add getWorkersQueue method

Author: Rafal Augustyniak

CHANGELOG.md

@@ -5,6 +5,12 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [2.2.0] - 2020-09-17
+
+### Added
+
+- new method: `workerNodes.getUsedWorkersReference` that return list with used workers in pool
+
 ## [2.1.0] - 2020-07-07
 
 ### Added

Readme.md

@@ -26,8 +26,9 @@ $ npm install worker-nodes
     * [.call](#WorkerNodes+call) : <code>Proxy</code>
     * [.ready()](#WorkerNodes+ready) ⇒ <code>Promise</code>
     * [.terminate()](#WorkerNodes+terminate) ⇒ <code>Promise</code>
-    * [.profiler(duration)](#WorkerNodes+profiler)
-    * [.takeSnapshot()](#WorkerNodes+takeSnapshot)
+    * [.profiler(duration)](#WorkerNodes+profiler) ⇒ <code>void</code>
+    * [.takeSnapshot()](#WorkerNodes+takeSnapshot) ⇒ <code>void</code>
+    * [.getUsedWorkers()](#WorkerNodes+getUsedWorkers) ⇒ <code>Array.&lt;Worker&gt;</code>
 
 <a name="new_WorkerNodes_new"></a>
 
@@ -62,7 +63,7 @@ Starts the process of terminating this instance.
 **Returns**: <code>Promise</code> - - resolved when the instance is terminated.  
 <a name="WorkerNodes+profiler"></a>
 
-### workerNodes.profiler(duration)
+### workerNodes.profiler(duration) ⇒ <code>void</code>
 Run CPU Profiler and save result on main process directory
 
 **Kind**: instance method of [<code>WorkerNodes</code>](#WorkerNodes)  
@@ -73,9 +74,15 @@ Run CPU Profiler and save result on main process directory
 
 <a name="WorkerNodes+takeSnapshot"></a>
 
-### workerNodes.takeSnapshot()
+### workerNodes.takeSnapshot() ⇒ <code>void</code>
 Take Heap Snapshot and save result on main process directory
 
+**Kind**: instance method of [<code>WorkerNodes</code>](#WorkerNodes)  
+<a name="WorkerNodes+getUsedWorkers"></a>
+
+### workerNodes.getUsedWorkers() ⇒ <code>Array.&lt;Worker&gt;</code>
+Return list with used workers in pool
+
 **Kind**: instance method of [<code>WorkerNodes</code>](#WorkerNodes)  
 
 <a name="WorkerNodesOptions"></a>

e2e/main.spec.js

@@ -3,6 +3,7 @@ const test = require('ava');
 const WorkerNodes = require('../');
 const errors = require('../lib/errors');
 const { fixture, unique, repeatCall } = require('./utils');
+const { Worker } = require('worker_threads');
 
 test('should be exposed as a constructor function', t => {
     t.throws(() => WorkerNodes(), { instanceOf: TypeError }, "cannot be invoked without 'new'")
@@ -101,3 +102,18 @@ test('should kill worker that got stuck in an infinite loop', async t => {
     // then
     await t.throwsAsync(workerNodes.call.infiniteLoop, { instanceOf: errors.TimeoutError });
 });
+
+test('should return used workers list', async t => {
+    // given
+    const workerNodes = new WorkerNodes(fixture('process-info'), {
+        autoStart: true,
+        maxWorkers: 10,
+        minWorkers: 10
+    });
+    await workerNodes.ready();
+
+    const workersList = workerNodes.getUsedWorkers();
+
+    // then
+    workersList.forEach(worker => t.true(worker instanceof Worker));
+});

lib/pool.js

@@ -347,8 +347,9 @@ class WorkerNodes extends EventEmitter {
 
     /**
      * Run CPU Profiler and save result on main process directory
-     * 
-     * @param {number} duration 
+     *
+     * @param {number} duration
+     * @returns {void}
      */
     profiler(duration) {
         const worker = this.pickWorker();
@@ -360,7 +361,8 @@ class WorkerNodes extends EventEmitter {
 
     /**
      * Take Heap Snapshot and save result on main process directory
-     * 
+     *
+     * @returns {void}
      */
     takeSnapshot() {
         const worker = this.pickWorker();
@@ -369,6 +371,15 @@ class WorkerNodes extends EventEmitter {
             worker.takeSnapshot();
         }
     }
+
+    /**
+     * Return list with used workers in pool
+     *
+     * @returns {Array.<Worker>}
+     */
+    getUsedWorkers() {
+        return this.workersQueue.storage.map(worker => worker.process.child);
+    }
 }
 
 module.exports = WorkerNodes;

lib/worker/child-loader.js

@@ -28,7 +28,9 @@ function callSplitter(requestData) {
         return handleHeapSnapshot(requestData);
     }
 
-    return handleCall(requestData);
+    if (cmd === 'request') {
+        return handleCall(requestData);
+    }
 }
 
 function handleCall(requestData) {

lib/worker/message.js

@@ -9,6 +9,7 @@ const errorMap = {
 
 class Request {
     constructor({ callId, workerId, method, args }) {
+        this.cmd = 'request';
         this.callId = callId;
         this.workerId = workerId;
         this.method = method;

package-lock.json

@@ -1,6 +1,6 @@
 {
     "name": "worker-nodes",
-    "version": "2.1.0",
+    "version": "2.2.0",
     "description": "A library to run cpu-intensive tasks without blocking the event loop.",
     "keywords": [
         "workers",