +// +// This is intended for use with the textfile collector of the node exporter. +// Note that the node exporter expects the filename to be suffixed with ".prom". +func WriteToTextfile(filename string, g Gatherer) error { + tmp, err := ioutil.TempFile(filepath.Dir(filename), filepath.Base(filename)) + if err != nil { + return err + } + defer os.Remove(tmp.Name()) + + mfs, err := g.Gather() + if err != nil { + return err + } + for _, mf := range mfs { + if _, err := expfmt.MetricFamilyToText(tmp, mf); err != nil { + return err + } + } + if err := tmp.Close(); err != nil { + return err + } + + if err := os.Chmod(tmp.Name(), 0644); err != nil { + return err + } + return os.Rename(tmp.Name(), filename) +} + +// processMetric is an internal helper method only used by the Gather method. +func processMetric( + metric Metric, + metricFamiliesByName map[string]*dto.MetricFamily, + metricHashes map[uint64]struct{}, + registeredDescIDs map[uint64]struct{}, +) error { + desc := metric.Desc() + // Wrapped metrics collected by an unchecked Collector can have an + // invalid Desc. + if desc.err != nil { + return desc.err + } + dtoMetric := &dto.Metric{} + if err := metric.Write(dtoMetric); err != nil { + return fmt.Errorf("error collecting metric %v: %s", desc, err) + } + metricFamily, ok := metricFamiliesByName[desc.fqName] + if ok { // Existing name. + if metricFamily.GetHelp() != desc.help { + return fmt.Errorf( + "collected metric %s %s has help %q but should have %q", + desc.fqName, dtoMetric, desc.help, metricFamily.GetHelp(), + ) + } + // TODO(beorn7): Simplify switch once Desc has type. + switch metricFamily.GetType() { + case dto.MetricType_COUNTER: + if dtoMetric.Counter == nil { + return fmt.Errorf( + "collected metric %s %s should be a Counter", + desc.fqName, dtoMetric, + ) + } + case dto.MetricType_GAUGE: + if dtoMetric.Gauge == nil { + return fmt.Errorf( + "collected metric %s %s should be a Gauge", + desc.fqName, dtoMetric, + ) + } + case dto.MetricType_SUMMARY: + if dtoMetric.Summary == nil { + return fmt.Errorf( + "collected metric %s %s should be a Summary", + desc.fqName, dtoMetric, + ) + } + case dto.MetricType_UNTYPED: + if dtoMetric.Untyped == nil { + return fmt.Errorf( + "collected metric %s %s should be Untyped", + desc.fqName, dtoMetric, + ) + } + case dto.MetricType_HISTOGRAM: + if dtoMetric.Histogram == nil { + return fmt.Errorf( + "collected metric %s %s should be a Histogram", + desc.fqName, dtoMetric, + ) + } + default: + panic("encountered MetricFamily with invalid type") + } + } else { // New name. + metricFamily = &dto.MetricFamily{} + metricFamily.Name = proto.String(desc.fqName) + metricFamily.Help = proto.String(desc.help) + // TODO(beorn7): Simplify switch once Desc has type. + switch { + case dtoMetric.Gauge != nil: + metricFamily.Type = dto.MetricType_GAUGE.Enum() + case dtoMetric.Counter != nil: + metricFamily.Type = dto.MetricType_COUNTER.Enum() + case dtoMetric.Summary != nil: + metricFamily.Type = dto.MetricType_SUMMARY.Enum() + case dtoMetric.Untyped != nil: + metricFamily.Type = dto.MetricType_UNTYPED.Enum() + case dtoMetric.Histogram != nil: + metricFamily.Type = dto.MetricType_HISTOGRAM.Enum() + default: + return fmt.Errorf("empty metric collected: %s", dtoMetric) + } + if err := checkSuffixCollisions(metricFamily, metricFamiliesByName); err != nil { + return err + } + metricFamiliesByName[desc.fqName] = metricFamily + } + if err := checkMetricConsistency(metricFamily, dtoMetric, metricHashes); err != nil { + return err + } + if registeredDescIDs != nil { + // Is the desc registered at all? + if _, exist := registeredDescIDs[desc.id]; !exist { + return fmt.Errorf( + "collected metric %s %s with unregistered descriptor %s", + metricFamily.GetName(), dtoMetric, desc, + ) + } + if err := checkDescConsistency(metricFamily, dtoMetric, desc); err != nil { + return err + } + } + metricFamily.Metric = append(metricFamily.Metric, dtoMetric) + return nil +} + +// Gatherers is a slice of Gatherer instances that implements the Gatherer +// interface itself. Its Gather method calls Gather on all Gatherers in the +// slice in order and returns the merged results. Errors returned from the +// Gather calls are all returned in a flattened MultiError. Duplicate and +// inconsistent Metrics are skipped (first occurrence in slice order wins) and +// reported in the returned error. +// +// Gatherers can be used to merge the Gather results from multiple +// Registries. It also provides a way to directly inject existing MetricFamily +// protobufs into the gathering by creating a custom Gatherer with a Gather +// method that simply returns the existing MetricFamily protobufs. Note that no +// registration is involved (in contrast to Collector registration), so +// obviously registration-time checks cannot happen. Any inconsistencies between +// the gathered MetricFamilies are reported as errors by the Gather method, and +// inconsistent Metrics are dropped. Invalid parts of the MetricFamilies +// (e.g. syntactically invalid metric or label names) will go undetected. +type Gatherers []Gatherer + +// Gather implements Gatherer. +func (gs Gatherers) Gather() ([]*dto.MetricFamily, error) { + var ( + metricFamiliesByName = map[string]*dto.MetricFamily{} + metricHashes = map[uint64]struct{}{} + errs MultiError // The collected errors to return in the end. + ) + + for i, g := range gs { + mfs, err := g.Gather() + if err != nil { + if multiErr, ok := err.(MultiError); ok { + for _, err := range multiErr { + errs = append(errs, fmt.Errorf("[from Gatherer #%d] %s", i+1, err)) + } + } else { + errs = append(errs, fmt.Errorf("[from Gatherer #%d] %s", i+1, err)) + } + } + for _, mf := range mfs { + existingMF, exists := metricFamiliesByName[mf.GetName()] + if exists { + if existingMF.GetHelp() != mf.GetHelp() { + errs = append(errs, fmt.Errorf( + "gathered metric family %s has help %q but should have %q", + mf.GetName(), mf.GetHelp(), existingMF.GetHelp(), + )) + continue + } + if existingMF.GetType() != mf.GetType() { + errs = append(errs, fmt.Errorf( + "gathered metric family %s has type %s but should have %s", + mf.GetName(), mf.GetType(), existingMF.GetType(), + )) + continue + } + } else { + existingMF = &dto.MetricFamily{} + existingMF.Name = mf.Name + existingMF.Help = mf.Help + existingMF.Type = mf.Type + if err := checkSuffixCollisions(existingMF, metricFamiliesByName); err != nil { + errs = append(errs, err) + continue + } + metricFamiliesByName[mf.GetName()] = existingMF + } + for _, m := range mf.Metric { + if err := checkMetricConsistency(existingMF, m, metricHashes); err != nil { + errs = append(errs, err) + continue + } + existingMF.Metric = append(existingMF.Metric, m) + } + } + } + return internal.NormalizeMetricFamilies(metricFamiliesByName), errs.MaybeUnwrap() +} + +// checkSuffixCollisions checks for collisions with the “magic” suffixes the +// Prometheus text format and the internal metric representation of the +// Prometheus server add while flattening Summaries and Histograms. +func checkSuffixCollisions(mf *dto.MetricFamily, mfs map[string]*dto.MetricFamily) error { + var ( + newName = mf.GetName() + newType = mf.GetType() + newNameWithoutSuffix = "" + ) + switch { + case strings.HasSuffix(newName, "_count"): + newNameWithoutSuffix = newName[:len(newName)-6] + case strings.HasSuffix(newName, "_sum"): + newNameWithoutSuffix = newName[:len(newName)-4] + case strings.HasSuffix(newName, "_bucket"): + newNameWithoutSuffix = newName[:len(newName)-7] + } + if newNameWithoutSuffix != "" { + if existingMF, ok := mfs[newNameWithoutSuffix]; ok { + switch existingMF.GetType() { + case dto.MetricType_SUMMARY: + if !strings.HasSuffix(newName, "_bucket") { + return fmt.Errorf( + "collected metric named %q collides with previously collected