1
0
mirror of https://github.com/rancher/norman.git synced 2025-09-03 16:25:09 +00:00

Switch to go modules

This commit is contained in:
Darren Shepherd
2019-08-19 10:03:03 -07:00
parent 07c964e242
commit 40212fa263
5606 changed files with 263147 additions and 766229 deletions

View File

@@ -1,26 +0,0 @@
# Compiled Object files, Static and Dynamic libs (Shared Objects)
*.o
*.a
*.so
# Folders
_obj
_test
# Architecture specific extensions/prefixes
*.[568vq]
[568vq].out
*.cgo1.go
*.cgo2.c
_cgo_defun.c
_cgo_gotypes.go
_cgo_export.*
_testmain.go
*.exe
*~
*#
.build

View File

@@ -1,10 +0,0 @@
sudo: false
language: go
go:
- 1.6.3
- 1.7
- 1.8.1
script:
- go test -short ./...

View File

@@ -1,109 +0,0 @@
## 0.8.0 / 2016-08-17
* [CHANGE] Registry is doing more consistency checks. This might break
existing setups that used to export inconsistent metrics.
* [CHANGE] Pushing to Pushgateway moved to package `push` and changed to allow
arbitrary grouping.
* [CHANGE] Removed `SelfCollector`.
* [CHANGE] Removed `PanicOnCollectError` and `EnableCollectChecks` methods.
* [CHANGE] Moved packages to the prometheus/common repo: `text`, `model`,
`extraction`.
* [CHANGE] Deprecated a number of functions.
* [FEATURE] Allow custom registries. Added `Registerer` and `Gatherer`
interfaces.
* [FEATURE] Separated HTTP exposition, allowing custom HTTP handlers (package
`promhttp`) and enabling the creation of other exposition mechanisms.
* [FEATURE] `MustRegister` is variadic now, allowing registration of many
collectors in one call.
* [FEATURE] Added HTTP API v1 package.
* [ENHANCEMENT] Numerous documentation improvements.
* [ENHANCEMENT] Improved metric sorting.
* [ENHANCEMENT] Inlined fnv64a hashing for improved performance.
* [ENHANCEMENT] Several test improvements.
* [BUGFIX] Handle collisions in MetricVec.
## 0.7.0 / 2015-07-27
* [CHANGE] Rename ExporterLabelPrefix to ExportedLabelPrefix.
* [BUGFIX] Closed gaps in metric consistency check.
* [BUGFIX] Validate LabelName/LabelSet on JSON unmarshaling.
* [ENHANCEMENT] Document the possibility to create "empty" metrics in
a metric vector.
* [ENHANCEMENT] Fix and clarify various doc comments and the README.md.
* [ENHANCEMENT] (Kind of) solve "The Proxy Problem" of http.InstrumentHandler.
* [ENHANCEMENT] Change responseWriterDelegator.written to int64.
## 0.6.0 / 2015-06-01
* [CHANGE] Rename process_goroutines to go_goroutines.
* [ENHANCEMENT] Validate label names during YAML decoding.
* [ENHANCEMENT] Add LabelName regular expression.
* [BUGFIX] Ensure alignment of struct members for 32-bit systems.
## 0.5.0 / 2015-05-06
* [BUGFIX] Removed a weakness in the fingerprinting aka signature code.
This makes fingerprinting slower and more allocation-heavy, but the
weakness was too severe to be tolerated.
* [CHANGE] As a result of the above, Metric.Fingerprint is now returning
a different fingerprint. To keep the same fingerprint, the new method
Metric.FastFingerprint was introduced, which will be used by the
Prometheus server for storage purposes (implying that a collision
detection has to be added, too).
* [ENHANCEMENT] The Metric.Equal and Metric.Before do not depend on
fingerprinting anymore, removing the possibility of an undetected
fingerprint collision.
* [FEATURE] The Go collector in the exposition library includes garbage
collection stats.
* [FEATURE] The exposition library allows to create constant "throw-away"
summaries and histograms.
* [CHANGE] A number of new reserved labels and prefixes.
## 0.4.0 / 2015-04-08
* [CHANGE] Return NaN when Summaries have no observations yet.
* [BUGFIX] Properly handle Summary decay upon Write().
* [BUGFIX] Fix the documentation link to the consumption library.
* [FEATURE] Allow the metric family injection hook to merge with existing
metric families.
* [ENHANCEMENT] Removed cgo dependency and conditional compilation of procfs.
* [MAINTENANCE] Adjusted to changes in matttproud/golang_protobuf_extensions.
## 0.3.2 / 2015-03-11
* [BUGFIX] Fixed the receiver type of COWMetric.Set(). This method is
only used by the Prometheus server internally.
* [CLEANUP] Added licenses of vendored code left out by godep.
## 0.3.1 / 2015-03-04
* [ENHANCEMENT] Switched fingerprinting functions from own free list to
sync.Pool.
* [CHANGE] Makefile uses Go 1.4.2 now (only relevant for examples and tests).
## 0.3.0 / 2015-03-03
* [CHANGE] Changed the fingerprinting for metrics. THIS WILL INVALIDATE ALL
PERSISTED FINGERPRINTS. IF YOU COMPILE THE PROMETHEUS SERVER WITH THIS
VERSION, YOU HAVE TO WIPE THE PREVIOUSLY CREATED STORAGE.
* [CHANGE] LabelValuesToSignature removed. (Nobody had used it, and it was
arguably broken.)
* [CHANGE] Vendored dependencies. Those are only used by the Makefile. If
client_golang is used as a library, the vendoring will stay out of your way.
* [BUGFIX] Remove a weakness in the fingerprinting for metrics. (This made
the fingerprinting change above necessary.)
* [FEATURE] Added new fingerprinting functions SignatureForLabels and
SignatureWithoutLabels to be used by the Prometheus server. These functions
require fewer allocations than the ones currently used by the server.
## 0.2.0 / 2015-02-23
* [FEATURE] Introduce new Histagram metric type.
* [CHANGE] Ignore process collector errors for now (better error handling
pending).
* [CHANGE] Use clear error interface for process pidFn.
* [BUGFIX] Fix Go download links for several archs and OSes.
* [ENHANCEMENT] Massively improve Gauge and Counter performance.
* [ENHANCEMENT] Catch illegal label names for summaries in histograms.
* [ENHANCEMENT] Reduce allocations during fingerprinting.
* [ENHANCEMENT] Remove cgo dependency. procfs package will only be included if
both cgo is available and the build is for an OS with procfs.
* [CLEANUP] Clean up code style issues.
* [CLEANUP] Mark slow test as such and exclude them from travis.
* [CLEANUP] Update protobuf library package name.
* [CLEANUP] Updated vendoring of beorn7/perks.
## 0.1.0 / 2015-02-02
* [CLEANUP] Introduced semantic versioning and changelog. From now on,
changes will be reported in this file.

View File

@@ -1,18 +0,0 @@
# Contributing
Prometheus uses GitHub to manage reviews of pull requests.
* If you have a trivial fix or improvement, go ahead and create a pull request,
addressing (with `@...`) the maintainer of this repository (see
[MAINTAINERS.md](MAINTAINERS.md)) in the description of the pull request.
* If you plan to do something more involved, first discuss your ideas
on our [mailing list](https://groups.google.com/forum/?fromgroups#!forum/prometheus-developers).
This will avoid unnecessary work and surely give you and us a good deal
of inspiration.
* Relevant coding style guidelines are the [Go Code Review
Comments](https://code.google.com/p/go-wiki/wiki/CodeReviewComments)
and the _Formatting and style_ section of Peter Bourgon's [Go: Best
Practices for Production
Environments](http://peter.bourgon.org/go-in-production/#formatting-and-style).

View File

@@ -1 +0,0 @@
* Björn Rabenstein <beorn@soundcloud.com>

View File

@@ -1,47 +0,0 @@
# Prometheus Go client library
[![Build Status](https://travis-ci.org/prometheus/client_golang.svg?branch=master)](https://travis-ci.org/prometheus/client_golang)
[![Go Report Card](https://goreportcard.com/badge/github.com/prometheus/client_golang)](https://goreportcard.com/report/github.com/prometheus/client_golang)
This is the [Go](http://golang.org) client library for
[Prometheus](http://prometheus.io). It has two separate parts, one for
instrumenting application code, and one for creating clients that talk to the
Prometheus HTTP API.
## Instrumenting applications
[![code-coverage](http://gocover.io/_badge/github.com/prometheus/client_golang/prometheus)](http://gocover.io/github.com/prometheus/client_golang/prometheus) [![go-doc](https://godoc.org/github.com/prometheus/client_golang/prometheus?status.svg)](https://godoc.org/github.com/prometheus/client_golang/prometheus)
The
[`prometheus` directory](https://github.com/prometheus/client_golang/tree/master/prometheus)
contains the instrumentation library. See the
[best practices section](http://prometheus.io/docs/practices/naming/) of the
Prometheus documentation to learn more about instrumenting applications.
The
[`examples` directory](https://github.com/prometheus/client_golang/tree/master/examples)
contains simple examples of instrumented code.
## Client for the Prometheus HTTP API
[![code-coverage](http://gocover.io/_badge/github.com/prometheus/client_golang/api/prometheus)](http://gocover.io/github.com/prometheus/client_golang/api/prometheus) [![go-doc](https://godoc.org/github.com/prometheus/client_golang/api/prometheus?status.svg)](https://godoc.org/github.com/prometheus/client_golang/api/prometheus)
The
[`api/prometheus` directory](https://github.com/prometheus/client_golang/tree/master/api/prometheus)
contains the client for the
[Prometheus HTTP API](http://prometheus.io/docs/querying/api/). It allows you
to write Go applications that query time series data from a Prometheus
server. It is still in alpha stage.
## Where is `model`, `extraction`, and `text`?
The `model` packages has been moved to
[`prometheus/common/model`](https://github.com/prometheus/common/tree/master/model).
The `extraction` and `text` packages are now contained in
[`prometheus/common/expfmt`](https://github.com/prometheus/common/tree/master/expfmt).
## Contributing and community
See the [contributing guidelines](CONTRIBUTING.md) and the
[Community section](http://prometheus.io/community/) of the homepage.

View File

@@ -1 +0,0 @@
0.8.0

View File

@@ -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
}

View File

@@ -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"
}

View File

@@ -29,27 +29,72 @@ type Collector interface {
// collected by this Collector to the provided channel and returns once
// the last descriptor has been sent. The sent descriptors fulfill the
// consistency and uniqueness requirements described in the Desc
// documentation. (It is valid if one and the same Collector sends
// duplicate descriptors. Those duplicates are simply ignored. However,
// two different Collectors must not send duplicate descriptors.) This
// method idempotently sends the same descriptors throughout the
// lifetime of the Collector. If a Collector encounters an error while
// executing this method, it must send an invalid descriptor (created
// with NewInvalidDesc) to signal the error to the registry.
// 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. 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.
// 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.

