Copyright 2017, OpenCensus Authors Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0 Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.

package trace

import (
	
	
	
)
Exporter is a type for functions that receive sampled trace spans. The ExportSpan method should be safe for concurrent use and should return quickly; if an Exporter takes a significant amount of time to process a SpanData, that work should be done on another goroutine. The SpanData should not be modified, but a pointer to it can be kept.
type Exporter interface {
	ExportSpan(s *SpanData)
}

type exportersMap map[Exporter]struct{}

var (
	exporterMu sync.Mutex
	exporters  atomic.Value
)
RegisterExporter adds to the list of Exporters that will receive sampled trace spans. Binaries can register exporters, libraries shouldn't register exporters.
func ( Exporter) {
	exporterMu.Lock()
	 := make(exportersMap)
	if ,  := exporters.Load().(exportersMap);  {
		for ,  := range  {
			[] = 
		}
	}
	[] = struct{}{}
	exporters.Store()
	exporterMu.Unlock()
}
UnregisterExporter removes from the list of Exporters the Exporter that was registered with the given name.
func ( Exporter) {
	exporterMu.Lock()
	 := make(exportersMap)
	if ,  := exporters.Load().(exportersMap);  {
		for ,  := range  {
			[] = 
		}
	}
	delete(, )
	exporters.Store()
	exporterMu.Unlock()
}
SpanData contains all the information collected by a Span.
type SpanData struct {
	SpanContext
	ParentSpanID SpanID
	SpanKind     int
	Name         string
The wall clock time of EndTime will be adjusted to always be offset from StartTime by the duration of the span.
The values of Attributes each have type string, bool, or int64.
	Attributes    map[string]interface{}
	Annotations   []Annotation
	MessageEvents []MessageEvent
	Status
	Links                    []Link
	HasRemoteParent          bool
	DroppedAttributeCount    int
	DroppedAnnotationCount   int
	DroppedMessageEventCount int
	DroppedLinkCount         int
ChildSpanCount holds the number of child span created for this span.
	ChildSpanCount int