gotosocial/vendor/go.opentelemetry.io/otel/sdk/metric/meter.go
Tsuribori 1ba3e14b36
[feature] Initial Prometheus metrics implementation (#2334)
* feat: Initial OTEL metrics

* docs: add metrics documentation

* fix: metrics endpoint conditional check

* feat: metrics endpoint basic auth

* fix: make metrics-auth-enabled default false

* fix: go fmt helpers.gen.go

* fix: add metric-related env vars to envparsing.sh

* fix: metrics docs

* fix: metrics related stuff in envparsing.sh

* fix: metrics docs

* chore: metrics docs wording

* fix: metrics stuff in envparsing?

* bump otel versions

---------

Co-authored-by: Tsuribori <user@acertaindebian>
Co-authored-by: Tsuribori <none@example.org>
Co-authored-by: tsmethurst <tobi.smethurst@protonmail.com>
2023-11-20 16:43:55 +01:00

596 lines
20 KiB
Go

// Copyright The OpenTelemetry 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 metric // import "go.opentelemetry.io/otel/sdk/metric"
import (
"context"
"errors"
"fmt"
"go.opentelemetry.io/otel/internal/global"
"go.opentelemetry.io/otel/metric"
"go.opentelemetry.io/otel/metric/embedded"
"go.opentelemetry.io/otel/sdk/instrumentation"
"go.opentelemetry.io/otel/sdk/metric/internal/aggregate"
)
// ErrInstrumentName indicates the created instrument has an invalid name.
// Valid names must consist of 255 or fewer characters including alphanumeric, _, ., -, / and start with a letter.
var ErrInstrumentName = errors.New("invalid instrument name")
// meter handles the creation and coordination of all metric instruments. A
// meter represents a single instrumentation scope; all metric telemetry
// produced by an instrumentation scope will use metric instruments from a
// single meter.
type meter struct {
embedded.Meter
scope instrumentation.Scope
pipes pipelines
int64Resolver resolver[int64]
float64Resolver resolver[float64]
}
func newMeter(s instrumentation.Scope, p pipelines) *meter {
// viewCache ensures instrument conflicts, including number conflicts, this
// meter is asked to create are logged to the user.
var viewCache cache[string, instID]
return &meter{
scope: s,
pipes: p,
int64Resolver: newResolver[int64](p, &viewCache),
float64Resolver: newResolver[float64](p, &viewCache),
}
}
// Compile-time check meter implements metric.Meter.
var _ metric.Meter = (*meter)(nil)
// Int64Counter returns a new instrument identified by name and configured with
// options. The instrument is used to synchronously record increasing int64
// measurements during a computational operation.
func (m *meter) Int64Counter(name string, options ...metric.Int64CounterOption) (metric.Int64Counter, error) {
cfg := metric.NewInt64CounterConfig(options...)
const kind = InstrumentKindCounter
p := int64InstProvider{m}
i, err := p.lookup(kind, name, cfg.Description(), cfg.Unit())
if err != nil {
return i, err
}
return i, validateInstrumentName(name)
}
// Int64UpDownCounter returns a new instrument identified by name and
// configured with options. The instrument is used to synchronously record
// int64 measurements during a computational operation.
func (m *meter) Int64UpDownCounter(name string, options ...metric.Int64UpDownCounterOption) (metric.Int64UpDownCounter, error) {
cfg := metric.NewInt64UpDownCounterConfig(options...)
const kind = InstrumentKindUpDownCounter
p := int64InstProvider{m}
i, err := p.lookup(kind, name, cfg.Description(), cfg.Unit())
if err != nil {
return i, err
}
return i, validateInstrumentName(name)
}
// Int64Histogram returns a new instrument identified by name and configured
// with options. The instrument is used to synchronously record the
// distribution of int64 measurements during a computational operation.
func (m *meter) Int64Histogram(name string, options ...metric.Int64HistogramOption) (metric.Int64Histogram, error) {
cfg := metric.NewInt64HistogramConfig(options...)
p := int64InstProvider{m}
i, err := p.lookupHistogram(name, cfg)
if err != nil {
return i, err
}
return i, validateInstrumentName(name)
}
// Int64ObservableCounter returns a new instrument identified by name and
