I'm trying to create a JupyterLab extension, it uses typescript.
I've successfully added the package "@types/node" allowing me to use packages such as 'require('http')'.
But as soon as I try to use child process, using 'require("child_process")' I get the following error when trying to build the extension.
ModuleNotFoundError: Module not found: Error: Can't resolve 'child_process' in '/home/fionn/anaconda3/envs/jupyterlab-ext/share/jupyter/lab/staging/node_modules/jupyerlab_xkdc/lib' at factory.create (/home/fionn/anaconda3/envs/jupyterlab-ext/share/jupyter/lab/staging/node_modules/webpack/lib/Compilation.js:535:10) at factory (/home/fionn/anaconda3/envs/jupyterlab-ext/share/jupyter/lab/staging/node_modules/webpack/lib/NormalModuleFactory.js:397:22) at resolver (/home/fionn/anaconda3/envs/jupyterlab-ext/share/jupyter/lab/staging/node_modules/webpack/lib/NormalModuleFactory.js:130:21) at asyncLib.parallel (/home/fionn/anaconda3/envs/jupyterlab-ext/share/jupyter/lab/staging/node_modules/webpack/lib/NormalModuleFactory.js:224:22) at /home/fionn/anaconda3/envs/jupyterlab-ext/share/jupyter/lab/staging/node_modules/neo-async/async.js:2825:7 at /home/fionn/anaconda3/envs/jupyterlab-ext/share/jupyter/lab/staging/node_modules/neo-async/async.js:6886:13 at normalResolver.resolve (/home/fionn/anaconda3/envs/jupyterlab-ext/share/jupyter/lab/staging/node_modules/webpack/lib/NormalModuleFactory.js:214:25) at doResolve (/home/fionn/anaconda3/envs/jupyterlab-ext/share/jupyter/lab/staging/node_modules/enhanced-resolve/lib/Resolver.js:184:12) at hook.callAsync (/home/fionn/anaconda3/envs/jupyterlab-ext/share/jupyter/lab/staging/node_modules/enhanced-resolve/lib/Resolver.js:238:5) at _fn0 (eval at create (/home/fionn/anaconda3/envs/jupyterlab-ext/share/jupyter/lab/staging/node_modules/tapable/lib/HookCodeFactory.js:32:10), <anonymous>:15:1) at resolver.doResolve (/home/fionn/anaconda3/envs/jupyterlab-ext/share/jupyter/lab/staging/node_modules/enhanced-resolve/lib/UnsafeCachePlugin.js:37:5) at hook.callAsync (/home/fionn/anaconda3/envs/jupyterlab-ext/share/jupyter/lab/staging/node_modules/enhanced-resolve/lib/Resolver.js:238:5) at _fn0 (eval at create (/home/fionn/anaconda3/envs/jupyterlab-ext/share/jupyter/lab/staging/node_modules/tapable/lib/HookCodeFactory.js:32:10), <anonymous>:15:1) at hook.callAsync (/home/fionn/anaconda3/envs/jupyterlab-ext/share/jupyter/lab/staging/node_modules/enhanced-resolve/lib/Resolver.js:238:5) at _fn0 (eval at create (/home/fionn/anaconda3/envs/jupyterlab-ext/share/jupyter/lab/staging/node_modules/tapable/lib/HookCodeFactory.js:32:10), <anonymous>:12:1) at resolver.doResolve (/home/fionn/anaconda3/envs/jupyterlab-ext/share/jupyter/lab/staging/node_modules/enhanced-resolve/lib/DescriptionFilePlugin.js:42:38) at hook.callAsync (/home/fionn/anaconda3/envs/jupyterlab-ext/share/jupyter/lab/staging/node_modules/enhanced-resolve/lib/Resolver.js:238:5) at _fn41 (eval at create (/home/fionn/anaconda3/envs/jupyterlab-ext/share/jupyter/lab/staging/node_modules/tapable/lib/HookCodeFactory.js:32:10), <anonymous>:381:1) at resolver.doResolve (/home/fionn/anaconda3/envs/jupyterlab-ext/share/jupyter/lab/staging/node_modules/enhanced-resolve/lib/ModuleKindPlugin.js:23:37) at hook.callAsync (/home/fionn/anaconda3/envs/jupyterlab-ext/share/jupyter/lab/staging/node_modules/enhanced-resolve/lib/Resolver.js:238:5) at _fn0 (eval at create (/home/fionn/anaconda3/envs/jupyterlab-ext/share/jupyter/lab/staging/node_modules/tapable/lib/HookCodeFactory.js:32:10), <anonymous>:15:1) at hook.callAsync (/home/fionn/anaconda3/envs/jupyterlab-ext/share/jupyter/lab/staging/node_modules/enhanced-resolve/lib/Resolver.js:238:5) at _fn0 (eval at create (/home/fionn/anaconda3/envs/jupyterlab-ext/share/jupyter/lab/staging/node_modules/tapable/lib/HookCodeFactory.js:32:10), <anonymous>:15:1) at