View File

@@ -15,6 +15,10 @@ 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
@@ -42,6 +46,14 @@ type Counter interface {
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),
@@ -49,20 +61,58 @@ func NewCounter(opts CounterOpts) Counter {
nil,
opts.ConstLabels,
)
result := &counter{value: value{desc: desc, valType: CounterValue, labelPairs: desc.constLabelPairs}}
result := &counter{desc: desc, labelPairs: desc.constLabelPairs}
result.init(result) // Init self-collection.
return result
}
type counter struct {
value
// 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"))
}
c.value.Add(v)
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
@@ -70,16 +120,12 @@ func (c *counter) Add(v float64) {
// 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.
//
// CounterVec embeds MetricVec. See there for a full list of methods with
// detailed documentation.
type CounterVec struct {
*MetricVec
*metricVec
}
// NewCounterVec creates a new CounterVec based on the provided CounterOpts and
// partitioned by the given label names. At least one label name must be
// provided.
// partitioned by the given label names.
func NewCounterVec(opts CounterOpts, labelNames []string) *CounterVec {
desc := NewDesc(
BuildFQName(opts.Namespace, opts.Subsystem, opts.Name),
@@ -88,34 +134,62 @@ func NewCounterVec(opts CounterOpts, labelNames []string) *CounterVec {
opts.ConstLabels,
)
return &CounterVec{
MetricVec: newMetricVec(desc, func(lvs ...string) Metric {
result := &counter{value: value{
desc: desc,
valType: CounterValue,
labelPairs: makeLabelPairs(desc, lvs),
}}
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 replaces the method of the same name in
// MetricVec. The difference is that this method returns a Counter and not a
// Metric so that no type conversion is required.
func (m *CounterVec) GetMetricWithLabelValues(lvs ...string) (Counter, error) {
metric, err := m.MetricVec.GetMetricWithLabelValues(lvs...)
// 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 replaces the method of the same name in MetricVec. The
// difference is that this method returns a Counter and not a Metric so that no
// type conversion is required.
func (m *CounterVec) GetMetricWith(labels Labels) (Counter, error) {
metric, err := m.MetricVec.GetMetricWith(labels)
// 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
}
@@ -123,18 +197,57 @@ func (m *CounterVec) GetMetricWith(labels Labels) (Counter, error) {
}
// WithLabelValues works as GetMetricWithLabelValues, but panics where
// GetMetricWithLabelValues would have returned an error. By not returning an
// error, WithLabelValues allows shortcuts like
// GetMetricWithLabelValues would have returned an error. Not returning an
// error allows shortcuts like
// myVec.WithLabelValues("404", "GET").Add(42)
func (m *CounterVec) WithLabelValues(lvs ...string) Counter {
return m.MetricVec.WithLabelValues(lvs...).(Counter)
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. By not returning an error, With allows shortcuts like
// myVec.With(Labels{"code": "404", "method": "GET"}).Add(42)
func (m *CounterVec) With(labels Labels) Counter {
return m.MetricVec.With(labels).(Counter)
// 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

View File

@@ -25,19 +25,6 @@ import (
dto "github.com/prometheus/client_model/go"
)
// reservedLabelPrefix is a prefix which is not legal in user-supplied
// label names.
const reservedLabelPrefix = "__"
// Labels represents a collection of label name -> value mappings. This type is
// commonly used with the With(Labels) and GetMetricWith(Labels) methods of
// metric vector Collectors, e.g.:
// 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
// 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
@@ -80,24 +67,19 @@ type Desc struct {
// NewDesc allocates and initializes a new Desc. Errors are recorded in the Desc
// and will be reported on registration time. variableLabels and constLabels can
// be nil if no such labels should be set. fqName and help must not be empty.
// be nil if no such labels should be set. fqName must not be empty.
//
// variableLabels only contain the label names. Their label values are variable
// and therefore not part of the Desc. (They are managed within the Metric.)
//
// For constLabels, the label values are constant. Therefore, they are fully
// specified in the Desc. See the Opts documentation for the implications of
// constant labels.
// 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 help == "" {
d.err = errors.New("empty help string")
return d
}
if !model.IsValidMetricName(model.LabelValue(fqName)) {
d.err = fmt.Errorf("%q is not a valid metric name", fqName)
return d
@@ -111,7 +93,7 @@ func NewDesc(fqName, help string, variableLabels []string, constLabels Labels) *
// 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", labelName)
d.err = fmt.Errorf("%q is not a valid label name for metric %q", labelName, fqName)
return d
}
labelNames = append(labelNames, labelName)
@@ -122,12 +104,18 @@ func NewDesc(fqName, help string, variableLabels []string, constLabels Labels) *
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", labelName)
d.err = fmt.Errorf("%q is not a valid label name for metric %q", labelName, fqName)
return d
}
labelNames = append(labelNames, "$"+labelName)
@@ -137,6 +125,7 @@ func NewDesc(fqName, help string, variableLabels []string, constLabels Labels) *
d.err = errors.New("duplicate label names")
return d
}
vh := hashNew()
for _, val := range labelValues {
vh = hashAdd(vh, val)
@@ -163,7 +152,7 @@ func NewDesc(fqName, help string, variableLabels []string, constLabels Labels) *
Value: proto.String(v),
})
}
sort.Sort(LabelPairSorter(d.constLabelPairs))
sort.Sort(labelPairSorter(d.constLabelPairs))
return d
}
@@ -193,8 +182,3 @@ func (d *Desc) String() string {
d.variableLabels,
)
}
func checkLabelName(l string) bool {
return model.LabelName(l).IsValid() &&
!strings.HasPrefix(l, reservedLabelPrefix)
}

View File

@@ -11,10 +11,12 @@
// See the License for the specific language governing permissions and
// limitations under the License.
// Package prometheus provides metrics primitives to instrument code for
// monitoring. It also offers a registry for metrics. Sub-packages allow to
// expose the registered metrics via HTTP (package promhttp) or push them to a
// Pushgateway (package push).
// Package prometheus 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.
@@ -60,7 +62,7 @@
// // The Handler function provides a default handler to expose metrics
// // via an HTTP server. "/metrics" is the usual endpoint for that.
// http.Handle("/metrics", promhttp.Handler())
// log.Fatal(http.ListenAndServe(":8080", nil))
// log.Fatal(http.ListenAndServe(":8080", nil))
// }
//
//
@@ -72,7 +74,10 @@
// 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.
// 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
@@ -116,7 +121,17 @@
// NewConstSummary (and their respective Must… versions). That will happen in
// the Collect method. The Describe method has to return separate Desc
// instances, representative of the “throw-away” metrics to be created later.
// NewDesc comes in handy to create those Desc instances.
// NewDesc comes in handy to create those Desc instances. Alternatively, you
// could return no Desc at all, which will 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
@@ -145,7 +160,7 @@
// registry.
//
// So far, everything we did operated on the so-called default registry, as it
// can be found in the global DefaultRegistry variable. With NewRegistry, you
// can 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
@@ -153,11 +168,11 @@
//
// There are a number of uses for custom registries: You can use registries with
// special properties, see NewPedanticRegistry. You can avoid global state, as
// it is imposed by the DefaultRegistry. You can use multiple registries at the
// same time to expose different metrics in different ways. You can use separate
// registries for testing purposes.
// 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 DefaultRegistry comes registered with a Collector for Go
// 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.
@@ -168,7 +183,6 @@
// method can then expose the gathered metrics in some way. Usually, the metrics
// are served via HTTP on the /metrics endpoint. That's happening in the example
// above. The tools to expose metrics via HTTP are in the promhttp sub-package.
// (The top-level functions in the prometheus package are deprecated.)
//
// Pushing to the Pushgateway
//

View File

@@ -1,3 +1,16 @@
// Copyright 2018 The Prometheus Authors
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package prometheus
// Inline and byte-free variant of hash/fnv's fnv64a.

View File

@@ -13,6 +13,14 @@
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.
//
@@ -48,13 +56,74 @@ type Gauge interface {
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 {
return newValue(NewDesc(
desc := NewDesc(
BuildFQName(opts.Namespace, opts.Subsystem, opts.Name),
opts.Help,
nil,
opts.ConstLabels,
), GaugeValue, 0)
)
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
@@ -63,12 +132,11 @@ func NewGauge(opts GaugeOpts) Gauge {
// (e.g. number of operations queued, partitioned by user and operation
// type). Create instances with NewGaugeVec.
type GaugeVec struct {
*MetricVec
*metricVec
}
// NewGaugeVec creates a new GaugeVec based on the provided GaugeOpts and
// partitioned by the given label names. At least one label name must be
// provided.
// partitioned by the given label names.
func NewGaugeVec(opts GaugeOpts, labelNames []string) *GaugeVec {
desc := NewDesc(
BuildFQName(opts.Namespace, opts.Subsystem, opts.Name),
@@ -77,28 +145,62 @@ func NewGaugeVec(opts GaugeOpts, labelNames []string) *GaugeVec {
opts.ConstLabels,
)
return &GaugeVec{
MetricVec: newMetricVec(desc, func(lvs ...string) Metric {
return newValue(desc, GaugeValue, 0, lvs...)
metricVec: 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 replaces the method of the same name in
// MetricVec. The difference is that this method returns a Gauge and not a
// Metric so that no type conversion is required.
func (m *GaugeVec) GetMetricWithLabelValues(lvs ...string) (Gauge, error) {
metric, err := m.MetricVec.GetMetricWithLabelValues(lvs...)
// 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 replaces the method of the same name in MetricVec. The
// difference is that this method returns a Gauge and not a Metric so that no
// type conversion is required.
func (m *GaugeVec) GetMetricWith(labels Labels) (Gauge, error) {
metric, err := m.MetricVec.GetMetricWith(labels)
// 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
}
@@ -106,18 +208,57 @@ func (m *GaugeVec) GetMetricWith(labels Labels) (Gauge, error) {
}
// WithLabelValues works as GetMetricWithLabelValues, but panics where
// GetMetricWithLabelValues would have returned an error. By not returning an
// error, WithLabelValues allows shortcuts like
// GetMetricWithLabelValues would have returned an error. Not returning an
// error allows shortcuts like
// myVec.WithLabelValues("404", "GET").Add(42)
func (m *GaugeVec) WithLabelValues(lvs ...string) Gauge {
return m.MetricVec.WithLabelValues(lvs...).(Gauge)
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. By not returning an error, With allows shortcuts like
// myVec.With(Labels{"code": "404", "method": "GET"}).Add(42)
func (m *GaugeVec) With(labels Labels) Gauge {
return m.MetricVec.With(labels).(Gauge)
// 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

View File

@@ -1,9 +1,22 @@
// 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"
"runtime"
"runtime/debug"
"sync"
"time"
)
@@ -11,13 +24,43 @@ type goCollector struct {
goroutinesDesc *Desc
threadsDesc *Desc
gcDesc *Desc
goInfoDesc *Desc
// metrics to describe and collect
metrics memStatsMetrics
// 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 which exports metrics about the current
// go process.
// 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(
@@ -26,13 +69,21 @@ func NewGoCollector() Collector {
nil, nil),
threadsDesc: NewDesc(
"go_threads",
"Number of OS threads created",
"Number of OS threads created.",
nil, nil),
gcDesc: NewDesc(
"go_gc_duration_seconds",
"A summary of the GC invocation durations.",
nil, nil),
metrics: memStatsMetrics{
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"),
@@ -231,7 +282,7 @@ func NewGoCollector() Collector {
}
func memstatNamespace(s string) string {
return fmt.Sprintf("go_memstats_%s", s)
return "go_memstats_" + s
}
// Describe returns all descriptions of the collector.
@@ -239,13 +290,28 @@ func (c *goCollector) Describe(ch chan<- *Desc) {
ch <- c.goroutinesDesc
ch <- c.threadsDesc
ch <- c.gcDesc
for _, i := range c.metrics {
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))
@@ -259,11 +325,35 @@ func (c *goCollector) Collect(ch chan<- Metric) {
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), float64(stats.PauseTotal.Seconds()), quantiles)
ch <- MustNewConstSummary(c.gcDesc, uint64(stats.NumGC), stats.PauseTotal.Seconds(), quantiles)
ms := &runtime.MemStats{}
runtime.ReadMemStats(ms)
for _, i := range c.metrics {
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))
}
}
@@ -274,3 +364,33 @@ type memStatsMetrics []struct {
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
}

