webpack-dev-server: Hot reload doesn't work in 4.x with ModuleFederationPlugin

Bug report

Webpack dev server doesn’t perform the hot reload properly in conjunction with ModuleFederationPlugin in v4.x but works in v3.x

Actual Behavior

When I set up a simple project using those dependencies:

{
    "name": "test",
    "version": "1.0.0",
    "scripts": {
        "start": "webpack serve --config=config/webpack.dev.js",
        "build": "webpack --config=config/webpack.prod.js"
    },
    "dependencies": {
        "react": "^17.0.1",
        "react-dom": "^17.0.1",
        "react-router-dom": "^5.2.0"
    },
    "devDependencies": {
        "@babel/core": "^7.17.9",
        "@babel/plugin-transform-runtime": "^7.17.0",
        "@babel/preset-env": "^7.16.11",
        "@babel/preset-react": "^7.16.7",
        "babel-loader": "^8.2.4",
        "clean-webpack-plugin": "^4.0.0",
        "html-webpack-plugin": "^5.5.0",
        "webpack": "^5.71.0",
        "webpack-cli": "^4.9.2",
        "webpack-dev-server": "^4.8.1",
        "webpack-merge": "^5.8.0"
    }
}

I manage to startup my application, I can’t see any errors but when I update the source code, the update is not propagated into the browser and the change is visible ONLY after the full reload.

When I downgrade back to 3.x everything works smoothly.

I used this repository as reference: https://github.com/richardtbell/microfrontend-hello-world

Since this repository was quite older, I wanted to update to the latest version of all packages, the only issue I had was with the webpack-dev-server as I mentioned above.

Expected Behavior

A SPA is HOT reloaded as expected

How Do We Reproduce?

  1. Clone https://github.com/richardtbell/microfrontend-hello-world
  2. Go into packages/helloReact
  3. run: npm run start, update App.js, see the change in the browser is being propagated
  4. Update the dependencies with the snippet above.
  5. Do the same
  6. The change won’t be visible, only after reload
  7. Try to downgrade the dev server to 3.x
  8. Everything will work
  9. OR: keep 4.x and remove the ModuleFederationPlugin from the webpack config and the hot reload will work again

Please paste the results of npx webpack-cli info here, and mention other relevant information

❯ npx webpack-cli info

  System:
    OS: macOS 12.3
    CPU: (8) x64 Intel(R) Core(TM) i5-1038NG7 CPU @ 2.00GHz
    Memory: 29.45 MB / 16.00 GB
  Binaries:
    Node: 14.17.2 - ~/.nvm/versions/node/v14.17.2/bin/node
    Yarn: 1.22.15 - ~/.yarn/bin/yarn
    npm: 8.6.0 - ~/.nvm/versions/node/v14.17.2/bin/npm
  Browsers:
    Brave Browser: 99.1.36.119
    Chrome: 100.0.4896.75
    Safari: 15.4
  Packages:
    babel-loader: ^8.2.4 => 8.2.4
    clean-webpack-plugin: ^4.0.0 => 4.0.0
    html-webpack-plugin: ^5.5.0 => 5.5.0
    webpack: ^5.71.0 => 5.72.0
    webpack-cli: ^4.9.2 => 4.9.2
    webpack-dev-server: ^4.8.1 => 4.8.1
    webpack-merge: ^5.8.0 => 5.8.0

About this issue

  • Original URL
  • State: open
  • Created 2 years ago
  • Reactions: 3
  • Comments: 23 (9 by maintainers)

Most upvoted comments

@alexander-akait Thank you for your answer. I hope you can find some time to find a solution to this problem. Anyway, thanks Alexander, for your contribution to many useful things for it community!

@tony-show I will look soon, sorry for delay, a lot of issues

Try to enable https://webpack.js.org/configuration/optimization/#optimizationruntimechunk

Thanks, but it doesn’t work right.

This only works in microfronts where there are no remotes. But where remotes are specified, the page reloads infinitely. (video demo): https://disk.yandex.ru/i/-E5A1LpdhNIn7w

And screenshots: image image

I digged a bit deeper now. It’s still not clear to me where the problem is exactly. I see that messages are exchanged via the websocket and I see that the modules still are reloaded, even with the ModuleFederationPlugin enabled. When debugging, it seems to me that the modules are replaced (hard to judge for me though as I’m not familiar with the webpack dev server code base). When I check the module source in the browser, I also see the updated code.

I think the issue might be rather that React somehow doesn’t manage to re-render the respective components. So the problem would rather be in the React Refresh plugin, which is used by CRA 5. But not yet sure about it. Will have another look tomorrow.