args (/home/fionn/anaconda3/envs/jupyterlab-ext/share/jupyter/lab/staging/node_modules/enhanced-resolve/lib/forEachBail.js:30:14) at hook.callAsync (/home/fionn/anaconda3/envs/jupyterlab-ext/share/jupyter/lab/staging/node_modules/enhanced-resolve/lib/Resolver.js:238:5) at _fn0 (eval at create (/home/fionn/anaconda3/envs/jupyterlab-ext/share/jupyter/lab/staging/node_modules/tapable/lib/HookCodeFactory.js:32:10), <anonymous>:15:1) at resolver.doResolve (/home/fionn/anaconda3/envs/jupyterlab-ext/share/jupyter/lab/staging/node_modules/enhanced-resolve/lib/UnsafeCachePlugin.js:37:5) at hook.callAsync (/home/fionn/anaconda3/envs/jupyterlab-ext/share/jupyter/lab/staging/node_modules/enhanced-resolve/lib/Resolver.js:238:5) at _fn0 (eval at create (/home/fionn/anaconda3/envs/jupyterlab-ext/share/jupyter/lab/staging/node_modules/tapable/lib/HookCodeFactory.js:32:10), <anonymous>:15:1) at hook.callAsync (/home/fionn/anaconda3/envs/jupyterlab-ext/share/jupyter/lab/staging/node_modules/enhanced-resolve/lib/Resolver.js:238:5) resolve 'child_process' in '/home/fionn/anaconda3/envs/jupyterlab-ext/share/jupyter/lab/staging/node_modules/jupyerlab_xkdc/lib' Parsed request is a module using description file: /home/fionn/anaconda3/envs/jupyterlab-ext/share/jupyter/lab/staging/node_modules/jupyerlab_xkdc/package.json (relative path: ./lib) Field 'browser' doesn't contain a valid alias configuration resolve as module /home/fionn/anaconda3/envs/jupyterlab-ext/share/jupyter/lab/staging/node_modules/jupyerlab_xkdc/lib/node_modules doesn't exist or is not a directory /home/fionn/anaconda3/envs/jupyterlab-ext/share/jupyter/lab/staging/node_modules/node_modules doesn't exist or is not a directory /home/fionn/anaconda3/envs/jupyterlab-ext/share/jupyter/lab/node_modules doesn't exist or is not a directory /home/fionn/anaconda3/envs/jupyterlab-ext/share/jupyter/node_modules doesn't exist or is not a directory /home/fionn/anaconda3/envs/jupyterlab-ext/share/node_modules doesn't exist or is not a directory /home/fionn/anaconda3/envs/jupyterlab-ext/node_modules doesn't exist or is not a directory /home/fionn/anaconda3/envs/node_modules doesn't exist or is not a directory /home/fionn/anaconda3/node_modules doesn't exist or is not a directory /home/fionn/node_modules doesn't exist or is not a directory /home/node_modules doesn't exist or is not a directory /node_modules doesn't exist or is not a directory looking for modules in /home/fionn/anaconda3/envs/jupyterlab-ext/share/jupyter/lab/staging/node_modules/jupyerlab_xkdc/node_modules using description file: /home/fionn/anaconda3/envs/jupyterlab-ext/share/jupyter/lab/staging/node_modules/jupyerlab_xkdc/package.json (relative path: ./node_modules) Field 'browser' doesn't contain a valid alias configuration looking for modules in /home/fionn/anaconda3/envs/jupyterlab-ext/share/jupyter/lab/staging/node_modules using description file: /home/fionn/anaconda3/envs/jupyterlab-ext/share/jupyter/lab/staging/package.json (relative path: ./node_modules) Field 'browser' doesn't contain a valid alias configuration using description file: /home/fionn/anaconda3/envs/jupyterlab-ext/share/jupyter/lab/staging/node_modules/child_process/package.json (relative path: .) no extension Field 'browser' doesn't contain a valid alias configuration using description file: /home/fionn/anaconda3/envs/jupyterlab-ext/share/jupyter/lab/staging/node_modules/jupyerlab_xkdc/package.json (relative path: ./node_modules/child_process) no extension Field 'browser' doesn't contain a valid alias configuration /home/fionn/anaconda3/envs/jupyterlab-ext/share/jupyter/lab/staging/node_modules/child_process is not a file .wasm Field 'browser' doesn't contain a valid alias configuration /home/fionn/anaconda3/envs/jupyterlab-ext/share/jupyter/lab/staging/node_modules/jupyerlab_xkdc/node_modules/child_process doesn't exist .wasm Field 'browser' doesn't contain a valid alias configuration /home/fionn/anaconda3/envs/jupyterlab-ext/share/jupyter/lab/staging/node_modules/child_process.wasm doesn't exist .mjs Field 'browser' doesn't contain a valid alias configuration /home/fionn/anaconda3/envs/jupyterlab-ext/share/jupyter/lab/staging/node_modules/jupyerlab_xkdc/node_modules/child_process.wasm doesn't exist .mjs Field 'browser' doesn't contain a valid alias configuration /home/fionn/anaconda3/envs/jupyterlab-ext/share/jupyter/lab/staging/node_modules/child_process.mjs doesn't exist .js Field 'browser' doesn't contain a valid alias configuration /home/fionn/anaconda3/envs/jupyterlab-ext/share/jupyter/lab/staging/node_modules/jupyerlab_xkdc/node_modules/child_process.mjs doesn't exist .js Field 'browser' doesn't contain a valid alias configuration /home/fionn/anaconda3/envs/jupyterlab-ext/share/jupyter/lab/staging/node_modules/child_process.js doesn't exist .json Field 'browser' doesn't contain a valid alias configuration /home/fionn/anaconda3/envs/jupyterlab-ext/share/jupyter/lab/staging/node_modules/jupyerlab_xkdc/node_modules/child_process.js doesn't exist .json Field 'browser' doesn't contain a valid alias configuration /home/fionn/anaconda3/envs/jupyterlab-ext/share/jupyter/lab/staging/node_modules/child_process.json doesn't exist /home/fionn/anaconda3/envs/jupyterlab-ext/share/jupyter/lab/staging/node_modules/jupyerlab_xkdc/node_modules/child_process.json doesn't exist as directory existing directory use ./index.js from main in package.json using description file: /home/fionn/anaconda3/envs/jupyterlab-ext/share/jupyter/lab/staging/node_modules/child_process/package.json (relative path: .) Field 'browser' doesn't contain a valid alias configuration as directory /home/fionn/anaconda3/envs/jupyterlab-ext/share/jupyter/lab/staging/node_modules/jupyerlab_xkdc/node_modules/child_process doesn't exist using description file: /home/fionn/anaconda3/envs/jupyterlab-ext/share/jupyter/lab/staging/node_modules/child_process/package.json (relative path: ./index.js) no extension Field 'browser' doesn't contain a valid alias configuration /home/fionn/anaconda3/envs/jupyterlab-ext/share/jupyter/lab/staging/node_modules/child_process/index.js doesn't exist .wasm Field 'browser' doesn't contain a valid alias configuration /home/fionn/anaconda3/envs/jupyterlab-ext/share/jupyter/lab/staging/node_modules/child_process/index.js.wasm doesn't exist .mjs Field 'browser' doesn't contain a valid alias configuration /home/fionn/anaconda3/envs/jupyterlab-ext/share/jupyter/lab/staging/node_modules/child_process/index.js.mjs doesn't exist .js Field 'browser' doesn't contain a valid alias configuration /home/fionn/anaconda3/envs/jupyterlab-ext/share/jupyter/lab/staging/node_modules/child_process/index.js.js doesn't exist .json Field 'browser' doesn't contain a valid alias configuration /home/fionn/anaconda3/envs/jupyterlab-ext/share/jupyter/lab/staging/node_modules/child_process/index.js.json doesn't exist as directory /home/fionn/anaconda3/envs/jupyterlab-ext/share/jupyter/lab/staging/node_modules/child_process/index.js doesn't exist using path: /home/fionn/anaconda3/envs/jupyterlab-ext/share/jupyter/lab/staging/node_modules/child_process/index using description file: /home/fionn/anaconda3/envs/jupyterlab-ext/share/jupyter/lab/staging/node_modules/child_process/package.json (relative path: ./index) no extension Field 'browser' doesn't contain a valid alias configuration /home/fionn/anaconda3/envs/jupyterlab-ext/share/jupyter/lab/staging/node_modules/child_process/index doesn't exist .wasm Field 'browser' doesn't contain a valid alias configuration /home/fionn/anaconda3/envs/jupyterlab-ext/share/jupyter/lab/staging/node_modules/child_process/index.wasm doesn't exist .mjs Field 'browser' doesn't contain a valid alias configuration /home/fionn/anaconda3/envs/jupyterlab-ext/share/jupyter/lab/staging/node_modules/child_process/index.mjs doesn't exist .js Field 'browser' doesn't contain a valid alias configuration /home/fionn/anaconda3/envs/jupyterlab-ext/share/jupyter/lab/staging/node_modules/child_process/index.js doesn't exist .json Field 'browser' doesn't contain a valid alias configuration /home/fionn/anaconda3/envs/jupyterlab-ext/share/jupyter/lab/staging/node_modules/child_process/index.json doesn't exist error Command failed with exit code 1. I've googled around but still have no idea what to do to resolve this issue.
Any pointers or info at all would be greatly appreciated.
My packages.json file.
{ "name": "jupyerlab_xkdc", "version": "0.1.0", "description": "Short description", "keywords": [ "jupyter", "jupyterlab", "jupyterlab-extension" ], "homepage": "", "bugs": { "url": "" }, "license": "BSD-3-Clause", "author": "Fionn McKnight", "files": [ "lib/**/*.{d.ts,eot,gif,html,jpg,js,js.map,json,png,svg,woff2,ttf}", "style/**/*.{css,eot,gif,html,jpg,json,png,svg,woff2,ttf}" ], "main": "lib/index.js", "types": "lib/index.d.ts", "repository": { "type": "git", "url": "" }, "scripts": { "build": "tsc", "clean": "rimraf lib", "prepare": "npm run clean && npm run build", "watch": "tsc -w" }, "dependencies": { "@jupyterlab/application": "^0.19.1", "@jupyterlab/apputils": "^0.19.1", "@phosphor/coreutils": "^1.3.0", "@phosphor/messaging": "^1.2.2", "@phosphor/widgets": "^1.6.0", "@types/jquery": "^3.3.29", "@types/node": "^10.12.19", "child_process": "^1.0.2", "npm": "^6.7.0" }, "devDependencies": { "@types/node": "^10.12.19", "rimraf": "^2.6.1", "typescript": "~3.1.1" }, "jupyterlab": { "extension": true } } 7 Answers
just put in package.json
"browser":{ "child_process": false } are you using webpack
6I got a similar error while trying to run storybook.js which uses webpack.
For Webpack
You can add the following to the webpack's config to fix the build -
// webpack.config.js ..., node: { child_process: "empty" // fs: "empty", // if unable to resolve "fs" }, You can also set other conflicting modules to "empty" if they are responsible for breaking the build.
Reference for Webpack's config.node
In newer versions I used:
// webpack.config.js ..., resolve: { extensions: [".ts", ".js"], fallback: { "child_process": false, // and also other packages that are not found } }, I stayed blocked for a couple of times on that. As far I understood, it seems impossible to execute some child_process ( which is literally executing some cmd ) from the browser, which also makes sense at some point. The solution given works for me, adding below to package.json is working
"browser": { "fs": false, "child_process": false } But don't add it on your package.json (mean the one of your app), but instead the package.json from the lib then you are using where the require('child_process') is.
That's being done, this fixe just said to the compiler that's it's ok to not have a lib even if this one is required somewhere on your code or dependencies (rather to crash ). If you want to use child_process from your App I am afraid that it's complicated.
Here is the source of my post
Randomly Got this issue while using next.js I got it resolved by clearing out,
.next node_modules folders Guess it may work for people getting this client process error in next js
3I got this in next.js after importing path and fs in a page.
Solved it by placing them in the getStaticProps() function.
Same happened
Figured out why it happened
By mistake import was added to file that created issue
import { debug } from "webpack"; 
