| // Copyright 2019 The Go Authors. All rights reserved. | |
| // Use of this source code is governed by a BSD-style | |
| // license that can be found in the LICENSE file. | |
| package telemetry | |
| import "context" | |
| type contextKeyType int | |
| const ( | |
| spanContextKey = contextKeyType(iota) | |
| ) | |
| func WithSpan(ctx context.Context, span *Span) context.Context { | |
| return context.WithValue(ctx, spanContextKey, span) | |
| } | |
| func GetSpan(ctx context.Context) *Span { | |
| v := ctx.Value(spanContextKey) | |
| if v == nil { | |
| return nil | |
| } | |
| return v.(*Span) | |
| } |