How to use async-hook-jl - 5 common examples

function createNamespace(name) {
  assert.ok(name, 'namespace must be given a name.');

  let namespace = new Namespace(name);
  namespace.id = currentUid;

  asyncHook.addHooks({
    init(uid, handle, provider, parentUid, parentHandle) {
      //parentUid = parentUid || currentUid;  // Suggested usage but appears to work better for tracing modules.
      currentUid = uid;

      //CHAIN Parent's Context onto child if none exists. This is needed to pass net-events.spec
      if (parentUid) {
        namespace._contexts.set(uid, namespace._contexts.get(parentUid));
      } else {
        namespace._contexts.set(currentUid, namespace.active);
      }
    },
    pre(uid, handle) {
      currentUid = uid;
      let context = namespace._contexts.get(uid);
      if (context) {
        namespace.enter(context);

process.namespaces[name] = null;
}

function reset() {
  // must unregister async listeners
  if (process.namespaces) {
    Object.keys(process.namespaces).forEach(function(name) {
      destroyNamespace(name);
    });
  }
  process.namespaces = Object.create(null);
}

process.namespaces = {};

if (asyncHook._state && !asyncHook._state.enabled) {
  asyncHook.enable();
}

// This evolved from a copy of
// Jeff-Lewis, feat(compat): v4.2 for node v4.7-v8 (0ebfb9b  on Jul 21, 2017)
// https://github.com/Jeff-Lewis/cls-hooked/blob/066c6c4027a7924b06997cc6b175b1841342abdc/context-legacy.js

'use strict';

const util = require('util');
const assert = require('assert');
const wrapEmitter = require('emitter-listener');
const asyncHook = require('async-hook-jl');
const unset = require('./unset');

const CONTEXTS_SYMBOL = 'instanaClsHooked@contexts';

const invertedProviders = [];
for (let key in asyncHook.providers) {
  invertedProviders[asyncHook.providers[key]] = key;
}

let currentUid = -1;

module.exports = {
  getNamespace: getNamespace,
  createNamespace: createNamespace,
  destroyNamespace: destroyNamespace,
  reset: reset
};

function Namespace(name) {
  this.name = name;
  // changed in 2.7: no default context
  this.active = null;

// Jeff-Lewis, feat(compat): v4.2 for node v4.7-v8 (0ebfb9b  on Jul 21, 2017)
// https://github.com/Jeff-Lewis/cls-hooked/blob/066c6c4027a7924b06997cc6b175b1841342abdc/context-legacy.js

'use strict';

const util = require('util');
const assert = require('assert');
const wrapEmitter = require('emitter-listener');
const asyncHook = require('async-hook-jl');
const unset = require('./unset');

const CONTEXTS_SYMBOL = 'instanaClsHooked@contexts';

const invertedProviders = [];
for (let key in asyncHook.providers) {
  invertedProviders[asyncHook.providers[key]] = key;
}

let currentUid = -1;

module.exports = {
  getNamespace: getNamespace,
  createNamespace: createNamespace,
  destroyNamespace: destroyNamespace,
  reset: reset
};

function Namespace(name) {
  this.name = name;
  // changed in 2.7: no default context
  this.active = null;
  this._set = [];

}

function reset() {
  // must unregister async listeners
  if (process.namespaces) {
    Object.keys(process.namespaces).forEach(function(name) {
      destroyNamespace(name);
    });
  }
  process.namespaces = Object.create(null);
}

process.namespaces = {};

if (asyncHook._state && !asyncHook._state.enabled) {
  asyncHook.enable();
}