summary named %q", + newName, newNameWithoutSuffix, + ) + } + case dto.MetricType_HISTOGRAM: + return fmt.Errorf( + "collected metric named %q collides with previously collected histogram named %q", + newName, newNameWithoutSuffix, + ) + } + } + } + if newType == dto.MetricType_SUMMARY || newType == dto.MetricType_HISTOGRAM { + if _, ok := mfs[newName+"_count"]; ok { + return fmt.Errorf( + "collected histogram or summary named %q collides with previously collected metric named %q", + newName, newName+"_count", + ) + } + if _, ok := mfs[newName+"_sum"]; ok { + return fmt.Errorf( + "collected histogram or summary named %q collides with previously collected metric named %q", + newName, newName+"_sum", + ) + } + } + if newType == dto.MetricType_HISTOGRAM { + if _, ok := mfs[newName+"_bucket"]; ok { + return fmt.Errorf( + "collected histogram named %q collides with previously collected metric named %q", + newName, newName+"_bucket", + ) + } + } + return nil +} + +// checkMetricConsistency checks if the provided Metric is consistent with the +// provided MetricFamily. It also hashes the Metric labels and the MetricFamily +// name. If the resulting hash is already in the provided metricHashes, an error +// is returned. If not, it is added to metricHashes. +func checkMetricConsistency( + metricFamily *dto.MetricFamily, + dtoMetric *dto.Metric, + metricHashes map[uint64]struct{}, +) error { + name := metricFamily.GetName() + + // Type consistency with metric family. + if metricFamily.GetType() == dto.MetricType_GAUGE && dtoMetric.Gauge == nil || + metricFamily.GetType() == dto.MetricType_COUNTER && dtoMetric.Counter == nil || + metricFamily.GetType() == dto.MetricType_SUMMARY && dtoMetric.Summary == nil || + metricFamily.GetType() == dto.MetricType_HISTOGRAM && dtoMetric.Histogram == nil || + metricFamily.GetType() == dto.MetricType_UNTYPED && dtoMetric.Untyped == nil { + return fmt.Errorf( + "collected metric %q { %s} is not a %s", + name, dtoMetric, metricFamily.GetType(), + ) + } + + previousLabelName := "" + for _, labelPair := range dtoMetric.GetLabel() { + labelName := labelPair.GetName() + if labelName == previousLabelName { + return fmt.Errorf( + "collected metric %q { %s} has two or more labels with the same name: %s", + name, dtoMetric, labelName, + ) + } + if !checkLabelName(labelName) { + return fmt.Errorf( + "collected metric %q { %s} has a label with an invalid name: %s", + name, dtoMetric, labelName, + ) + } + if dtoMetric.Summary != nil && labelName == quantileLabel { + return fmt.Errorf( + "collected metric %q { %s} must not have an explicit %q label", + name, dtoMetric, quantileLabel, + ) + } + if !utf8.ValidString(labelPair.GetValue()) { + return fmt.Errorf( + "collected metric %q { %s} has a label named %q whose value is not utf8: %#v", + name, dtoMetric, labelName, labelPair.GetValue()) + } + previousLabelName = labelName + } + + // Is the metric unique (i.e. no other metric with the same name and the same labels)? + h := hashNew() + h = hashAdd(h, name) + h = hashAddByte(h, separatorByte) + // Make sure label pairs are sorted. We depend on it for the consistency + // check. + if !sort.IsSorted(labelPairSorter(dtoMetric.Label)) { + // We cannot sort dtoMetric.Label in place as it is immutable by contract. + copiedLabels := make([]*dto.LabelPair, len(dtoMetric.Label)) + copy(copiedLabels, dtoMetric.Label) + sort.Sort(labelPairSorter(copiedLabels)) + dtoMetric.Label = copiedLabels + } + for _, lp := range dtoMetric.Label { + h = hashAdd(h, lp.GetName()) + h = hashAddByte(h, separatorByte) + h = hashAdd(h, lp.GetValue()) + h = hashAddByte(h, separatorByte) + } + if _, exists := metricHashes[h]; exists { + return fmt.Errorf( + "collected metric %q { %s} was collected before with the same name and label values", + name, dtoMetric, + ) + } + metricHashes[h] = struct{}{} + return nil +} + +func checkDescConsistency( + metricFamily *dto.MetricFamily, + dtoMetric *dto.Metric, + desc *Desc, +) error { + // Desc help consistency with metric family help. + if metricFamily.GetHelp() != desc.help { + return fmt.Errorf( + "collected metric %s %s has help %q but should have %q", + metricFamily.GetName(), dtoMetric, metricFamily.GetHelp(), desc.help, + ) + } + + // Is the desc consistent with the content of the metric? + lpsFromDesc := make([]*dto.LabelPair, len(desc.constLabelPairs), len(dtoMetric.Label)) + copy(lpsFromDesc, desc.constLabelPairs) + for _, l := range desc.variableLabels { + lpsFromDesc = append(lpsFromDesc, &dto.LabelPair{ + Name: proto.String(l), + }) + } + if len(lpsFromDesc) != len(dtoMetric.Label) { + return fmt.Errorf( + "labels in collected metric %s %s are inconsistent with descriptor %s", + metricFamily.GetName(), dtoMetric, desc, + ) + } + sort.Sort(labelPairSorter(lpsFromDesc)) + for i, lpFromDesc := range lpsFromDesc { + lpFromMetric := dtoMetric.Label[i] + if lpFromDesc.GetName() != lpFromMetric.GetName() || + lpFromDesc.Value != nil && lpFromDesc.GetValue() != lpFromMetric.GetValue() { + return fmt.Errorf( + "labels in collected metric %s %s are inconsistent with descriptor %s", + metricFamily.GetName(), dtoMetric, desc, + ) + } + } + return nil +} diff --git a/vendor/github.com/prometheus/client_golang/prometheus/summary.go b/vendor/github.com/prometheus/client_golang/prometheus/summary.go new file mode 100644 index 000000000..c970fdee0 --- /dev/null +++ b/vendor/github.com/prometheus/client_golang/prometheus/summary.go @@ -0,0 +1,736 @@ +// 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 prometheus + +import ( + "fmt" + "math" + "runtime" + "sort" + "sync" + "sync/atomic" + "time" + + "github.com/beorn7/perks/quantile" + "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" + +// A Summary captures individual observations from an event or sample stream and +// summarizes them in a manner similar to traditional summary statistics: 1. sum +// of observations, 2. observation count, 3. rank estimations. +// +// A typical use-case is the observation of request latencies. By default, a +// Summary provides the median, the 90th and the 99th percentile of the latency +// as rank estimations. However, the default behavior will change in the +// upcoming v1.0.0 of the library. There will be no rank estimations at all by +// default. For a sane transition, it is recommended to set the desired rank +// estimations explicitly. +// +// Note that the rank estimations cannot be aggregated in a meaningful way with +// the Prometheus query language (i.e. you cannot average or add them). If you +// need aggregatable quantiles (e.g. you want the 99th percentile latency of all +// queries served across all instances of a service), consider the Histogram +// metric type. See the Prometheus documentation for more details. +// +// To create Summary instances, use NewSummary. +type Summary interface { + Metric + Collector + + // Observe adds a single observation to the summary. + Observe(float64) +} + +var errQuantileLabelNotAllowed = fmt.Errorf( + "%q is not allowed as label name in summaries", quantileLabel, +) + +// Default values for SummaryOpts. +const ( + // DefMaxAge is the default duration for which observations stay + // relevant. + DefMaxAge time.Duration = 10 * time.Minute + // DefAgeBuckets is the default number of buckets used to calculate the + // age of observations. + DefAgeBuckets = 5 + // DefBufCap is the standard buffer size for collecting Summary observations. + DefBufCap = 500 +) + +// SummaryOpts bundles the options for creating a Summary metric. It is +// mandatory to set Name to a non-empty string. While all other fields are +// optional and can safely be left at their zero value, it is recommended to set +// a help string and to explicitly set the Objectives field to the desired value +// as the default value will change