github.com/codingfuture/orig-energi3@v0.8.4/swarm/spancontext/spancontext.go (about)

     1  // Copyright 2018 The Energi Core Authors
     2  // Copyright 2018 The go-ethereum Authors
     3  // This file is part of the Energi Core library.
     4  //
     5  // The Energi Core library is free software: you can redistribute it and/or modify
     6  // it under the terms of the GNU Lesser General Public License as published by
     7  // the Free Software Foundation, either version 3 of the License, or
     8  // (at your option) any later version.
     9  //
    10  // The Energi Core library is distributed in the hope that it will be useful,
    11  // but WITHOUT ANY WARRANTY; without even the implied warranty of
    12  // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
    13  // GNU Lesser General Public License for more details.
    14  //
    15  // You should have received a copy of the GNU Lesser General Public License
    16  // along with the Energi Core library. If not, see <http://www.gnu.org/licenses/>.
    17  
    18  package spancontext
    19  
    20  import (
    21  	"context"
    22  
    23  	opentracing "github.com/opentracing/opentracing-go"
    24  )
    25  
    26  func WithContext(ctx context.Context, sctx opentracing.SpanContext) context.Context {
    27  	return context.WithValue(ctx, "span_context", sctx)
    28  }
    29  
    30  func FromContext(ctx context.Context) opentracing.SpanContext {
    31  	sctx, ok := ctx.Value("span_context").(opentracing.SpanContext)
    32  	if ok {
    33  		return sctx
    34  	}
    35  
    36  	return nil
    37  }
    38  
    39  func StartSpan(ctx context.Context, name string) (context.Context, opentracing.Span) {
    40  	tracer := opentracing.GlobalTracer()
    41  
    42  	sctx := FromContext(ctx)
    43  
    44  	var sp opentracing.Span
    45  	if sctx != nil {
    46  		sp = tracer.StartSpan(
    47  			name,
    48  			opentracing.ChildOf(sctx))
    49  	} else {
    50  		sp = tracer.StartSpan(name)
    51  	}
    52  
    53  	nctx := context.WithValue(ctx, "span_context", sp.Context())
    54  
    55  	return nctx, sp
    56  }
    57  
    58  func StartSpanFrom(name string, sctx opentracing.SpanContext) opentracing.Span {
    59  	tracer := opentracing.GlobalTracer()
    60  
    61  	sp := tracer.StartSpan(
    62  		name,
    63  		opentracing.ChildOf(sctx))
    64  
    65  	return sp
    66  }