View File

@@ -16,7 +16,9 @@ package prometheus
import (
"fmt"
"math"
"runtime"
"sort"
"sync"
"sync/atomic"
"github.com/golang/protobuf/proto"
@@ -108,8 +110,9 @@ func ExponentialBuckets(start, factor float64, count int) []float64 {
}
// HistogramOpts bundles the options for creating a Histogram metric. It is
// mandatory to set Name and Help to a non-empty string. All other fields are
// optional and can safely be left at their zero value.
// 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
@@ -120,29 +123,22 @@ type HistogramOpts struct {
Subsystem string
Name string
// Help provides information about this Histogram. Mandatory!
// Help provides information about this Histogram.
//
// Metrics with the same fully-qualified name must have the same Help
// string.
Help string
// ConstLabels are used to attach fixed labels to this
// Histogram. Histograms with the same fully-qualified name must have the
// same label names in their ConstLabels.
// 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.
//
// Note that in most cases, labels have a value that varies during the
// lifetime of a process. Those labels are usually managed with a
// HistogramVec. ConstLabels serve only special purposes. One is for the
// special case where the value of a label does not change during the
// lifetime of a process, e.g. if the revision of the running binary is
// put into a label. Another, more advanced purpose is if more than one
// Collector needs to collect Histograms with the same fully-qualified
// name. In that case, those Summaries must differ in the values of
// their ConstLabels. See the Collector examples.
//
// If the value of a label never changes (not even between binaries),
// that label most likely should not be a label at all (but part of the
// metric name).
// 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
@@ -169,7 +165,7 @@ func NewHistogram(opts HistogramOpts) Histogram {
func newHistogram(desc *Desc, opts HistogramOpts, labelValues ...string) Histogram {
if len(desc.variableLabels) != len(labelValues) {
panic(errInconsistentCardinality)
panic(makeInconsistentCardinalityError(desc.fqName, desc.variableLabels, labelValues))
}
for _, n := range desc.variableLabels {
@@ -191,6 +187,7 @@ func newHistogram(desc *Desc, opts HistogramOpts, labelValues ...string) Histogr
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 {
@@ -207,30 +204,56 @@ func newHistogram(desc *Desc, opts HistogramOpts, labelValues ...string) Histogr
}
}
}
// Finally we know the final length of h.upperBounds and can make counts.
h.counts = make([]uint64, len(h.upperBounds))
// 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 histogram struct {
type histogramCounts struct {
// sumBits contains the bits of the float64 representing the sum of all
// observations. sumBits and count have to go first in the struct to
// guarantee alignment for atomic operations.
// http://golang.org/pkg/sync/atomic/#pkg-note-BUG
sumBits uint64
count uint64
buckets []uint64
}
type histogram struct {
// 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 hotcold 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
// Note that there is no mutex required.
desc *Desc
writeMtx sync.Mutex // Only used in the Write method.
desc *Desc
// 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
counts []uint64
labelPairs []*dto.LabelPair
labelPairs []*dto.LabelPair
}
func (h *histogram) Desc() *Desc {
@@ -248,36 +271,84 @@ func (h *histogram) Observe(v float64) {
// 100 buckets: 78.1 ns/op linear - binary 54.9 ns/op
// 300 buckets: 154 ns/op linear - binary 61.6 ns/op
i := sort.SearchFloat64s(h.upperBounds, v)
if i < len(h.counts) {
atomic.AddUint64(&h.counts[i], 1)
// We increment h.countAndHotIdx 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)
}
atomic.AddUint64(&h.count, 1)
for {
oldBits := atomic.LoadUint64(&h.sumBits)
oldBits := atomic.LoadUint64(&hotCounts.sumBits)
newBits := math.Float64bits(math.Float64frombits(oldBits) + v)
if atomic.CompareAndSwapUint64(&h.sumBits, oldBits, newBits) {
if atomic.CompareAndSwapUint64(&hotCounts.sumBits, oldBits, newBits) {
break
}
}
// Increment count last as we take it as a signal that the observation
// is complete.
atomic.AddUint64(&hotCounts.count, 1)
}
func (h *histogram) Write(out *dto.Metric) error {
his := &dto.Histogram{}
buckets := make([]*dto.Bucket, len(h.upperBounds))
// 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()
his.SampleSum = proto.Float64(math.Float64frombits(atomic.LoadUint64(&h.sumBits)))
his.SampleCount = proto.Uint64(atomic.LoadUint64(&h.count))
var count uint64
// 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 {
count += atomic.LoadUint64(&h.counts[i])
buckets[i] = &dto.Bucket{
CumulativeCount: proto.Uint64(count),
cumCount += atomic.LoadUint64(&coldCounts.buckets[i])
his.Bucket[i] = &dto.Bucket{
CumulativeCount: proto.Uint64(cumCount),
UpperBound: proto.Float64(upperBound),
}
}
his.Bucket = buckets
out.Histogram = his
out.Label = h.labelPairs
// Finally add all the cold counts to the new hot counts and reset the cold counts.
atomic.AddUint64(&hotCounts.count, count)
atomic.StoreUint64(&coldCounts.count, 0)
for {
oldBits := atomic.LoadUint64(&hotCounts.sumBits)
newBits := math.Float64bits(math.Float64frombits(oldBits) + his.GetSampleSum())
if atomic.CompareAndSwapUint64(&hotCounts.sumBits, oldBits, newBits) {
atomic.StoreUint64(&coldCounts.sumBits, 0)
break
}
}
for i := range h.upperBounds {
atomic.AddUint64(&hotCounts.buckets[i], atomic.LoadUint64(&coldCounts.buckets[i]))
atomic.StoreUint64(&coldCounts.buckets[i], 0)
}
return nil
}
@@ -287,12 +358,11 @@ func (h *histogram) Write(out *dto.Metric) error {
// (e.g. HTTP request latencies, partitioned by status code and method). Create
// instances with NewHistogramVec.
type HistogramVec struct {
*MetricVec
*metricVec
}
// NewHistogramVec creates a new HistogramVec based on the provided HistogramOpts and
// partitioned by the given label names. At least one label name must be
// provided.
// partitioned by the given label names.
func NewHistogramVec(opts HistogramOpts, labelNames []string) *HistogramVec {
desc := NewDesc(
BuildFQName(opts.Namespace, opts.Subsystem, opts.Name),
@@ -301,28 +371,58 @@ func NewHistogramVec(opts HistogramOpts, labelNames []string) *HistogramVec {
opts.ConstLabels,
)
return &HistogramVec{
MetricVec: newMetricVec(desc, func(lvs ...string) Metric {
metricVec: newMetricVec(desc, func(lvs ...string) Metric {
return newHistogram(desc, opts, lvs...)
}),
}
}
// GetMetricWithLabelValues replaces the method of the same name in
// MetricVec. The difference is that this method returns an Observer and not a
// Metric so that no type conversion to an Observer is required.
func (m *HistogramVec) GetMetricWithLabelValues(lvs ...string) (Observer, error) {
metric, err := m.MetricVec.GetMetricWithLabelValues(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 replaces the method of the same name in MetricVec. The
// difference is that this method returns an Observer and not a Metric so that no
// type conversion to an Observer is required.
func (m *HistogramVec) GetMetricWith(labels Labels) (Observer, error) {
metric, err := m.MetricVec.GetMetricWith(labels)
// 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
}
@@ -330,18 +430,57 @@ func (m *HistogramVec) GetMetricWith(labels Labels) (Observer, error) {
}
// WithLabelValues works as GetMetricWithLabelValues, but panics where
// GetMetricWithLabelValues would have returned an error. By not returning an
// error, WithLabelValues allows shortcuts like
// GetMetricWithLabelValues would have returned an error. Not returning an
// error allows shortcuts like
// myVec.WithLabelValues("404", "GET").Observe(42.21)
func (m *HistogramVec) WithLabelValues(lvs ...string) Observer {
return m.MetricVec.WithLabelValues(lvs...).(Observer)
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. By not returning an error, With allows shortcuts like
// myVec.With(Labels{"code": "404", "method": "GET"}).Observe(42.21)
func (m *HistogramVec) With(labels Labels) Observer {
return m.MetricVec.With(labels).(Observer)
// 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 {
@@ -393,7 +532,7 @@ func (h *constHistogram) Write(out *dto.Metric) error {
// bucket.
//
// NewConstHistogram returns an error if the length of labelValues is not
// consistent with the variable labels in Desc.
// consistent with the variable labels in Desc or if Desc is invalid.
func NewConstHistogram(
desc *Desc,
count uint64,
@@ -401,8 +540,11 @@ func NewConstHistogram(
buckets map[float64]uint64,
labelValues ...string,
) (Metric, error) {
if len(desc.variableLabels) != len(labelValues) {
return nil, errInconsistentCardinality
if desc.err != nil {
return nil, desc.err
}
if err := validateLabelValues(labelValues, len(desc.variableLabels)); err != nil {
return nil, err
}
return &constHistogram{
desc: desc,

