Source: context.go in package go.opentelemetry.io/otel/api/trace

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 trace

import (
	"context"
)

type traceContextKeyType int

const (
	currentSpanKey traceContextKeyType = iota
	remoteContextKey
)

ContextWithSpan creates a new context with a current span set to the passed span.

func ContextWithSpan(ctx context.Context, span Span) context.Context {
	return context.WithValue(ctx, currentSpanKey, span)
}

SpanFromContext returns the current span stored in the context.

func SpanFromContext(ctx context.Context) Span {
	if span, has := ctx.Value(currentSpanKey).(Span); has {
		return span
	}
	return NoopSpan{}
}

ContextWithRemoteSpanContext creates a new context with a remote span context set to the passed span context.

func ContextWithRemoteSpanContext(ctx context.Context, sc SpanContext) context.Context {
	return context.WithValue(ctx, remoteContextKey, sc)
}

RemoteSpanContextFromContext returns the remote span context stored in the context.

func RemoteSpanContextFromContext(ctx context.Context) SpanContext {
	if sc, ok := ctx.Value(remoteContextKey).(SpanContext); ok {
		return sc
	}
	return EmptySpanContext()