Loading the same native module into TWO node.js threads





.everyoneloves__top-leaderboard:empty,.everyoneloves__mid-leaderboard:empty,.everyoneloves__bot-mid-leaderboard:empty{ height:90px;width:728px;box-sizing:border-box;
}







1















I have a native C++ module that is spun up by a worker thread from node.js, which works great. From within that node module, I can call my native methods like "AddToLog()" and it works great.



I also need to service web requests, which is my dilemma. So I used express and included a file to start it up on a worker thread. That also works fine - both my native code and the express web server are working at the same time.



However, when I try to 'require' my native module in the file that starts the web server, I get an error that the native module could not be registered.



Have I hit a fundamental limitation where node.js cannot load the same native module on two different worker threads? Or this is as simple as a syntax issue?



My hunch is that I can fix this by making the module context aware, but I'm too new to this to know for sure!



I need the express thread to be able to access the module in order to draw its content. So one thread is running a lighting server that collects data and the other services web requests that describe the current state... if it worked!



// SCRIPT 1
'use strict'

const nightdriver = require('./build/Release/nightdriver.node')
const { Worker } = require('worker_threads');

function startserver()
{
nightdriver.addtolog("[index.js] Starting NightDriver Server");
//nightdriver.startserver();
}

const worker = new Worker("./startweb.js");

nightdriver.addtolog("[index.js] Starting Web Server...");
startserver();

// SCRIPT 2
'use strict'
const nightdriver = require('./build/Release/nightdriver.node')
var express = require('express');
var app = express();

app.get('/', function (req, res) {
res.send('Hello World');
})

var server = app.listen(8081, function () {
var host = server.address().address
var port = server.address().port

console.log("Example app listening at http://%s:%s", host, port)
})

events.js:167
throw er; // Unhandled 'error' event
^
Error: Module did not self-register.
at Object.Module._extensions..node (internal/modules/cjs/loader.js:736:18)
at Module.load (internal/modules/cjs/loader.js:605:32)
at tryModuleLoad (internal/modules/cjs/loader.js:544:12)
at Function.Module._load (internal/modules/cjs/loader.js:536:3)
at Module.require (internal/modules/cjs/loader.js:643:17)
at require (internal/modules/cjs/helpers.js:22:18)
at Object.<anonymous> (/Users/dave/OneDrive/Source/Node/nightdriver/startweb.js:2:21)
at Module._compile (internal/modules/cjs/loader.js:707:30)
at Object.Module._extensions..js (internal/modules/cjs/loader.js:718:10)
at Module.load (internal/modules/cjs/loader.js:605:32)
Emitted 'error' event at:
at Worker.[kOnErrorMessage] (internal/worker.js:332:10)
at Worker.[kOnMessage] (internal/worker.js:342:37)
at MessagePort.Worker.(anonymous function).on (internal/worker.js:279:57)
at MessagePort.emit (events.js:182:13)
at MessagePort.onmessage (internal/worker.js:84:8)









share|improve this question





























    1















    I have a native C++ module that is spun up by a worker thread from node.js, which works great. From within that node module, I can call my native methods like "AddToLog()" and it works great.



    I also need to service web requests, which is my dilemma. So I used express and included a file to start it up on a worker thread. That also works fine - both my native code and the express web server are working at the same time.



    However, when I try to 'require' my native module in the file that starts the web server, I get an error that the native module could not be registered.



    Have I hit a fundamental limitation where node.js cannot load the same native module on two different worker threads? Or this is as simple as a syntax issue?



    My hunch is that I can fix this by making the module context aware, but I'm too new to this to know for sure!



    I need the express thread to be able to access the module in order to draw its content. So one thread is running a lighting server that collects data and the other services web requests that describe the current state... if it worked!



    // SCRIPT 1
    'use strict'

    const nightdriver = require('./build/Release/nightdriver.node')
    const { Worker } = require('worker_threads');

    function startserver()
    {
    nightdriver.addtolog("[index.js] Starting NightDriver Server");
    //nightdriver.startserver();
    }

    const worker = new Worker("./startweb.js");

    nightdriver.addtolog("[index.js] Starting Web Server...");
    startserver();