View File

@@ -1,524 +0,0 @@
// 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 (
"bufio"
"bytes"
"compress/gzip"
"fmt"
"io"
"net"
"net/http"
"strconv"
"strings"
"sync"
"time"
"github.com/prometheus/common/expfmt"
)
// TODO(beorn7): Remove this whole file. It is a partial mirror of
// promhttp/http.go (to avoid circular import chains) where everything HTTP
// related should live. The functions here are just for avoiding
// breakage. Everything is deprecated.
const (
contentTypeHeader = "Content-Type"
contentLengthHeader = "Content-Length"
contentEncodingHeader = "Content-Encoding"
acceptEncodingHeader = "Accept-Encoding"
)
var bufPool sync.Pool
func getBuf() *bytes.Buffer {
buf := bufPool.Get()
if buf == nil {
return &bytes.Buffer{}
}
return buf.(*bytes.Buffer)
}
func giveBuf(buf *bytes.Buffer) {
buf.Reset()
bufPool.Put(buf)
}
// Handler returns an HTTP handler for the DefaultGatherer. It is
// already instrumented with InstrumentHandler (using "prometheus" as handler
// name).
//
// Deprecated: Please note the issues described in the doc comment of
// InstrumentHandler. You might want to consider using promhttp.Handler instead
// (which is not instrumented, but can be instrumented with the tooling provided
// in package promhttp).
func Handler() http.Handler {
return InstrumentHandler("prometheus", UninstrumentedHandler())
}
// UninstrumentedHandler returns an HTTP handler for the DefaultGatherer.
//
// Deprecated: Use promhttp.Handler instead. See there for further documentation.
func UninstrumentedHandler() http.Handler {
return http.HandlerFunc(func(w http.ResponseWriter, req *http.Request) {
mfs, err := DefaultGatherer.Gather()
if err != nil {
http.Error(w, "An error has occurred during metrics collection:\n\n"+err.Error(), http.StatusInternalServerError)
return
}
contentType := expfmt.Negotiate(req.Header)
buf := getBuf()
defer giveBuf(buf)
writer, encoding := decorateWriter(req, buf)
enc := expfmt.NewEncoder(writer, contentType)
var lastErr error
for _, mf := range mfs {
if err := enc.Encode(mf); err != nil {
lastErr = err
http.Error(w, "An error has occurred during metrics encoding:\n\n"+err.Error(), http.StatusInternalServerError)
return
}
}
if closer, ok := writer.(io.Closer); ok {
closer.Close()
}
if lastErr != nil && buf.Len() == 0 {
http.Error(w, "No metrics encoded, last error:\n\n"+err.Error(), http.StatusInternalServerError)
return
}
header := w.Header()
header.Set(contentTypeHeader, string(contentType))
header.Set(contentLengthHeader, fmt.Sprint(buf.Len()))
if encoding != "" {
header.Set(contentEncodingHeader, encoding)
}
w.Write(buf.Bytes())
})
}
// decorateWriter wraps a writer to handle gzip compression if requested. It
// returns the decorated writer and the appropriate "Content-Encoding" header
// (which is empty if no compression is enabled).
func decorateWriter(request *http.Request, writer io.Writer) (io.Writer, string) {
header := request.Header.Get(acceptEncodingHeader)
parts := strings.Split(header, ",")
for _, part := range parts {
part := strings.TrimSpace(part)
if part == "gzip" || strings.HasPrefix(part, "gzip;") {
return gzip.NewWriter(writer), "gzip"
}
}
return writer, ""
}
var instLabels = []string{"method", "code"}
type nower interface {
Now() time.Time
}
type nowFunc func() time.Time
func (n nowFunc) Now() time.Time {
return n()
}
var now nower = nowFunc(func() time.Time {
return time.Now()
})
func nowSeries(t ...time.Time) nower {
return nowFunc(func() time.Time {
defer func() {
t = t[1:]
}()
return t[0]
})
}
// InstrumentHandler wraps the given HTTP handler for instrumentation. It
// registers four metric collectors (if not already done) and reports HTTP
// metrics to the (newly or already) registered collectors: http_requests_total
// (CounterVec), http_request_duration_microseconds (Summary),
// http_request_size_bytes (Summary), http_response_size_bytes (Summary). Each
// has a constant label named "handler" with the provided handlerName as
// value. http_requests_total is a metric vector partitioned by HTTP method
// (label name "method") and HTTP status code (label name "code").
//
// Deprecated: InstrumentHandler has several issues. Use the tooling provided in
// package promhttp instead. The issues are the following:
//
// - It uses Summaries rather than Histograms. Summaries are not useful if
// aggregation across multiple instances is required.
//
// - It uses microseconds as unit, which is deprecated and should be replaced by
// seconds.
//
// - The size of the request is calculated in a separate goroutine. Since this
// calculator requires access to the request header, it creates a race with
// any writes to the header performed during request handling.
// httputil.ReverseProxy is a prominent example for a handler
// performing such writes.
//
// - It has additional issues with HTTP/2, cf.
// https://github.com/prometheus/client_golang/issues/272.
func InstrumentHandler(handlerName string, handler http.Handler) http.HandlerFunc {
return InstrumentHandlerFunc(handlerName, handler.ServeHTTP)
}
// InstrumentHandlerFunc wraps the given function for instrumentation. It
// otherwise works in the same way as InstrumentHandler (and shares the same
// issues).
//
// Deprecated: InstrumentHandlerFunc is deprecated for the same reasons as
// InstrumentHandler is. Use the tooling provided in package promhttp instead.
func InstrumentHandlerFunc(handlerName string, handlerFunc func(http.ResponseWriter, *http.Request)) http.HandlerFunc {
return InstrumentHandlerFuncWithOpts(
SummaryOpts{
Subsystem: "http",
ConstLabels: Labels{"handler": handlerName},
Objectives: map[float64]float64{0.5: 0.05, 0.9: 0.01, 0.99: 0.001},
},
handlerFunc,
)
}
// InstrumentHandlerWithOpts works like InstrumentHandler (and shares the same
// issues) but provides more flexibility (at the cost of a more complex call
// syntax). As InstrumentHandler, this function registers four metric
// collectors, but it uses the provided SummaryOpts to create them. However, the
// fields "Name" and "Help" in the SummaryOpts are ignored. "Name" is replaced
// by "requests_total", "request_duration_microseconds", "request_size_bytes",
// and "response_size_bytes", respectively. "Help" is replaced by an appropriate
// help string. The names of the variable labels of the http_requests_total
// CounterVec are "method" (get, post, etc.), and "code" (HTTP status code).
//
// If InstrumentHandlerWithOpts is called as follows, it mimics exactly the
// behavior of InstrumentHandler:
//
// prometheus.InstrumentHandlerWithOpts(
// prometheus.SummaryOpts{
// Subsystem: "http",
// ConstLabels: prometheus.Labels{"handler": handlerName},
// },
// handler,
// )
//
// Technical detail: "requests_total" is a CounterVec, not a SummaryVec, so it
// cannot use SummaryOpts. Instead, a CounterOpts struct is created internally,
// and all its fields are set to the equally named fields in the provided
// SummaryOpts.
//
// Deprecated: InstrumentHandlerWithOpts is deprecated for the same reasons as
// InstrumentHandler is. Use the tooling provided in package promhttp instead.
func InstrumentHandlerWithOpts(opts SummaryOpts, handler http.Handler) http.HandlerFunc {
return InstrumentHandlerFuncWithOpts(opts, handler.ServeHTTP)
}
// InstrumentHandlerFuncWithOpts works like InstrumentHandlerFunc (and shares
// the same issues) but provides more flexibility (at the cost of a more complex
// call syntax). See InstrumentHandlerWithOpts for details how the provided
// SummaryOpts are used.
//
// Deprecated: InstrumentHandlerFuncWithOpts is deprecated for the same reasons
// as InstrumentHandler is. Use the tooling provided in package promhttp instead.
func InstrumentHandlerFuncWithOpts(opts SummaryOpts, handlerFunc func(http.ResponseWriter, *http.Request)) http.HandlerFunc {
reqCnt := NewCounterVec(
CounterOpts{
Namespace: opts.Namespace,
Subsystem: opts.Subsystem,
Name: "requests_total",
Help: "Total number of HTTP requests made.",
ConstLabels: opts.ConstLabels,
},
instLabels,
)
if err := Register(reqCnt); err != nil {
if are, ok := err.(AlreadyRegisteredError); ok {
reqCnt = are.ExistingCollector.(*CounterVec)
} else {
panic(err)
}
}
opts.Name = "request_duration_microseconds"
opts.Help = "The HTTP request latencies in microseconds."
reqDur := NewSummary(opts)
if err := Register(reqDur); err != nil {
if are, ok := err.(AlreadyRegisteredError); ok {
reqDur = are.ExistingCollector.(Summary)
} else {
panic(err)
}
}
opts.Name = "request_size_bytes"
opts.Help = "The HTTP request sizes in bytes."
reqSz := NewSummary(opts)
if err := Register(reqSz); err != nil {
if are, ok := err.(AlreadyRegisteredError); ok {
reqSz = are.ExistingCollector.(Summary)
} else {
panic(err)
}
}
opts.Name = "response_size_bytes"
opts.Help = "The HTTP response sizes in bytes."
resSz := NewSummary(opts)
if err := Register(resSz); err != nil {
if are, ok := err.(AlreadyRegisteredError); ok {
resSz = are.ExistingCollector.(Summary)
} else {
panic(err)
}
}
return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
now := time.Now()
delegate := &responseWriterDelegator{ResponseWriter: w}
out := computeApproximateRequestSize(r)
_, cn := w.(http.CloseNotifier)
_, fl := w.(http.Flusher)
_, hj := w.(http.Hijacker)
_, rf := w.(io.ReaderFrom)
var rw http.ResponseWriter
if cn && fl && hj && rf {
rw = &fancyResponseWriterDelegator{delegate}
} else {
rw = delegate
}
handlerFunc(rw, r)
elapsed := float64(time.Since(now)) / float64(time.Microsecond)
method := sanitizeMethod(r.Method)
code := sanitizeCode(delegate.status)
reqCnt.WithLabelValues(method, code).Inc()
reqDur.Observe(elapsed)
resSz.Observe(float64(delegate.written))
reqSz.Observe(float64(<-out))
})
}
func computeApproximateRequestSize(r *http.Request) <-chan int {
// Get URL length in current go routine for avoiding a race condition.
// HandlerFunc that runs in parallel may modify the URL.
s := 0
if r.URL != nil {
s += len(r.URL.String())
}
out := make(chan int, 1)
go func() {
s += len(r.Method)
s += len(r.Proto)
for name, values := range r.Header {
s += len(name)
for _, value := range values {
s += len(value)
}
}
s += len(r.Host)
// N.B. r.Form and r.MultipartForm are assumed to be included in r.URL.
if r.ContentLength != -1 {
s += int(r.ContentLength)
}
out <- s
close(out)
}()
return out
}
type responseWriterDelegator struct {
http.ResponseWriter
handler, method string
status int
written int64
wroteHeader bool
}
func (r *responseWriterDelegator) WriteHeader(code int) {
r.status = code
r.wroteHeader = true
r.ResponseWriter.WriteHeader(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 fancyResponseWriterDelegator struct {
*responseWriterDelegator
}
func (f *fancyResponseWriterDelegator) CloseNotify() <-chan bool {
return f.ResponseWriter.(http.CloseNotifier).CloseNotify()
}
func (f *fancyResponseWriterDelegator) Flush() {
f.ResponseWriter.(http.Flusher).Flush()
}
func (f *fancyResponseWriterDelegator) Hijack() (net.Conn, *bufio.ReadWriter, error) {
return f.ResponseWriter.(http.Hijacker).Hijack()
}
func (f *fancyResponseWriterDelegator) ReadFrom(r io.Reader) (int64, error) {
if !f.wroteHeader {
f.WriteHeader(http.StatusOK)
}
n, err := f.ResponseWriter.(io.ReaderFrom).ReadFrom(r)
f.written += n
return n, err
}
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)
}
}
func sanitizeCode(s int) string {
switch s {
case 100:
return "100"
case 101:
return "101"
case 200:
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)
}
}

