Record stdout and stderr from the worker. Add a more detailed example

src/services/calc-queue/CalcQueue.js

@@ -1,3 +1,4 @@
+const dotenv = require('dotenv')
 const EventEmitter = require('events')
 const threads = require('worker_threads')
 const path = require('path')
@@ -6,6 +7,8 @@ const fs = require('fs')
 const Exceptions = require('./exceptions.js')
 const CalcTask = require('./CalcTask.js')
 
+dotenv.config()
+
 // Basic utility functions to help the queue manager
 const CalcQueueUtils = {
   getCalcWorker: function(calcFn) {
@@ -28,8 +31,21 @@ const CalcQueueUtils = {
 
     const task = this.queue.shift()
 
-    task._worker = new threads.Worker(task.workerPath())
+    task._worker = new threads.Worker(
+      task.workerPath(),
+      {
+        stderr: true,
+        stdout: true,
+        workerData: { 'id': task._id }
+      }
+    )
 
+    task._worker.stdout.on('data', (chunk) => {
+      task._stdout = task._stdout.concat(chunk)
+    })
+    task._worker.stderr.on('data', (chunk) => {
+      task._stderr = task._stderr.concat(chunk)
+    })
     task._worker.on('message', (msg) => {
       task._messages.push(msg)
     })
@@ -97,8 +113,19 @@ CalcQueue.prototype = {
         'id': q.id(),
         'calcFn': q.calcFn(),
         'result': q.result(),
+        'stdout': q.stdout().trim().split('\n'),
+        'stderr': q.stderr().trim().split('\n'),
         'messages': q.messages(),
-        'error': (q.error() == null ? null : q.error().message)
+        'error': (
+          q.error() == null
+          ? null
+          : q.error().name + ': ' + q.error().message
+        ),
+        'errorStack': (
+          process.env.NODE_ENV !== 'development' || q.error() == null
+          ? null
+          : q.error().stack.split('\n')
+        )
       }
     })
   },