github.com/cs3org/reva/v2@v2.27.7/pkg/trace/context.go (about)

     1  // Copyright 2018-2021 CERN
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //     http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  //
    15  // In applying this license, CERN does not waive the privileges and immunities
    16  // granted to it by virtue of its status as an Intergovernmental Organization
    17  // or submit itself to any jurisdiction.
    18  
    19  package trace
    20  
    21  import (
    22  	"context"
    23  
    24  	"go.opentelemetry.io/otel/trace"
    25  	"go.opentelemetry.io/otel/trace/noop"
    26  )
    27  
    28  type ctxKey struct{}
    29  
    30  // ContextSetTracerProvider returns a copy of ctx with p associated.
    31  func ContextSetTracerProvider(ctx context.Context, p trace.TracerProvider) context.Context {
    32  	if tp, ok := ctx.Value(ctxKey{}).(trace.TracerProvider); ok {
    33  		if tp == p {
    34  			return ctx
    35  		}
    36  	}
    37  	return context.WithValue(ctx, ctxKey{}, p)
    38  }
    39  
    40  // ContextGetTracerProvider returns the TracerProvider associated with the ctx.
    41  // If no TracerProvider is associated is associated, the global default TracerProvider
    42  // is returned
    43  func ContextGetTracerProvider(ctx context.Context) trace.TracerProvider {
    44  	if p, ok := ctx.Value(ctxKey{}).(trace.TracerProvider); ok {
    45  		return p
    46  	}
    47  	return noop.NewTracerProvider()
    48  }