go-ethereum/swarm/spancontext/spancontext.go
Anton Evangelatov 7c9314f231 swarm: integrate OpenTracing; propagate ctx to internal APIs (#17169)
* swarm: propagate ctx, enable opentracing

* swarm/tracing: log error when tracing is misconfigured
2018-07-13 17:40:28 +02:00

50 lines
994 B
Go

package spancontext
import (
"context"
opentracing "github.com/opentracing/opentracing-go"
)
func WithContext(ctx context.Context, sctx opentracing.SpanContext) context.Context {
return context.WithValue(ctx, "span_context", sctx)
}
func FromContext(ctx context.Context) opentracing.SpanContext {
sctx, ok := ctx.Value("span_context").(opentracing.SpanContext)
if ok {
return sctx
}
return nil
}
func StartSpan(ctx context.Context, name string) (context.Context, opentracing.Span) {
tracer := opentracing.GlobalTracer()
sctx := FromContext(ctx)
var sp opentracing.Span
if sctx != nil {
sp = tracer.StartSpan(
name,
opentracing.ChildOf(sctx))
} else {
sp = tracer.StartSpan(name)
}
nctx := context.WithValue(ctx, "span_context", sp.Context())
return nctx, sp
}
func StartSpanFrom(name string, sctx opentracing.SpanContext) opentracing.Span {
tracer := opentracing.GlobalTracer()
sp := tracer.StartSpan(
name,
opentracing.ChildOf(sctx))
return sp
}