1 files changed, 595 insertions, 0 deletions
diff --git a/vendor/go.opentelemetry.io/otel/sdk/metric/meter.go b/vendor/go.opentelemetry.io/otel/sdk/metric/meter.go
new file mode 100644
index 000000000..7f51ec512
--- /dev/null
+++ b/vendor/go.opentelemetry.io/otel/sdk/metric/meter.go
@@ -0,0 +1,595 @@
+// 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())
+}