github.com/matrixorigin/matrixone@v1.2.0/pkg/util/trace/context.go (about)

     1  // Copyright The OpenTelemetry Authors
     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  // Portions of this file are additionally subject to the following
    16  // copyright.
    17  //
    18  // Copyright (C) 2022 Matrix Origin.
    19  //
    20  // Modified the behavior and the interface of the step.
    21  
    22  package trace
    23  
    24  import (
    25  	"context"
    26  )
    27  
    28  type traceContextKeyType int
    29  
    30  const currentSpanKey traceContextKeyType = iota
    31  
    32  func ContextWithSpan(parent context.Context, span Span) context.Context {
    33  	return context.WithValue(parent, currentSpanKey, span)
    34  }
    35  
    36  func ContextWithSpanContext(parent context.Context, sc SpanContext) context.Context {
    37  	return ContextWithSpan(parent, &NonRecordingSpan{sc: sc})
    38  }
    39  
    40  func SpanFromContext(ctx context.Context) Span {
    41  	if ctx == nil {
    42  		return NoopSpan{}
    43  	}
    44  	if span, ok := ctx.Value(currentSpanKey).(Span); ok {
    45  		return span
    46  	}
    47  	return NoopSpan{}
    48  }