58 lines
1.7 KiB
Go
58 lines
1.7 KiB
Go
// 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 view
|
|
|
|
import "sync"
|
|
|
|
var (
|
|
exportersMu sync.RWMutex // guards exporters
|
|
exporters = make(map[Exporter]struct{})
|
|
)
|
|
|
|
// Exporter exports the collected records as view data.
|
|
//
|
|
// The ExportView method should return quickly; if an
|
|
// Exporter takes a significant amount of time to
|
|
// process a Data, that work should be done on another goroutine.
|
|
//
|
|
// It is safe to assume that ExportView will not be called concurrently from
|
|
// multiple goroutines.
|
|
//
|
|
// The Data should not be modified.
|
|
type Exporter interface {
|
|
ExportView(viewData *Data)
|
|
}
|
|
|
|
// RegisterExporter registers an exporter.
|
|
// Collected data will be reported via all the
|
|
// registered exporters. Once you no longer
|
|
// want data to be exported, invoke UnregisterExporter
|
|
// with the previously registered exporter.
|
|
//
|
|
// Binaries can register exporters, libraries shouldn't register exporters.
|
|
func RegisterExporter(e Exporter) {
|
|
exportersMu.Lock()
|
|
defer exportersMu.Unlock()
|
|
|
|
exporters[e] = struct{}{}
|
|
}
|
|
|
|
// UnregisterExporter unregisters an exporter.
|
|
func UnregisterExporter(e Exporter) {
|
|
exportersMu.Lock()
|
|
defer exportersMu.Unlock()
|
|
|
|
delete(exporters, e)
|
|
}
|