View File

@@ -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
}

View File

@@ -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)
}

View File

@@ -15,6 +15,9 @@ package prometheus
import (
"strings"
"time"
"github.com/golang/protobuf/proto"
dto "github.com/prometheus/client_model/go"
)
@@ -43,9 +46,8 @@ type Metric interface {
// While populating dto.Metric, it is the responsibility of the
// implementation to ensure validity of the Metric protobuf (like valid
// UTF-8 strings or syntactically valid metric and label names). It is
// recommended to sort labels lexicographically. (Implementers may find
// LabelPairSorter useful for that.) Callers of Write should still make
// sure of sorting if they depend on it.
// 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
@@ -57,8 +59,9 @@ type Metric interface {
// implementation XXX has its own XXXOpts type, but in most cases, it is just be
// an alias of this type (which might change when the requirement arises.)
//
// It is mandatory to set Name and Help to a non-empty string. All other fields
// are optional and can safely be left at their zero value.
// 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
@@ -69,7 +72,7 @@ type Opts struct {
Subsystem string
Name string
// Help provides information about this metric. Mandatory!
// Help provides information about this metric.
//
// Metrics with the same fully-qualified name must have the same Help
// string.
@@ -79,20 +82,12 @@ type Opts struct {
// with the same fully-qualified name must have the same label names in
// their ConstLabels.
//
// Note that in most cases, labels have a value that varies during the
// lifetime of a process. Those labels are usually managed with a metric
// vector collector (like CounterVec, GaugeVec, UntypedVec). ConstLabels
// serve only special purposes. One is for the special case where the
// value of a label does not change during the lifetime of a process,
// e.g. if the revision of the running binary is put into a
// label. Another, more advanced purpose is if more than one Collector
// needs to collect Metrics with the same fully-qualified name. In that
// case, those Metrics must differ in the values of their
// ConstLabels. See the Collector examples.
//
// If the value of a label never changes (not even between binaries),
// that label most likely should not be a label at all (but part of the
// metric name).
// 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
}
@@ -118,37 +113,22 @@ func BuildFQName(namespace, subsystem, name string) string {
return name
}
// LabelPairSorter implements sort.Interface. It is used to sort a slice of
// dto.LabelPair pointers. This is useful for implementing the Write method of
// custom metrics.
type LabelPairSorter []*dto.LabelPair
// labelPairSorter implements sort.Interface. It is used to sort a slice of
// dto.LabelPair pointers.
type labelPairSorter []*dto.LabelPair
func (s LabelPairSorter) Len() int {
func (s labelPairSorter) Len() int {
return len(s)
}
func (s LabelPairSorter) Swap(i, j int) {
func (s labelPairSorter) Swap(i, j int) {
s[i], s[j] = s[j], s[i]
}
func (s LabelPairSorter) Less(i, j int) bool {
func (s labelPairSorter) Less(i, j int) bool {
return s[i].GetName() < s[j].GetName()
}
type hashSorter []uint64
func (s hashSorter) Len() int {
return len(s)
}
func (s hashSorter) Swap(i, j int) {
s[i], s[j] = s[j], s[i]
}
func (s hashSorter) Less(i, j int) bool {
return s[i] < s[j]
}
type invalidMetric struct {
desc *Desc
err error
@@ -164,3 +144,31 @@ func NewInvalidMetric(desc *Desc, err error) Metric {
func (m *invalidMetric) Desc() *Desc { return m.desc }
func (m *invalidMetric) Write(*dto.Metric) error { return m.err }
type timestampedMetric struct {
Metric
t time.Time
}
func (m timestampedMetric) Write(pb *dto.Metric) error {
e := m.Metric.Write(pb)
pb.TimestampMs = proto.Int64(m.t.Unix()*1000 + int64(m.t.Nanosecond()/1000000))
return e
}
// NewMetricWithTimestamp returns a new Metric wrapping the provided Metric in a
// way that it has an explicit timestamp set to the provided Time. This is only
// useful in rare cases as the timestamp of a Prometheus metric should usually
// be set by the Prometheus server during scraping. Exceptions include mirroring
// metrics with given timestamps from other metric
// sources.
//
// NewMetricWithTimestamp works best with MustNewConstMetric,
// MustNewConstHistogram, and MustNewConstSummary, see example.
//
// Currently, the exposition formats used by Prometheus are limited to
// millisecond resolution. Thus, the provided time will be rounded down to the
// next full millisecond value.
func NewMetricWithTimestamp(t time.Time, m Metric) Metric {
return timestampedMetric{Metric: m, t: t}
}

View File

@@ -45,6 +45,8 @@ type ObserverVec interface {
GetMetricWithLabelValues(lvs ...string) (Observer, error)
With(Labels) Observer
WithLabelValues(...string) Observer
CurryWith(Labels) (ObserverVec, error)
MustCurryWith(Labels) ObserverVec
Collector
}

View File

@@ -13,46 +13,61 @@
package prometheus
import "github.com/prometheus/procfs"
import (
"errors"
"os"
)
type processCollector struct {
pid int
collectFn func(chan<- Metric)
pidFn func() (int, error)
reportErrors bool
cpuTotal *Desc
openFDs, maxFDs *Desc
vsize, rss *Desc
vsize, maxVsize *Desc
rss *Desc
startTime *Desc
}
// NewProcessCollector returns a collector which exports the current state of
// process metrics including cpu, memory and file descriptor usage as well as
// the process start time for the given process id under the given namespace.
func NewProcessCollector(pid int, namespace string) Collector {
return NewProcessCollectorPIDFn(
func() (int, error) { return pid, nil },
namespace,
)
// 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
}
// NewProcessCollectorPIDFn 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 under the given namespace. The given pidFn is
// called on each collect and is used to determine the process to export
// metrics for.
func NewProcessCollectorPIDFn(
pidFn func() (int, error),
namespace string,
) Collector {
// 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(namespace) > 0 {
ns = namespace + "_"
if len(opts.Namespace) > 0 {
ns = opts.Namespace + "_"
}
c := processCollector{
pidFn: pidFn,
collectFn: func(chan<- Metric) {},
c := &processCollector{
reportErrors: opts.ReportErrors,
cpuTotal: NewDesc(
ns+"process_cpu_seconds_total",
"Total user and system CPU time spent in seconds.",
@@ -73,6 +88,11 @@ func NewProcessCollectorPIDFn(
"Virtual memory size in bytes.",
nil, nil,
),
maxVsize: NewDesc(
ns+"process_virtual_memory_max_bytes",
"Maximum amount of virtual memory available in bytes.",
nil, nil,
),
rss: NewDesc(
ns+"process_resident_memory_bytes",
"Resident memory size in bytes.",
@@ -85,12 +105,23 @@ func NewProcessCollectorPIDFn(
),
}
// Set up process metric collection if supported by the runtime.
if _, err := procfs.NewStat(); err == nil {
c.collectFn = c.processCollect
if opts.PidFn == nil {
pid := os.Getpid()
c.pidFn = func() (int, error) { return pid, nil }
} else {
c.pidFn = opts.PidFn
}
return &c
// 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.
@@ -99,6 +130,7 @@ func (c *processCollector) Describe(ch chan<- *Desc) {
ch <- c.openFDs
ch <- c.maxFDs
ch <- c.vsize
ch <- c.maxVsize
ch <- c.rss
ch <- c.startTime
}
@@ -108,33 +140,12 @@ func (c *processCollector) Collect(ch chan<- Metric) {
c.collectFn(ch)
}
// TODO(ts): Bring back error reporting by reverting 7faf9e7 as soon as the
// client allows users to configure the error behavior.
func (c *processCollector) processCollect(ch chan<- Metric) {
pid, err := c.pidFn()
if err != nil {
func (c *processCollector) reportError(ch chan<- Metric, desc *Desc, err error) {
if !c.reportErrors {
return
}
p, err := procfs.NewProc(pid)
if err != nil {
return
}
if stat, err := p.NewStat(); 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)
}
}
if fds, err := p.FileDescriptorsLen(); err == nil {
ch <- MustNewConstMetric(c.openFDs, GaugeValue, float64(fds))
}
if limits, err := p.NewLimits(); err == nil {
ch <- MustNewConstMetric(c.maxFDs, GaugeValue, float64(limits.OpenFiles))
if desc == nil {
desc = NewInvalidDesc(err)
}
ch <- NewInvalidMetric(desc, err)
}

