/**
 * Copyright 2018, 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.
 */ import * as crypto from 'crypto' ; const SPAN_ID_RANDOM_BYTES = 8 ; const spanIdBuffer = Buffer . alloc ( SPAN_ID_RANDOM_BYTES ) ; const randomFillSync = crypto . randomFillSync ; const randomBytes = crypto . randomBytes ; const spanRandomBuffer = randomFillSync ? ( ) => randomFillSync ( spanIdBuffer ) : ( ) => randomBytes ( SPAN_ID_RANDOM_BYTES ) ; export function randomSpanId ( ) { return spanRandomBuffer ( ) . toString ( 'hex' ) ; }