// configured with options. The instrument is used to asynchronously record
// increasing int64 measurements once per a measurement collection cycle.
// Only the measurements recorded during the collection cycle are exported.
func (m *meter) Int64ObservableCounter(name string, options ...metric.Int64ObservableCounterOption) (metric.Int64ObservableCounter, error) {
cfg := metric.NewInt64ObservableCounterConfig(options...)
const kind = InstrumentKindObservableCounter
p := int64ObservProvider{m}
inst, err := p.lookup(kind, name, cfg.Description(), cfg.Unit())
if err != nil {
return nil, err
}
p.registerCallbacks(inst, cfg.Callbacks())
return inst, validateInstrumentName(name)
}
// Int64ObservableUpDownCounter returns a new instrument identified by name and
// configured with options. The instrument is used to asynchronously record
// int64 measurements once per a measurement collection cycle. Only the
// measurements recorded during the collection cycle are exported.
func (m *meter) Int64ObservableUpDownCounter(name string, options ...metric.Int64ObservableUpDownCounterOption) (metric.Int64ObservableUpDownCounter, error) {
cfg := metric.NewInt64ObservableUpDownCounterConfig(options...)
const kind = InstrumentKindObservableUpDownCounter
p := int64ObservProvider{m}
inst, err := p.lookup(kind, name, cfg.Description(), cfg.Unit())
if err != nil {
return nil, err
}
p.registerCallbacks(inst, cfg.Callbacks())
return inst, validateInstrumentName(name)
}
// Int64ObservableGauge returns a new instrument identified by name and
// configured with options. The instrument is used to asynchronously record
// instantaneous int64 measurements once per a measurement collection cycle.
// Only the measurements recorded during the collection cycle are exported.
func (m *meter) Int64ObservableGauge(name string, options ...metric.Int64ObservableGaugeOption) (metric.Int64ObservableGauge, error) {
cfg := metric.NewInt64ObservableGaugeConfig(options...)
const kind = InstrumentKindObservableGauge
p := int64ObservProvider{m}
inst, err := p.lookup(kind, name, cfg.Description(), cfg.Unit())
if err != nil {
return nil, err
}
p.registerCallbacks(inst, cfg.Callbacks())
return inst, validateInstrumentName(name)
}
// Float64Counter returns a new instrument identified by name and configured
// with options. The instrument is used to synchronously record increasing
// float64 measurements during a computational operation.
func (m *meter) Float64Counter(name string, options ...metric.Float64CounterOption) (metric.Float64Counter, error) {
cfg := metric.NewFloat64CounterConfig(options...)
const kind = InstrumentKindCounter
p := float64InstProvider{m}
i, err := p.lookup(kind, name, cfg.Description(), cfg.Unit())
if err != nil {
return i, err
}
return i, validateInstrumentName(name)
}
// Float64UpDownCounter returns a new instrument identified by name and
// configured with options. The instrument is used to synchronously record
// float64 measurements during a computational operation.
func (m *meter) Float64UpDownCounter(name string, options ...metric.Float64UpDownCounterOption) (metric.Float64UpDownCounter, error) {
cfg := metric.NewFloat64UpDownCounterConfig(options...)
const kind = InstrumentKindUpDownCounter
p := float64InstProvider{m}
i, err := p.lookup(kind, name, cfg.Description(), cfg.Unit())
if err != nil {
return i, err
}
return i, validateInstrumentName(name)
}
// Float64Histogram returns a new instrument identified by name and configured
// with options. The instrument is used to synchronously record the
// distribution of float64 measurements during a computational operation.
func (m *meter) Float64Histogram(name string, options ...metric.Float64HistogramOption) (metric.Float64Histogram, error) {
cfg := metric.NewFloat64HistogramConfig(options...)
p := float64InstProvider{m}
i, err := p.lookupHistogram(name, cfg)
if err != nil {
return i, err
}
return i, validateInstrumentName(name)
}
// Float64ObservableCounter returns a new instrument identified by name and