    // SCRIPT 2
    'use strict'
    const nightdriver = require('./build/Release/nightdriver.node')
    var express = require('express');
    var app = express();

    app.get('/', function (req, res) {
    res.send('Hello World');
    })

    var server = app.listen(8081, function () {
    var host = server.address().address
    var port = server.address().port

    console.log("Example app listening at http://%s:%s", host, port)
    })

    events.js:167
    throw er; // Unhandled 'error' event
    ^
    Error: Module did not self-register.
    at Object.Module._extensions..node (internal/modules/cjs/loader.js:736:18)
    at Module.load (internal/modules/cjs/loader.js:605:32)
    at tryModuleLoad (internal/modules/cjs/loader.js:544:12)
    at Function.Module._load (internal/modules/cjs/loader.js:536:3)
    at Module.require (internal/modules/cjs/loader.js:643:17)
    at require (internal/modules/cjs/helpers.js:22:18)
    at Object.<anonymous> (/Users/dave/OneDrive/Source/Node/nightdriver/startweb.js:2:21)
    at Module._compile (internal/modules/cjs/loader.js:707:30)
    at Object.Module._extensions..js (internal/modules/cjs/loader.js:718:10)
    at Module.load (internal/modules/cjs/loader.js:605:32)
    Emitted 'error' event at:
    at Worker.[kOnErrorMessage] (internal/worker.js:332:10)
    at Worker.[kOnMessage] (internal/worker.js:342:37)
    at MessagePort.Worker.(anonymous function).on (internal/worker.js:279:57)
    at MessagePort.emit (events.js:182:13)
    at MessagePort.onmessage (internal/worker.js:84:8)









    share|improve this question

























      1












      1








      1








      I have a native C++ module that is spun up by a worker thread from node.js, which works great. From within that node module, I can call my native methods like "AddToLog()" and it works great.



      I also need to service web requests, which is my dilemma. So I used express and included a file to start it up on a worker thread. That also works fine - both my native code and the express web server are working at the same time.



      However, when I try to 'require' my native module in the file that starts the web server, I get an error that the native module could not be registered.



      Have I hit a fundamental limitation where node.js cannot load the same native module on two different worker threads? Or this is as simple as a syntax issue?



      My hunch is that I can fix this by making the module context aware, but I'm too new to this to know for sure!



      I need the express thread to be able to access the module in order to draw its content. So one thread is running a lighting server that collects data and the other services web requests that describe the current state... if it worked!



      // SCRIPT 1
      'use strict'

      const nightdriver = require('./build/Release/nightdriver.node')
      const { Worker } = require('worker_threads');

      function startserver()
      {
      nightdriver.addtolog("[index.js] Starting NightDriver Server");
      //nightdriver.startserver();
      }

      const worker = new Worker("./startweb.js");

      nightdriver.addtolog("[index.js] Starting Web Server...");
      startserver();

      // SCRIPT 2
      'use strict'
      const nightdriver = require('./build/Release/nightdriver.node')
      var express = require('express');
      var app = express();

      app.get('/', function (req, res) {
      res.send('Hello World');
      })

      var server = app.listen(8081, function () {
      var host = server.address().address
      var port = server.address().port

      console.log("Example app listening at http://%s:%s", host, port)
      })

      events.js:167
      throw er; // Unhandled 'error' event
      ^
      Error: Module did not self-register.
      at Object.Module._extensions..node (internal/modules/cjs/loader.js:736:18)
      at Module.load (internal/modules/cjs/loader.js:605:32)
      at tryModuleLoad (internal/modules/cjs/loader.js:544:12)
      at Function.Module._load (internal/modules/cjs/loader.js:536:3)
      at Module.require (internal/modules/cjs/loader.js:643:17)
      at require (internal/modules/cjs/helpers.js:22:18)
      at Object.<anonymous> (/Users/dave/OneDrive/Source/Node/nightdriver/startweb.js:2:21)
      at Module._compile (internal/modules/cjs/loader.js:707:30)
      at Object.Module._extensions..js (internal/modules/cjs/loader.js:718:10)
      at Module.load (internal/modules/cjs/loader.js:605:32)
      Emitted 'error' event at:
      at Worker.[kOnErrorMessage] (internal/worker.js:332:10)
      at Worker.[kOnMessage] (internal/worker.js:342:37)
      at MessagePort.Worker.(anonymous function).on (internal/worker.js:279:57)
      at MessagePort.emit (events.js:182:13)
      at MessagePort.onmessage (internal/worker.js:84:8)









      share|improve this question














      I have a native C++ module that is spun up by a worker thread from node.js, which works great. From within that node module, I can call my native methods like "AddToLog()" and it works great.



      I also need to service web requests, which is my dilemma. So I used express and included a file to start it up on a worker thread. That also works fine - both my native code and the express web server are working at the same time.



      However, when I try to 'require' my native module in the file that starts the web server, I get an error that the native module could not be registered.



      Have I hit a fundamental limitation where node.js cannot load the same native module on two different worker threads? Or this is as simple as a syntax issue?



      My hunch is that I can fix this by making the module context aware, but I'm too new to this to know for sure!



      I need the express thread to be able to access the module in order to draw its content. So one thread is running a lighting server that collects data and the other services web requests that describe the current state... if it worked!



