The import paths in the built remote entry file do not use the base path configured in vite.config.

[baijunjie]

Under normal circumstances, the reference paths for resource files built by a plugin should align with the base path specified in the Vite config.

The filename of the exposed remote module usually doesn't include a hash because it's the entry point for remote modules and needs to be accessible by external applications. Therefore, it is typically deployed separately on Nginx, while other resources are placed on a CDN. If a relative path is used, it can cause a bug where files can't be found.

vite.config.js

import { federation } from '@module-federation/vite'

export default {
  base: 'https://cdn.example.com/project-name',
  ...
  plugins: [
    federation({
      name: 'remote',
      filename: 'remote.js',
      exposes: {
        './preload': './src/preload',
      },
      shared: [],
    }),
  ],
}

output remote.js

[baijunjie]

For those eager to resolve this issue quickly, I’m providing the following workaround until the author fixes the problem.

vite.config.js

import { federation } from '@module-federation/vite'
import fs from 'node:fs'
import path from 'node:path'

const CDN_ORIGIN = 'https://cdn.example.com/project-name'
export default {
  base: CDN_ORIGIN,
  ...
  plugins: [
    federation({
      name: 'remote',
      filename: 'remote.js',
      exposes: {
        './preload': './src/preload',
      },
      shared: [],
    }),
    {
      name: 'modify-remote-js',
      apply: 'build',
      closeBundle () {
        const outputDir = path.resolve(__dirname, 'dist')
        const fileToProcess = path.join(outputDir, 'remote.js')
        if (fs.existsSync(fileToProcess)) {
          let content = fs.readFileSync(fileToProcess, 'utf-8')
          // For assets deploy to CDN
          content = content.replace(/\.\/assets/g, `${CDN_ORIGIN}/assets`)
          // Fixed: [Uncaught TypeError] i is not a function at hostInit-xxx.js
          content = content.replace('init,', 'init=function(){},')
          fs.writeFileSync(fileToProcess, content)
        }
      },
    },
  ],
}

[gioboa]

Thanks @baijunjie for your help, would you like to drop a PR for that?

[baijunjie]

@gioboa I’m very willing to provide a PR, but there are some issues I haven’t fully understood yet, so I’m not sure how to make the modifications.

I found the template code for the remote entry file, but noticed that the path is a placeholder virtual:mf-exposes. However, I couldn’t locate the relevant code where this placeholder is handled.

/src/virtualModules/virtualExposes.ts

const VIRTUAL_EXPOSES = 'virtual:mf-exposes'

/src/virtualModules/virtualRemoteEntry.ts

`import exposesMap from "${VIRTUAL_EXPOSES}"`

[gioboa]

@baijunjie Thanks, you can search VIRTUAL_EXPOSES and you will find where is used 💪
eg.

if (id === VIRTUAL_EXPOSES) {
  return generateExposes();
}

[baijunjie]

@gioboa I tried debugging generateExposes() and generateRemoteEntry(), but unfortunately, the output is not the final content of the file since it doesn’t include any information about the code file import paths. It seems the final exported content might be unrelated to this plugin. The issue could also lie with Vite or Rollup—I’m not sure.

I have a question: in this case, how exactly is the remote entry file remote.js generated? From the plugin code, it seems to be created through a Vite or Rollup.

[zhangHongEn]

Use https://module-federation.io/configure/manifest.html and configure the remoteEntry file to include a hash for placement on a CDN.