// configured with options. The instrument is used to asynchronously record
// increasing float64 measurements once per a measurement collection cycle.
// Only the measurements recorded during the collection cycle are exported.
func (m *meter) Float64ObservableCounter(name string, options ...metric.Float64ObservableCounterOption) (metric.Float64ObservableCounter, error) {
cfg := metric.NewFloat64ObservableCounterConfig(options...)
const kind = InstrumentKindObservableCounter
p := float64ObservProvider{m}
inst, err := p.lookup(kind, name, cfg.Description(), cfg.Unit())
if err != nil {
return nil, err
}
p.registerCallbacks(inst, cfg.Callbacks())
return inst, validateInstrumentName(name)
}
// Float64ObservableUpDownCounter returns a new instrument identified by name
// and configured with options. The instrument is used to asynchronously record
// float64 measurements once per a measurement collection cycle. Only the
// measurements recorded during the collection cycle are exported.
func (m *meter) Float64ObservableUpDownCounter(name string, options ...metric.Float64ObservableUpDownCounterOption) (metric.Float64ObservableUpDownCounter, error) {
cfg := metric.NewFloat64ObservableUpDownCounterConfig(options...)
const kind = InstrumentKindObservableUpDownCounter
p := float64ObservProvider{m}
inst, err := p.lookup(kind, name, cfg.Description(), cfg.Unit())
if err != nil {
return nil, err
}
p.registerCallbacks(inst, cfg.Callbacks())
return inst, validateInstrumentName(name)
}
// Float64ObservableGauge returns a new instrument identified by name and
// configured with options. The instrument is used to asynchronously record
// instantaneous float64 measurements once per a measurement collection cycle.
// Only the measurements recorded during the collection cycle are exported.
func (m *meter) Float64ObservableGauge(name string, options ...metric.Float64ObservableGaugeOption) (metric.Float64ObservableGauge, error) {
cfg := metric.NewFloat64ObservableGaugeConfig(options...)
const kind = InstrumentKindObservableGauge
p := float64ObservProvider{m}
inst, err := p.lookup(kind, name, cfg.Description(), cfg.Unit())
if err != nil {
return nil, err
}
p.registerCallbacks(inst, cfg.Callbacks())
return inst, validateInstrumentName(name)
}
func validateInstrumentName(name string) error {
if len(name) == 0 {
return fmt.Errorf("%w: %s: is empty", ErrInstrumentName, name)
}
if len(name) > 255 {
return fmt.Errorf("%w: %s: longer than 255 characters", ErrInstrumentName, name)
}
if !isAlpha([]rune(name)[0]) {
return fmt.Errorf("%w: %s: must start with a letter", ErrInstrumentName, name)
}
if len(name) == 1 {
return nil
}
for _, c := range name[1:] {
if !isAlphanumeric(c) && c != '_' && c != '.' && c != '-' && c != '/' {
return fmt.Errorf("%w: %s: must only contain [A-Za-z0-9_.-/]", ErrInstrumentName, name)
}
}
return nil
}
func isAlpha(c rune) bool {
return ('a' <= c && c <= 'z') || ('A' <= c && c <= 'Z')
}
func isAlphanumeric(c rune) bool {
return isAlpha(c) || ('0' <= c && c <= '9')
}
// RegisterCallback registers f to be called each collection cycle so it will
// make observations for insts during those cycles.
//
// The only instruments f can make observations for are insts. All other
// observations will be dropped and an error will be logged.
//
// Only instruments from this meter can be registered with f, an error is
// returned if other instrument are provided.
//
// Only observations made in the callback will be exported. Unlike synchronous
// instruments, asynchronous callbacks can "forget" attribute sets that are no
// longer relevant by omitting the observation during the callback.
//
// The returned Registration can be used to unregister f.
func (m *meter) RegisterCallback(f metric.Callback, insts ...metric.Observable) (metric.Registration, error) {
if len(insts) == 0 {
// Don't allocate a observer if not needed.
return noopRegister{}, nil
}
reg := newObserver()
var errs multierror
for _, inst := range insts {
// Unwrap any global.