in the upcoming v1.0.0 of the library. +type SummaryOpts struct { + // Namespace, Subsystem, and Name are components of the fully-qualified + // name of the Summary (created by joining these components with + // "_"). Only Name is mandatory, the others merely help structuring the + // name. Note that the fully-qualified name of the Summary must be a + // valid Prometheus metric name. + Namespace string + Subsystem string + Name string + + // Help provides information about this Summary. + // + // Metrics with the same fully-qualified name must have the same Help + // string. + Help string + + // ConstLabels are used to attach fixed labels to this metric. Metrics + // with the same fully-qualified name must have the same label names in + // their ConstLabels. + // + // Due to the way a Summary is represented in the Prometheus text format + // and how it is handled by the Prometheus server internally, “quantile” + // is an illegal label name. Construction of a Summary or SummaryVec + // will panic if this label name is used in ConstLabels. + // + // ConstLabels are only used rarely. In particular, do not use them to + // attach the same labels to all your metrics. Those use cases are + // better covered by target labels set by the scraping Prometheus + // server, or by one specific metric (e.g. a build_info or a + // machine_role metric). See also + // https://prometheus.io/docs/instrumenting/writing_exporters/#target-labels,-not-static-scraped-labels + 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 an empty map, resulting in a summary without + // quantiles. + Objectives map[float64]float64 + + // MaxAge defines the duration for which an observation stays relevant + // for the summary. Must be positive. The default value is DefMaxAge. + MaxAge time.Duration + + // AgeBuckets is the number of buckets used to exclude observations that + // are older than MaxAge from the summary. A higher number has a + // resource penalty, so only increase it if the higher resolution is + // really required. For very high observation rates, you might want to + // reduce the number of age buckets. With only one age bucket, you will + // effectively see a complete reset of the summary each time MaxAge has + // passed. The default value is DefAgeBuckets. + AgeBuckets uint32 + + // BufCap defines the default sample stream buffer size. The default + // value of DefBufCap should suffice for most uses. If there is a need + // to increase the value, a multiple of 500 is recommended (because that + // is the internal buffer size of the underlying package + // "github.com/bmizerany/perks/quantile"). + BufCap uint32 +} + +// Problem 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 +// on observation time, less effort on scrape time, which is exactly the +// opposite of what we try to accomplish, but at least the results are correct. +// +// The quite elegant previous contraption to merge the age buckets efficiently +// on scrape time (see code up commit 6b9530d72ea715f0ba612c0120e6e09fbf1d49d0) +// can't be used anymore. + +// NewSummary creates a new Summary based on the provided SummaryOpts. +func NewSummary(opts SummaryOpts) Summary { + return newSummary( + NewDesc( + BuildFQName(opts.Namespace, opts.Subsystem, opts.Name), + opts.Help, + nil, + opts.ConstLabels, + ), + opts, + ) +} + +func newSummary(desc *Desc, opts SummaryOpts, labelValues ...string) Summary { + if len(desc.variableLabels) != len(labelValues) { + panic(makeInconsistentCardinalityError(desc.fqName, desc.variableLabels, labelValues)) + } + + for _, n := range desc.variableLabels { + if n == quantileLabel { + panic(errQuantileLabelNotAllowed) + } + } + for _, lp := range desc.constLabelPairs { + if lp.GetName() == quantileLabel { + panic(errQuantileLabelNotAllowed) + } + } + + if opts.Objectives == nil { + opts.Objectives = map[float64]float64{} + } + + if opts.MaxAge < 0 { + panic(fmt.Errorf("illegal max age MaxAge=%v", opts.MaxAge)) + } + if opts.MaxAge == 0 { + opts.MaxAge = DefMaxAge + } + + if opts.AgeBuckets == 0 { + opts.AgeBuckets = DefAgeBuckets + } + + if opts.BufCap == 0 { + opts.BufCap = DefBufCap + } + + if len(opts.Objectives) == 0 { + // Use the lock-free implementation of a Summary without objectives. + s := &noObjectivesSummary{ + desc: desc, + labelPairs: makeLabelPairs(desc, labelValues), + counts: [2]*summaryCounts{&summaryCounts{}, &summaryCounts{}}, + } + s.init(s) // Init self-collection. + return s + } + + s := &summary{ + desc: desc, + + objectives: opts.Objectives, + sortedObjectives: make([]float64, 0, len(opts.Objectives)), + + labelPairs: makeLabelPairs(desc, labelValues), + + hotBuf: make([]float64, 0, opts.BufCap), + coldBuf: make([]float64, 0, opts.BufCap), + streamDuration: opts.MaxAge / time.Duration(opts.AgeBuckets), + } + s.headStreamExpTime = time.Now().Add(s.streamDuration) + s.hotBufExpTime = s.headStreamExpTime + + for i := uint32(0); i < opts.AgeBuckets; i++ { + s.streams = append(s.streams, s.newStream()) + } + s.headStream = s.streams[0] + + for qu := range s.objectives { + s.sortedObjectives = append(s.sortedObjectives, qu) + } + sort.Float64s(s.sortedObjectives) + + s.init(s) // Init self-collection. + return s +} + +type summary struct { + selfCollector + + bufMtx sync.Mutex // Protects hotBuf and hotBufExpTime. + mtx sync.Mutex // Protects every other moving part. + // Lock bufMtx before mtx if both are needed. + + desc *Desc + + objectives map[float64]float64 + sortedObjectives []float64 + + labelPairs []*dto.LabelPair + + sum float64 + cnt uint64 + + hotBuf, coldBuf []float64 + + streams []*quantile.Stream + streamDuration time.Duration + headStream *quantile.Stream + headStreamIdx int + headStreamExpTime, hotBufExpTime time.Time +} + +func (s *summary) Desc() *Desc { + return s.desc +} + +func (s *summary) Observe(v float64) { + s.bufMtx.Lock() + defer s.bufMtx.Unlock() + + now := time.Now() + if now.After(s.hotBufExpTime) { + s.asyncFlush(now) + } + s.hotBuf = append(s.hotBuf, v) + if len(s.hotBuf) == cap(s.hotBuf) { + s.asyncFlush(now) + } +} + +func (s *summary) Write(out *dto.Metric) error { + sum := &dto.Summary{} + qs := make([]*dto.Quantile, 0, len(s.objectives)) + + s.bufMtx.Lock() + s.mtx.Lock() + // Swap bufs even if hotBuf is empty to set new hotBufExpTime. + s.swapBufs(time.Now()) + s.bufMtx.Unlock() + + s.flushColdBuf() + sum.SampleCount = proto.Uint64(s.cnt) + sum.SampleSum = proto.Float64(s.sum) + + for _, rank := range s.sortedObjectives { + var q float64 + if s.headStream.Count() == 0 { + q = math.NaN() + } else { + q = s.headStream.Query(rank) + } + qs = append(qs, &dto.Quantile{ + Quantile: proto.Float64(rank), + Value: proto.Float64(q), + }) + } + + s.mtx.Unlock() + + if len(qs) > 0 { + sort.Sort(quantSort(qs)) + } + sum.Quantile = qs + + out.Summary = sum + out.Label = s.labelPairs + return nil +} + +func (s *summary) newStream() *quantile.Stream { + return quantile.NewTargeted(s.objectives) +} + +// asyncFlush needs bufMtx locked. +func (s *summary) asyncFlush(now time.Time) { + s.mtx.Lock() + s.swapBufs(now) + + // Unblock the original goroutine that was responsible for the mutation + // that triggered the compaction. But hold onto the global non-buffer + // state mutex until the operation finishes. + go func() { + s.flushColdBuf() + s.mtx.Unlock() + }() +} + +// rotateStreams needs mtx AND bufMtx locked. +func (s *summary) maybeRotateStreams() { + for !s.hotBufExpTime.Equal(s.headStreamExpTime) { + s.headStream.Reset() + s.headStreamIdx++ + if s.headStreamIdx >= len(s.streams) { + s.headStreamIdx = 0 + } + s.headStream = s.streams[s.headStreamIdx] + s.headStreamExpTime = s.headStreamExpTime.Add(s.streamDuration) + } +} + +// flushColdBuf needs mtx locked. +func (s *summary) flushColdBuf() { + for _, v := range s.coldBuf { + for _, stream := range s.streams { + stream.Insert(v) + } + s.cnt++ + s.sum += v + } + s.coldBuf = s.coldBuf[0:0] + s.maybeRotateStreams() +} + +// swapBufs needs mtx AND bufMtx locked, coldBuf must be empty. +func (s *summary) swapBufs(now time.Time) { + if len(s.coldBuf) != 0 { + panic("coldBuf is not empty") + } + s.hotBuf, s.coldBuf = s.coldBuf, s.hotBuf + // hotBuf is now empty and gets new expiration set. + for now.After(s.hotBufExpTime) { + s.hotBufExpTime = s.hotBufExpTime.Add(s.streamDuration) + } +} + +type summaryCounts struct { + // sumBits contains the bits of the float64 representing the sum of all + // observations. sumBits and count have to go first in the struct to + // guarantee alignment for atomic operations. + // http://golang.org/pkg/sync/atomic/#pkg-note-BUG + sumBits uint64 + count uint64 +} + +type noObjectivesSummary struct { + // countAndHotIdx enables lock-free writes with use of atomic updates. + // The most significant bit is the hot index [0 or 1] of the count field + // below. Observe calls update the hot one. All remaining bits count the + // number of Observe calls. Observe starts by incrementing this counter, + // and finish by incrementing the count field in the respective + // summaryCounts, as a marker for completion. + // + // Calls of the Write method (which are non-mutating reads from the + // perspective of the summary) swap the hot–cold under the writeMtx + // lock. A cooldown is awaited (while locked) by comparing the number of + // observations with the initiation count. Once they match, then the + // last observation on the now cool one has completed. All cool fields must + // be merged into the new hot before releasing writeMtx. + + // Fields with atomic access first! See alignment constraint: + // http://golang.org/pkg/sync/atomic/#pkg-note-BUG + countAndHotIdx uint64 + + selfCollector + desc *Desc + writeMtx sync.Mutex // Only used in the Write method. + + // Two counts, one is "hot" for lock-free observations, the other is + // "cold" for writing out a dto.Metric. It has to be an array of + // pointers to guarantee 64bit alignment of the histogramCounts, see + // http://golang.org/pkg/sync/atomic/#pkg-note-BUG. + counts [2]*summaryCounts + + labelPairs []*dto.LabelPair +} + +func (s *noObjectivesSummary) Desc() *Desc { + return s.desc +} + +func (s *noObjectivesSummary) Observe(v float64) { + // We increment h.countAndHotIdx so that the counter in the lower + // 63 bits gets incremented. At the same time, we get the new value + // back, which we can use to find the currently-hot counts. + n := atomic.AddUint64(&s.countAndHotIdx, 1) + hotCounts := s.counts[n>>63] + + for { + oldBits := atomic.LoadUint64(&hotCounts.sumBits) + newBits := math.Float64bits(math.Float64frombits(oldBits) + v) + if atomic.CompareAndSwapUint64(&hotCounts.sumBits, oldBits, newBits) { + break + } + } + // Increment count last as we take it as a signal that the observation + // is complete. + atomic.AddUint64(&hotCounts.count, 1) +} + +func (s *noObjectivesSummary) Write(out *dto.Metric) error { + // For simplicity, we protect this whole method by a mutex. It is not in + // the hot path, i.e. Observe is called much more often than Write. The + // complication of making Write lock-free isn't worth it, if possible at + // all. + s.writeMtx.Lock() + defer s.writeMtx.Unlock() + + // Adding 1<<63 switches the hot index (from 0 to 1 or from 1 to 0) + // without touching the count bits. See the struct comments for a full + // description of the algorithm. + n := atomic.AddUint64(&s.countAndHotIdx, 1<<63) + // count is contained unchanged in the lower 63 bits. + count := n & ((1 << 63) - 1) + // The most significant bit tells us which counts is hot. The complement + // is thus the cold one. + hotCounts := s.counts[n>>63] + coldCounts := s.counts[(^n)>>63] + + // Await cooldown. + for count != atomic.LoadUint64(&coldCounts.count) { + runtime.Gosched() // Let observations get work done. + } + + sum := &dto.Summary{ + SampleCount: proto.Uint64(count), + SampleSum: proto.Float64(math.Float64frombits(atomic.LoadUint64(&coldCounts.sumBits))), + } + + out.Summary = sum + out.Label = s.labelPairs + + // Finally add all the cold counts to the new hot counts and reset the cold counts. + atomic.AddUint64(&hotCounts.count, count) + atomic.StoreUint64(&coldCounts.count, 0) + for { + oldBits := atomic.LoadUint64(&hotCounts.sumBits) + newBits := math.Float64bits(math.Float64frombits(oldBits) + sum.GetSampleSum()) + if atomic.CompareAndSwapUint64(&hotCounts.sumBits, oldBits, newBits) { + atomic.StoreUint64(&coldCounts.sumBits, 0) + break + } + } + return nil +} + +type quantSort []*dto.Quantile + +func (s quantSort) Len() int { + return len(s) +} + +func (s quantSort) Swap(i, j int) { + s[i], s[j] = s[j], s[i] +} + +func (s quantSort) Less(i, j int) bool { + return s[i].GetQuantile() < s[j].GetQuantile() +} + +// SummaryVec is a Collector that bundles a set of Summaries that all share the +// same Desc, but have different values for their variable labels. This is used +// if you want to count the same thing partitioned by various dimensions +// (e.g. HTTP request latencies, partitioned by status code and method). Create +// instances with NewSummaryVec. +type SummaryVec struct { + *metricVec +} + +// NewSummaryVec creates a new SummaryVec based on the provided SummaryOpts and +// partitioned by the given label names. +// +// Due to the way a Summary is represented in the Prometheus text format and how +// it is handled by the Prometheus server internally, “quantile” is an illegal +// label name. NewSummaryVec will panic if this label name is used. +func NewSummaryVec(opts SummaryOpts, labelNames []string) *SummaryVec { + for _, ln := range labelNames { + if ln == quantileLabel { + panic(errQuantileLabelNotAllowed) + } + } + desc := NewDesc( + BuildFQName(opts.Namespace, opts.Subsystem, opts.Name), + opts.Help, + labelNames, + opts.ConstLabels, + ) + return &SummaryVec{ + metricVec: newMetricVec(desc, func(lvs ...string) Metric { + return newSummary(desc, opts, lvs...) + }), + } +} + +// GetMetricWithLabelValues returns the Summary for the given slice of label +// values (same order as the VariableLabels in Desc). If that combination of +// label values is accessed for the first time, a new Summary is created. +// +// It is possible to call this method without using the returned Summary to only +// create the new Summary but leave it at its starting value, a Summary without +// any observations. +// +// Keeping the Summary for later use is possible (and should be considered if +// performance is critical), but keep in mind that Reset, DeleteLabelValues and +// Delete can be used to delete the Summary from the SummaryVec. In that case, +// the Summary will still exist, but it will not be exported anymore, even if a +// Summary with the same label values is created later. See also the CounterVec +// example. +// +// An error is returned if the number of label values is not the same as the +// number of VariableLabels in Desc (minus any curried labels). +// +// Note that for more than one label value, this method is prone to mistakes +// caused by an incorrect order of arguments. Consider GetMetricWith(Labels) as +// an alternative to avoid that type of mistake. For higher label numbers, the +// latter has a much more readable (albeit more verbose) syntax, but it comes +// with a performance overhead (for creating and processing the Labels map). +// See also the GaugeVec example. +func (v *SummaryVec) GetMetricWithLabelValues(lvs ...string) (Observer, error) { + metric, err := v.metricVec.getMetricWithLabelValues(lvs...) + if metric != nil { + return metric.