Electron - Cannot bundle worker code

[alfredalfie123]

Hi!

I am building an electron application using electron-react-boilerplate.
In this boilerplate, I am trying to use threadsjs.
When testing in dev mode everything works great, but unfortunately when trying to pack the app, I am getting the following warning:

[0] WARNING in ./node_modules/electron-debug/index.js 96:45-58
[0] Critical dependency: the request of a dependency is an expression
[0]  @ ./app/main.dev.js
[0]
[0] WARNING in ./node_modules/electron-debug/index.js 97:61-74
[0] Critical dependency: the request of a dependency is an expression
[0]  @ ./app/main.dev.js
[0]
[0] WARNING in ./node_modules/threads/dist-esm/master/implementation.node.js 57:10-99
[0] Critical dependency: the request of a dependency is an expression
[0]  @ ./node_modules/threads/dist-esm/master/implementation.js
[0]  @ ./node_modules/threads/dist-esm/master/index.js
[0]  @ ./node_modules/threads/dist-esm/index.js
[0]  @ ./app/main_handler/main_handler.js
[0]  @ ./app/main.dev.js
[0]
[0] WARNING in ./node_modules/threads/dist-esm/master/implementation.node.js
[0] Module not found: Error: Can't resolve 'ts-node' in 'C:\Users\NC PC\Workspace\skuns\node_modules\threads\dist-esm\master'
[0]  @ ./node_modules/threads/dist-esm/master/implementation.node.js
[0]  @ ./node_modules/threads/dist-esm/master/implementation.js
[0]  @ ./node_modules/threads/dist-esm/master/index.js
[0]  @ ./node_modules/threads/dist-esm/index.js
[0]  @ ./app/main_handler/main_handler.js
[0]  @ ./app/main.dev.js
[0]
[0] WARNING in No instantiations of threads.js workers found.
[0] Please check that:
[0]   1. You have configured Babel / TypeScript to not transpile ES modules
[0]   2. You import `Worker` from `threads` where you use it
[0]
[0] For more details see: https://github.com/andywer/threads-plugin

In webpack.config.main.prod.babel.js, I follow your guide to use the plugins:

const ThreadsPlugin = require('threads-plugin');
...
plugins: [
    new ThreadsPlugin({
      target: 'electron-node-worker'
    }),
   ...
]

Could you please help me to solve this issue?

Best regards.

[andywer]

Hey @alfredalfie123!
I think there is a similar issue on the threads.js repo right now: andywer/threads.js#238

Can you share the code where you spawn the worker?

[alfredalfie123]

Hi @andywer, after trying with latest boilerplate code, It show another warning when building:

0] WARNING in ./node_modules/electron-debug/index.js 96:45-58
[0] Critical dependency: the request of a dependency is an expression
[0]  @ ./app/main.dev.ts
[0] 
[0] WARNING in ./node_modules/electron-debug/index.js 97:61-74
[0] Critical dependency: the request of a dependency is an expression
[0]  @ ./app/main.dev.ts
[0] 
[0] WARNING in ./node_modules/threads/dist-esm/master/implementation.node.js 57:10-99
[0] Critical dependency: the request of a dependency is an expression
[0]  @ ./node_modules/threads/dist-esm/master/implementation.js
[0]  @ ./node_modules/threads/dist-esm/master/index.js
[0]  @ ./node_modules/threads/dist-esm/index.js
[0]  @ ./app/main.dev.ts
[0] 
[0] WARNING in ./node_modules/threads/dist-esm/master/implementation.node.js
[0] Module not found: Error: Can't resolve 'ts-node' in '/home/alfred/workspace/test_worker/node_modules/threads/dist-esm/master'
[0]  @ ./node_modules/threads/dist-esm/master/implementation.node.js
[0]  @ ./node_modules/threads/dist-esm/master/implementation.js
[0]  @ ./node_modules/threads/dist-esm/master/index.js
[0]  @ ./node_modules/threads/dist-esm/index.js
[0]  @ ./app/main.dev.ts

When building finish, I try to open the release file, and then I found out this error:

