cloudflared-mirror/vendor/go.opentelemetry.io/otel/internal/global/meter.go

346 lines
9.0 KiB
Go

// Copyright The OpenTelemetry Authors
// SPDX-License-Identifier: Apache-2.0
package global // import "go.opentelemetry.io/otel/internal/global"
import (
"container/list"
"sync"
"sync/atomic"
"go.opentelemetry.io/otel/metric"
"go.opentelemetry.io/otel/metric/embedded"
)
// meterProvider is a placeholder for a configured SDK MeterProvider.
//
// All MeterProvider functionality is forwarded to a delegate once
// configured.
type meterProvider struct {
embedded.MeterProvider
mtx sync.Mutex
meters map[il]*meter
delegate metric.MeterProvider
}
// setDelegate configures p to delegate all MeterProvider functionality to
// provider.
//
// All Meters provided prior to this function call are switched out to be
// Meters provided by provider. All instruments and callbacks are recreated and
// delegated.
//
// It is guaranteed by the caller that this happens only once.
func (p *meterProvider) setDelegate(provider metric.MeterProvider) {
p.mtx.Lock()
defer p.mtx.Unlock()
p.delegate = provider
if len(p.meters) == 0 {
return
}
for _, meter := range p.meters {
meter.setDelegate(provider)
}
p.meters = nil
}
// Meter implements MeterProvider.
func (p *meterProvider) Meter(name string, opts ...metric.MeterOption) metric.Meter {
p.mtx.Lock()
defer p.mtx.Unlock()
if p.delegate != nil {
return p.delegate.Meter(name, opts...)
}
// At this moment it is guaranteed that no sdk is installed, save the meter in the meters map.
c := metric.NewMeterConfig(opts...)
key := il{
name: name,
version: c.InstrumentationVersion(),
}
if p.meters == nil {
p.meters = make(map[il]*meter)
}
if val, ok := p.meters[key]; ok {
return val
}
t := &meter{name: name, opts: opts}
p.meters[key] = t
return t
}
// meter is a placeholder for a metric.Meter.
//
// All Meter functionality is forwarded to a delegate once configured.
// Otherwise, all functionality is forwarded to a NoopMeter.
type meter struct {
embedded.Meter
name string
opts []metric.MeterOption
mtx sync.Mutex
instruments []delegatedInstrument
registry list.List
delegate atomic.Value // metric.Meter
}
type delegatedInstrument interface {
setDelegate(metric.Meter)
}
// setDelegate configures m to delegate all Meter functionality to Meters
// created by provider.
//
// All subsequent calls to the Meter methods will be passed to the delegate.
//
// It is guaranteed by the caller that this happens only once.
func (m *meter) setDelegate(provider metric.MeterProvider) {
meter := provider.Meter(m.name, m.opts...)
m.delegate.Store(meter)
m.mtx.Lock()
defer m.mtx.Unlock()
for _, inst := range m.instruments {
inst.setDelegate(meter)
}
var n *list.Element
for e := m.registry.Front(); e != nil; e = n {
r := e.Value.(*registration)
r.setDelegate(meter)
n = e.Next()
m.registry.Remove(e)
}
m.instruments = nil
m.registry.Init()
}
func (m *meter) Int64Counter(name string, options ...metric.Int64CounterOption) (metric.Int64Counter, error) {
if del, ok := m.delegate.Load().(metric.Meter); ok {
return del.Int64Counter(name, options...)
}
m.mtx.Lock()
defer m.mtx.Unlock()
i := &siCounter{name: name, opts: options}
m.instruments = append(m.instruments, i)
return i, nil
}
func (m *meter) Int64UpDownCounter(name string, options ...metric.Int64UpDownCounterOption) (metric.Int64UpDownCounter, error) {
if del, ok := m.delegate.Load().(metric.Meter); ok {
return del.Int64UpDownCounter(name, options...)
}
m.mtx.Lock()
defer m.mtx.Unlock()
i := &siUpDownCounter{name: name, opts: options}
m.instruments = append(m.instruments, i)
return i, nil
}
func (m *meter) Int64Histogram(name string, options ...metric.Int64HistogramOption) (metric.Int64Histogram, error) {
if del, ok := m.delegate.Load().(metric.Meter); ok {
return del.Int64Histogram(name, options...)
}
m.mtx.Lock()
defer m.mtx.Unlock()
i := &siHistogram{name: name, opts: options}
m.instruments = append(m.instruments, i)
return i, nil
}
func (m *meter) Int64ObservableCounter(name string, options ...metric.Int64ObservableCounterOption) (metric.Int64ObservableCounter, error) {
if del, ok := m.delegate.Load().(metric.Meter); ok {
return del.Int64ObservableCounter(name, options...)
}
m.mtx.Lock()
defer m.mtx.Unlock()
i := &aiCounter{name: name, opts: options}
m.instruments = append(m.instruments, i)
return i, nil
}
func (m *meter) Int64ObservableUpDownCounter(name string, options ...metric.Int64ObservableUpDownCounterOption) (metric.Int64ObservableUpDownCounter, error) {
if del, ok := m.delegate.Load().(metric.Meter); ok {
return del.Int64ObservableUpDownCounter(name, options...)