(Observer), err + } + return nil, err +} + +// GetMetricWith returns the Summary for the given Labels map (the label names +// must match those of the VariableLabels in Desc). If that label map is +// accessed for the first time, a new Summary is created. Implications of +// creating a Summary without using it and keeping the Summary for later use are +// the same as for GetMetricWithLabelValues. +// +// An error is returned if the number and names of the Labels are inconsistent +// with those of the VariableLabels in Desc (minus any curried labels). +// +// This method is used for the same purpose as +// GetMetricWithLabelValues(...string). See there for pros and cons of the two +// methods. +func (v *SummaryVec) GetMetricWith(labels Labels) (Observer, error) { + metric, err := v.metricVec.getMetricWith(labels) + if metric != nil { + return metric.(Observer), err + } + return nil, err +} + +// WithLabelValues works as GetMetricWithLabelValues, but panics where +// GetMetricWithLabelValues would have returned an error. Not returning an +// error allows shortcuts like +// myVec.WithLabelValues("404", "GET").Observe(42.21) +func (v *SummaryVec) WithLabelValues(lvs ...string) Observer { + s, err := v.GetMetricWithLabelValues(lvs...) + if err != nil { + panic(err) + } + return s +} + +// With works as GetMetricWith, but panics where GetMetricWithLabels would have +// returned an error. Not returning an error allows shortcuts like +// myVec.With(prometheus.Labels{"code": "404", "method": "GET"}).Observe(42.21) +func (v *SummaryVec) With(labels Labels) Observer { + s, err := v.GetMetricWith(labels) + if err != nil { + panic(err) + } + return s +} + +// CurryWith returns a vector curried with the provided labels, i.e. the +// returned vector has those labels pre-set for all labeled operations performed +// on it. The cardinality of the curried vector is reduced accordingly. The +// order of the remaining labels stays the same (just with the curried labels +// taken out of the sequence – which is relevant for the +// (GetMetric)WithLabelValues methods). It is possible to curry a curried +// vector, but only with labels not yet used for currying before. +// +// The metrics contained in the SummaryVec are shared between the curried and +// uncurried vectors. They are just accessed differently. Curried and uncurried +// vectors behave identically in terms of collection. Only one must be +// registered with a given registry (usually the uncurried version). The Reset +// method deletes all metrics, even if called on a curried vector. +func (v *SummaryVec) CurryWith(labels Labels) (ObserverVec, error) { + vec, err := v.curryWith(labels) + if vec != nil { + return &SummaryVec{vec}, err + } + return nil, err +} + +// MustCurryWith works as CurryWith but panics where CurryWith would have +// returned an error. +func (v *SummaryVec) MustCurryWith(labels Labels) ObserverVec { + vec, err := v.CurryWith(labels) + if err != nil { + panic(err) + } + return vec +} + +type constSummary struct { + desc *Desc + count uint64 + sum float64 + quantiles map[float64]float64 + labelPairs []*dto.LabelPair +} + +func (s *constSummary) Desc() *Desc { + return s.desc +} + +func (s *constSummary) Write(out *dto.Metric) error { + sum := &dto.Summary{} + qs := make([]*dto.Quantile, 0, len(s.quantiles)) + + sum.SampleCount = proto.Uint64(s.count) + sum.SampleSum = proto.Float64(s.sum) + + for rank, q := range s.quantiles { + qs = append(qs, &dto.Quantile{ + Quantile: proto.Float64(rank), + Value: proto.Float64(q), + }) + } + + if len(qs) > 0 { + sort.Sort(quantSort(qs)) + } + sum.Quantile = qs + + out.Summary = sum + out.Label = s.labelPairs + + return nil +} + +// NewConstSummary returns a metric representing a Prometheus summary with fixed +// values for the count, sum, and quantiles. As those parameters cannot be +// changed, the returned value does not implement the Summary interface (but +// only the Metric interface). Users of this package will not have much use for +// it in regular operations. However, when implementing custom Collectors, it is +// useful as a throw-away metric that is generated on the fly to send it to +// Prometheus in the Collect method. +// +// quantiles maps ranks to quantile values. For example, a median latency of +// 0.23s and a 99th percentile latency of 0.56s would be expressed as: +// map[float64]float64{0.5: 0.23, 0.99: 0.56} +// +// NewConstSummary returns an error if the length of labelValues is not +// consistent with the variable labels in Desc or if Desc is invalid. +func NewConstSummary( + desc *Desc, + count uint64, + sum float64, + quantiles map[float64]float64, + labelValues ...string, +) (Metric, error) { + if desc.err != nil { + return nil, desc.err + } + if err := validateLabelValues(labelValues, len(desc.variableLabels)); err != nil { + return nil, err + } + return &constSummary{ + desc: desc, + count: count, + sum: sum, + quantiles: quantiles, + labelPairs: makeLabelPairs(desc, labelValues), + }, nil +} + +// MustNewConstSummary is a version of NewConstSummary that panics where +// NewConstMetric would have returned an error. +func MustNewConstSummary( + desc *Desc, + count uint64, + sum float64, + quantiles map[float64]float64, + labelValues ...string, +) Metric { + m, err := NewConstSummary(desc, count, sum, quantiles, labelValues...) + if err != nil { + panic(err) + } + return m +} diff --git a/vendor/github.com/prometheus/client_golang/prometheus/timer.go b/vendor/github.com/prometheus/client_golang/prometheus/timer.go new file mode 100644 index 000000000..8d5f10523 --- /dev/null +++ b/vendor/github.com/prometheus/client_golang/prometheus/timer.go @@ -0,0 +1,54 @@ +// Copyright 2016 The Prometheus Authors +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package prometheus + +import "time" + +// Timer is a helper type to time functions. Use NewTimer to create new +// instances. +type Timer struct { + begin time.Time + observer Observer +} + +// NewTimer creates a new Timer. The provided Observer is used to observe a +// duration in seconds. Timer is usually used to time a function call in the +// following way: +// func TimeMe() { +// timer := NewTimer(myHistogram) +// defer timer.ObserveDuration() +// // Do actual work. +// } +func NewTimer(o Observer) *Timer { + return &Timer{ + begin: time.Now(), + observer: o, + } +} + +// ObserveDuration records the duration passed since the Timer was created with +// NewTimer. It calls the Observe method of the Observer provided during +// construction with the duration in seconds as an argument. The observed +// duration is also returned. ObserveDuration is usually called with a defer +// statement. +// +// Note that this method is only guaranteed to never observe negative durations +// if used with Go1.9+. +func (t *Timer) ObserveDuration() time.Duration { + d := time.Since(t.begin) + if t.observer != nil { + t.observer.Observe(d.Seconds()) + } + return d +} diff --git a/vendor/github.com/prometheus/client_golang/prometheus/untyped.go b/vendor/github.com/prometheus/client_golang/prometheus/untyped.go new file mode 100644 index 000000000..0f9ce63f4 --- /dev/null +++ b/vendor/github.com/prometheus/client_golang/prometheus/untyped.go @@ -0,0 +1,42 @@ +// 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 prometheus + +// UntypedOpts is an alias for Opts. See there for doc comments. +type UntypedOpts Opts + +// UntypedFunc works like GaugeFunc but the collected metric is of type +// "Untyped". UntypedFunc is useful to mirror an external metric of unknown +// type. +// +// To create UntypedFunc instances, use NewUntypedFunc. +type UntypedFunc interface { + Metric + Collector +} + +// NewUntypedFunc creates a new UntypedFunc based on the provided +// UntypedOpts. The value reported is determined by calling the given function +// from within the Write method. Take into account that metric collection