Webpack invalid options object when using writeToDisk

Question

I'm trying to use webpack for my web development project, but can't figure out how to use the writeToDisk option.

Here's my webpack.config.development.js file:

const { merge } = require('webpack-merge')
const path = require('path')

const config = require('./webpack.config')

module.exports = merge(config, {
  mode: 'development',

  devtool: 'inline-source-map',

  devServer: {
    writeToDisk: true
  },

  output: {
    path: path.resolve(__dirname, 'public')
  }
})

And the result when I run npm start is the following:

C:\Users
atha\OneDrive\Documents\web\floema>npm start

> floema@1.0.0 start
> npm run development


> floema@1.0.0 development
> webpack serve --progress --config webpack.config.development.js

C:\Users
atha\OneDrive\Documents\web\floema\app C:\Users
atha\OneDrive\Documents\web\floema\assets C:\Users
atha\OneDrive\Documents\web\floema\styles
1% setup initialize[webpack-cli] Invalid options object. Dev Server has been initialized using an options object that does not match the API schema.
 - options has an unknown property 'writeToDisk'. These properties are valid:
   object { allowedHosts?, bonjour?, client?, compress?, devMiddleware?, headers?, historyApiFallback?, host?, hot?, http2?, https?, ipc?, liveReload?, magicHtml?, onAfterSetupMiddleware?, onBeforeSetupMiddleware?, onListening?, open?, port?, proxy?, server?, setupExitSignals?, setupMiddlewares?, static?, watchFiles?, webSocketServer? }

Thanks !

user_11861392 · Answer

As documented in https://github.com/webpack/webpack-dev-server/blob/master/migration-v4.md and https://github.com/webpack/webpack-dev-server/issues/3768, the option writeToDisk was moved to devServer.devMiddleware, so it needs to be configured like this now:

module.exports = {
  devServer: {
    devMiddleware: {
      writeToDisk: true,
    },
  },
};

Webpack invalid options object when using writeToDisk

1 Answers