}
m.mtx.Lock()
defer m.mtx.Unlock()
i := &aiUpDownCounter{name: name, opts: options}
m.instruments = append(m.instruments, i)
return i, nil
}
func (m *meter) Int64ObservableGauge(name string, options ...metric.Int64ObservableGaugeOption) (metric.Int64ObservableGauge, error) {
if del, ok := m.delegate.Load().(metric.Meter); ok {
return del.Int64ObservableGauge(name, options...)
}
m.mtx.Lock()
defer m.mtx.Unlock()
i := &aiGauge{name: name, opts: options}
m.instruments = append(m.instruments, i)
return i, nil
}
func (m *meter) Float64Counter(name string, options ...metric.Float64CounterOption) (metric.Float64Counter, error) {
if del, ok := m.delegate.Load().(metric.Meter); ok {
return del.Float64Counter(name, options...)
}
m.mtx.Lock()
defer m.mtx.Unlock()
i := &sfCounter{name: name, opts: options}
m.instruments = append(m.instruments, i)
return i, nil
}
func (m *meter) Float64UpDownCounter(name string, options ...metric.Float64UpDownCounterOption) (metric.Float64UpDownCounter, error) {
if del, ok := m.delegate.Load().(metric.Meter); ok {
return del.Float64UpDownCounter(name, options...)
}
m.mtx.Lock()
defer m.mtx.Unlock()
i := &sfUpDownCounter{name: name, opts: options}
m.instruments = append(m.instruments, i)
return i, nil
}
func (m *meter) Float64Histogram(name string, options ...metric.Float64HistogramOption) (metric.Float64Histogram, error) {
if del, ok := m.delegate.Load().(metric.Meter); ok {
return del.Float64Histogram(name, options...)
}
m.mtx.Lock()
defer m.mtx.Unlock()
i := &sfHistogram{name: name, opts: options}
m.instruments = append(m.instruments, i)
return i, nil
}
func (m *meter) Float64ObservableCounter(name string, options ...metric.Float64ObservableCounterOption) (metric.Float64ObservableCounter, error) {
if del, ok := m.delegate.Load().(metric.Meter); ok {
return del.Float64ObservableCounter(name, options...)
}
m.mtx.Lock()
defer m.mtx.Unlock()
i := &afCounter{name: name, opts: options}
m.instruments = append(m.instruments, i)
return i, nil
}
func (m *meter) Float64ObservableUpDownCounter(name string, options ...metric.Float64ObservableUpDownCounterOption) (metric.Float64ObservableUpDownCounter, error) {
if del, ok := m.delegate.Load().(metric.Meter); ok {
return del.Float64ObservableUpDownCounter(name, options...)
}
m.mtx.Lock()
defer m.mtx.Unlock()
i := &afUpDownCounter{name: name, opts: options}
m.instruments = append(m.instruments, i)
return i, nil
}
func (m *meter) Float64ObservableGauge(name string, options ...metric.Float64ObservableGaugeOption) (metric.Float64ObservableGauge, error) {
if del, ok := m.delegate.Load().(metric.Meter); ok {
return del.Float64ObservableGauge(name, options...)
}
m.mtx.Lock()
defer m.mtx.Unlock()
i := &afGauge{name: name, opts: options}
m.instruments = append(m.instruments, i)
return i, nil
}
// RegisterCallback captures the function that will be called during Collect.
func (m *meter) RegisterCallback(f metric.Callback, insts ...metric.Observable) (metric.Registration, error) {
if del, ok := m.delegate.Load().(metric.Meter); ok {
insts = unwrapInstruments(insts)
return del.RegisterCallback(f, insts...)
}
m.mtx.Lock()
defer m.mtx.Unlock()
reg := &registration{instruments: insts, function: f}
e := m.registry.PushBack(reg)
reg.unreg = func() error {
m.mtx.Lock()
_ = m.registry.Remove(e)
m.mtx.Unlock()
return nil
}
return reg, nil
}
type wrapped interface {
unwrap() metric.Observable
}
func unwrapInstruments(instruments []metric.Observable) []metric.Observable {
out := make([]metric.Observable, 0, len(instruments))
for _, inst := range instruments {
if in, ok := inst.(wrapped); ok {
out = append(out, in.unwrap())
} else {
out = append(out, inst)
}
}
return out
}
type registration struct {
embedded.Registration
instruments []metric.Observable
function metric.Callback
unreg func() error
unregMu sync.Mutex
}
func (c *registration) setDelegate(m metric.Meter) {
insts := unwrapInstruments(c.instruments)
c.unregMu.Lock()
defer c.unregMu.Unlock()
if c.unreg == nil {
// Unregister already called.
return
}
reg, err := m.RegisterCallback(c.function, insts...)
if err != nil {
GetErrorHandler().Handle(err)
}
c.unreg = reg.Unregister
}
func (c *registration) Unregister() error {
c.unregMu.Lock()
defer c.unregMu.Unlock()
if c.unreg == nil {
// Unregister already called.
return nil
}
var err error
err, c.unreg = c.unreg(), nil
return err
}