may +// happen concurrently. If that results in concurrent calls to Write, like in +// the case where an UntypedFunc is directly registered with Prometheus, the +// provided function must be concurrency-safe. +func NewUntypedFunc(opts UntypedOpts, function func() float64) UntypedFunc { + return newValueFunc(NewDesc( + BuildFQName(opts.Namespace, opts.Subsystem, opts.Name), + opts.Help, + nil, + opts.ConstLabels, + ), UntypedValue, function) +} diff --git a/vendor/github.com/prometheus/client_golang/prometheus/value.go b/vendor/github.com/prometheus/client_golang/prometheus/value.go new file mode 100644 index 000000000..eb248f108 --- /dev/null +++ b/vendor/github.com/prometheus/client_golang/prometheus/value.go @@ -0,0 +1,162 @@ +// 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 prometheus + +import ( + "fmt" + "sort" + + "github.com/golang/protobuf/proto" + + dto "github.com/prometheus/client_model/go" +) + +// ValueType is an enumeration of metric types that represent a simple value. +type ValueType int + +// Possible values for the ValueType enum. +const ( + _ ValueType = iota + CounterValue + GaugeValue + UntypedValue +) + +// valueFunc is a generic metric for simple values retrieved on collect time +// from a function. It implements Metric and Collector. Its effective type is +// determined by ValueType. This is a low-level building block used by the +// library to back the implementations of CounterFunc, GaugeFunc, and +// UntypedFunc. +type valueFunc struct { + selfCollector + + desc *Desc + valType ValueType + function func() float64 + labelPairs []*dto.LabelPair +} + +// newValueFunc returns a newly allocated valueFunc with the given Desc and +// ValueType. The value reported is determined by calling the given function +// from within the Write method. Take into account that metric collection may +// happen concurrently. If that results in concurrent calls to Write, like in +// the case where a valueFunc is directly registered with Prometheus, the +// provided function must be concurrency-safe. +func newValueFunc(desc *Desc, valueType ValueType, function func() float64) *valueFunc { + result := &valueFunc{ + desc: desc, + valType: valueType, + function: function, + labelPairs: makeLabelPairs(desc, nil), + } + result.init(result) + return result +} + +func (v *valueFunc) Desc() *Desc { + return v.desc +} + +func (v *valueFunc) Write(out *dto.Metric) error { + return populateMetric(v.valType, v.function(), v.labelPairs, out) +} + +// NewConstMetric returns a metric with one fixed value that cannot be +// changed. Users of this package will not have much use for it in regular +// operations. However, when implementing custom Collectors, it is useful as a +// throw-away metric that is generated on the fly to send it to Prometheus in +// the Collect method. NewConstMetric returns an error if the length of +// labelValues is not consistent with the variable labels in Desc or if Desc is +// invalid. +func NewConstMetric(desc *Desc, valueType ValueType, value float64, labelValues ...string) (Metric, error) { + if desc.err != nil { + return nil, desc.err + } + if err := validateLabelValues(labelValues, len(desc.variableLabels)); err != nil { + return nil, err + } + return &constMetric{ + desc: desc, + valType: valueType, + val: value, + labelPairs: makeLabelPairs(desc, labelValues), + }, nil +} + +// MustNewConstMetric is a version of NewConstMetric that panics where +// NewConstMetric would have returned an error. +func MustNewConstMetric(desc *Desc, valueType ValueType, value float64, labelValues ...string) Metric { + m, err := NewConstMetric(desc, valueType, value, labelValues...) + if err != nil { + panic(err) + } + return m +} + +type constMetric struct { + desc *Desc + valType ValueType + val float64 + labelPairs []*dto.LabelPair +} + +func (m *constMetric) Desc() *Desc { + return m.desc +} + +func (m *constMetric) Write(out *dto.Metric) error { + return populateMetric(m.valType, m.val, m.labelPairs, out) +} + +func populateMetric( + t ValueType, + v float64, + labelPairs []*dto.LabelPair, + m *dto.Metric, +) error { + m.Label = labelPairs + switch t { + case CounterValue: + m.Counter = &dto.Counter{Value: proto.Float64(v)} + case GaugeValue: + m.Gauge = &dto.Gauge{Value: proto.Float64(v)} + case UntypedValue: + m.Untyped = &dto.Untyped{Value: proto.Float64(v)} + default: + return fmt.Errorf("encountered unknown type %v", t) + } + return nil +} + +func makeLabelPairs(desc *Desc, labelValues []string) []*dto.LabelPair { + totalLen := len(desc.variableLabels) + len(desc.constLabelPairs) + if totalLen == 0 { + // Super fast path. + return nil + } + if len(desc.variableLabels) == 0 { + // Moderately fast path. + return desc.constLabelPairs + } + labelPairs := make([]*dto.LabelPair, 0, totalLen) + for i, n := range desc.variableLabels { + labelPairs = append(labelPairs, &dto.LabelPair{ + Name: proto.String(n), + Value: proto.String(labelValues[i]), + }) + } + labelPairs = append(labelPairs, desc.constLabelPairs...) + sort.Sort(labelPairSorter(labelPairs)) + return labelPairs +} diff --git a/vendor/github.com/prometheus/client_golang/prometheus/vec.go b/vendor/github.com/prometheus/client_golang/prometheus/vec.go new file mode 100644 index 000000000..14ed9e856 --- /dev/null +++ b/vendor/github.com/prometheus/client_golang/prometheus/vec.go @@ -0,0 +1,472 @@ +// 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 prometheus + +import ( + "fmt" + "sync" + + "github.com/prometheus/common/model" +) + +// metricVec is a Collector to bundle metrics of the same name that differ in +// their label values. metricVec is not used directly (and therefore +// unexported). It is used as a building block for implementations of vectors of +// a given metric type, like GaugeVec, CounterVec, SummaryVec, and HistogramVec. +// It also handles label currying. It uses basicMetricVec internally. +type metricVec struct { + *metricMap + + curry []curriedLabelValue + + // hashAdd and hashAddByte can be replaced for testing collision handling. + hashAdd func(h uint64, s string) uint64 + hashAddByte func(h uint64, b byte) uint64 +} + +// newMetricVec returns an initialized metricVec. +func newMetricVec(desc *Desc, newMetric func(lvs ...string) Metric) *metricVec { + return &metricVec{ + metricMap: &metricMap{ + metrics: map[uint64][]metricWithLabelValues{}, + desc: desc, + newMetric: newMetric, + }, + hashAdd: hashAdd, + hashAddByte: hashAddByte, + } +} + +// DeleteLabelValues removes the metric where the variable labels are the same +// as those passed in as labels (same order as the VariableLabels in Desc). It +// returns true if a metric was deleted. +// +// It is not an error if the number of label values is not the same as the +// number of VariableLabels in Desc. However, such inconsistent label count can +// never match an actual metric, so the method will always return false in that +// case. +// +// Note that for more than one label value, this method is prone to mistakes +// caused by an incorrect order of arguments. Consider Delete(Labels) as an +// alternative to avoid that type of mistake. For higher label numbers, the +// latter has a much more readable (albeit more verbose) syntax, but it comes +// with a performance overhead (for creating and processing the Labels map). +// See also the CounterVec example. +func (m *metricVec) DeleteLabelValues(lvs ...string) bool { + h, err := m.hashLabelValues(lvs) + if err != nil { + return false + } + + return m.metricMap.deleteByHashWithLabelValues(h, lvs, m.curry) +} + +// Delete deletes the metric where the variable labels are the same as those +// passed in as labels. It returns true if a metric was deleted. +// +// It is not an error if the number and names of the Labels are inconsistent +// with those of