Require stack:
- /tmp/.mount_ElectrctMdOm/resources/app.asar/main.prod.js
- 
    at Module._resolveFilename (internal/modules/cjs/loader.js:717:15)
    at Function../lib/common/reset-search-paths.ts.Module._resolveFilename (electron/js2c/browser_init.js:7648:16)
    at Function.resolve (internal/modules/cjs/helpers.js:74:19)
    at resolveScriptPath (/tmp/.mount_ElectrctMdOm/resources/app.asar/main.prod.js:2:544068)
    at new Worker (/tmp/.mount_ElectrctMdOm/resources/app.asar/main.prod.js:2:544514)
    at IpcMain.<anonymous> (/tmp/.mount_ElectrctMdOm/resources/app.asar/main.prod.js:2:1889)
    at IpcMain.emit (events.js:203:13)
    at WebContents.<anonymous> (electron/js2c/browser_init.js:3850:15)
    at WebContents.emit (events.js:203:13)
(node:25978) UnhandledPromiseRejectionWarning: Error: Cannot find module '/tmp/.mount_ElectrctMdOm/resources/app.asar/app/0.main.prod.worker.js'
Require stack:
- /tmp/.mount_ElectrctMdOm/resources/app.asar/main.prod.js
- 
    at Module._resolveFilename (internal/modules/cjs/loader.js:717:15)
    at Function../lib/common/reset-search-paths.ts.Module._resolveFilename (electron/js2c/browser_init.js:7648:16)
    at Function.resolve (internal/modules/cjs/helpers.js:74:19)
    at resolveScriptPath (/tmp/.mount_ElectrctMdOm/resources/app.asar/main.prod.js:2:544068)
    at new Worker (/tmp/.mount_ElectrctMdOm/resources/app.asar/main.prod.js:2:544514)
    at IpcMain.<anonymous> (/tmp/.mount_ElectrctMdOm/resources/app.asar/main.prod.js:2:1889)
    at IpcMain.emit (events.js:203:13)
    at WebContents.<anonymous> (electron/js2c/browser_init.js:3850:15)
    at WebContents.emit (events.js:203:13)

Here is the repo which reproduce above one: https://github.com/alfredalfie123/test_worker

[andywer]

I think I know what's going on: threads.js checks if ts-node is available at one point, using a try { require.resolve("ts-node") } catch { /*...*/ }.

Now webpack chokes on the require.resolve("ts-node"), I think.

Can you try to monkey-patch the implementation.node.js file and change require.resolve("ts-node") to eval('require.resolve("ts-node")')? Alternatively you could try adding ts-node to the externals setting of your webpack config.

If that works we can try to fix it permanently in threads.js.

[alfredalfie123]

@andywer After patching implementation.node.js, It still show warning like this when building:

[0] WARNING in ./node_modules/threads/dist-esm/master/implementation.node.js 58:10-99
[0] Critical dependency: the request of a dependency is an expression
[0]  @ ./node_modules/threads/dist-esm/master/implementation.js
[0]  @ ./node_modules/threads/dist-esm/master/index.js
[0]  @ ./node_modules/threads/dist-esm/index.js
[0]  @ ./app/main.dev.ts

And when running release, it show error like this:

(node:30615) UnhandledPromiseRejectionWarning: Error: Cannot find module '/tmp/.mount_ElectrU1rTT5/resources/app.asar/app/0.main.prod.worker.js'
Require stack:
- /tmp/.mount_ElectrU1rTT5/resources/app.asar/main.prod.js
- 
    at Module._resolveFilename (internal/modules/cjs/loader.js:717:15)
    at Function../lib/common/reset-search-paths.ts.Module._resolveFilename (electron/js2c/browser_init.js:7648:16)
    at Function.resolve (internal/modules/cjs/helpers.js:74:19)
    at resolveScriptPath (/tmp/.mount_ElectrU1rTT5/resources/app.asar/main.prod.js:2:544053)
    at new Worker (/tmp/.mount_ElectrU1rTT5/resources/app.asar/main.prod.js:2:544499)
    at IpcMain.<anonymous> (/tmp/.mount_ElectrU1rTT5/resources/app.asar/main.prod.js:2:1889)
    at IpcMain.emit (events.js:203:13)
    at WebContents.<anonymous> (electron/js2c/browser_init.js:3850:15)
    at WebContents.emit (events.js:203:13)
(node:30615) UnhandledPromiseRejectionWarning: Error: Cannot find module '/tmp/.mount_ElectrU1rTT5/resources/app.asar/app/0.main.prod.worker.js'
Require stack:
- /tmp/.mount_ElectrU1rTT5/resources/app.asar/main.prod.js
- 
    at Module._resolveFilename (internal/modules/cjs/loader.js:717:15)
    at Function../lib/common/reset-search-paths.ts.Module._resolveFilename (electron/js2c/browser_init.js:7648:16)
    at Function.resolve (internal/modules/cjs/helpers.js:74:19)
    at resolveScriptPath (/tmp/.mount_ElectrU1rTT5/resources/app.asar/main.prod.js:2:544053)
    at new Worker (/tmp/.mount_ElectrU1rTT5/resources/app.asar/main.prod.js:2:544499)
    at IpcMain.<anonymous> (/tmp/.mount_ElectrU1rTT5/resources/app.asar/main.prod.js:2:1889)
    at IpcMain.emit (events.js:203:13)
    at WebContents.<anonymous> (electron/js2c/browser_init.js:3850:15)
    at WebContents.emit (events.js:203:13)

[andywer]

Sorry for the late response! I hope you haven’t given up yet.

Did you configure your Electron build pipeline as documented here: https://threads.js.org/getting-started#electron?

[andywer]

Any updates on this, @alfredalfie123?

[alfredalfie123]

@andywer sorry for late reply, after bundlinlg threadjs to asar it works perfectly. Thank you for great library