View File

@@ -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)
}
}

View File

@@ -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
}

View File

@@ -15,15 +15,22 @@ package prometheus
import (
"bytes"
"errors"
"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 (
@@ -35,13 +42,14 @@ const (
// 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 (see NewProcessCollector) and a Go collector (see
// NewGoCollector) 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 function and act on custom
// instances instead.
// 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
@@ -49,7 +57,7 @@ var (
)
func init() {
MustRegister(NewProcessCollector(os.Getpid(), ""))
MustRegister(NewProcessCollector(ProcessCollectorOpts{}))
MustRegister(NewGoCollector())
}
@@ -65,7 +73,8 @@ func NewRegistry() *Registry {
// NewPedanticRegistry returns a registry that checks during collection if each
// collected Metric is consistent with its reported Desc, and if the Desc has
// actually been registered with the registry.
// actually been registered with the registry. Unchecked Collectors (those whose
// Describe methed does not yield any descriptors) are excluded from the check.
//
// Usually, a Registry will be happy as long as the union of all collected
// Metrics is consistent and valid even if some metrics are not consistent with
@@ -80,7 +89,7 @@ func NewPedanticRegistry() *Registry {
// 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 then the Registry type
// 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 {
@@ -95,8 +104,13 @@ type Registerer interface {
// returned error is an instance of AlreadyRegisteredError, which
// contains the previously registered Collector.
//
// It is in general not safe to register the same Collector multiple
// times concurrently.
// 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
@@ -105,7 +119,9 @@ type Registerer interface {
// Unregister unregisters the Collector that equals the Collector passed
// in as an argument. (Two Collectors are considered equal if their
// Describe method yields the same set of descriptors.) The function
// returns whether a Collector was unregistered.
// returns whether a Collector was unregistered. Note that an unchecked
// Collector cannot be unregistered (as its Describe method does not
// yield any descriptor).
//
// Note that even after unregistering, it will not be possible to
// register a new Collector that is inconsistent with the unregistered
@@ -123,15 +139,23 @@ type 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 MetricFamily protobufs. 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. In scenarios
// where complete collection is critical, the returned MetricFamily
// protobufs should be disregarded if the returned error is non-nil.
// 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)
}
@@ -201,6 +225,13 @@ func (errs MultiError) Error() string {
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
@@ -225,6 +256,7 @@ type Registry struct {
collectorsByID map[uint64]Collector // ID is a hash of the descIDs.
descIDs map[uint64]struct{}
dimHashesByName map[string]uint64
uncheckedCollectors []Collector
pedanticChecksEnabled bool
}
@@ -242,7 +274,12 @@ func (r *Registry) Register(c Collector) error {
close(descChan)
}()
r.mtx.Lock()
defer r.mtx.Unlock()
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 {
@@ -282,14 +319,23 @@ func (r *Registry) Register(c Collector) error {
}
}
}
// Did anything happen at all?
// A Collector yielding no Desc at all is considered unchecked.
if len(newDescIDs) == 0 {
return errors.New("collector has no descriptors")
r.uncheckedCollectors = append(r.uncheckedCollectors, c)
return nil
}
if existing, exists := r.collectorsByID[collectorID]; exists {
return AlreadyRegisteredError{
ExistingCollector: existing,
NewCollector: c,
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
@@ -358,31 +404,25 @@ func (r *Registry) MustRegister(cs ...Collector) {
// Gather implements Gatherer.
func (r *Registry) Gather() ([]*dto.MetricFamily, error) {
var (
metricChan = make(chan Metric, capMetricChan)
metricHashes = map[uint64]struct{}{}
dimHashes = map[string]uint64{}
wg sync.WaitGroup
errs MultiError // The collected errors to return in the end.
registeredDescIDs map[uint64]struct{} // Only used for pedantic checks
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))
// Scatter.
// (Collectors could be complex and slow, so we call them all at once.)
wg.Add(len(r.collectorsByID))
go func() {
wg.Wait()
close(metricChan)
}()
checkedCollectors := make(chan Collector, len(r.collectorsByID))
uncheckedCollectors := make(chan Collector, len(r.uncheckedCollectors))
for _, collector := range r.collectorsByID {
go func(collector Collector) {
defer wg.Done()
collector.Collect(metricChan)
}(collector)
checkedCollectors <- collector
}
for _, collector := range r.uncheckedCollectors {
uncheckedCollectors <- collector
}
// In case pedantic checks are enabled, we have to copy the map before
// giving up the RLock.
if r.pedanticChecksEnabled {
@@ -391,133 +431,264 @@ func (r *Registry) Gather() ([]*dto.MetricFamily, error) {
registeredDescIDs[id] = struct{}{}
}
}
r.mtx.RUnlock()
// Drain metricChan in case of premature return.
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() {
for range metricChan {
if checkedMetricChan != nil {
for range checkedMetricChan {
}
}
if uncheckedMetricChan != nil {
for range uncheckedMetricChan {
}
}
}()
// Gather.
for metric := range metricChan {
// This could be done concurrently, too, but it required locking
// of metricFamiliesByName (and of metricHashes if checks are
// enabled). Most likely not worth it.
desc := metric.Desc()
dtoMetric := &dto.Metric{}
if err := metric.Write(dtoMetric); err != nil {
errs = append(errs, fmt.Errorf(
"error collecting metric %v: %s", desc, err,
// 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,
))
continue
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()
}
metricFamily, ok := metricFamiliesByName[desc.fqName]
if ok {
if metricFamily.GetHelp() != desc.help {
errs = append(errs, fmt.Errorf(
"collected metric %s %s has help %q but should have %q",
desc.fqName, dtoMetric, desc.help, metricFamily.GetHelp(),
))
continue
}
// TODO(beorn7): Simplify switch once Desc has type.
switch metricFamily.GetType() {
case dto.MetricType_COUNTER:
if dtoMetric.Counter == nil {
errs = append(errs, fmt.Errorf(
"collected metric %s %s should be a Counter",
desc.fqName, dtoMetric,
))
continue
}
case dto.MetricType_GAUGE:
if dtoMetric.Gauge == nil {
errs = append(errs, fmt.Errorf(
"collected metric %s %s should be a Gauge",
desc.fqName, dtoMetric,
))
continue
}
case dto.MetricType_SUMMARY:
if dtoMetric.Summary == nil {
errs = append(errs, fmt.Errorf(
"collected metric %s %s should be a Summary",
desc.fqName, dtoMetric,
))
continue
}
case dto.MetricType_UNTYPED:
if dtoMetric.Untyped == nil {
errs = append(errs, fmt.Errorf(
"collected metric %s %s should be Untyped",
desc.fqName, dtoMetric,
))
continue
}
case dto.MetricType_HISTOGRAM:
if dtoMetric.Histogram == nil {
errs = append(errs, fmt.Errorf(
"collected metric %s %s should be a Histogram",
desc.fqName, dtoMetric,
))
continue
}
default:
panic("encountered MetricFamily with invalid type")
}
} else {
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:
errs = append(errs, fmt.Errorf(
"empty metric collected: %s", dtoMetric,
))
continue
}
metricFamiliesByName[desc.fqName] = metricFamily
// 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
}
if err := checkMetricConsistency(metricFamily, dtoMetric, metricHashes, dimHashes); err != nil {
errs = append(errs, err)
continue
}
if r.pedanticChecksEnabled {
// Is the desc registered at all?
if _, exist := registeredDescIDs[desc.id]; !exist {
errs = append(errs, fmt.Errorf(
"collected metric %s %s with unregistered descriptor %s",
metricFamily.GetName(), dtoMetric, desc,
))
continue
}
if err := checkDescConsistency(metricFamily, dtoMetric, desc); err != nil {
errs = append(errs, err)
continue
}
}
metricFamily.Metric = append(metricFamily.Metric, dtoMetric)
}
return normalizeMetricFamilies(metricFamiliesByName), errs.MaybeUnwrap()
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 calles are all returned in a flattened MultiError. Duplicate and
// 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.
//
@@ -537,7 +708,6 @@ func (gs Gatherers) Gather() ([]*dto.MetricFamily, error) {
var (
metricFamiliesByName = map[string]*dto.MetricFamily{}
metricHashes = map[uint64]struct{}{}
dimHashes = map[string]uint64{}
errs MultiError // The collected errors to return in the end.
)
@@ -574,10 +744,14 @@ func (gs Gatherers) Gather() ([]*dto.MetricFamily, error) {
existingMF.Name = mf.Name
existingMF.Help = mf.Help
existingMF.Type = mf.Type
if err := checkSuffixCollisions(existingMF, metricFamiliesByName); err != nil {
errs = append(errs, err)
continue
}
metricFamiliesByName[mf.GetName()] = existingMF
}
for _, m := range mf.Metric {
if err := checkMetricConsistency(existingMF, m, metricHashes, dimHashes); err != nil {
if err := checkMetricConsistency(existingMF, m, metricHashes); err != nil {
errs = append(errs, err)
continue
}
@@ -585,88 +759,80 @@ func (gs Gatherers) Gather() ([]*dto.MetricFamily, error) {
}
}
}
return normalizeMetricFamilies(metricFamiliesByName), errs.MaybeUnwrap()
return internal.NormalizeMetricFamilies(metricFamiliesByName), errs.MaybeUnwrap()
}
// metricSorter is a sortable slice of *dto.Metric.
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)
// 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]
}
for n, lp := range s[i].Label {
vi := lp.GetValue()
vj := s[j].Label[n].GetValue()
if vi != vj {
return vi < vj
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,
)
}
}
}
// 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)
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",
)
}
}
sort.Strings(names)
result := make([]*dto.MetricFamily, 0, len(names))
for _, name := range names {
result = append(result, metricFamiliesByName[name])
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 result
return nil
}
// checkMetricConsistency checks if the provided Metric is consistent with the
// provided MetricFamily. It also hashed the Metric labels and the MetricFamily
// name. If the resulting hash is alread in the provided metricHashes, an error
// is returned. If not, it is added to metricHashes. The provided dimHashes maps
// MetricFamily names to their dimHash (hashed sorted label names). If dimHashes
// doesn't yet contain a hash for the provided MetricFamily, it is
// added. Otherwise, an error is returned if the existing dimHashes in not equal
// the calculated dimHash.
// 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{},
dimHashes map[string]uint64,
) 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 ||
@@ -674,41 +840,65 @@ func checkMetricConsistency(
metricFamily.GetType() == dto.MetricType_HISTOGRAM && dtoMetric.Histogram == nil ||
metricFamily.GetType() == dto.MetricType_UNTYPED && dtoMetric.Untyped == nil {
return fmt.Errorf(
"collected metric %s %s is not a %s",
metricFamily.GetName(), dtoMetric, metricFamily.GetType(),
"collected metric %q { %s} is not a %s",
name, dtoMetric, metricFamily.GetType(),
)
}
// Is the metric unique (i.e. no other metric with the same name and the same label values)?
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, metricFamily.GetName())
h = hashAdd(h, name)
h = hashAddByte(h, separatorByte)
dh := hashNew()
// Make sure label pairs are sorted. We depend on it for the consistency
// check.
sort.Sort(LabelPairSorter(dtoMetric.Label))
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)
dh = hashAdd(dh, lp.GetName())
dh = hashAddByte(dh, separatorByte)
}
if _, exists := metricHashes[h]; exists {
return fmt.Errorf(
"collected metric %s %s was collected before with the same name and label values",
metricFamily.GetName(), dtoMetric,
"collected metric %q { %s} was collected before with the same name and label values",
name, dtoMetric,
)
}
if dimHash, ok := dimHashes[metricFamily.GetName()]; ok {
if dimHash != dh {
return fmt.Errorf(
"collected metric %s %s has label dimensions inconsistent with previously collected metrics in the same metric family",
metricFamily.GetName(), dtoMetric,
)
}
} else {
dimHashes[metricFamily.GetName()] = dh
}
metricHashes[h] = struct{}{}
return nil
}
@@ -727,8 +917,8 @@ func checkDescConsistency(
}
// Is the desc consistent with the content of the metric?
lpsFromDesc := make([]*dto.LabelPair, 0, len(dtoMetric.Label))
lpsFromDesc = append(lpsFromDesc, desc.constLabelPairs...)
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),
@@ -740,7 +930,7 @@ func checkDescConsistency(
metricFamily.GetName(), dtoMetric, desc,
)
}
sort.Sort(LabelPairSorter(lpsFromDesc))
sort.Sort(labelPairSorter(lpsFromDesc))
for i, lpFromDesc := range lpsFromDesc {
lpFromMetric := dtoMetric.Label[i]
if lpFromDesc.GetName() != lpFromMetric.GetName() ||

View File

@@ -16,8 +16,10 @@ package prometheus
import (
"fmt"
"math"
"runtime"
"sort"
"sync"
"sync/atomic"
"time"
"github.com/beorn7/perks/quantile"
@@ -36,7 +38,10 @@ const quantileLabel = "quantile"
//
// A typical use-case is the observation of request latencies. By default, a
// Summary provides the median, the 90th and the 99th percentile of the latency
// as rank estimations.
// 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
@@ -53,16 +58,8 @@ type Summary interface {
Observe(float64)
}
// DefObjectives are the default Summary quantile values.
//
// Deprecated: DefObjectives will not be used as the default objectives in
// v0.10 of the library. The default Summary will have no quantiles then.
var (
DefObjectives = map[float64]float64{0.5: 0.05, 0.9: 0.01, 0.99: 0.001}
errQuantileLabelNotAllowed = fmt.Errorf(
"%q is not allowed as label name in summaries", quantileLabel,
)
var errQuantileLabelNotAllowed = fmt.Errorf(
"%q is not allowed as label name in summaries", quantileLabel,
)
// Default values for SummaryOpts.
@@ -78,8 +75,10 @@ const (
)
// SummaryOpts bundles the options for creating a Summary metric. It is
// mandatory to set Name and Help to a non-empty string. All other fields are
// optional and can safely be left at their zero value.
// 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
@@ -90,41 +89,34 @@ type SummaryOpts struct {
Subsystem string
Name string
// Help provides information about this Summary. Mandatory!
// Help provides information about this Summary.
//
// Metrics with the same fully-qualified name must have the same Help
// string.
Help string
// ConstLabels are used to attach fixed labels to this
// Summary. Summaries with the same fully-qualified name must have the
// same label names in their ConstLabels.
// 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.
//
// Note that in most cases, labels have a value that varies during the
// lifetime of a process. Those labels are usually managed with a
// SummaryVec. ConstLabels serve only special purposes. One is for the
// special case where the value of a label does not change during the
// lifetime of a process, e.g. if the revision of the running binary is
// put into a label. Another, more advanced purpose is if more than one
// Collector needs to collect Summaries with the same fully-qualified
// name. In that case, those Summaries must differ in the values of
// their ConstLabels. See the Collector examples.
// 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.
//
// If the value of a label never changes (not even between binaries),
// that label most likely should not be a label at all (but part of the
// metric name).
// 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 DefObjectives. It is used if Objectives is left at
// its zero value (i.e. nil). To create a Summary without Objectives,
// set it to an empty map (i.e. map[float64]float64{}).
//
// Deprecated: Note that the current value of DefObjectives is
// deprecated. It will be replaced by an empty map in v0.10 of the
// library. Please explicitly set Objectives to the desired value.
// 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
@@ -148,7 +140,7 @@ type SummaryOpts struct {
BufCap uint32
}
// Great fuck-up with the sliding-window decay algorithm... The Merge method of
// 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
@@ -178,7 +170,7 @@ func NewSummary(opts SummaryOpts) Summary {
func newSummary(desc *Desc, opts SummaryOpts, labelValues ...string) Summary {
if len(desc.variableLabels) != len(labelValues) {
panic(errInconsistentCardinality)
panic(makeInconsistentCardinalityError(desc.fqName, desc.variableLabels, labelValues))
}
for _, n := range desc.variableLabels {
@@ -193,7 +185,7 @@ func newSummary(desc *Desc, opts SummaryOpts, labelValues ...string) Summary {
}
if opts.Objectives == nil {
opts.Objectives = DefObjectives
opts.Objectives = map[float64]float64{}
}
if opts.MaxAge < 0 {
@@ -211,6 +203,17 @@ func newSummary(desc *Desc, opts SummaryOpts, labelValues ...string) Summary {
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,
@@ -379,6 +382,116 @@ func (s *summary) swapBufs(now time.Time) {
}
}
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 hotcold 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 {
@@ -399,13 +512,21 @@ func (s quantSort) Less(i, j int) bool {
// (e.g. HTTP request latencies, partitioned by status code and method). Create
// instances with NewSummaryVec.
type SummaryVec struct {
*MetricVec
*metricVec
}
// NewSummaryVec creates a new SummaryVec based on the provided SummaryOpts and
// partitioned by the given label names. At least one label name must be
// provided.
// 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,
@@ -413,28 +534,58 @@ func NewSummaryVec(opts SummaryOpts, labelNames []string) *SummaryVec {
opts.ConstLabels,
)
return &SummaryVec{
MetricVec: newMetricVec(desc, func(lvs ...string) Metric {
metricVec: newMetricVec(desc, func(lvs ...string) Metric {
return newSummary(desc, opts, lvs...)
}),
}
}
// GetMetricWithLabelValues replaces the method of the same name in MetricVec.
// The difference is that this method returns an Observer and not a Metric so
// that no type conversion to an Observer is required.
func (m *SummaryVec) GetMetricWithLabelValues(lvs ...string) (Observer, error) {
metric, err := m.MetricVec.GetMetricWithLabelValues(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 replaces the method of the same name in MetricVec. The
// difference is that this method returns an Observer and not a Metric so that
// no type conversion to an Observer is required.
func (m *SummaryVec) GetMetricWith(labels Labels) (Observer, error) {
metric, err := m.MetricVec.GetMetricWith(labels)
// 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
}
@@ -442,18 +593,57 @@ func (m *SummaryVec) GetMetricWith(labels Labels) (Observer, error) {
}
// WithLabelValues works as GetMetricWithLabelValues, but panics where
// GetMetricWithLabelValues would have returned an error. By not returning an
// error, WithLabelValues allows shortcuts like
// GetMetricWithLabelValues would have returned an error. Not returning an
// error allows shortcuts like
// myVec.WithLabelValues("404", "GET").Observe(42.21)
func (m *SummaryVec) WithLabelValues(lvs ...string) Observer {
return m.MetricVec.WithLabelValues(lvs...).(Observer)
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. By not returning an error, With allows shortcuts like
// myVec.With(Labels{"code": "404", "method": "GET"}).Observe(42.21)
func (m *SummaryVec) With(labels Labels) Observer {
return m.MetricVec.With(labels).(Observer)
// 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 {
@@ -506,7 +696,7 @@ func (s *constSummary) Write(out *dto.Metric) error {
// map[float64]float64{0.5: 0.23, 0.99: 0.56}
//
// NewConstSummary returns an error if the length of labelValues is not
// consistent with the variable labels in Desc.
// consistent with the variable labels in Desc or if Desc is invalid.
func NewConstSummary(
desc *Desc,
count uint64,
@@ -514,8 +704,11 @@ func NewConstSummary(
quantiles map[float64]float64,
labelValues ...string,
) (Metric, error) {
if len(desc.variableLabels) != len(labelValues) {
return nil, errInconsistentCardinality
if desc.err != nil {
return nil, desc.err
}
if err := validateLabelValues(labelValues, len(desc.variableLabels)); err != nil {
return nil, err
}
return &constSummary{
desc: desc,