if u, ok := inst.(interface {
Unwrap() metric.Observable
}); ok {
inst = u.Unwrap()
}
switch o := inst.(type) {
case int64Observable:
if err := o.registerable(m); err != nil {
if !errors.Is(err, errEmptyAgg) {
errs.append(err)
}
continue
}
reg.registerInt64(o.observablID)
case float64Observable:
if err := o.registerable(m); err != nil {
if !errors.Is(err, errEmptyAgg) {
errs.append(err)
}
continue
}
reg.registerFloat64(o.observablID)
default:
// Instrument external to the SDK.
return nil, fmt.Errorf("invalid observable: from different implementation")
}
}
err := errs.errorOrNil()
if reg.len() == 0 {
// All insts use drop aggregation or are invalid.
return noopRegister{}, err
}
// Some or all instruments were valid.
cback := func(ctx context.Context) error { return f(ctx, reg) }
return m.pipes.registerMultiCallback(cback), err
}
type observer struct {
embedded.Observer
float64 map[observablID[float64]]struct{}
int64 map[observablID[int64]]struct{}
}
func newObserver() observer {
return observer{
float64: make(map[observablID[float64]]struct{}),
int64: make(map[observablID[int64]]struct{}),
}
}
func (r observer) len() int {
return len(r.float64) + len(r.int64)
}
func (r observer) registerFloat64(id observablID[float64]) {
r.float64[id] = struct{}{}
}
func (r observer) registerInt64(id observablID[int64]) {
r.int64[id] = struct{}{}
}
var (
errUnknownObserver = errors.New("unknown observable instrument")
errUnregObserver = errors.New("observable instrument not registered for callback")
)
func (r observer) ObserveFloat64(o metric.Float64Observable, v float64, opts ...metric.ObserveOption) {
var oImpl float64Observable
switch conv := o.(type) {
case float64Observable:
oImpl = conv
case interface {
Unwrap() metric.Observable
}:
// Unwrap any global.
async := conv.Unwrap()
var ok bool
if oImpl, ok = async.(float64Observable); !ok {
global.Error(errUnknownObserver, "failed to record asynchronous")
return
}
default:
global.Error(errUnknownObserver, "failed to record")
return
}
if _, registered := r.float64[oImpl.observablID]; !registered {
global.Error(errUnregObserver, "failed to record",
"name", oImpl.name,
"description", oImpl.description,
"unit", oImpl.unit,
"number", fmt.Sprintf("%T", float64(0)),
)
return
}
c := metric.NewObserveConfig(opts)
oImpl.observe(v, c.Attributes())
}
func (r observer) ObserveInt64(o metric.Int64Observable, v int64, opts ...metric.ObserveOption) {
var oImpl int64Observable
switch conv := o.(type) {
case int64Observable:
oImpl = conv
case interface {
Unwrap() metric.Observable
}:
// Unwrap any global.
async := conv.Unwrap()
var ok bool
if oImpl, ok = async.(int64Observable); !ok {
global.Error(errUnknownObserver, "failed to record asynchronous")
return
}
default:
global.Error(errUnknownObserver, "failed to record")
return
}
if _, registered := r.int64[oImpl.observablID]; !registered {
global.Error(errUnregObserver, "failed to record",
"name", oImpl.name,
"description", oImpl.description,
"unit", oImpl.unit,
"number", fmt.Sprintf("%T", int64(0)),
)
return
}
c := metric.NewObserveConfig(opts)
oImpl.observe(v, c.Attributes())
}
type noopRegister struct{ embedded.Registration }
func (noopRegister) Unregister() error {
return nil
}
// int64InstProvider provides int64 OpenTelemetry instruments.
type int64InstProvider struct{ *meter }
func (p int64InstProvider) aggs(kind InstrumentKind, name, desc, u string) ([]aggregate.Measure[int64], error) {
inst := Instrument{
Name: name,
Description: desc,
Unit: u,
Kind: kind,
Scope: p.scope,
}
return p.int64Resolver.Aggregators(inst)
}
func (p int64InstProvider) histogramAggs(name string, cfg metric.Int64HistogramConfig) ([]aggregate.Measure[int64], error) {
boundaries := cfg.ExplicitBucketBoundaries()
aggError := AggregationExplicitBucketHistogram{Boundaries: boundaries}.err()
if aggError != nil {
// If boundaries are invalid, ignore them.
boundaries = nil
}
inst := Instrument{
Name: name,
Description: cfg.Description(),
Unit: cfg.Unit(),
Kind: InstrumentKindHistogram,
Scope: p.scope,
}