the VariableLabels in Desc. However, such inconsistent Labels +// can never match an actual metric, so the method will always return false in +// that case. +// +// This method is used for the same purpose as DeleteLabelValues(...string). See +// there for pros and cons of the two methods. +func (m *metricVec) Delete(labels Labels) bool { + h, err := m.hashLabels(labels) + if err != nil { + return false + } + + return m.metricMap.deleteByHashWithLabels(h, labels, m.curry) +} + +func (m *metricVec) curryWith(labels Labels) (*metricVec, error) { + var ( + newCurry []curriedLabelValue + oldCurry = m.curry + iCurry int + ) + for i, label := range m.desc.variableLabels { + val, ok := labels[label] + if iCurry < len(oldCurry) && oldCurry[iCurry].index == i { + if ok { + return nil, fmt.Errorf("label name %q is already curried", label) + } + newCurry = append(newCurry, oldCurry[iCurry]) + iCurry++ + } else { + if !ok { + continue // Label stays uncurried. + } + newCurry = append(newCurry, curriedLabelValue{i, val}) + } + } + if l := len(oldCurry) + len(labels) - len(newCurry); l > 0 { + return nil, fmt.Errorf("%d unknown label(s) found during currying", l) + } + + return &metricVec{ + metricMap: m.metricMap, + curry: newCurry, + hashAdd: m.hashAdd, + hashAddByte: m.hashAddByte, + }, nil +} + +func (m *metricVec) getMetricWithLabelValues(lvs ...string) (Metric, error) { + h, err := m.hashLabelValues(lvs) + if err != nil { + return nil, err + } + + return m.metricMap.getOrCreateMetricWithLabelValues(h, lvs, m.curry), nil +} + +func (m *metricVec) getMetricWith(labels Labels) (Metric, error) { + h, err := m.hashLabels(labels) + if err != nil { + return nil, err + } + + return m.metricMap.getOrCreateMetricWithLabels(h, labels, m.curry), nil +} + +func (m *metricVec) hashLabelValues(vals []string) (uint64, error) { + if err := validateLabelValues(vals, len(m.desc.variableLabels)-len(m.curry)); err != nil { + return 0, err + } + + var ( + h = hashNew() + curry = m.curry + iVals, iCurry int + ) + for i := 0; i < len(m.desc.variableLabels); i++ { + if iCurry < len(curry) && curry[iCurry].index == i { + h = m.hashAdd(h, curry[iCurry].value) + iCurry++ + } else { + h = m.hashAdd(h, vals[iVals]) + iVals++ + } + h = m.hashAddByte(h, model.SeparatorByte) + } + return h, nil +} + +func (m *metricVec) hashLabels(labels Labels) (uint64, error) { + if err := validateValuesInLabels(labels, len(m.desc.variableLabels)-len(m.curry)); err != nil { + return 0, err + } + + var ( + h = hashNew() + curry = m.curry + iCurry int + ) + for i, label := range m.desc.variableLabels { + val, ok := labels[label] + if iCurry < len(curry) && curry[iCurry].index == i { + if ok { + return 0, fmt.Errorf("label name %q is already curried", label) + } + h = m.hashAdd(h, curry[iCurry].value) + iCurry++ + } else { + if !ok { + return 0, fmt.Errorf("label name %q missing in label map", label) + } + h = m.hashAdd(h, val) + } + h = m.hashAddByte(h, model.SeparatorByte) + } + return h, nil +} + +// metricWithLabelValues provides the metric and its label values for +// disambiguation on hash collision. +type metricWithLabelValues struct { + values []string + metric Metric +} + +// curriedLabelValue sets the curried value for a label at the given index. +type curriedLabelValue struct { + index int + value string +} + +// metricMap is a helper for metricVec and shared between differently curried +// metricVecs. +type metricMap struct { + mtx sync.RWMutex // Protects metrics. + metrics map[uint64][]metricWithLabelValues + desc *Desc + newMetric func(labelValues ...string) Metric +} + +// Describe implements Collector. It will send exactly one Desc to the provided +// channel. +func (m *metricMap) Describe(ch chan<- *Desc) { + ch <- m.desc +} + +// Collect implements Collector. +func (m *metricMap) Collect(ch chan<- Metric) { + m.mtx.RLock() + defer m.mtx.RUnlock() + + for _, metrics := range m.metrics { + for _, metric := range metrics { + ch <- metric.metric + } + } +} + +// Reset deletes all metrics in this vector. +func (m *metricMap) Reset() { + m.mtx.Lock() + defer m.mtx.Unlock() + + for h := range m.metrics { + delete(m.metrics, h) + } +} + +// 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 *metricMap) deleteByHashWithLabelValues( + h uint64, lvs []string, curry []curriedLabelValue, +) bool { + m.mtx.Lock() + defer m.mtx.Unlock() + + metrics, ok := m.metrics[h] + if !ok { + return false + } + + i := findMetricWithLabelValues(metrics, lvs, curry) + if i >= len(metrics) { + return false + } + + if len(metrics) > 1 { + m.metrics[h] = append(metrics[:i], metrics[i+1:]...) + } else { + delete(m.metrics, 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 *metricMap) deleteByHashWithLabels( + h uint64, labels Labels, curry []curriedLabelValue, +) bool { + m.mtx.Lock() + defer m.mtx.Unlock() + + metrics, ok := m.metrics[h] + if !ok { + return false + } + i := findMetricWithLabels(m.desc, metrics, labels, curry) + if i >= len(metrics) { + return false + } + + if len(metrics) > 1 { + m.metrics[h] = append(metrics[:i], metrics[i+1:]...) + } else { + delete(m.metrics, h) + } + return true +} + +// getOrCreateMetricWithLabelValues retrieves the metric by hash and label value +// or creates it and returns the new one. +// +// This function holds the mutex. +func (m *metricMap) getOrCreateMetricWithLabelValues( + hash uint64, lvs []string, curry []curriedLabelValue, +) Metric { + m.mtx.RLock() + metric, ok := m.getMetricWithHashAndLabelValues(hash, lvs, curry) + m.mtx.RUnlock() + if ok { + return metric + } + + m.mtx.Lock() + defer m.mtx.Unlock() + metric, ok = m.getMetricWithHashAndLabelValues(hash, lvs, curry) + if !ok { + inlinedLVs := inlineLabelValues(lvs, curry) + metric = m.newMetric(inlinedLVs...) + m.metrics[hash] = append(m.metrics[hash], metricWithLabelValues{values: inlinedLVs, metric: 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 *metricMap) getOrCreateMetricWithLabels( + hash uint64, labels Labels, curry []curriedLabelValue, +) Metric { + m.mtx.RLock() + metric, ok := m.getMetricWithHashAndLabels(hash, labels, curry) + m.mtx.RUnlock() + if ok { + return metric + } + + m.mtx.Lock() + defer m.mtx.Unlock() + metric, ok = m.getMetricWithHashAndLabels(hash, labels, curry) + if !ok { + lvs := extractLabelValues(m.desc, labels, curry) + metric = m.newMetric(lvs...) + m.metrics[hash] = append(m.metrics[hash], metricWithLabelValues{values: lvs, metric: metric}) + } + return metric +} + +// getMetricWithHashAndLabelValues gets a metric while handling possible +// collisions in the hash space. Must be called while holding the read mutex. +func (m *metricMap) getMetricWithHashAndLabelValues( + h uint64, lvs []string, curry []curriedLabelValue, +) (Metric, bool) { + metrics, ok := m.metrics[h] + if ok { + if i := findMetricWithLabelValues(metrics, lvs, curry); i < len(metrics) { + return metrics[i].metric, true + } + } + return nil, false +} + +// getMetricWithHashAndLabels gets a metric while handling possible collisions in +// the hash space. Must be called while holding read mutex. +func (m *metricMap) getMetricWithHashAndLabels( + h uint64, labels Labels, curry []curriedLabelValue, +) (Metric, bool) { + metrics, ok := m.metrics[h] + if ok { + if i := findMetricWithLabels(m.desc, metrics, labels, curry); 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 findMetricWithLabelValues( + metrics []metricWithLabelValues, lvs []string, curry []curriedLabelValue, +) int { + for i, metric := range metrics { + if matchLabelValues(metric.values, lvs, curry) { + return i + } + } + return len(metrics) +} + +// findMetricWithLabels returns the index of the matching metric or len(metrics) +// if not found. +func findMetricWithLabels( + desc *Desc, metrics []metricWithLabelValues, labels Labels, curry []curriedLabelValue, +) int { + for i, metric := range metrics { + if matchLabels(desc, metric.values, labels, curry) { + return i + } + } + return len(metrics) +} + +func matchLabelValues(values []string, lvs []string, curry []curriedLabelValue) bool { + if len(values) != len(lvs)+len(curry) { + return false + } + var iLVs, iCurry int + for i, v := range values { + if iCurry < len(curry) && curry[iCurry].index == i { + if v != curry[iCurry].value { + return false + } + iCurry++ + continue + } + if v != lvs[iLVs] { + return false + } + iLVs++ + } + return true +} + +func matchLabels(desc *Desc, values []string, labels Labels, curry []curriedLabelValue) bool { + if len(values) != len(labels)+len(curry) { + return false + } + iCurry := 0 + for i, k := range desc.variableLabels { + if iCurry < len(curry) && curry[iCurry].index == i { + if values[i] != curry[iCurry].value { + return false + } + iCurry++ + continue + } + if values[i] != labels[k] { + return false + } + } + return true +} + +func extractLabelValues(desc *Desc, labels Labels, curry []curriedLabelValue) []string { + labelValues := make([]string, len(labels)+len(curry)) + iCurry := 0 + for i, k := range desc.variableLabels { + if iCurry < len(curry) && curry[iCurry].index == i { + labelValues[i] = curry[iCurry].value + iCurry++ + continue + } + labelValues[i] = labels[k] + } + return labelValues +} + +func inlineLabelValues(lvs []string, curry []curriedLabelValue) []string { + labelValues := make([]string, len(lvs)+len(curry)) + var iCurry, iLVs int + for i := range labelValues { + if iCurry < len(curry) && curry[iCurry].index == i { + labelValues[i] = curry[iCurry].value + iCurry++ + continue + } + labelValues[i] = lvs[iLVs] + iLVs++ + } + return labelValues +} diff --git a/vendor/github.com/prometheus/client_golang/prometheus/wrap.go b/vendor/github.com/prometheus/client_golang/prometheus/wrap.go new file mode 100644 index 000000000..e303eef6d --- /dev/null +++ b/vendor/github.com/prometheus/client_golang/prometheus/wrap.go @@ -0,0 +1,200 @@ +// Copyright 2018 The Prometheus Authors +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package prometheus + +import ( + "fmt" + "sort" + + "github.com/golang/protobuf/proto" + + dto "github.com/prometheus/client_model/go" +) + +// WrapRegistererWith returns a Registerer wrapping the provided +// Registerer. Collectors registered with the returned Registerer will be +// registered with the wrapped Registerer in a modified way. The modified +// Collector adds the provided Labels to all Metrics it collects (as +// ConstLabels). The Metrics collected by the unmodified Collector must not +// duplicate any of those labels. +// +// WrapRegistererWith provides a way to add fixed labels to a subset of +// Collectors. It should not be used to add fixed labels to all metrics exposed. +// +// Conflicts between Collectors registered through the original Registerer with +// Collectors registered through the wrapping Registerer will still be +// detected. Any AlreadyRegisteredError returned by the Register method of +// either Registerer will contain the ExistingCollector in the form it was +// provided to the respective registry. +// +// The Collector example demonstrates a use of WrapRegistererWith. +func WrapRegistererWith(labels Labels, reg Registerer) Registerer { + return &wrappingRegisterer{ + wrappedRegisterer: reg, + labels: labels, + } +} + +// WrapRegistererWithPrefix returns a Registerer wrapping the provided +// Registerer. Collectors registered with the returned Registerer will be +// registered with the wrapped Registerer in a modified way. The modified +// Collector adds the provided prefix to the name of all Metrics it collects. +// +// WrapRegistererWithPrefix is useful to have one place to prefix all metrics of +// a sub-system. To make this work, register metrics of the sub-system with the +// wrapping Registerer returned by WrapRegistererWithPrefix. It is rarely useful +// to use the same prefix for all metrics exposed. In particular, do not prefix +// metric names that are standardized across applications, as that would break +// horizontal monitoring, for example the metrics provided by the Go collector +// (see NewGoCollector) and the process collector (see NewProcessCollector). (In +// fact, those metrics are already prefixed with “go_” or “process_”, +// respectively.) +// +// Conflicts between Collectors registered through the original Registerer with +// Collectors registered through the wrapping Registerer will still be +// detected. Any AlreadyRegisteredError returned by the Register method of +// either Registerer will contain the ExistingCollector in the form it was +// provided to the respective registry. +func WrapRegistererWithPrefix(prefix string, reg Registerer) Registerer { + return &wrappingRegisterer{ + wrappedRegisterer: reg, + prefix: prefix, + } +} + +type wrappingRegisterer struct { + wrappedRegisterer Registerer + prefix string + labels Labels +} + +func (r *wrappingRegisterer) Register(c Collector) error { + return r.wrappedRegisterer.Register(&wrappingCollector{ + wrappedCollector: c, + prefix: r.prefix, + labels: r.labels, + }) +} + +func (r *wrappingRegisterer) MustRegister(cs ...Collector) { + for _, c := range cs { + if err := r.Register(c); err != nil { + panic(err) + } + } +} + +func (r *wrappingRegisterer) Unregister(c Collector) bool { + return r.wrappedRegisterer.Unregister(&wrappingCollector{ + wrappedCollector: c, + prefix: r.prefix, + labels: r.labels, + }) +} + +type wrappingCollector struct { + wrappedCollector Collector + prefix string + labels Labels +} + +func (c *wrappingCollector) Collect(ch chan<- Metric) { + wrappedCh := make(chan Metric) + go func() { + c.wrappedCollector.Collect(wrappedCh) + close(wrappedCh) + }() + for m := range wrappedCh { + ch <- &wrappingMetric{ + wrappedMetric: m, + prefix: c.prefix, + labels: c.labels, + } + } +} + +func (c *wrappingCollector) Describe(ch chan<- *Desc) { + wrappedCh := make(chan *Desc) + go func() { + c.wrappedCollector.Describe(wrappedCh) + close(wrappedCh) + }() + for desc := range wrappedCh { + ch <- wrapDesc(desc, c.prefix, c.labels) + } +} + +func (c *wrappingCollector) unwrapRecursively() Collector { + switch wc := c.wrappedCollector.(type) { + case *wrappingCollector: + return wc.unwrapRecursively() + default: + return wc + } +} + +type wrappingMetric struct { + wrappedMetric Metric + prefix string + labels Labels +} + +func (m *wrappingMetric) Desc() *Desc { + return wrapDesc(m.wrappedMetric.Desc(), m.prefix, m.labels) +} + +func (m *wrappingMetric) Write(out *dto.Metric) error { + if err := m.wrappedMetric.Write(out); err != nil { + return err + } + if len(m.labels) == 0 { + // No wrapping labels. + return nil + } + for ln, lv := range m.labels { + out.Label = append(out.Label, &dto.LabelPair{ + Name: proto.String(ln), + Value: proto.String(lv), + }) + } + sort.Sort(labelPairSorter(out.Label)) + return nil +} + +func wrapDesc(desc *Desc, prefix string, labels Labels) *Desc { + constLabels := Labels{} + for _, lp := range desc.constLabelPairs { + constLabels[*lp.Name] = *lp.Value + } + for ln, lv := range labels { + if _, alreadyUsed := constLabels[ln]; alreadyUsed { + return &Desc{ + fqName: desc.fqName, + help: desc.help, + variableLabels: desc.variableLabels, + constLabelPairs: desc.constLabelPairs, + err: fmt.Errorf("attempted wrapping with already existing label name %q", ln), + } + } + constLabels[ln] = lv + } + // NewDesc will do remaining validations. + newDesc := NewDesc(prefix+desc.fqName, desc.help, desc.variableLabels, constLabels) + // Propagate errors if there was any. This will override any errer + // created by NewDesc above, i.e. earlier errors get precedence. + if desc.err != nil { + newDesc.err = desc.err + } + return newDesc +} |