      // SCRIPT 1
      'use strict'

      const nightdriver = require('./build/Release/nightdriver.node')
      const { Worker } = require('worker_threads');

      function startserver()
      {
      nightdriver.addtolog("[index.js] Starting NightDriver Server");
      //nightdriver.startserver();
      }

      const worker = new Worker("./startweb.js");

      nightdriver.addtolog("[index.js] Starting Web Server...");
      startserver();

      // SCRIPT 2
      'use strict'
      const nightdriver = require('./build/Release/nightdriver.node')
      var express = require('express');
      var app = express();

      app.get('/', function (req, res) {
      res.send('Hello World');
      })

      var server = app.listen(8081, function () {
      var host = server.address().address
      var port = server.address().port

      console.log("Example app listening at http://%s:%s", host, port)
      })

      events.js:167
      throw er; // Unhandled 'error' event
      ^
      Error: Module did not self-register.
      at Object.Module._extensions..node (internal/modules/cjs/loader.js:736:18)
      at Module.load (internal/modules/cjs/loader.js:605:32)
      at tryModuleLoad (internal/modules/cjs/loader.js:544:12)
      at Function.Module._load (internal/modules/cjs/loader.js:536:3)
      at Module.require (internal/modules/cjs/loader.js:643:17)
      at require (internal/modules/cjs/helpers.js:22:18)
      at Object.<anonymous> (/Users/dave/OneDrive/Source/Node/nightdriver/startweb.js:2:21)
      at Module._compile (internal/modules/cjs/loader.js:707:30)
      at Object.Module._extensions..js (internal/modules/cjs/loader.js:718:10)
      at Module.load (internal/modules/cjs/loader.js:605:32)
      Emitted 'error' event at:
      at Worker.[kOnErrorMessage] (internal/worker.js:332:10)
      at Worker.[kOnMessage] (internal/worker.js:342:37)
      at MessagePort.Worker.(anonymous function).on (internal/worker.js:279:57)
      at MessagePort.emit (events.js:182:13)
      at MessagePort.onmessage (internal/worker.js:84:8)






      node.js multithreading worker






      share|improve this question













      share|improve this question











      share|improve this question




      share|improve this question










      asked Nov 22 '18 at 15:28









      DaveDave

      766823




      766823
























          0






          active

          oldest

          votes












          Your Answer






          StackExchange.ifUsing("editor", function () {
          StackExchange.using("externalEditor", function () {
          StackExchange.using("snippets", function () {
          StackExchange.snippets.init();
          });
          });
          }, "code-snippets");

          StackExchange.ready(function() {
          var channelOptions = {
          tags: "".split(" "),
          id: "1"
          };
          initTagRenderer("".split(" "), "".split(" "), channelOptions);

          StackExchange.using("externalEditor", function() {
          // Have to fire editor after snippets, if snippets enabled
          if (StackExchange.settings.snippets.snippetsEnabled) {
          StackExchange.using("snippets", function() {
          createEditor();
          });
          }
          else {
          createEditor();
          }
          });

          function createEditor() {
          StackExchange.prepareEditor({
          heartbeatType: 'answer',
          autoActivateHeartbeat: false,
          convertImagesToLinks: true,
          noModals: true,
          showLowRepImageUploadWarning: true,
          reputationToPostImages: 10,
          bindNavPrevention: true,
          postfix: "",
          imageUploader: {
          brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
          contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
          allowUrls: true
          },
          onDemand: true,
          discardSelector: ".discard-answer"
          ,immediatelyShowMarkdownHelp:true
          });


          }
          });














          draft saved

          draft discarded


















          StackExchange.ready(
          function () {
          StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fstackoverflow.com%2fquestions%2f53434134%2floading-the-same-native-module-into-two-node-js-threads%23new-answer', 'question_page');
          }
          );

          Post as a guest















          Required, but never shown

























          0






          active

          oldest

          votes








          0






          active

          oldest

          votes









          active

          oldest

          votes






          active

          oldest

          votes
















          draft saved

          draft discarded




















































          Thanks for contributing an answer to Stack Overflow!


          • Please be sure to answer the question. Provide details and share your research!

          But avoid



          • Asking for help, clarification, or responding to other answers.

          • Making statements based on opinion; back them up with references or personal experience.


          To learn more, see our tips on writing great answers.




          draft saved


          draft discarded














          StackExchange.ready(
          function () {
          StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fstackoverflow.com%2fquestions%2f53434134%2floading-the-same-native-module-into-two-node-js-threads%23new-answer', 'question_page');
          }
          );

          Post as a guest















          Required, but never shown





















































          Required, but never shown














          Required, but never shown












          Required, but never shown







          Required, but never shown

































          Required, but never shown














          Required, but never shown












          Required, but never shown







          Required, but never shown







          Popular posts from this blog

          Biblatex bibliography style without URLs when DOI exists (in Overleaf with Zotero bibliography)

          ComboBox Display Member on multiple fields

          Is it possible to collect Nectar points via Trainline?