View File

@@ -39,10 +39,16 @@ func NewTimer(o Observer) *Timer {
// ObserveDuration records the duration passed since the Timer was created with
// NewTimer. It calls the Observe method of the Observer provided during
// construction with the duration in seconds as an argument. ObserveDuration is
// usually called with a defer statement.
func (t *Timer) ObserveDuration() {
// 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(time.Since(t.begin).Seconds())
t.observer.Observe(d.Seconds())
}
return d
}

View File

@@ -13,113 +13,12 @@
package prometheus
// Untyped is a Metric that represents a single numerical value that can
// arbitrarily go up and down.
//
// An Untyped metric works the same as a Gauge. The only difference is that to
// no type information is implied.
//
// To create Untyped instances, use NewUntyped.
//
// Deprecated: The Untyped type is deprecated because it doesn't make sense in
// direct instrumentation. If you need to mirror an external metric of unknown
// type (usually while writing exporters), Use MustNewConstMetric to create an
// untyped metric instance on the fly.
type Untyped interface {
Metric
Collector
// Set sets the Untyped metric to an arbitrary value.
Set(float64)
// Inc increments the Untyped metric by 1.
Inc()
// Dec decrements the Untyped metric by 1.
Dec()
// Add adds the given value to the Untyped metric. (The value can be
// negative, resulting in a decrease.)
Add(float64)
// Sub subtracts the given value from the Untyped metric. (The value can
// be negative, resulting in an increase.)
Sub(float64)
}
// UntypedOpts is an alias for Opts. See there for doc comments.
type UntypedOpts Opts
// NewUntyped creates a new Untyped metric from the provided UntypedOpts.
func NewUntyped(opts UntypedOpts) Untyped {
return newValue(NewDesc(
BuildFQName(opts.Namespace, opts.Subsystem, opts.Name),
opts.Help,
nil,
opts.ConstLabels,
), UntypedValue, 0)
}
// UntypedVec is a Collector that bundles a set of Untyped metrics 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. Create instances with NewUntypedVec.
type UntypedVec struct {
*MetricVec
}
// NewUntypedVec creates a new UntypedVec based on the provided UntypedOpts and
// partitioned by the given label names. At least one label name must be
// provided.
func NewUntypedVec(opts UntypedOpts, labelNames []string) *UntypedVec {
desc := NewDesc(
BuildFQName(opts.Namespace, opts.Subsystem, opts.Name),
opts.Help,
labelNames,
opts.ConstLabels,
)
return &UntypedVec{
MetricVec: newMetricVec(desc, func(lvs ...string) Metric {
return newValue(desc, UntypedValue, 0, lvs...)
}),
}
}
// GetMetricWithLabelValues replaces the method of the same name in
// MetricVec. The difference is that this method returns an Untyped and not a
// Metric so that no type conversion is required.
func (m *UntypedVec) GetMetricWithLabelValues(lvs ...string) (Untyped, error) {
metric, err := m.MetricVec.GetMetricWithLabelValues(lvs...)
if metric != nil {
return metric.(Untyped), err
}
return nil, err
}
// GetMetricWith replaces the method of the same name in MetricVec. The
// difference is that this method returns an Untyped and not a Metric so that no
// type conversion is required.
func (m *UntypedVec) GetMetricWith(labels Labels) (Untyped, error) {
metric, err := m.MetricVec.GetMetricWith(labels)
if metric != nil {
return metric.(Untyped), err
}
return nil, err
}
// WithLabelValues works as GetMetricWithLabelValues, but panics where
// GetMetricWithLabelValues would have returned an error. By not returning an
// error, WithLabelValues allows shortcuts like
// myVec.WithLabelValues("404", "GET").Add(42)
func (m *UntypedVec) WithLabelValues(lvs ...string) Untyped {
return m.MetricVec.WithLabelValues(lvs...).(Untyped)
}
// With works as GetMetricWith, but panics where GetMetricWithLabels would have
// returned an error. By not returning an error, With allows shortcuts like
// myVec.With(Labels{"code": "404", "method": "GET"}).Add(42)
func (m *UntypedVec) With(labels Labels) Untyped {
return m.MetricVec.With(labels).(Untyped)
}
// UntypedFunc is an Untyped whose value is determined at collect time by
// calling a provided function.
// 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 {

View File

@@ -14,16 +14,12 @@
package prometheus
import (
"errors"
"fmt"
"math"
"sort"
"sync/atomic"
"time"
dto "github.com/prometheus/client_model/go"
"github.com/golang/protobuf/proto"
dto "github.com/prometheus/client_model/go"
)
// ValueType is an enumeration of metric types that represent a simple value.
@@ -37,81 +33,6 @@ const (
UntypedValue
)
var errInconsistentCardinality = errors.New("inconsistent label cardinality")
// value is a generic metric for simple values. It implements Metric, Collector,
// Counter, Gauge, and Untyped. Its effective type is determined by
// ValueType. This is a low-level building block used by the library to back the
// implementations of Counter, Gauge, and Untyped.
type value struct {
// valBits 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
valType ValueType
labelPairs []*dto.LabelPair
}
// newValue returns a newly allocated value with the given Desc, ValueType,
// sample value and label values. It panics if the number of label
// values is different from the number of variable labels in Desc.
func newValue(desc *Desc, valueType ValueType, val float64, labelValues ...string) *value {
if len(labelValues) != len(desc.variableLabels) {
panic(errInconsistentCardinality)
}
result := &value{
desc: desc,
valType: valueType,
valBits: math.Float64bits(val),
labelPairs: makeLabelPairs(desc, labelValues),
}
result.init(result)
return result
}
func (v *value) Desc() *Desc {
return v.desc
}
func (v *value) Set(val float64) {
atomic.StoreUint64(&v.valBits, math.Float64bits(val))
}
func (v *value) SetToCurrentTime() {
v.Set(float64(time.Now().UnixNano()) / 1e9)
}
func (v *value) Inc() {
v.Add(1)
}
func (v *value) Dec() {
v.Add(-1)
}
func (v *value) Add(val float64) {
for {
oldBits := atomic.LoadUint64(&v.valBits)
newBits := math.Float64bits(math.Float64frombits(oldBits) + val)
if atomic.CompareAndSwapUint64(&v.valBits, oldBits, newBits) {
return
}
}
}
func (v *value) Sub(val float64) {
v.Add(val * -1)
}
func (v *value) Write(out *dto.Metric) error {
val := math.Float64frombits(atomic.LoadUint64(&v.valBits))
return populateMetric(v.valType, val, v.labelPairs, out)
}
// 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
@@ -156,10 +77,14 @@ func (v *valueFunc) Write(out *dto.Metric) error {
// operations. However, when implementing custom Collectors, it is useful as a
// throw-away metric that is generated on the fly to send it to Prometheus in
// the Collect method. NewConstMetric returns an error if the length of
// labelValues is not consistent with the variable labels in Desc.
// labelValues is not consistent with the variable labels in Desc or if Desc is
// invalid.
func NewConstMetric(desc *Desc, valueType ValueType, value float64, labelValues ...string) (Metric, error) {
if len(desc.variableLabels) != len(labelValues) {
return nil, errInconsistentCardinality
if desc.err != nil {
return nil, desc.err
}
if err := validateLabelValues(labelValues, len(desc.variableLabels)); err != nil {
return nil, err
}
return &constMetric{
desc: desc,
@@ -231,9 +156,7 @@ func makeLabelPairs(desc *Desc, labelValues []string) []*dto.LabelPair {
Value: proto.String(labelValues[i]),
})
}
for _, lp := range desc.constLabelPairs {
labelPairs = append(labelPairs, lp)
}
sort.Sort(LabelPairSorter(labelPairs))
labelPairs = append(labelPairs, desc.constLabelPairs...)
sort.Sort(labelPairSorter(labelPairs))
return labelPairs
}