measures, err := p.int64Resolver.HistogramAggregators(inst, boundaries)
return measures, errors.Join(aggError, err)
}
// lookup returns the resolved instrumentImpl.
func (p int64InstProvider) lookup(kind InstrumentKind, name, desc, u string) (*int64Inst, error) {
aggs, err := p.aggs(kind, name, desc, u)
return &int64Inst{measures: aggs}, err
}
// lookupHistogram returns the resolved instrumentImpl.
func (p int64InstProvider) lookupHistogram(name string, cfg metric.Int64HistogramConfig) (*int64Inst, error) {
aggs, err := p.histogramAggs(name, cfg)
return &int64Inst{measures: aggs}, err
}
// float64InstProvider provides float64 OpenTelemetry instruments.
type float64InstProvider struct{ *meter }
func (p float64InstProvider) aggs(kind InstrumentKind, name, desc, u string) ([]aggregate.Measure[float64], error) {
inst := Instrument{
Name: name,
Description: desc,
Unit: u,
Kind: kind,
Scope: p.scope,
}
return p.float64Resolver.Aggregators(inst)
}
func (p float64InstProvider) histogramAggs(name string, cfg metric.Float64HistogramConfig) ([]aggregate.Measure[float64], error) {
boundaries := cfg.ExplicitBucketBoundaries()
aggError := AggregationExplicitBucketHistogram{Boundaries: boundaries}.err()
if aggError != nil {
// If boundaries are invalid, ignore them.
boundaries = nil
}
inst := Instrument{
Name: name,
Description: cfg.Description(),
Unit: cfg.Unit(),
Kind: InstrumentKindHistogram,
Scope: p.scope,
}
measures, err := p.float64Resolver.HistogramAggregators(inst, boundaries)
return measures, errors.Join(aggError, err)
}
// lookup returns the resolved instrumentImpl.
func (p float64InstProvider) lookup(kind InstrumentKind, name, desc, u string) (*float64Inst, error) {
aggs, err := p.aggs(kind, name, desc, u)
return &float64Inst{measures: aggs}, err
}
// lookupHistogram returns the resolved instrumentImpl.
func (p float64InstProvider) lookupHistogram(name string, cfg metric.Float64HistogramConfig) (*float64Inst, error) {
aggs, err := p.histogramAggs(name, cfg)
return &float64Inst{measures: aggs}, err
}
type int64ObservProvider struct{ *meter }
func (p int64ObservProvider) lookup(kind InstrumentKind, name, desc, u string) (int64Observable, error) {
aggs, err := (int64InstProvider)(p).aggs(kind, name, desc, u)
return newInt64Observable(p.meter, kind, name, desc, u, aggs), err
}
func (p int64ObservProvider) registerCallbacks(inst int64Observable, cBacks []metric.Int64Callback) {
if inst.observable == nil || len(inst.measures) == 0 {
// Drop aggregator.
return
}
for _, cBack := range cBacks {
p.pipes.registerCallback(p.callback(inst, cBack))
}
}
func (p int64ObservProvider) callback(i int64Observable, f metric.Int64Callback) func(context.Context) error {
inst := int64Observer{int64Observable: i}
return func(ctx context.Context) error { return f(ctx, inst) }
}
type int64Observer struct {
embedded.Int64Observer
int64Observable
}
func (o int64Observer) Observe(val int64, opts ...metric.ObserveOption) {
c := metric.NewObserveConfig(opts)
o.observe(val, c.Attributes())
}
type float64ObservProvider struct{ *meter }
func (p float64ObservProvider) lookup(kind InstrumentKind, name, desc, u string) (float64Observable, error) {
aggs, err := (float64InstProvider)(p).aggs(kind, name, desc, u)
return newFloat64Observable(p.meter, kind, name, desc, u, aggs), err
}
func (p float64ObservProvider) registerCallbacks(inst float64Observable, cBacks []metric.Float64Callback) {
if inst.observable == nil || len(inst.measures) == 0 {
// Drop aggregator.
return
}
for _, cBack := range cBacks {
p.pipes.registerCallback(p.callback(inst, cBack))
}
}
func (p float64ObservProvider) callback(i float64Observable, f metric.Float64Callback) func(context.Context) error {
inst := float64Observer{float64Observable: i}
return func(ctx context.Context) error { return f(ctx, inst) }
}
type float64Observer struct {
embedded.Float64Observer
float64Observable
}
func (o float64Observer) Observe(val float64, opts ...metric.ObserveOption) {
c := metric.NewObserveConfig(opts)
o.observe(val, c.Attributes())
}