DockerCLI/vendor/go.opentelemetry.io/otel/sdk/trace/id_generator.go

82 lines
2.0 KiB
Go

// Copyright The OpenTelemetry Authors
// SPDX-License-Identifier: Apache-2.0
package trace // import "go.opentelemetry.io/otel/sdk/trace"
import (
"context"
crand "crypto/rand"
"encoding/binary"
"math/rand"
"sync"
"go.opentelemetry.io/otel/trace"
)
// IDGenerator allows custom generators for TraceID and SpanID.
type IDGenerator interface {
// DO NOT CHANGE: any modification will not be backwards compatible and
// must never be done outside of a new major release.
// NewIDs returns a new trace and span ID.
NewIDs(ctx context.Context) (trace.TraceID, trace.SpanID)
// DO NOT CHANGE: any modification will not be backwards compatible and
// must never be done outside of a new major release.
// NewSpanID returns a ID for a new span in the trace with traceID.
NewSpanID(ctx context.Context, traceID trace.TraceID) trace.SpanID
// DO NOT CHANGE: any modification will not be backwards compatible and
// must never be done outside of a new major release.
}
type randomIDGenerator struct {
sync.Mutex
randSource *rand.Rand
}
var _ IDGenerator = &randomIDGenerator{}
// NewSpanID returns a non-zero span ID from a randomly-chosen sequence.
func (gen *randomIDGenerator) NewSpanID(ctx context.Context, traceID trace.TraceID) trace.SpanID {
gen.Lock()
defer gen.Unlock()
sid := trace.SpanID{}
for {
_, _ = gen.randSource.Read(sid[:])
if sid.IsValid() {
break
}
}
return sid
}
// NewIDs returns a non-zero trace ID and a non-zero span ID from a
// randomly-chosen sequence.
func (gen *randomIDGenerator) NewIDs(ctx context.Context) (trace.TraceID, trace.SpanID) {
gen.Lock()
defer gen.Unlock()
tid := trace.TraceID{}
sid := trace.SpanID{}
for {
_, _ = gen.randSource.Read(tid[:])
if tid.IsValid() {
break
}
}
for {
_, _ = gen.randSource.Read(sid[:])
if sid.IsValid() {
break
}
}
return tid, sid
}
func defaultIDGenerator() IDGenerator {
gen := &randomIDGenerator{}
var rngSeed int64
_ = binary.Read(crand.Reader, binary.LittleEndian, &rngSeed)
gen.randSource = rand.New(rand.NewSource(rngSeed))
return gen
}