View File

@@ -20,33 +20,180 @@ import (
"github.com/prometheus/common/model"
)
// MetricVec is a Collector to bundle metrics of the same name that
// differ in their label values. MetricVec is usually not used directly but as a
// building block for implementations of vectors of a given metric
// type. GaugeVec, CounterVec, SummaryVec, and UntypedVec are examples already
// provided in this package.
type MetricVec struct {
mtx sync.RWMutex // Protects the children.
children map[uint64][]metricWithLabelValues
desc *Desc
// 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
newMetric func(labelValues ...string) Metric
hashAdd func(h uint64, s string) uint64 // replace hash function for testing collision handling
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. The concrete value is
// returned for embedding into another struct.
func newMetricVec(desc *Desc, newMetric func(lvs ...string) Metric) *MetricVec {
return &MetricVec{
children: map[uint64][]metricWithLabelValues{},
desc: desc,
newMetric: newMetric,
// 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 {
@@ -54,166 +201,72 @@ type metricWithLabelValues struct {
metric Metric
}
// Describe implements Collector. The length of the returned slice
// is always one.
func (m *MetricVec) Describe(ch chan<- *Desc) {
// 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 *MetricVec) Collect(ch chan<- Metric) {
func (m *metricMap) Collect(ch chan<- Metric) {
m.mtx.RLock()
defer m.mtx.RUnlock()
for _, metrics := range m.children {
for _, metrics := range m.metrics {
for _, metric := range metrics {
ch <- metric.metric
}
}
}
// GetMetricWithLabelValues returns the Metric 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 Metric is created.
//
// It is possible to call this method without using the returned Metric to only
// create the new Metric but leave it at its start value (e.g. a Summary or
// Histogram without any observations). See also the SummaryVec example.
//
// Keeping the Metric 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 Metric from the MetricVec. In that case, the
// Metric will still exist, but it will not be exported anymore, even if a
// Metric 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.
//
// 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 (m *MetricVec) GetMetricWithLabelValues(lvs ...string) (Metric, error) {
h, err := m.hashLabelValues(lvs)
if err != nil {
return nil, err
}
return m.getOrCreateMetricWithLabelValues(h, lvs), nil
}
// GetMetricWith returns the Metric 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 Metric is created. Implications of
// creating a Metric without using it and keeping the Metric 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.
//
// This method is used for the same purpose as
// GetMetricWithLabelValues(...string). See there for pros and cons of the two
// methods.
func (m *MetricVec) GetMetricWith(labels Labels) (Metric, error) {
h, err := m.hashLabels(labels)
if err != nil {
return nil, err
}
return m.getOrCreateMetricWithLabels(h, labels), nil
}
// WithLabelValues works as GetMetricWithLabelValues, but panics if an error
// occurs. The method allows neat syntax like:
// httpReqs.WithLabelValues("404", "POST").Inc()
func (m *MetricVec) WithLabelValues(lvs ...string) Metric {
metric, err := m.GetMetricWithLabelValues(lvs...)
if err != nil {
panic(err)
}
return metric
}
// With works as GetMetricWith, but panics if an error occurs. The method allows
// neat syntax like:
// httpReqs.With(Labels{"status":"404", "method":"POST"}).Inc()
func (m *MetricVec) With(labels Labels) Metric {
metric, err := m.GetMetricWith(labels)
if err != nil {
panic(err)
}
return metric
}
// 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 {
// Reset deletes all metrics in this vector.
func (m *metricMap) Reset() {
m.mtx.Lock()
defer m.mtx.Unlock()
h, err := m.hashLabelValues(lvs)
if err != nil {
return false
for h := range m.metrics {
delete(m.metrics, h)
}
return m.deleteByHashWithLabelValues(h, lvs)
}
// 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 the Desc of the MetricVec. 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 {
m.mtx.Lock()
defer m.mtx.Unlock()
h, err := m.hashLabels(labels)
if err != nil {
return false
}
return m.deleteByHashWithLabels(h, labels)
}
// deleteByHashWithLabelValues removes the metric from the hash bucket h. If
// there are multiple matches in the bucket, use lvs to select a metric and
// remove only that metric.
func (m *MetricVec) deleteByHashWithLabelValues(h uint64, lvs []string) bool {
metrics, ok := m.children[h]
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 := m.findMetricWithLabelValues(metrics, lvs)
i := findMetricWithLabelValues(metrics, lvs, curry)
if i >= len(metrics) {
return false
}
if len(metrics) > 1 {
m.children[h] = append(metrics[:i], metrics[i+1:]...)
m.metrics[h] = append(metrics[:i], metrics[i+1:]...)
} else {
delete(m.children, h)
delete(m.metrics, h)
}
return true
}
@@ -221,69 +274,38 @@ func (m *MetricVec) deleteByHashWithLabelValues(h uint64, lvs []string) bool {
// deleteByHashWithLabels removes the metric from the hash bucket h. If there
// are multiple matches in the bucket, use lvs to select a metric and remove
// only that metric.
func (m *MetricVec) deleteByHashWithLabels(h uint64, labels Labels) bool {
metrics, ok := m.children[h]
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 := m.findMetricWithLabels(metrics, labels)
i := findMetricWithLabels(m.desc, metrics, labels, curry)
if i >= len(metrics) {
return false
}
if len(metrics) > 1 {
m.children[h] = append(metrics[:i], metrics[i+1:]...)
m.metrics[h] = append(metrics[:i], metrics[i+1:]...)
} else {
delete(m.children, h)
delete(m.metrics, h)
}
return true
}
// Reset deletes all metrics in this vector.
func (m *MetricVec) Reset() {
m.mtx.Lock()
defer m.mtx.Unlock()
for h := range m.children {
delete(m.children, h)
}
}
func (m *MetricVec) hashLabelValues(vals []string) (uint64, error) {
if len(vals) != len(m.desc.variableLabels) {
return 0, errInconsistentCardinality
}
h := hashNew()
for _, val := range vals {
h = m.hashAdd(h, val)
h = m.hashAddByte(h, model.SeparatorByte)
}
return h, nil
}
func (m *MetricVec) hashLabels(labels Labels) (uint64, error) {
if len(labels) != len(m.desc.variableLabels) {
return 0, errInconsistentCardinality
}
h := hashNew()
for _, label := range m.desc.variableLabels {
val, ok := labels[label]
if !ok {
return 0, fmt.Errorf("label name %q missing in label map", label)
}
h = m.hashAdd(h, val)
h = m.hashAddByte(h, model.SeparatorByte)
}
return h, nil
}
// getOrCreateMetricWithLabelValues retrieves the metric by hash and label value
// or creates it and returns the new one.
//
// This function holds the mutex.
func (m *MetricVec) getOrCreateMetricWithLabelValues(hash uint64, lvs []string) Metric {
func (m *metricMap) getOrCreateMetricWithLabelValues(
hash uint64, lvs []string, curry []curriedLabelValue,
) Metric {
m.mtx.RLock()
metric, ok := m.getMetricWithLabelValues(hash, lvs)
metric, ok := m.getMetricWithHashAndLabelValues(hash, lvs, curry)
m.mtx.RUnlock()
if ok {
return metric
@@ -291,13 +313,11 @@ func (m *MetricVec) getOrCreateMetricWithLabelValues(hash uint64, lvs []string)
m.mtx.Lock()
defer m.mtx.Unlock()
metric, ok = m.getMetricWithLabelValues(hash, lvs)
metric, ok = m.getMetricWithHashAndLabelValues(hash, lvs, curry)
if !ok {
// Copy to avoid allocation in case wo don't go down this code path.
copiedLVs := make([]string, len(lvs))
copy(copiedLVs, lvs)
metric = m.newMetric(copiedLVs...)
m.children[hash] = append(m.children[hash], metricWithLabelValues{values: copiedLVs, metric: metric})
inlinedLVs := inlineLabelValues(lvs, curry)
metric = m.newMetric(inlinedLVs...)
m.metrics[hash] = append(m.metrics[hash], metricWithLabelValues{values: inlinedLVs, metric: metric})
}
return metric
}
@@ -306,9 +326,11 @@ func (m *MetricVec) getOrCreateMetricWithLabelValues(hash uint64, lvs []string)
// or creates it and returns the new one.
//
// This function holds the mutex.
func (m *MetricVec) getOrCreateMetricWithLabels(hash uint64, labels Labels) Metric {
func (m *metricMap) getOrCreateMetricWithLabels(
hash uint64, labels Labels, curry []curriedLabelValue,
) Metric {
m.mtx.RLock()
metric, ok := m.getMetricWithLabels(hash, labels)
metric, ok := m.getMetricWithHashAndLabels(hash, labels, curry)
m.mtx.RUnlock()
if ok {
return metric
@@ -316,33 +338,37 @@ func (m *MetricVec) getOrCreateMetricWithLabels(hash uint64, labels Labels) Metr
m.mtx.Lock()
defer m.mtx.Unlock()
metric, ok = m.getMetricWithLabels(hash, labels)
metric, ok = m.getMetricWithHashAndLabels(hash, labels, curry)
if !ok {
lvs := m.extractLabelValues(labels)
lvs := extractLabelValues(m.desc, labels, curry)
metric = m.newMetric(lvs...)
m.children[hash] = append(m.children[hash], metricWithLabelValues{values: lvs, metric: metric})
m.metrics[hash] = append(m.metrics[hash], metricWithLabelValues{values: lvs, metric: metric})
}
return metric
}
// getMetricWithLabelValues gets a metric while handling possible collisions in
// the hash space. Must be called while holding read mutex.
func (m *MetricVec) getMetricWithLabelValues(h uint64, lvs []string) (Metric, bool) {
metrics, ok := m.children[h]
// 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 := m.findMetricWithLabelValues(metrics, lvs); i < len(metrics) {
if i := findMetricWithLabelValues(metrics, lvs, curry); i < len(metrics) {
return metrics[i].metric, true
}
}
return nil, false
}
// getMetricWithLabels gets a metric while handling possible collisions in
// getMetricWithHashAndLabels gets a metric while handling possible collisions in
// the hash space. Must be called while holding read mutex.
func (m *MetricVec) getMetricWithLabels(h uint64, labels Labels) (Metric, bool) {
metrics, ok := m.children[h]
func (m *metricMap) getMetricWithHashAndLabels(
h uint64, labels Labels, curry []curriedLabelValue,
) (Metric, bool) {
metrics, ok := m.metrics[h]
if ok {
if i := m.findMetricWithLabels(metrics, labels); i < len(metrics) {
if i := findMetricWithLabels(m.desc, metrics, labels, curry); i < len(metrics) {
return metrics[i].metric, true
}
}
@@ -351,9 +377,11 @@ func (m *MetricVec) getMetricWithLabels(h uint64, labels Labels) (Metric, bool)
// findMetricWithLabelValues returns the index of the matching metric or
// len(metrics) if not found.
func (m *MetricVec) findMetricWithLabelValues(metrics []metricWithLabelValues, lvs []string) int {
func findMetricWithLabelValues(
metrics []metricWithLabelValues, lvs []string, curry []curriedLabelValue,
) int {
for i, metric := range metrics {
if m.matchLabelValues(metric.values, lvs) {
if matchLabelValues(metric.values, lvs, curry) {
return i
}
}
@@ -362,32 +390,51 @@ func (m *MetricVec) findMetricWithLabelValues(metrics []metricWithLabelValues, l
// findMetricWithLabels returns the index of the matching metric or len(metrics)
// if not found.
func (m *MetricVec) findMetricWithLabels(metrics []metricWithLabelValues, labels Labels) int {
func findMetricWithLabels(
desc *Desc, metrics []metricWithLabelValues, labels Labels, curry []curriedLabelValue,
) int {
for i, metric := range metrics {
if m.matchLabels(metric.values, labels) {
if matchLabels(desc, metric.values, labels, curry) {
return i
}
}
return len(metrics)
}
func (m *MetricVec) matchLabelValues(values []string, lvs []string) bool {
if len(values) != len(lvs) {
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 v != lvs[i] {
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 (m *MetricVec) matchLabels(values []string, labels Labels) bool {
if len(labels) != len(values) {
func matchLabels(desc *Desc, values []string, labels Labels, curry []curriedLabelValue) bool {
if len(values) != len(labels)+len(curry) {
return false
}
for i, k := range m.desc.variableLabels {
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
}
@@ -395,10 +442,31 @@ func (m *MetricVec) matchLabels(values []string, labels Labels) bool {
return true
}
func (m *MetricVec) extractLabelValues(labels Labels) []string {
labelValues := make([]string, len(labels))
for i, k := range m.desc.variableLabels {
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
}

View File

@@ -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
}