[Bug] Can't resolve 'fs'

[hluo-alt]

The issue
When I try to import the Casbin Enforcer, it gives this error:

./node_modules/casbin/lib/esm/enforcer.js:653:27-39 - Error: Module not found: Error: Can't resolve 'fs' in '<PROJECT_DIR>/node_modules/casbin/lib/esm'

I am using Casbin in node.js with node version v16.17.0 and Angular version v14.

Desktop:

• OS: Ubuntu 22.04.3 LTS
• Browser: chrome

[casbin-bot]

@tangyang9464 @JalinWang

[casbin-bot]

@nodece @Shivansh-yadav13

[nodece]

Hi @hluo-alt, please add the following config to package.json:

  "browser": {
    "fs": false
  }

Casbin examples: https://github.com/node-casbin/casbin-examples

[hluo-alt]

Thank you @nodece
I have added the config like you said, but this time it is giving me a new error Uncaught ReferenceError: Buffer is not defined in the Chrome console. Do you have any idea what to do next?

[nodece]

Buffer is built-in library for the Node.js project.

In the Web, you can install this library by “yarn add buffer”.

[hluo-alt]

Thanks, in addition to installing Buffer, I added

import * as Buffer from 'node_modules/buffer';
(window as any).Buffer = Buffer.Buffer;

in polyfills.ts to get it working.

[frisia-mtz]

For people using vite, the plugin vite-plugin-node-polyfills helps alleviate the issue with Buffer in the browser.

The following vite.config.ts worked for me:

import { defineConfig } from 'vite';
import { nodePolyfills } from 'vite-plugin-node-polyfills';

// https://vitejs.dev/config/
export default defineConfig({
  plugins: [
    nodePolyfills({
      globals: { Buffer: true },
    }),
  ],
  // other config
})